RNID fire alarm re-design by FreddieJordanDesign

AFFA - Adjustable Frequency Fire Alarm Investigating smoke alarm systems for a totally inclusive market. Supported by

Freddie Jordan 0603918 Major Project Industrial Design & Technology Brunel University AFFA - Adjustable Frequency Fire Alarm

AFFA - Adjustable Frequency Fire Alarm

Contents 1.0 2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0 11.0 12.0 13.0 14.0 15.0 16.0 17.0 18.0 19.0 20.0 21.0 22.0 23.0 24.0 25.0 26.0 27.0 28.0 29.0 30.0 31.0 32.0 33.0 34.0 35.0 36.0 37.0 38.0 39.0 40.0 41.0 42.0 43.0 44.0 45.0 46.0 47.0

Abstract Introduction Design Brief Hearing Psysiology The Hearing Spectrum Audiograms and Interpretation Hard of Hearing The perception of Sound Hearing Aids Ways of alerting people Current Alert Systems Target Market Personas Streamlined Lifecycle Analysis of current RNID alarm Dewhurst and Boothroyd Analysis of RNID Fire Alarm Concept Generation Product Selection User Research initial Development Final Concept Preliminary Product Design Specification Electronics Development Filtering Alarm System Component Development Programming Development - Flow Charts Frequency Testing PCB Development Evaluation of filtering system prototype. Wireless Alarm System Prototype Wireless Alarm System Programming PCB Development Wireless Alarm System Testing Switch Development & User interaction Evaluation of Wireless system prototype User Feedback System Development Clarification RNID Brand Aesthetic Development Material Consideration Product Placement FMEA of AFFA solution Solidworks Development User Feedback on Aesthetic model Service Development Bill of Materials Route to Market Return on Investment

AFFA - Adjustable Frequency Fire Alarm

7 8 9 10-11 12 13-14 15 16-17 18 19 20-21 22 23 24-25 26 27 28 29 30-31 32 33-37 38 39-42 43 44 45 46 47 48-49 50 50 51-52 52-53 54 55-57 58 59 60-61 61 62 63 64 65 66 67 68 69 54

48.0 Evaluation of product against PDS 49.0 External Evaluation 50.0 Final Project Review 51.0 Further Development 52.0 Acknowledgements 53.0 References 54.0 Appendices

AFFA - Adjustable Frequency Fire Alarm

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AFFA - Adjustable Frequency Fire Alarm

1.0 Abstract This report contains the research and development undertaken on a new adjustable frequency fire alarm system for deaf and hard of hearing people. Documented are primary and secondary research findings that give rise to the development of the final product. Research includes looking into how people hear sound, the different types of hearing loss, perception of sound, the function of hearing aids and current specialist product investigation. The research undertaken has been thorough, with analysis and conclusions drawn. Product development in terms of prototypes have been undertaken and product placement and justification described. The future feasibility of production has been touched upon and final models have been realised in both mechanical and aesthetic forms. The final electronic model demonstrates how the product works. The alarm can be set to high (3100hz), medium (1500hz) and low (520hz) frequencies designed to cater for people with all types of hearing loss. Regardless of the frequency setting, one alarm being triggered from the Hallway causes a Bedroom alarm to sound through wireless interaction. A person with ski-slope hearing would prefer the alarm at 520 hz, where as a person with minimal hearing loss 3100hz will be more likely to react to the industry standard frequency. A final aesthetic model has also been produced to give indication on size and feel of product. Keywords: Inclusive Design, Deafness, Fire Alarm, RNID

AFFA - Adjustable Frequency Fire Alarm

2.0 Introduction With hearing loss being a potential problem for people of all ages, and 3 out 4 fire deaths happening in a domestic setting (Pollution Issues, 2008), fire safety in the home is incredibly important. Over 9 million people in the UK are estimated to be deaf or hard of hearing (RNID, 2009). Around 2% of young adults are deaf or hard of hearing, 3.5 million are of working age (16-65) and at the age of 50 the proportion of deaf people begins to increase sharply with 55% of people over 60 having hearing problems (RNID, 2009). There are at least 4 million people who do not have hearing aids but would benefit from using them (RNID, 2009). Hearing loss affects 2 in 10 people in the UK alone with the most common loss being Presbyacusis, which is gradual loss with age. (Bupa, 2009). In 2008, the UK fire and rescue services attended 727,000 incidents, and the total deaths due to fire were 453 (UK Government Fire Statistics, 2008). 90 of these were caused by non-functioning fire alarms (Pollution Issues, 2009). By analysing various issues, the following research will examine possibilities for designing an inclusive fire alarm that can be used by a specialist market as well as the general population.

AFFA - Adjustable Frequency Fire Alarm

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3.0 Design Brief Background With deaf and hard of hearing people not currently being offered access to mainstream fire safety products, consider different aspects to design a new solution. With research having been carried out proving that the conventional alarm may not be the best, look to analysis and test key data, to find a market niche. Consider carefully the different ranges at which people hear, and avoid designing a product which aesthetically creates a negative stigma.

Aims Produce an Inclusively designed Fire Alarm system which caters for deaf and hard of hearing people. The design must be able to alert deaf and hard of hearing people whether they are awake or asleep. Take into account the science of hearing, perception of sound and human factors.

Objectives To complete an in-depth study of how humans hear and perceive sound, resulting in conclusions as to what the next step for smoke alarm devices for hard of hearing people should be. Provide a simple interface to allow the user to listen and set the sound of their device. Brief

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Communicate

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• Design • Appraise • • • • • • • •

Prototype Build Test Operate Maintain Enhance Modify Produce

Figure 1 : Design Process Chart with development at each stage. AFFA - Adjustable Frequency Fire Alarm

4.0 Hearing Physiology An important part of looking to design a product for people with hearing difficulties is firstly understanding how the ear functions and the different types of hearing loss people can have. The ear is made up from 3 different sections, the outer, middle and inner ear.

4.1 Outer Ear The outer ear offers protection, boosts high frequency sounds, and allows for identification as to where a sound is coming from, this is known as localisation (White, 10). The ear localises sound by establishing both the inter-aural time difference and inter-aural intensity difference. The outer ear made up of the Pinna, and the external auditory meatus known as the ear canal. The ear canal is made up of the outer section one third skin and cartilage and two third inner leading to the middle ear junction known as the osseocartilaginous junction. (White, 10).

4.2 Middle Ear The Ear drum is the border between outer ear and middle ear and is known as the tympanic membrane, middle ear is air filled cavity which has 3 bones called the Stapes, Malleus and Incus bones as well as 2 muscles known as the Tensor tympani and the Stapedius. (White, 10)

4.3 Inner ear The inner ear , known as the labyrinth because of its complicated structure lies entirely within the temporal bone of the skull. (Maltby â&#x20AC;&#x2DC;02). The Inner ear is the only section of the ear that is fluid filled and contains the Cochlea, (the organ of hearing). The Cochlea contains the organ of Corti which is the part of the Cochlea that allows sound to be heard.

Figure 2 : Diagram Depicting parts of the ear AFFA - Adjustable Frequency Fire Alarm

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4.4 The Organ of Corti Within the Corti there are both outer and inner hair cells, there are 3 rows in the outer and 1 row in the inner., the inner and outer cells are separated by the Rod of Corti. Located in the middle hair cells, along the Basilar membrane is the tunnel of Corti. This is a ‘snail’ like organ has receptors located all along it, high frequency sound is received by the those at the base of the Corti and low frequency at the apex (Helicotrema) section. (White, ‘10) Being organised in this way, known as Tontotopic organisation, it means that all sound that is heard has to travel across the base section, meaning even if a sound is of a low frequency, the high frequency hair cells still get disturbed. This is because sound has to go through the high frequency hair cells to get to the low frequency ones. There are around 3,500 inner hair cells and 1,200 out hair cells. These hairs are known as the Stereocilia are very tiny hair cells that sit on top of the outer & inner hair cells, they are stiff but can bend. The bending of the stereocilia allows for chemical changes in the auditory signal. The inner hair cells carry afferent (sensory) information whilst, the outer hair cells carry efferent (motor) information to the brain. In order to reach the auditory cortex information passes from the Cochlea through the Cochlear nucleus, superior olive, lateral lemniscus, inferior colliculus, medial geniculate body and auditory cortex. At the superior olive, information crosses over from the right side of brain to left side (contralateral organisation). (White ‘10). The most important aspect in terms of hearing loss to understand from this information is how sound has to travel over the high frequency receptors, regardless of what its frequency is. This is why the most common type of hearing loss in elderly people is ski-slope hearing loss as the high frequency receptors have been exposed to sound for a longer period of time than that of a younger person.

Figure 3 : Diagram Depicting the Corti AFFA - Adjustable Frequency Fire Alarm

5.0 The Hearing Spectrum Experiments have shown that a healthy young person is able to hear all sound frequencies from 20 to 20,000Hz (Rolfe, 09) Although humans are able to hear in this range, audiologists only measure from 250hz to 8,000hz, as this is covers most of the audible sounds people are most likely to encounter in everyday life. (Rolfe, 2009).

5.1 Properties of Sound A sine wave is produced by simple harmonic motion (SHM), where each vibration is repeated in equal time periods. They are known as pure waves as they produce a clear tone (Maltby, ‘02).

5.2 Frequency and Wavelength The frequency of sound is the number of cycles of vibration that occur in 1 second. (Maltby, ‘02 ). It is defined by the equation F = 1/t (1) where t is the period of time that it takes for 1 cycle to complete, in seconds. The more cycles per second, the higher the frequency. The wavelength is defined as the distance covered by one complete cycle and can be determined by the equation Wavelength = Speed/frequency (2). As frequency increases, wavelength decreases (Maltby, 2002 : 6).

5.3 Decibels

Figure 4 : Diagram Depicting waveform

The decibel (dB) is the unit used to measure sound intensity (Dangerous Decibels ‘09). It is a logarithmic scale due to there being such a wide range of intensities. On the decibel scale, the smallest audible sound (near total silence) is 0 dB. A sound 10 times more powerful is 10 dB. A sound 100 times more powerful than near total silence is 20 dB. A sound 1,000 times more powerful than near total silence is 30 dB (How Stuff works, 2009). Continuous Db

Permissible Exposure Time (mins)

85 88 91 94 97 100 103 106 109 112 115

480 240 120 60 30 15 7.5 3.75 1.975 0.9375 0.46875

Figure 5 : Table of permissible exposure times to various frequencies (Audiology Awareness) AFFA - Adjustable Frequency Fire Alarm

Figure 6: Common Db ratings.

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6.0 Audiograms and Interpretation An audiogram is a chart of a person’s hearing ability (Audiology Awareness, 2009). It compares dB with frequency and looks at people different levels of hearing across the spectrum. People are tested and points plotted on the graph to show where they have the most hearing ability and loss. Both the left and right ear are plotted on the same graph. Examples and explanations of different audiograms are shown overleaf; however, it must be kept in mind that everybody’s audiogram is different. The diagram below depicts the ‘hearing banana’. The banana refers to the different frequencies and decibels at which letters are pronounced. Audiograms show the softest level at which a sound is individually perceived. This is also referred to as the hearing threshold (Siemens, 2009). Ski-slope hearing loss (high frequency) is shown on this diagram and is the most common hearing loss. (Rolfe, 2009) The example audiogram slopes down from 20dB for 250Hz to 80dB for 4000Hz. This means that a standard fire alarm, according to BS 5446-3, which emits sound at 3100Hz at 75dB, would not be as effective as a lower frequency alarm for a person suffering from high frequency hearing loss. The frequency axis of an audiogram is logarithmic. People ommonly hear between 250-8000hz. (Deafness Research) the scale gives higher sampling at the frequencies we hear most often.

Figure 7 : Diagram depicting levels of hearing loss and the Hearing Banana AFFA - Adjustable Frequency Fire Alarm

These 3 example audiograms show various different types of hearing loss. Reverse ski-slope hearing loss, cookie-bite hearing loss, and noise induced hearing loss. Reverse ski-slope is rarest, affecting around 3,000 people in the US and Canada (Hearing loss helps, 2009). It lessens peopleâ&#x20AC;&#x2122;s ability to hear low frequency tones. This will be important later on, as research into fire alarms show low frequency alarms to be better than standard 3100Hz alarms. Cookie Bite Hearing loss affects peoples ability to hear mid-range sound. Consonants and vowels are hard to distinguish, however lower and higher pitched noise, such as the hum of cars on the road, or aircraft taking off are easy to distinguish. This hearing loss does have a reverse whereby the hearing loss is opposite. Common amongst people who have a profession exposed to sound, is noise induced hearing loss (NIHL). This affects certain frequencies of sound dependant on length of exposure, and causes the ear to be less astute. A construction worker for example, who operates a pneumatic drill for excessive periods of time, if unprotected may suffer from NIHL at around the 3-4 kHz range. Tinnitus may also occur at the same frequency as the exposure (Rolfe, 2009).

Cookie-bite hearing loss

Reverse Cookie-Bite hearing loss

Reverse Ski-Slope Hearing loss

Figure 8 : Diagram depicting audiogram of person with mild bilateral low frequency conductive hearing loss.

Appendix A shows Audiograms of various people who were happy to supply their results. AFFA - Adjustable Frequency Fire Alarm

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7.0 Hard of Hearing There are 4 main levels of hearing loss: mild, moderate, severe and profound. It is important to clarify the different terms surrounding deafness. Somebody who is said to be “deaf” would fall in the profound range whereby they have little to no hearing, with the quietest sounds they can hear being at an average of 95 dB (RNID, 2009). People who fall into mild, moderate and severe are said to be hard of hearing. There are also people who are “deafened,” which refers to people that have lost a degree of hearing after being born.

7.1 Conductive Hearing Loss Conductive hearing loss occurs in the outer and middle ear and is likely to cause low-frequency hearing loss (Rolfe ‘09). It is usually caused by a number of different factors (Bupa Foundation, 2009) : • Perforated ear-drums • Collection of fluid in middle ear (otitis media with effusion) and infection (acute otitis media). • Damage to the ossicles, for example by serious infection or head injury.

7.2 Sensorineural Hearing Loss Sensorineural hearing loss occurs in the inner ear. It affects the cochlea and the pathway of sound to the brain. This type of hearing loss distorts sound as well as making it harder to hear. (Rolfe ‘09). Common causes include (Bupa, 2009) : • Presbyacusis • Noise induced hearing loss (NIHL) • Infections, such as meningitis • Menieres disease & Tinnitus • Cancer treatments (Chemotherapy) • Ototoxic Drugs. • Acoustic neuroma. A benign tumour affecting the auditory nerve causing deafness and tinnitus. Presbyacusis is the most common reason for sensorineural hearing loss and caused by the part of the cochlea that interprets high frequency noise being closer to the middle ear. Consequently this means sound reaches the high frequency area of the cochlea first and therefore causes it to diminish at a faster rate. People over the age of 60 often suffer from this type of loss due to simply being alive longer, meaning their ears have been exposed longer to different sounds. (Rolfe ‘09).

7.3 Menieres Disease Meniere’s disease is a long term progressive disease that affects balance and the inner ear. Symptoms of having the disease are hearing loss, tinnitus and vertigo. It usually affects around 1 in 2000 people and most frequently occurs between the ages of 20-50. (Menieres Society, 2009). The causes of Menieres are unknown, but there are a number of factors that are probably involved in its development. Factors may include (Menieres Society, 2009): • Increased pressure of the fluid in the endolymphatic sac in the inner ear. • Viral infections. • Heriditary/family history. • Metabolic disturbances involving Sodium and Potassium balance of inner ear fluid.

AFFA - Adjustable Frequency Fire Alarm

7.4 Tinnitus Tinnitus is the perception of sound in the absence of any corresponding sound (British Tinnitus Association, BTA). It is ringing, buzzing, humming in the ears that do not come from any outside sound. It can occur at any age and one third of all adults report some Tinnitus (RNID, 2009). Exposure to loud noise is usually the cause of Tinnitus, and around 10% of the population have it all the time. (BTA). Tinnitus will usually occur at the same frequency in which a person has their lowest hearing ability. (Rolfe ‘09).

8.0 The Perception of Sound Sound can be perceived in many different ways. Meanings can be associated with it, and perception of noises are roughly the same for every human being. There are four main ways in which sound can be perceived (Treasure ‘09). Most of the sound around us is accidental and unpleasant and as humans we have developed a habit of suppressing sound. For example walking down the street, whilst chatting. There will be many noises happening, but we are able to blot out the particular ones we do not want to hear and focus on what our friend might be saying. Physiological - Alarming sounds affect Quartozole levels which affect the fight-flight hormone, sounds affect hormone secretions all the time, but also heart rate, breathing and brain waves. Oppositely, we are not just affected by unpleasant sounds, wave sounds at approximately 12 cycles per minute is soothing, as tis is roughly the frequency of a breathing sleeping human, as well as the association with being holiday and stress -free. Psychological - Music the most powerful sound that affects emotion. Certain pieces of music evoke emotive reactions. Natural sounds once again can affects us dramatically. Birdsong, for example, offers reassurance because over 1000’s of years we have developed to recognise that birds singing means things are safe, it is when they are not singing there is a problem. An alarm sound is harsh and rarely heard, giving rise to more intense reaction when it is heard. Cognitively - Relating closely with Phsyiological reasoning, we are affected cognitively by our brains having a small bandwidth for processing auditory input. Which is why we are unable to hear two people at once. A further example is loud offices and background noise which affect production levels. In terms of developing an alarm system, enough emphasis must be given on the sound to make sure it is heard clearly above an other noise. Behaviourally - Sound can affect people behaviour, the pitch and rhythmic patterns for example can force people to act in certain ways. For example, faster music affects driving speed and the sound of drilling or an alarm causes people to move away from unpleasant sound. The way in which sounds affect people and the psychology behind it are crucial to the development of understanding an alarm system and what sound it must produce in order to provoke the desired reaction.

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8.1 Sound flow model. Using the sound flow model, reason as to the effect a sound can have can be ascertained. By considering each stage from drivers and filters through to the outcomes, the necessary sound can be reasoned. In the case of the fire alarm, the main outcome is required to be one of alertness and identification of something â&#x20AC;&#x2DC;out of the normâ&#x20AC;&#x2122;. For this, there must be changes as previously discussed, in the 4 ways our brain is affected. For changes in state of the brains activity to occur the drivers of the sound are likely to be the frequency and time period of the noise as well as the volume level. Within the filters stage, the sound will be driven by function (recognition of sound being alarming), with the outcome affecting all areas of perception, but in particular the physiological area of the brain, meaning adrenaline kicks in faster and more immediate response to danger is evident.

Time

Drivers

Pitch Texture Density Dynamics

Filters

Functions Environment People Brand Values Physiological

Outcomes

Psychological Cognitive Behavioural

Figure 9 : Sound Flow Diagram

AFFA - Adjustable Frequency Fire Alarm

9.0 Hearing Aids A questionnaire carried out and documented in “Waking effectiveness of alarms” (Bruck ‘07) shows of 44 people questioned 95.5% people said they always remove their hearing aids before going to bed, whilst 4.5% said they sometimes keep theirs in and 0% always keep theirs in. This suggest that if the alarm was to be one that wakes the user, considerations for waking them must revolve around what they can hear without any aid. Oppositely, Bruck states that research shows that when awake and at home 37% of the 44 people questioned never wear their hearing aids at home, 35% sometimes and 28% always. From this research it must be considered that whether awake or asleep it is the never certain if the user is to have their hearing aid in or not. For this reason, any design will assume that the user does not have their aid, that way ensuring regardless of whether they do or do not they will always be alerted. There are two main types of hearing aid, analog and digital (Watson ‘09). Both consist of a microphone which picks up sound from the environment and converts it into an electrical signal, which it sends to the amplifier (with digital aids also containing a computer chip). A receiver/speaker changes the electrical signal back into sound and sends it into the ear. Then those impulses are sent to the brain. The difference being that an analog aid, pick up all of the surrounding sound and amplifies it equally. These are best used in cases of equal hearing loss across all frequencies, whilst a digital aid, after an audiology examination can be calibrated to boost specific frequencies for people who have certain types of hearing loss, such as ski-slope.

Figure 10 : Diagram showing parts of hearing aid.

Figure 11 : Diagram showing Cochlea Implants..

With this understanding, when running user group sessions it will be possible to understand what people are talking about and how having a hearing aid helps that particular person. Understanding audiograms and why particular people need certain aids will also be useful during the design stage. There may also be design opportunities to include the hearing aid into potential solutions.

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10.0 Ways of alerting people Research carried out by the US national fire protection agency; found that a low frequency fire alarm of 520Hz square wave was the most effective way of waking people whilst sleeping. Tested were 44 people defined as hard of hearing. (Bruck, ’07) Whilst asleep, the various alarms were played over a course of time. Each alarm was played for 30 seconds and then switched off for 30 seconds. If the person had not woken up, then another 30 seconds at a higher intensity would be added until they did wake up, if at all. Intensities ranged from 55dB to 95 dB with 75dB being the benchmark. For strobe lights, the light and flashing intensity was varied, all above the BS 5446-3 of 15 cd when viewed from an angle of 0°.

Waking Device

% waking at or below benchmark dB

% waking above benchmark dB

400Hz Square Wave 520Hz Square Wave 3100Hz Square Wave Bed Shaker Pillow Shaker

86.5 91.7 56.3 80.0 83.4 Awoke at level A 27.0

8.1 8.3 28.1 8.6 13.3 Awoke at Level B 29.8

Strobe Light

Slept Through 5.4 0.0 15.6 11.4 3.3 43.2

Figure 12 : Table show waking benchmarks of various people.

From this research, it is clear that the 520Hz signal is the best, with the strobe lighting and bed shakers close behind. It can be reasoned that although the 520Hz signal have proven significant, there is room for improvement. From this research it can be deduced that for most people this low pitched sound may be better at waking them but is not one they can identify with fire. The shriek of a normal alarm is what raises people’s alert level. Knowing that an alarm producing sound is the best way to wake somebody, a product that allows userspecific frequency settings is an obvious solution. If a person has moderate hearing loss in the higher frequency range (NIHL, reverse-ski-slope), they may not need an alarm as low as 520Hz, however may not be able to hear a standard 3000Hz alarm. The idea of having an alarm in which the user sets the frequency they can identify best with is one that can be drawn from this research and is the area for exploration.

AFFA - Adjustable Frequency Fire Alarm

11.0 Current Alarm systems Alerting devices can inform a person with hearing loss of important sounds through visual, olfactory, auditory or vibratory outputs (Valente ‘00) and at present, there are many alerting devices for Deaf and Hard of hearing people on the market. When considering product placement alarms for deaf and hard of hearing people are most needed in the home. In public places or at work, there is likely to be indication of a fire if one breaks out (people leaving the building). When at home, a deaf or hard of hearing person may either have a system for any alerts, such as the doorbell, telephone etc, or may simply rely on another individual in the household.

Fire Alarm Strobe light

RRP - £113.85 Supplied by RNID

Power Junction Vibrating Pad

Alarm

Vibrating Pad

RRP - £39.13 Supplied by Connevans

Clock RRP - £43.99 Supplied by RNID Vibrating Pad

Figure 13 : Images showing 3 different alerting systems.

Despite research showing that a 520Hz wave signal is the best for waking hard of hearing people, these products, from the RNID and Vibralarm, still have an alarm that emits at 3o00Hz. The RNID system (top) has a bed shaker, light and normal fire alarm that are all linked together to alert the user of fire. The Vibralarm clock, is a standard alarm clock with a vibrator added to shake the user awake. The wristwatch is connected to a system that is able to alert the user of any situations. The RNID smoke alarm system currently retails at £113.85. This is a high price for what effectively is a normal smoke alarm that triggers a shaking device and strobe light. Both the Vibralarm and wrist watch are medium proced at £39.13 and £43.99 respectively (Connevans ‘10). The price is reflected in the fact that low amounts are produced and sold. People feel that the products are obtrusive and do not want them. The main target market as defined by the RNID for their products are elderly homes that will buy in bulk and need of the correct equipment. Hard of hearing people are not likely to feel the need to buy one of these products without professional recommendation.

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The Lifetone HL Bedside Fire Alarm and Clock shown to the left is currently the only product on the market that emits sound at a frequency of 520Hz. Though proven to be the best alerting signal, it is one of which, if you are not used to will sound confusing. From the research it is evident there are more types of hearing loss that ski-slope only, meaning not all people are hard of hearing in the high frequencies. These would then be excluded from this product. People do not want to have a product that labels them. While specialised detection and alarm devices are available, there is a not a lot of information about how to obtain them. In addition, these devices often are highly priced (FEMA,’99). This is a problem that needs to be resolved with all of the current products. The proposition of a fire alarm that allows the user to change its frequency to suit their specific hearing capability is the direction for the rest of this project.

Figure 14 : Image showing Lifetone HL Bedside Fire Alarm and Clock (Lifetone Store)

In Appendix B there is a full breakdown and comparison of different products as outlined by Kevin Taylor (RNID Technical Evaluation Manager) in his article “Stay Safe, Sleep Easy”.

AFFA - Adjustable Frequency Fire Alarm

12.0 Target Market Defining the target market is important to gain understanding of who the product is to be aimed at and what user requirements will be needed in the design. Ultimately, as a fire alarm is a safety critical product and the design in question is of an inclusive nature it would be hoped it would be accepted into every house hold. However, this is unlikely to be the case and therefore a more specific market place needs to be reasoned. Professor Adrian Davis of the British MRC Institute of Hearing Research estimates that worldwide the total number of people suffering from hearing loss of more than 25 dB will exceed 700 million by 2015. (Hear it, ‘09). With the RNID being the main outlet for sale of the product the immediate target market will be of those who already have access to the organisation. Over 9 million people in the UK are estimated to be deaf or hard of hearing (RNID, 2009) and it is these people who will be the main target group for the product. Other considerations as to who the product is to be aimed at include those of people who are not hard of hearing but looking to purchase the product for those who are. Elderly people, for example, may not have the means to understand or source a specialised alarming system (Gwynne ‘07) or parents who have hard of hearing children may need to purchase the product for their son or daughter. In the UK, there are around 25,000 British children aged 0 to 15 are ‘deaf or hard of hearing’.Of these, 8,000 are severely or profoundly deaf (RNID ‘10). There are also specialist agencies who would look to purchase the product. As it is to be a system, government and private agencies who run care and elderly homes may also look to source the alarm. To clarify Primary users - Secondary users -

The deaf and hard of hearing community. Those who are exposed to the fire alarm, for example, parents of heard of hearing children, people who work in care homes etc.

Target Market -

The deaf and hard of hearing community. People involved with the RNID. People who are looking source specialist equipment for hard of hearing end users.

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13.0 Personas Personas are an important aspect of design, they allow insight into the potential end user and target markets feelings are towards various aspects of life. They allow for closer engagement as to the people who are being designed for and personally, provoke empathy towards the people in mind. With the information gathered from real-life people as to how they interact with certain products, their feeling about the environment they’re in and their opinions on current systems they have or what they would like to see in the future, the ‘voice of the customer’ can be transferred into design requirements for further development. A wide variety of personas have been established, in which examples are shown in Appendix C.

Eleanor Hickford

Tricia Barker

Pamela Jordan

Billy Laven

Karen Johnson

Tom Davis

Figure 14 : Image depicting people used when creating Personas

Ellie Hickford - 11, Profoundly deaf, Klipper Feil Syndrome. Tricia Barker - 62, Reverse Ski-slope Hearing Loss. Pamela Jordan - 67, Severe Hearing loss. Billy Laven - 22, Hard of Hearing. Karen Johnson - 48, Stroke victim, mild hearing loss in left ear. Tom Davis - 31, Father of 2, Billy aged 4 and Rosie aged 2, Rosie has severe hearing loss.

AFFA - Adjustable Frequency Fire Alarm

14.0 Streamlined Lifecycle Analysis Considering the products energy embodiment and consumption is an important area to realise when designing the new system. Analysis of the current RNID unit has been undertaken to determine the energy consumption throughout its life-time. This will be used as a basis to design from and improve upon when specifying the functions of the new design. Later, the final design solution will be analysed and the two results combined and evaluated.

Energy used to extract oil for plastic. Energy used in running tests of machinery.

Energy used to install home wiring.

SLCA Boundary

Energy used to manufacture 1 fire alarm.

Energy used to transport fire alarm from shop to home.

Energy used running product.

Energy used to dispose of product.

Manufacture & Extraction phase

Transport phase

Use phase

Disposal phase

Excess materials.

Maintenance of vehicles.

Change in usage of energy from 1.2W to 8.7W when activated.

Emissions that product may cause.

Figure 15 : System Boundary for RNID Fire Alarm SLCA

Reasoning behind analysing both the current system and the new system is to gauge the environmental impact the two have on their surroundings in terms of energy use. It is to reason whether battery or mains power supply is best for the new product and to compare the impacts to work out where the best saving would be. It is likely that a save in energy will mean a save in components and in turn this will reduce the manufacturing cost and have a positive impact on the both the environment and the manufacturing costs of the product. The embodied energy in material values have been obtained from Design & environment : Global guide to designing greener goods Gertsakis,â&#x20AC;&#x2122;01 and are there for specific values of the material that has been used. A standard value of 2000MJ has been assumed to calculate the PCB energy value. In this case 2000MJ.

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14.1 SLCA for RNID Fire Alarm Component

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

Main top w/blue button Main bottom Clear outer section Power junction Casing bottom Power junction Casing insert Power junction Casing top Battery cover RNID smoke alarm inner section Blue pull out instruction section Blue Side Button Two rubber feet All screws Battery Vibrating Pad top & bottom Vibrating Pad electronics w/wire (2m) Wire between base & fire alarm (10m) Main PCB Plug w/wire (1m) Wire between base & junction (1m) Fire alarm top Fire alarm bottom Instruction leaflet Spring Alarm plastic amplifier Black inner alarm casing Fire alarm PCB Box & Inner slip case Junction PCB Manufacturing & Extraction Total Transport Usage Disposal Total

Material

Weight (Kg)

Polypropylene Polypropylene Polypropylene Polypropylene Polypropylene Polypropylene Polypropylene Polypropylene Polypropylene Polypropylene Rubber Steel Polypropylene TPV Copper TPV Copper TPV Copper TPV Copper Polystyrene Polystyrene Card Steel Polystyrene Polystyrene Card -

0.0615 0.1765 0.0280 0.0225 0.0030 0.0210 0.0265 0.0265 0.0300 0.0015 0.0010 0.0115 0.3580 0.0540 0.081 0.0269 0.117 0.039 0.0712 0.276 0.089 0.0735 0.0245 0.0505 0.0265 0.0045 0.0010 0.0090 0.0105 0.0100 0.0410 0.0080 1.7806

Energy Embodied in Energy Embodied in Material (MJ/Kg) Part (MJ)

Route from factory 24/7 use time Landfill

80.033 80.033 80.033 80.033 80.033 80.033 80.033 80.033 80.033 80.033 75 32 55 80.033 100 125 100 125 2000 100 125 100 125 102.16 102.16 25 32 102.16 102.16 2000 25 2000

4.92 14.13 2.26 18.01 0.24 1.68 2.13 2.13 2.40 0.12 0.075 0.368 19.69 4.32 10.75 3.36 15.7 4.88 142.4 36.75 11.25 9.8 3.06 5.16 2.71 0.11 0.032 0.92 1.073 20 1.025 16 357.49 15 1704 2 2078.49MJ

Figure 16 : Expanded SLCA results for RNID Fire Alarm.

The table shows both the embodied energy for the RNID fire alarm and the energy it uses over a projected 15 year lifetime, the total is 2078MJ. In conclusion this analysis has lead to realisation of the current system to improved upons energy consumption but also to the amount of parts it has and whether or not they are all necessary in order to perform the desired operation. With this in mind, a Dewhurst and Boothroyd analysis was undertaken to question the validity of all the parts. This is shown overleaf and was the basis for the achievable part count for the solution.

AFFA - Adjustable Frequency Fire Alarm

15.0 Dewhurst and Boothroyd Analysis of RNID Fire Alarm To ensure the proposed new design is more environmentally friendly as well as easier to manufacture the analysis of the current RNID alarm looks at the parts of the product and asks 3 pertinent questions :1) During operation, does the part move relative to all other parts already assembled? 2) Must the part be of a different material from all other parts already assembly? 3) Must the part be separate from all other parts for assembly or dis-assembly? If the answer to any question is no that part becomes a candidate for elimination. The idea behind undertaking this type of analysis is that it will reduce the amount of parts the system needs to have in order to function. This will reduce environmental impact across a variety of different stages of the product life-cycle. With minimal parts the energy used to produce the product as well as the energy embodied in the components will be lower. This will lead to downstream savings at the transport and disposal stage. It also means that the manufacturing of the new solution will be as simple as possible due to a lower part count. From the analysis, which is shown in the Appendix, the RNID alarm part count is 42 and can be reduced to as little as 14 and still perform the same operation, this leads to a potential saving of 1.0516 Kg from 1.7806Kg down to a possible 0.723Kg. These are important considerations when defining how the product will work, be manufactured and affect the environment. Later in the report an SLCA of the proposed solution has been carried out to verify any improvements. The Full Dewhurst and Boothroyd Analysis is in Appendix D

Figure 17 : Images showing close ups of various parts of RNID Fire Alarm. AFFA - Adjustable Frequency Fire Alarm

26 27

16.0 Concept Generation Background information as to how people hear and insight into how deaf and hard of hearing people feel now means that concept generation can be deduced. In order to gain successful concept ideas a brainstorming session was undertaken with various hard of hearing participants. This session allowed mostly, key analysis into how they feel about current systems and it is from this new system ideas have been drawn up. Given the nature of the product as being one people want to have but never really want to witness working, unless indeed their house is on fire, the ideation stage is has been clarified by a General Iterative Technique (GIT) chart. The idea behind a GIT chart is that it has 5 levels, with level 3 being the realistic/achievable current or new design, whilst levels 4 & 5 indicate progressively more complex design solutions, and 1 & 2, stripped down versions of the level 3 idea. By completing this chart, all ideas can be clarified into categories of simple design through to the most radical. Ideas from each can then be drawn to gain the best solution from the user feedback.

Figure 17 : GIT Chart

16 concepts were generated that each had varying different degrees of complexity and necessity. Overleaf, these are categorised and distilled into which aspects are the most relevant, given the user research and the understanding gained into how the ear functions and responds. The best ideas were then narrowed down and if possible incorporated together. These have formed the final product outline, documented on page 32. The GIT Chart is shown in Appendix E.

AFFA - Adjustable Frequency Fire Alarm

17.0 Product Selection From the concept generation stage, 4 ideas have been considered to have the most potential and have been carried forward for further analysis. Shown here are the 4 potential concepts with reasoning as to which should be carried forward to for final design exploration. Appendix F shows the SWOT analysis for each of the chosen 4 concepts to determine the best for development. Appendix G shows sketch ideation.

Filtering Concept. Sound in bedroom is heard by using a filter.

This concept has great potential to fulfil the brief. Offering a waking alert, potentially with different frequency selection, together with likelihood of direct incorporation into the home, functioning in sync with household alarms.

Wireless system, whereby sound is relayed to bedroom through radio signal.

This concept, like the first offers good potential to fulfil the brief, by using varying frequency selection to cater for as many different hearing abilities. It will require two units to be produced, however with development has great potential.

Bedside device which hearing aids can be docked upon (See Appendix F for full details)

This system idea is one that would emit sound that would be highly specific to hearing aid users hearing abiltites. No setup would be required, the user could simply place their hearing aid upon it and it would emit at the sound they can hear best when they do not have their aids in. This system has great avenues for development, however, due to time restrictions is unlikely to be persued unless there is overwhelming feedback from users that it would be the desired solution.

Childs alarm that is characterised and can offer alert as well as integration into bedroom.

Idea targets a specific market and would allow hard of hearing children to become aware of fire safety. However, there are too many implications with designing a system of this nature. Children may think the alarm is a toy, and this may hinder their ability to take the product seriously. It would also not fulfil the inclsuivity requirement. A hard of hearing fire alarm needs to be as universal as possible. Figure 18 : 4 most potential design directions

AFFA - Adjustable Frequency Fire Alarm

28 29

18.0 User Research In order to justify the potential project direction of an adjustable frequency fire alarm a questionnaire was devised and distributed to both family and friends who suffer from hearing loss as well as hard of hearing clients of Crossroads Care, Havering and contacts that were made through attending the RNID Hearing Matters Conference 2009. In some instances it was distributed to parents of children who have hearing complications to gain feedback on the childs alarm concept in particular. The full questionnaire is located in the Appendix H of the report and the results are shown below. Of the 30 people approached 11 responses were gained. The questionnaire also looked at finding out about the target market, their type of hearing loss ( different types will give different concept feedback) and the reasons why people feel certain concepts would be better than others. It was decided that concepts, 1 and 2 would be grouped together for the questionnaire as they share similarities, it is only the method of alarm detection that is different. It was also decided that the best concepts for development as supposed to all of the ideas generated would be incorporated into the questionnaire so as not to overwhelm the person filling it in.

User

Concept Filtering/wireless concept Automatic dock tuning concept Child illumination of path alarm.

Average response

4.09

3.45

2.45

Figure 19 : Results of concept feedback questionnaire.

The results show universal appeal to one idea in particular, that of an alarm system that has a sound that is able to be set by the user, so that specific hearing capabilities can be met. The product selection page has discussed two ways in which these needs can be met (idea 1 and 2) and both can looked to be developed. The results are the ones that were expected. Through talking to people at the Hearing Matters, RNID it was already understood that people would like an alarm that sounds at various frequencies. The questionnaire now clarifies this information and allows for prototype development to begin.

AFFA - Adjustable Frequency Fire Alarm

19.0 Initial Development 19.1 Battery or Mains supply? With the SLCA completed a design decision can be made as to the powering of the AFFA fire alarm. Given that the nature of the product is one that is required to run 24/7 both battery and mains have their advantages and dis-advantages. Each way will use the same amount of energy over the products lifetime as the alarm will draw the same current regardless of power supply. The advantage of mains powering is that of constant power supply (no need to change batteries), however with mains comes the problem of electrical failure during a fire, in which case a back-up battery would be needed anyway. It is for this reasoning that batteries have been selected to power the product, changing the batteries and regular testing of the alarm system will have to occur more often, however the reduction in likelihood of failure during a fire is decreased. The use of rechargeable batteries is also a possibility, with long life lithium ion being the best candidate for long periods of use. This may change dependant on the prototype development.

19.2 Which type of sound wave? Waking Effectiveness of alarms (Bruck â&#x20AC;&#x2DC;07) experiments using square waves only, for that reason a test was devised to see which type of wave would be best for inclusion into a new system. The image shows the setup using a simple amplification kit, with various wave input coming from a waveform generator. The waves tested were a Sine wave, Square wave and saw-tooth wave. These waves were tested by listening to which one sounded more prominent when listened too at the same frequency and volume.

Figure 20 : Ampflication circuit used for testing different waveforms AFFA - Adjustable Frequency Fire Alarm

30 31

From the test it was determined that the best alarm sound should indeed be the Square wave. This is because this type of wave can be constructed from multiple sine waves at different frequencies. Sine waves added in addition to the fundamental frequency are called harmonics; a square wave has harmonics at odd multiples of the fundamental frequency. As higher harmonics are added, the result gets closer to an ideal square wave, which contains infinite harmonics. The diagrams below the 3 waves that were generated, all at a frequency of 2Khz. As well as the top right diagram indicating how Sine waves are added together to form Square waves.

Figure 21 : Images from Oscilloscope showing the three types of waveform & how Sine waves when added together can form Square waves.

AFFA - Adjustable Frequency Fire Alarm

20.0 Final Concept Following the research that has been carried out a final direction for the project has been ascertained. From this it has been deduced that the main area for concern will be that of an fire alarm that sits in the users bedroom and wakes them if they are sleeping in the event of a fire. The bedroom unit will be activated via information relayed from a Hallway unit. The information relay is essential as if the bedroom unit is the first to sense the fire the critical escape time has already been cut and the fire is already nearing the users sleeping area. With the feedback gathered on the current system the main avenues for development are thus, • • • • • •

Different frequency levels of audio output - so as not exclude any type of hearing loss. Hallway unit sensing fire that relays information to a bedroom unit. Option to have a less intrusive vibrating pad. The product must retail at an affordable price point. Intuitive to setup and understand how it works. Must wake the user, regardless of whether they keep their hearing aid in or take them out.

Figure 22 : Image showing final concept.

From this point two designs have been narrowed down for further investigation. • Design 1 - An alarm to be situated in the bedroom that listens to sound and determines if a regular household alarm is sounding and outputs various frequency noise to alert the user who may be sleeping. • Design 2 - An alarm which wirelessly communicates from the Hallway to the user bedroom unit and alerts with various frequency sounds, a vibrating pad and strobe light. Each of these designs have their advantages and disadvantages, these will discussed in the development section. AFFA - Adjustable Frequency Fire Alarm

32 33

21.0 Product Design Specification (Preliminary) At this stage it has not been determined whether the design solution will be that of the filtering alert system, or the wireless system. The PDS has therefore been written with both in mind. The specific points that need to be updated when the solution has been narrowed down through prototyping and user feedback will be addressed in the updated PDS on page 71.

21.1 Basic System Purpose 1. A unit to be placed in the hallway will detect any fire and send a signal to the bedside unit to sound and alert user. 2.Bedside unit is able to be set at various frequencies dependant on the userâ&#x20AC;&#x2122;s specific hearing loss 3. Give options to user to use any combination of sound, vibrating pad and strobe lighting.

Hallway unit

Bedroom unit

Sound filtering or wireless detection, yet to be determind

Various frequency output with inclusion of strobe light and vibrating pad.

21.2 Performance 4. The fire alarm has to function when needed too. A failure to do so may lead to fatality. 5. Must allow user to dial in frequency according to their specific hearing loss. 6. The frequencies that the alarm can be changed to are yet to be determined, however it is thought they will be across 8 bands. 420Hz, 520Hz, 800Hz, 1200Hz, 1500Hz, 2000 Hz , 2500Hz and 3100Hz. (420 & 520 based on findings from Waking effectiveness of alarms documentation). This will be concluded by prototype development. 7. All sounds waves are to be square waves. 8. Interface options are to be - latching on/off switch for strobe light activation. Dial that allows for toggle between frequency of sound. 9. Product is to be battery operated by a 9v supply. 10. When battery installed product is automatically on. 11. Installation possible without use of electrician. 12. Must function with combination of sound, strobe lights and vibrating pad, as the user wishes. Strobe to be actuated by latching switch, whilst vibrating pad by removal from system. 12. Main cover section is to be manufactured from PS. 13. Materials, finishes and colours must not fade from exposure to light for up to 10 years. 14. Front cover section is to snap fit to back cover section of main unit. 15. To test product, test button must be depressed with a minimum force of 15N for 5 seconds until sound is heard from both alarms. 20. Test button to be circular with diameter of 25mm. Must indicate it is test button. 21. Angle of press to be 90 degrees perpendicular to face of test button. 22. Casing must withstand impact force of minimum 200N to withstand being dropped. 23. Ports for vibrating pad and strobe lighting connection must be easy to locate and attach components. AFFA - Adjustable Frequency Fire Alarm

24. Strobe lighting to have flash rate of 60 per minute. 25. Frequency to be changed with use of dial with indication of which frequency to be evident in instructions.. 26. Nature of design will allow for either beside table use or connection to wall. 27. Product to sound at 90db. 28. Hallway unit and bedroom unit to each be able to be set at a frequency the user requires. 29. Alarm is to sound for a duration of 1 second and then be off for 1 second before sounding again, creating alarm tone. 30. Strobe unit to be Delta design MS1x12/1. 31. Vibrating Pad to be Connevans 6v dc pillow vibrator.

21.3 Product Life Span 32. 10 years +. A fire alarm is a product that is never going to be â&#x20AC;&#x153;outdatedâ&#x20AC;? its main purpose is the detection of smoke.

21.4 Service Life 34. Powered by 9V battery. Alarm is to beep/flash/vibrate once every 5 minutes when battery is low, alerting user. 35. Product is to be on 24/7. Batteries would be expected to last 3 months minimum in each unit. Testing regularly is recommended. 36. Dial switch to change frequency is expected to be used less than 5 times over product lifespan. Once the emitting frequency is set, it will not be altered often. 37. Strobe light switch expected to be used less than 5 times over product lifespan. Once user has determined whether to have it on or off, it will generally stay that way over life time. 38. Vibrating pad connector, expected to last for product lifetime and bed used minimum two times a day, once to plug in at night and then to unplug in the morning.

21.5 Ergonomics 39. Products buttons, dial and battery changing section to accommodate for 5th - 95th percentile anthropometric data. 40.Simple, easy to use interface is essential. Consumer must be able to easily change frequency of sound. 41. Buttons and dial to be evenly distributed. 42. It should be assumed that the users will include people with low technical ability. This will have to be considered in both the design of the product and the writing of the instructions. 43. Language used must be clear and concise. 44. Installation must be easy, directions for use and set-up straight-forward and simple.

AFFA - Adjustable Frequency Fire Alarm

34 35

21.6 Environment 45. One unit is to be situated in the Hallway. 46. One unit is to be situated in the Bedroom. The bedroom unit is to sound at 90 Db and to be placed a minimum 1m away from the bed and a maximum of 15m. 47. Stored in box during transport, and POS, until situated in home of user. 48. Heat proof wires should be used, ensuring function if a fire were to occur. 49. Operating temperature : 10 °C - 60 °C 50. Operating humidity: 10 %- 100%

21.7 Quality and Reliability 51. It is not a product that is going to have use every day, in fact it is a product you want to have and never use, however if a time ever did come whereby it needed to be used, 100% reliability would be expected.

21.8 Manufacturing Cost 52. Must be kept as low as possible, the low cost of the product can be passed onto the consumer and the product will be more accessible than current specialist models. 53. £5- £20. At present on a rough estimation can be made as to overall price of product manufacturing. Dependant upon which system functions the best the Manufacturing cost will be revised after the prototype stage.

21.9 Market Price 54. Retailing price to be between £9.99 and £49.99, once again this will determined by the manufacturing cost, which as of yet is not obtainable, this will also be reviewed in the PDS update. 55. Products are to be subsidised to user by RNID.

21.10 User & Target Market 56. Primary users : Deaf & hard of hearing people. 57. Secondary users : General population. 58. Target Markets : The 9 million people in the UK are deaf or hard of hearing. Caring and elderly homes. Residents of the UK Government fire awareness schemes Fire services

21.11 Marketing Information 59. To be marketed through RNID solutions catalogue. 60. Potential distribution through government fire safety schemes.

21.12 Manufacturing Volume 61. Initial run of 1,000. Distributed to deaf and hard of hearing people via the RNID.

AFFA - Adjustable Frequency Fire Alarm

21.13 Weight and Size 62. Exact weight is yet to be accounted for. 63. Must be of a weight that allows stability.

21.14 Materials 64. Must make sure components where possible are made from fire retardant material. 65. Product main casing will be made from PS, easy to manufacture and readily available. 66. Buttons and dial to be made from PS 67. Vibrating Pad casing to be made from PP 68. All other components are electrical.

21.15 Aesthetics, Appearance & Finish 69. Essential to market and profitability of product. Clinical looking products do not attract attention. Product to have white main body section to allow familiarity as to the product being alarm, with blue sections to reflect colours of RNID branding. 70. Design must be attractive and make people not feel as though they are buying a specialist alarm.

21.16 Testing 71. Testing of reliability of product is essential. Product to be tested in users home on a regular basis (once a month). 72. Product not to be distributed before passing safety and functionality tests. 73. Alarm must have a test button that allows the user to check the sound they have their alarm set on.

21.17 Standards 74. Must be in accordance with BS 14604:2005 Smoke alarm devices. 75. Must be in accordance with BS 5446-3:2005 Fire Detection and fire alarm devices for dwellings – Specifications for smoke alarm kits for deaf and hard of hearing people. 76. All electronic components to be sealed correctly in accordance with European Standard EN 60529:1992, Degrees of Protection Provided by Enclosures. 77. Compliance with Restriction of the Use of certain Hazardous Substances in Electrical and Electronic Equipment (RoHS), EU Directive 2002/95/EC. 78. Compliance with Waste Electrical and Electronics Equipment (WEEE). European Directive 2002/96/EC.

21.18 Patents 79. Patent searches for “ adjustable frequency hard of hearing fire alarm” and “variable frequency fire alarm” returned no conflicts of technology use. More in-depth research is required to make absolutely sure no conflicts occur.

21.20 Product Disposal 80. PS & PP used must be able to be separated easily for faster recycling processing. 81. Parts must be kept to a minimal with Boothroyd & Dewhurst analysis theory having been undertaken theoretical part count is 14. This will be reviewed upon prototype completion. AFFA - Adjustable Frequency Fire Alarm

36 37

82. Electronics are to be removed from PCB before disposal.

21.21 Safety 83. Product must ensure the safety of the user as its number one priority. It must function every time and give people more time than usual alarms to get to safety. 84. Waking of user is expected to occur within 30 seconds of alarm going off.

21.22 Installation 85. Product is to require no outside help for installation. 86. Placing the batteries in the alarm is to be what turns the system on. 87. Product can be stood on flat on a surface or hung on the wall. 88. Attention must be given to Instruction manual, end users may need larger font and clear diagrams.

21.23 Maintenance 89. To maintain the products function check the batteries once a month.

21.24 Packaging & Shipping 90. Product is to be packed in a box together with polystyrene protection and instruction leaflet.

21.25 Competitors. 91. Competitors are shown in Appendix B. The Bellman B1460 and RNID smoke alarm are the main product competitors, however none offer varying frequency output.

AFFA - Adjustable Frequency Fire Alarm

22.0 Electronics Development From the Final Design outline section on page 32 it can be seen that two routes for project development have been stated. The two main differences between the systems are that one uses both an analog and digital approach to the solution and one digital only. Both have been undertaken to establish which is better for allowing one alarm situated in the hallway to interact with another in the bedroom, allowing for a varying frequency output. The first solution for prototyping and evaluation was that of the system that includes both analog and digital components. Varying Frequency Output

3o00Hz

Household Fire Alarm

Sound filtering allows alarm to be heard

Adapted fire alarm system

Figure 23 - Alarm that listens for sounding household alarm

22.1 Sound Filtering In order for this type of system to work, sound must be filtered by a microphone and determined to be the alarm signal only and not a differing noise from the surroundings it has been placed in. Before an alarm system can be setup to filter the sound, the frequency at which a household alarm is emitting at must be determined.

Figure 24 : Testing Frequency of household alarm.

Figure 25 : Scope Read-out of household alarm frequency.

The images above show a standard household alarm being tested for the frequency it emits at. The scope readout proved inconclusive. The frequency of the household alarm was resolved by using a frequency generator and an amplifier to audibly listen for when the generated square wave sounded the same as the alarm. At this point the alarm was thought to be around 2.8kHz - 3kHz. To prove the filtering system a success the household alarm was adapted using a PIC to emit at 3kHz only. AFFA - Adjustable Frequency Fire Alarm

38 39

23.0 Filtering Alarm System 23.1 Various types of filter Both Band-pass and low-pass filters were considered for inclusion into the system. It was decided that eventhough the frequency that needed to be filtered was 3kHz (which is considered as being low) the best solution was to be a band- pass filter. This is because sounds either side of the centre frequency can be filtered out and with a small bandwidth, the filter can be fine tuned to hear 3kHz and no other sounds.

23.2 Low-Pass Filtering A low-pass filter is one that passes low-frequency signals but attenuates signals with frequencies higher than the cutoff frequency. This means that if the cut-off frequency were to be 3Khz, everything beneath that would be picked up by the filter. A test was carried out using a Maxim 293 chip to view how a low-pass filter works.

4. Figure 26 : Low-pass filter results

1. Shows the low-pass filter at 722Hz allowing the signal through. 2. At 1.08kHz the filter is beginning to start as the amplitude is reduced. 3. At 1.3kHz, the amplitude is again lessened 4. At 2.15kHz is at its continuing to become lower and at 3Khz, it is a straight line, indicating 3kHz has been filtered out. Before carrying out this experiment it was reasoned that if a low-pass filter can be set at 5Khz, 3kHz will easily pass through, however upon completion, it was understood that a low-pass filter would not be as good as a band-pass as the frequencies below 3kHz can also be heard, it is not specific enough. AFFA - Adjustable Frequency Fire Alarm

The differences between filters can now be understood as experiments have shown an inconclusive way of achieving the final goal, it is for this reason that band-pass filtering was then investigated. When dealing with filters there are various different types, within both low-pass and band-pass, these include Butterworth, Bessel and Chebyshev. Each of these filters can have different orders, with the higher orders being the more specific at the point where the passband meets the stopband (a more defined filter point).

Figure 27 : Low-pass filter set-up.

Figure 28 : Graph showing increasing orders of filter.

23.3 Band-pass Filtering Band-pass filtering works by filtering out all frequencies above and below a certain mid-point. This means that detecting a 3kHz alarm from the hallway will be easier than using a low-pass due to being able to set the filter so that it does not hear anything above or below the centre frequency. At this point the use of an 8th order Butterworth Band-pass filter was used in the form of a Max 274 chip.

Figure 29 : Max274 Band-pass filter.

Use of the supplied Maxim software allowed calculation as to resistor values that were to be used to externally control the filter, by entering a centre frequency of 3kHz, the software was able to calculate the necessary resistors. After experimentation with this chip, it was deemed that for the application of simply filtering 1 household frequency of 3kHz the 8th order filtering was not necessary. Fine tuning the chip to respond only AFFA - Adjustable Frequency Fire Alarm

40 41

Hz Fb w+ Fs = 3 w+ .1k = Hz 3.3 kH z

3k Fc =

Fs w Fb - = 2 w- .5k = 2 Hz .8k Hz

to 3kHz, with such a tight filter of between 2900Hz and 3100Hz was one that was too complex for the given requirement. However, using the software did make the understanding of how the filter was working easy to understand. The graph below demonstrates the pass-band at which the filter was able to operate between.

Figure 30 : Max274 Band-pass filter graph as calculated by Maxim Software

23.4 Further Band-Pass Experimentation After experimenting with the 8th order max 274 chip and not finalising a solution, a different approach was undertaken. The development of a circuit that uses op-amps with calculated resistor values to create a lower order band-pass system was the new direction. This solution was successful in allowing only 3kHz to pass through the filter and determine whether the alarm should sound or not. It was considered at this stage to prototype a Twin-T notch filter to oppose the band-pass filter and include both in the circuitry to ensure that the filter was only passing 3kHz through, by equating the state of each filter (the band-pass being high upon incoming 3kHz signal and the Twin-T notch being low) however, it was decided unnecessary as the use of PIC coding could allow a sampling time to determine prolonged exposure to 3kHz and decide it was an alarm sounding or just an accidental noise of the same frequency.

Figure 31 : Band-pass filter setp using Op-amps AFFA - Adjustable Frequency Fire Alarm

kH z

4.1

2.2 k

3k Hz 3.5 kH z

2.8 k

Figure 32 : Op-amp Band-pass filter oscilloscpe readings

1. Shows the band-pass filter at 2.2kHz not allowing the signal through. 2. At 2.8kHz the filter is beginning to allow the signal through. 3. At 3kHz, the amplitude is at its peak. 3kHz sound is being let through. 4. At 3.5kHz the signal being allowed through by the filter is beginning to be reduced. 5. At 4.1kHz nearly no sound is being passed through the filter. With this solution being the better of the two filtering systems for use, the development of how the varying frequency output must now come into place. It is at this point a PIC is included into the design to allow code to be written that will be triggered from the high state it receives when a 3Khz signal is input via a comparator. The schematic for the band-pass filter system, along with calculations undertaken is in Appendix I. AFFA - Adjustable Frequency Fire Alarm

42 43

24.0 Component Development With a filter operating at 3kHz, it was expected when testing the household alarm that it would hear the sound and react by alarming aswell, however, this was not the immediate case. When testing a household alarm to see if the filter circuit would sound, it had no reaction. In order to complete the POP prototype, an alteration to the house hold alarm in question was made. The schematic for these changes made are shown in Appendix I.

Figure 33 : Altered House Hold Alarm system

As well as the inconclusive frequency testing of the household alarm, discussed earlier, It is thought that another reason the filtering system was unable to hear the household alarm sounding, was because when the alarm goes off it makes a beeping noise and that beeping noise was too short for the PIC in the filtering section to interpret as the alarm sounding. The PIC chip within the filtering section was setup to listen for 2 seconds, to determine if it was the alarm sounding rather than just a noise of 3kHz, which potentially could be something like a door slamming, where as the alarm was beeping for around 1 second, then turning off for 1 second, before beeping for another second and so on. This meant that if the PIC was setup to listen for a one second clip of 3kHz, it could potentially be interfered with by other sounds, it was for this reason that the alarm was altered to make the same frequency of sound but at a longer interval. This proves the principle of the prototype and gives success to this type of system.

Figure 34 : Final POP with household alarm now activating second alarm system. AFFA - Adjustable Frequency Fire Alarm

25.0 Programming Development - Flow Charts For this system to function correctly, two PIC 16F28 microcontrollers were used. 1 in the house alarm section of the design (sending section), and one in the filtering section (receiving). Below are the flow diagrams used when developing the coding for each section. The Coding for the alterations made to the house hold alarm is shown in Appendix J, whilst the coding used in the filtering section of the prototype is shown in Appendix K.

No No Has Test Button being Pressed? / Fire Detected?

Is 3kHz alert sounding?

Yes No

Yes Output 3kHz square wave sound

Has 3kHz been sounding for 2 seconds? Yes Output 520Hz Square wave sound.

Figure 35 : Flow Chart of Coding used to alter existing alarm sound duration.

AFFA - Adjustable Frequency Fire Alarm

Figure 36 : Flow Chart of Coding used to listen to alarm system and output a 520Hz Square wave.

44 45

26.0 Frequency Testing The output frequency of the filtering alarm section has been set at 520Hz only. Although stated that the output will be varying, it was deemed unnecessary for this prototype, as it was just to prove that a sound can listened for, heard and filtered, with a different output. The code for varying frequency output has been developed and included in that of the wireless proof of principle prototype.Below is the oscilloscope readout-out checking that the alarm is sounding at 520Hz.

Figure 37 : Image of PCB output being checked.

Figure 38 :Oscilloscope reading of output.

26.1 Distance Testing Given that the system uses a microphone to detect incoming sounds, with the alarm amplifcation at maximum, a distance test was carried out, to see how far away the hallway unit could be from the bedside unit. The distance that was acheived, before the prototyped no longer worked was 60cm. This distance is not one that meets the criteria set in the PDS, that information is to be sent from one room and received in another. Below are images demostarting the distance test. It is further discussed in the evaluation of filtering solution section.

Figure 39 : Images of distance testing. AFFA - Adjustable Frequency Fire Alarm

27.0 PCB Development When developing PCB designs various different iterations were needed to be undertaken in order to get fully functioning prototypes. The components used in the circuitry are not necessarily those that would be used at the point of manufacture. It has been realised that at the point of manufacture, there may be smaller better ways of completing the same task. For instance, the use of surface mount components, and in the case of the filtering circuit a quad op-amp, instead of 4 op-amps. The PCBs developed only prove the working principles behind the prototyping of the design, further investigation as to components along with liaison with specialist electrical engineers would govern the outcome of the final fire alarm design. The circuit boards were designed to be kept as compact and as minimal as possible to echo that of the size of a fire alarm. With a regular house hold fire alarm being no more than 200mm x 200mm x 50mm including outer casing the circuitry was designed to fit within. The PCB development for both systems is shown in Appendix L.

Figure 40 : Image of all PCB development undertaken to complete filtering system POP

AFFA - Adjustable Frequency Fire Alarm

46 47

28.0 Evaluation of filtering system prototype. The concept has been evaluated across various different aspects, including the most important from the PDS and problems that have arisen during the prototype stage.

28.1 Usability The prototype does address usability issues that were surrounding the current RNID system. The POP requires only the insertion of batteries into both units to gain a fully functioning system. This is unlike the RNID current system which requires various plugging in of components and an overly complicated setup process. As the prototype has not been developed with a changing of frequency alarm at this point, the usability of this feature cannot be determined, this will be covered in the next development process stage.

28.2 USP A big advantage of a system of this nature, is that there needs to be no purchase of specialist equipment. With a household alarm already in place in a home just the receiving unit could be purchased, which would listen to the already install unit, hear it sounding and then alert the hard of hearing user at whichever frequency is best for them.

28.3 Price Point The fact that no rewiring or specialist alarm system needs to be installed means that the only part that would need to be purchased would be the receiving unit, meaning the price of the product would be low. How low would be decided by the components that would be used in a final product, the total cost of the materials used in the POP totalled to be ÂŁ4.50.

28.4 Performance Although functioning, the one main area for concern with performance is the range of the system. After testing to find the distance at which the filter no longer hears the household alarm system the result was around 60 cm. This is for a variety of different reasons 1. The Volume level of the alarm, although loud, past a certain point the microphone no longer hears it. 2. The sensitivity of the microphone. The mic component used to detect the sound could be of a more sensitive nature, this would allow the sound to filter through easier. 3. The fact the system was controlled by internal resistors which decide sensitivity of the comparator, which allows the pic to receive the high and low input. Although the performance would have to be better for this to become a commercial product, through development, the design would have potential to work in a home setting. The big issue of attenuation and distance at which it functions is the only thing stopping the POP from being considered for further development. For this reason a second solution looked to negate this issue of malfunction over increasing distance.

AFFA - Adjustable Frequency Fire Alarm

29.0 Wireless Alarm System Prototype This system, like the previous looks at sending information as to a hallway unit alarming, to a unit setup in the bedroom. This system however, aims to mitigate the previous dis-advantages associated with the first system. Through using a wireless sending and receiving unit a system that operates over a larger distance and with more reliability has been achieved. This system also includes the varying frequency solution, which allows the user to select pre-defined frequencies to the one that best suits them and also allows for waking via a strobe light and a vibrating pad, both of which are able to be turned off and in the case of the vibrating pad, removed. Varying Frequency Output

Wireless alert Specially adapted wireless Fire Alarm

Strobe Light

Adapted fire alarm system

Vibrating Pad (2m wire) Figure 41 - Wireless alarm system

29.1 Hallway Unit The hallway unit which was designed to send information that it has detected a fire, works in much the same way as the adaption that was made to the household alarm in the 1st proof of principle prototype. However, instead of emitting a sound at 3Khz, when detecting a fire it sends a wireless signal using out which can be received by the bedroom unit.

Figure 42 - Wireless alarm Hallway unit (sending wireless alert) AFFA - Adjustable Frequency Fire Alarm

48 49

This POP uses a fire alarm circuit to output a wireless signal only, to further develop the sending unit, it would include the same adjustable frequency selection mode that the receiving unit does. This would then allow both the hallway unit and bedroom unit to be fine tuned to the frequency best suitable for the user. It was reasoned that this solution need only be realised once and the most important unit to place it on would be the receiving, bedside unit. The Schematic for the Sending Hallway Unit is included in Appendix M.

28.2 Bedside Unit The bedside unit has been developed to include a frequency control button, a strobe light and a vibrating pad. Through user research it was understood that the best way to realise this solution would be to include the vibrating pad as one that can be removed and the strobe as one that can be turned off if the user desires . Feedback on the vibrating pad showed that some people thought it to be intrusive, however its inclusion is essential to cater for an inclusive market meaning it must be detachable so each user is able to user it their own way . As this system relies totally on digital inputs and outputs, the main area for development lies in the coding stage, the consideration as to how the design functions is in the different frequencies of sound that can be selected and how those frequecies are chosen by the user (the button layout). Other considerations come in the form and development stage, when product position and interface is identified and analysed. The Schematic for the Receiving Bedside Unit is included in Appendix M.

Figure 44 : Image of Bedside unit POP (Receiving wireless alert)

AFFA - Adjustable Frequency Fire Alarm

30.0 Wireless Alarm System Programming Once again, much like the first prototype, two sets of code have been produced, one for the sending Hallway unit and one for the receiving bedside unit. Below are the flow charts that were followed when writing the coding. The different frequency outputs have been realised, as in the first prototype by post-width modulation (PWM) which allows calculation of square wave frequencies within the PIC. The coding for the Sending Hallway unit is situated in Appendix N, whilst the coding for the receiving bedside unit is located in Appendix O.

No Has byte been received?

No Has Test Button being Pressed? / Fire Detected?

Yes No

No Is Strobe light plugged in?

Yes

Is Vibrating pad plugged in?

Turn on Strobe Light

Turn on Vibrating Pad

Output sending byte Output desired frequency of sound (set by user)

Figure 45 :Flow Chart of Coding used to send Wireless alert.

Figure 46 :Flow Chart of Coding used to ReceiveWireless alert.

31.0 PCB Development As before various PCBâ&#x20AC;&#x2122;s were developed before the correct sizing and functioning ones were produced. The PCBs produced for both the wireless sending and receiving circuits are shown in Appendix P.

AFFA - Adjustable Frequency Fire Alarm

50 51

32.0 Wireless Alarm System Testing With a completed system that now functions using wireless radio waves, the new system can be tested. The main area for testing is that of the distance increase the new system offers. In the same way the previous prototype was tested, the distance the product was found to work too, was around 200m, this included functioning through a wall, which, if the bedroom door was closed at night time would give rise to a more successful solution than the previous prototype.

32.1 Testing Coding Testing of the coding function is also important. Taking note of the research paper â&#x20AC;&#x153;Waking effectiveness for alarms (audiotory, visual and tactile) for adults who are hard of hearingâ&#x20AC;? along with research into the various types of hearing loss and how frequency of sound can affect peoples hearing cabilities, the frequencies that can be chosen must be set in the coding, so that the user is able to toggle between then using a switch. Below figure 47 shows oscilloscope read-outs of the various frequencies that can be selected.

520Hz square wave output.

1500 Hz square wave output.

3kHz square wave output. Figure 47 : Oscilloscope readings

In this instance the frequencies that can be selected are 520Hz, 1500Hz and 3000Hz. Although many frequencies can be programmed, these three have been selected to prove the principle and to keep the product as simple as possible whislt maintaining the inclusivity.

AFFA - Adjustable Frequency Fire Alarm

33.0 Switch Development & User interaction With two parts to the system, how each is to be activated must be considered. Included with the wireless POP is the development of how each part of the system will be triggered.

32.1 Hallway unit Switch Development Since this unit is essentially a household alarm, with the addition of a wireless sending unit, the triggering system has been developed as a normal alarm would be. With a press button solution that recoils upon release. The button is to only be drepessed when testing the alarm, which should occur once a month, to allow maintenance of the alarm if necessaryto be undertaken. Image on left shows household alarm, the way it recoils would be included in the AFFA product, for now the solution is solved with a spring (right image).

33.2 Bedside Unit

Figure 48 :Button development for wireless POP prototype

With the bedside unit prototype, consideration had to be given to 3 areas. 1. Reset switch. 2. Vibrating pad On/Off scenario. 3. Strobe light On/Off Switch 4. How the frequency is to be changed. A reset switch was included, so that when the alarm sounds because of incoming hallway signal, if there is no fire and it was a test, the unit can be reset after it has received the signal, making sure it does not continue to go off. This inclusion, just makes sure that the transmitter and receiver are working together properly. The vibrating pad does not have a switch, instead it is considered as being either in use or not in use. If it is needed, upon being plugged in, it will function when signal is received, and if not needed it can be unplugged for storage.

AFFA - Adjustable Frequency Fire Alarm

52 53

The decision to bulid the strobe light into the unit means that unlike the vibrating pad the unit is not detachable. The strobe can be activated and de-activated by using the corresponding switch. This allows users who do not need the light or because of epilepsy cannot have the light it can simply be turned off. The frequency can be changed on the protoype, by the circular toggle on its side. By rotating the toggle the different frequencies can be selected. Careful placement of these buttons has had to be considered, the side has been selected for placement, so that the front is free for the alarm covering and the back is free, so that it is flat and can be placed on a wall. The amount of times the buttons are expected to be used is minimal. Once the user has selected the frequency they can hear the best, it is not likely they are going to touch the selection toggle again. Likewise with the strobe light, a user will either choose to have it on or off. The vibrating pad connection is likely to see the most use as when waking up, the user may chose to disconnect it and store it during the daytime, only to reconnect in the evening.

Figure 49 : Latching switch to turn alarm & strobe on/off & frequency changing dial. along with vibrating pad connector.

AFFA - Adjustable Frequency Fire Alarm

34.0 Evaluation of Wireless system prototype. With the wireless system complete evaluation can be made. Like the previous system, it has been evaluated against certain points of the PDS.

34.1 Usability The wireless prototype, unlike the frequency filtering system, has two modules that need to be installed. Each require batteries of their own. The Hallway unit requires no setup apart from plugging a battery in. The Bedroom receiving unit, has 2 buttons and is automatically on when a battery is plugged in. The two buttons operate both the strobe light and frequency selection. The frequency selection has been developed with a turning button. The sounds are changed by simply turning the dial and listening. As the end user is not concerned with the frequency is, but rather whether they can hear it, the frequency has not been printed on the design, instead the dial selection process is to be included in the information leaflet. With simplistic buttons the usability of the product is easy to setup with an information leaflet.

34.2 USP The USP of this prototype is that is contains the frequency changing system, as well as the wireless alert.

34.3 Price Point The system, because of the use of wireless chips is to be more expensive than the previous system. Although different components may be used if the product was to be commercially produced, the current prototype would cost around ÂŁ50, although it offers more features and a more stable information relay system.

34.4 Performance The performance of this prototype is consistent. The wireless radio signal has increased the range of the product to around 200m. The addition of electrical components that allow for changing the frequency has enhanced the variety of performance and allows the product to cater for a much wider market, fulfilling the inclusive design specification the project was set out to be designed too.

AFFA - Adjustable Frequency Fire Alarm

54 55

35.0 User Feedback To deduce which prototype is preferred a user group was setup up at the RNID on 15/4/10. This aimed to clarify peoples views on the systems. Working closely with the hard of hearing community has meant the feedback is of the highest quality. A questionnaire was devised to discuss the positives and negatives of the AFFA alarm whilst statements recorded as to the thoughts about each design, that can be compared and evaluated. The AFFA product considered to be the final design solution, was also looked at by RNID techical evaluators as well as Tom Fiddian a product designer at the RNID. Their thoughts on the design are included on pages 71-73, in the external evaluation section.

35.1 User feedback on prototype 1. Filtering system. Statements about the prototype that were made during the user group. “The lower sound is alot easy to hear than the normal fire alarm I have. I like the potential of the product being relatively cheap, however am unsure on its reliability”. “I am not sure on how the product would function in a household, I have a specialised alarm already, how would it work with that?” “I really like the idea of a cheaper specialsied alarm, the current systems are too expensive” “I would like to be able to change the sound myself, I am not sure if the new lower sound is the best for me”. The statements indicate inconclusive thoughts on the success of the prototype. People wanted to have more tones available as well as being uncertain on if the alarm would function with their alarm at home. The way in which this problem is solved is to have develop acoustic software to recognise fire alarm tones and beep patterns, to be able to identify all types of household alarm available. This would then push the price of the alarm up and defeat the object of having a cheap specialist fire alarm. It is for this reason that it is unlikely this solution is be the best. These comments also confirm intital thoughts on the prototype and back up why the wireless system was developed.

AFFA - Adjustable Frequency Fire Alarm

35.2 User feedback on prototype 2. Wireless system. Statements about the AFFA solution made during the user group. “I could hear the alarm well with my aids, but without, the prototype volume level is not enough for me, I am able to slightly make out the lower frequency, but cannot hear the rest at all. I think if it were at 90db, the lower sound would be perfect for me” “I like not having to have the vibrating pad or strobe on if I do not want too.” “Having the dial to change the sound means I can listen to which is best for me to hear, if my hearing were ever to deteriote further, I would not need to buy a new alarm”. “Being profoundly deaf, having the vibrating pad and strobe light is essential for me.” “Having the hallway unit would allow for increased peace of mind. Knowing that I have more time to react to a fire is good.” “For my type of hearing loss being able to change the tone is great” “I do not need the vibrating pad, it is uncomfortable to sleep with. Having the option to remove this is great as I am able to make up for its loss by chaning the sound to one which I am able to hear better.” The positive reviews show that the adjustable frequency aspect of the alarm is one that hard of hearing people really do need. Having the wireless system is a bonus as the extra time that can be gained from faster alerting is critical. There is alot more development at this point that needs to be done, for instance having a larger range of frequencies available to make sure the best for the user can be acheived as well as according to the RNID techincal evaluator having the product mains powered to ensure it falls in line with the BS standard 5446-3.

Figure 50 :Profoundly deaf end user evaluating the AFFA product. AFFA - Adjustable Frequency Fire Alarm

56 57

35.3 AFFA Prototype questionnaire Whilst conducting the user group, the 5 people involved were asked to fill out a questionnaire to clarify their thoughts on the prototype. The questionnaire is shown in Appendix Q (please refer to for full questions asked). The people surveyed aged from 41-60, with hearing loss ranging from profound to mild.

User

Question Rate the prototype from 1-5.

Average response

4.6

Which Frequency was ? best for you?

3Khz 520hz

1500hz

Figure 51 :Profoundly deaf end user evaluating the AFFA product.

Results from other questionned asked confirmed that everybody thought the option to turn the strobe light on/off was a good idea. The one anomoly was from the first user who when their aids were out could not hear the sound form the alarm. It is thought this is for two reasons, 1, the prototype db is not at 90 and the other that the user was over-estimating their hearing ability and that a vibrating pad may be the better option to wake them.

AFFA - Adjustable Frequency Fire Alarm

36.0 System Development Clarification With the end user feedback positive about both products, both can be deemed a success. However, the reviews have confirmed that the AFFA wireless system fulfils the function the best. Further analysis to ensure the AFFA solution has improved upon the current RNID solution has been undertaken. The use of the life cycle analysis tool on the new design has been completed (shown below) together with part count to see how it equates to the Dewhurst and Boothroyd analysis carried out in the research stage.

36.1 SLCA of ‘AFFA’ wireless solution. 1) Manufacture and extraction phase. Assumption of 55MJ/kg for all non-electronic parts and 2000MJ for all electronic parts. Product total weight = 0.350 Kg Weight without electronics = 0.34 Kg 0.34 x0.1 = 0.034MJ Weight of electronics = 0.250 Kg 0.01 x 2000 = 20MJ Total = 0.034 + 20 = 20.034 MJ 2) Transport Phase - Assumption of 15MJ for journey from shop to users home. (1MJ ship, 3MJ Lorry, 10MJ Van) 3) Use Phase - Use time is 24 hours a day 7 days a week 365 days a year. Energy per day = 60 seconds x 60 minutes x 24 hours = 86400 seconds 86400 x 1.2W = 103680J Over lifetime = 15 x 365 x 103680J = 567648000J = 567.648MJ over 15 years. Power station losses 3 x 568 MJ = 1704 MJ = 1.7 GJ 4) Disposal phase - Assumption 2 MJ/Kg 0.350 x 2 = 0.7 MJ Total energy comsumption over 15 years = 1735 MJ This, compared with the RNID solution coming in at 2078.49MJ over 15 years, is an improvement. The RNID fire alarm has been broken down to be more accurate, whereas the AFFA solution is assuming the manufactured product weight to be minimal, due to light PS snap fit parts.

37.1 Dewhurst & Boothroyd Analysis The part count analysis of the RNID fire alarm showed that a solution could be achieved with as little as 14 parts and the AFFA solution has aimed to do just this. The part count for the solution is thus, Front & back cover x 2 = 4 snap fit sections, 2 for each alarm. 2 PCB’s, one for hallway unit and one for bedroom. 1 Vibrating Pad 1 Strobe light 4 Screws (supplied to fit to wall) 2 Batteries.

AFFA - Adjustable Frequency Fire Alarm

58 59

37.0 RNID Brand Careful consideration has been given to the aesthetic qualities of the product. With current fire alarm systems being ones that have bland colours and little appeal, the development of an aesthetic solution for ‘AFFA’ has aimed to be bolder and easier to include into the home. Most solutions are white PS and conjure images that the particular product is a specialist one. Whilst the seriousness of the product must be maintained, ‘AFFA’ has looked to inject colour and form into the design of the new product. The RNID uses a blue colour of pantone reference 072 .and a yellow of reference yellow C, these have both used in the development of form, together with white to indicate allow the product to be identified as an alarm.

36.1 ‘AFFA’ ‘AFFA’ stands for adjustable frequency fire alarm. It is a name that have been used to not only describe the product through acronym but also be one that is easy to remember.

Figure 52 : RNID Brand Logo AFFA - Adjustable Frequency Fire Alarm

38.0 Aesthetic Development With the end user in mind, the form has been developed accordingly. Current specialised systems generally pay attention to function only, neglecting the form of the product. The AFFA Solution has looked to incorporate both the seriousness of the product, together with one that is more aesthetically pleasing to have in the home. With the solution proposed to sit in the users bedroom, the alarm must have mutual colours, be of a form which is universally accepted and be in keeping with the RNID brand. The form of the model creates a sense that the product is friendly and can easy be accepted into the home. The two blue sections denote where the products strobes lights would be positioned if AFFA were to be manufactured. A white finish has been used for the body to indicate it is a fire alarm, together with the holes for the speaker and for the smoke to enter if a fire is occurring,.

Figure 53 : AFFA development model AFFA - Adjustable Frequency Fire Alarm

60 61

Figure 54 : AFFA Final Model

39.0 Material Consideration ‘AFFA’ is to be produced using Flame retardant PS, for both the front and back sections of the design. The casing for both the main body and vibrating pad are to be injection moulded. Other important areas to consider are those of the markings the product must have. It must be in accordance with the WEEE directive, especially because of the hazardous Americium substance found within. Meaning of each indicator Indication that product can be recycled (not that it has been recycled)

Eco-labels Mobius Loop Deutches Duales

Although not applicablein the UK, is an idication representing recycling targets.

EU energy label

System for notification of energy efficency of white good products.

CE Conformité Européenne

The CE marking certifies that a product has met EU consumer safety, health or environmental Figure 55 : Eco-indicator table

The table shows the eco-indicators the product must have, both on its casing and packaging.

AFFA - Adjustable Frequency Fire Alarm

40.0 Product Placement The way the form has been designed is both with a base that the product can stand upon, should it be in the users bedroom on a sideboard and with a flat back, should the user choose to hang it in the hallway, or behind the bed. Having it on the wall also means that the vibrating pad trailing lead does not clutter the sideboard and can be looped under the users pillow from behind their bed. The image below shows the product placement within the home. The alarm needs to visible but not intrusive in a bedroom setting.

Figure 56 : AFFA solution in place on user bed-side table.

AFFA - Adjustable Frequency Fire Alarm

62 63

AFFA - Adjustable Frequency Fire Alarm

Alarm may fail if there is an electrical fire.

User is not woken by sound.

Backup battery fails.

Sound does not emit. 8

User cannot be woken by strobe.

Strobe light blows.

Battery does not stay in correctly.

Incorrect Manufacture.

Power surge may cause stobe to blow.

Incorrect Manufacture.

Constant plugging in and removing from alarm.

Weak point in plastic moulding.

together properly.

User may twist the dial too hard.

Cause

Occurance

6 Parts may have not snap fitted 5

Sound may not be produced

Alarm does not function.

User cannot change frequency.

Effect

Severity

User cannot be woken by vibrating pad.

Vibrating pad connection point becomes worn down.

Cover snaps.

Battery does not engage with alarm.

Frequency Dial fails.

Failure Mode

Quality Control : checking circuitary is correct.

User testing : test angle of insertion.

Quality control : Check mould flow rate of injection moulding machine.

Quality Control : Check parts are fitted together.

Testing : Carry out force tests on the dial.

Quality Control : Check dial is in place.

Detection Method

Detection 2

100

108

Check functionality of circuit boards

Check tolerance of input hole.

Run tests of moulding before manufacture.

Check the assembly stage of manufacture.

Design to be strong enough to mitigate human error.

336

Check the assembly stage of manufacture.

RPN 28

Recommended Action

41.0 FMEA of AFFA solution

To establish possible faults with the alarm, if it were to be manufactured an FMEA has been carried out. Looking to predict the way the product can potentially be mishandled, by the suggested target market or mis-manufactired can lead to mitigation of any possible failure.

Figure 57 : FMEA of AFFA Design solution.

42.0 Solidworks Development Using Solidworks has allowed for the finer elements of how the product will fit together to be realised. With the complex PS front cover and back cover the product has been designed to have, it was crucial for CAD realisation to be undertaken to ensure the products stability. It has also allowed for various colour schemes to be viewed before prototyping and allowed for specific dimensional and assembly drawings to be created. These are shown in Appendix R.

Figure 58 : Solidworks Cad Rendering showing AFFA with Strobe light on.

Both the sending and receiving units have been designed to fit into the same form, with indication as to which unit is which located on the back ofthe product. For prototype purposes only one model has been made to indicate the final form of each alarm.

AFFA - Adjustable Frequency Fire Alarm

64 65

43.0 User Feedback on Aesthetic model To gain adequate feedback on how the end user feels about AFFA it was taken along to the RNID, together with the final prototype models. “How the alarm would look is really nice, a big improvement on the current alarm that I have which is not so attractive.” “I like the shape, as the lights are in the top corners, but why blue? I do not want to be reminded I have a specialist alarm”. “This is a much better size, it wouldn’t take up that much room in my home.” The form development and colour scheme was overall liked by the users who viewed it. It seems as though, on one hand people do not want a product that is identifiable as ‘specialist’ whilst on the other, they do not want one that is coloured in such a way it reminds them the alarm is there. With AFFA a happy medium is delivered as the colour scheme and form reflect the users views.

AFFA - Adjustable Frequency Fire Alarm

44.0 Service Development With the market defined as people who are deaf and hard of hearing, careful consideration has to be given to the instruction leaflet layout and language using clear diagrams along with easy follow instructions. The setup of the system is not too difficult as the way in which it functions has been considered throughout. The set up here is for the prototype models, it is likely that the model that would be manufactured would be mains power supplied.

2. Hallway Unit

Bedroom Unit

1. Remove back cover. 2. Place battery in compartment. 3. Replace back cover.

4. Remove back cover. 5. Place battery in compartment. 6. Replace back cover.

4. Testing 7. Press and hold Hallway unit test button. 8. Use dial to change frequency on Bedroom unit. 9. Press switch to turn on/off strobe light. 10. Connect vibrating pad if desired. Figure 59 : Instructions of intended product setup.

AFFA - Adjustable Frequency Fire Alarm

66 67

45.0 Bill of Materials To calculate the unit price for the system, the material cost must be noted. This has been done by adding the total component cost for each section of the proposed design. The components for each unit have been totalled together, as the system would be sold as one product, even though there are two modules. Component Type

Electrical

Hallway unit

Bedroom unit

Qty 1 1 1 2 1 2 1 2 1 1 1

Mechanical

2 6 1 1 1 1 Hallway unit Bedroom unit Packaging

1 1 1 1 1 1 1 1

Item

Material

Fire Alarm Circuitary Pic Microcontroller Wireless Transmitter All Wires Pic Microcontroller BC108 Transistor Voltage Regulator Capacitors Wireless Receiver Amplification Circuit Resistors Speaker Switch DC input Jack DC output Jack Vibrating Pad Strobe Circuit Front Cover Back Cover Front Cover Back Cover Strobe Light Casing Vibrating Pad Casing Box Instruction Sheet

Total Cost (ÂŁ)

Polypropylene Polypropylene Card (150 gsm) Paper (40gsm)

0.50 2.00 10.00 0.10 2.00 0.20 0.20 0.10 12.00 1.00 0.06 0.50 0.50 0.30 0.30 0.90 1.00 0.40 0.40 0.40 0.40 0.30 0.70 0.30 0.05

Total Unit Cost Sale price (Profit of 35%)

34.61 48.45

Polystyrene Polystyrene Polystyrene Polystyrene

Figure 60 : BOM breakdown.

The Bill of Materials is based upon the prices paid for the various parts needed to complete the prototyping. Part prices for the Mechanical section, where PS and PP covers have not been produced have been presumed. It must be realised that these parts have been bought at market price. If the alarm were to be manufactured, the % markup the components have already gone through before purchase would be less. This % is expected to be around 50%, it can be assumed that base price the component parts can be halved meaning the total unit cost at point of manufacture would be ÂŁ 17.305. AFFA - Adjustable Frequency Fire Alarm 67

46.0 Route to Market ‘AFFA’ is most likely to reach the end user via 2 methods of distribution, Retail, both store and online, and through specialist suppliers & fire safety schemes.

45.1 Retail Both shopping online and in store is an outlet for which the product can be sold. The identified target market poses a problem to the product retail. With elderly people who are deaf or hard of hearing, there may be the scenario that they themselves purchase the product, there may also be the scenario whereby a family member who wants to help their relatives purchases in store. The troublesome area lies with the people who are hard of hearing but have not comes to terms with needing ‘specialist’ equipment. When looking in store at the range of alarms and seeing the various price points of different alarms, somebody who considers themselves not in need of the ‘AFFA’ product may opt to buy the cheaper alternative. (This is where development of the first filtering system prototype may prove worthy, keeping price point low). Online retail is only going to be a success for people who are looking for the right hard of hearing alarm. It may be of benefit to make a range, out of the ‘AFFA’ products. For instance, 1. Lowest price point - a stand alone hallway alarm that emits at 520Hz 2. Middle price point - A slightly more expensive alarm, that relies on sound filtering and is limited by distance. 3. Highest price point - The wireless system with varying frequency available in both the hallway and bedroom. This way, dependant upon severity of hearing loss a product can be chosen. With a stand alone adjustable frequency fire alarm, competition would be given to less expensive competitors, and in store, sales may be greater.

45.2 Specialist Suppliers It is more likely that the product is to be sold via specialist outlets. The RNID solutions magazine offers hard of hearing products and advertising through this medium is likely to bring the most product sales. Other suppliers such as Bellman, Lifetone (USA), Connevans also have specialist magazines in which AFFA could be sold through. There is also the option for potential government funding alongside the fire kills scheme. Demonstrations off ‘AFFA’ at events could lead to raising product awareness and increasing sales.

AFFA - Adjustable Frequency Fire Alarm

68 69

47.0 Return on Investment For the product to be successful in the marketplace, its profit margin must be calculated. The return on investment charts depicts the prices of key areas that the product has to go through before reaching the home. The part cost has been gained from the bill of materials chart. The assumed base price for the components has been used, as supposed to the bill of materials price, which includes a mark-up percentage. The table charts the profitability of the product in the UK market over 5 years. The figures used for the year to year sales have been estimated, with increasing sales over 5 time.

Development Costs

Cost

R&D Prototyping IP Product Testing Tooling Total

100,000 50,000 80,000 100,000 100,000

Reasoning Overheads, management, labour Visualisation, prototype moulding European Intellectual Property Testing of product attributes All tools needed for moulding

430,000

Manufacturing Part Cost Processing Cost Assembly Cost Overheads

17.30 5.25 3.50 8.65

Total Production Price

ÂŁ35.00

Profit (40% mark up is assumed as well as part cost being 17.30)

RRP

ÂŁ49.00

Recommended Retail Price

5 Year Sales UK Income from Sales (RRP x Total Sales)

Profit

50% of total manufacturing cost - material, design, volumes, process etc 15% of total manufacturing cost - Process, machinery, tooling, accuracy etc 10% of total manufacturing cost - Type, layout, time, control etc 25% of total manufacturing cost - Indirect labour, quality, dispatch etc

3,000 3,000

5,000 8,000

8,000 16,000

12,000 28,000

20,000 48,000

147,000

392,000

784,000

1,372,000

2,352,000

-283,000

-38000

354,000

942,000

1,922,000

Total 48,000

Figure 61 : Return on Investment Table.

AFFA - Adjustable Frequency Fire Alarm

48.0 Evaluation of product against PDS With the prototypes complete and analysis and end user evaluation completed, the initial PDS can be revised. Below are the points that have been revisited and updated. The PDS is now specific to that of the wireless adjustable frequency fire alarm solution. 3.

Hallway unit

Bedroom unit Wireless detection.

Various frequency output with inclusion of strobe light and vibrating pad.

6. The frequencies that the alarm can be set too are 520Hz, 1500Hz and 3000Hz square waves. 9. Product is to be mains operated with battery backup to be in accordance with BS 5446-3 Fire Detection and fire alarm devices for dwellings â&#x20AC;&#x201C; Specification for smoke alarm kits for deaf and hard of hearing people. 27. Product to sound at 90 db at distance of 3m from base unit. 34. Powered by mains 240V input with 12V battery backup that lasts for 100 hours. 35. Product is to be on 24/7. Batteries battery backup to last 100 hours. Testing regularly is recommended. 53. Total manufacturing cost has been calculated to be ÂŁ34.85 and should not be exceeded. 54. Retail price to be 49.99. 62. Combined weight of components used in Hallway unit and Bedroom used is 350g. Total weight not to exceed 350g with PS covering and product packaging.

AFFA - Adjustable Frequency Fire Alarm

70 71

49.0 External Evaluation Both Tom Fiddian, RNID product designer and Kevin Taylor RNID Technical Evaluation Manager at the RNID evaluated the AFFA wireless prototype, this is what they had to say about it. Tom Fiddian “Freddie’s approach towards the original brief is rather interesting. Instead of designing a more inclusive mainstream product, in this case a standard smoke alarm, he has developed a more inclusive assistive device. Both of the above methods would cater for the millions of people who cannot hear a standard smoke alarm; however the former method is the most conventional. By taking this original approach to the problem, he has produced something that is far more supportive to the high-risk users. As the product not only provides a low frequency audible alert but a vibrating pad and strobe it provides a more robust solution that is adaptable with the users hearing loss. For example, if a user has a hearing loss and is worried that they will not hear their alarm, they only have two options; keep their existing smoke alarm or get a specialist deaf alarm that does not have an audible alert. By creating this product he has created a pragmatic third option; it may be bought because of its low frequency alert, but as their hearing deteriorates they have the option of using the pad and strobe. As most people overestimate their hearing ability, this is a very useful function.” Kevin Taylor “As with commercially available smoke alarms for deaf and hard of hearing people, the prototype has an effective vibrating pad and Xenon strobe light. What makes this design unique is option to select different audible alarm frequencies (currently there is no commercially available smoke alarm on the UK that has this feature). One of the audible alarm frequencies that can be selected is a 520 Hz square-wave tone. Research has shown that this frequency is more effective in waking people with mild to moderate high frequency hearing loss compared conventional domestic smoke alarms generate 3000 Hz or higher. The design has been well thought out and I am sure that UK / EU manufacturers of smoke alarms for deaf and hard of hearing people would be interested to know more about it.”

AFFA - Adjustable Frequency Fire Alarm

50.0 Final Project Review The importance of being alerted in the event of a fire is one that should never be under-estimated and with hearing loss affecting over 9 million people in the UK alone (RNID, â&#x20AC;&#x2DC;10) an inclusively designed solution is vital to the security of these peoples homes. With many products available that offer specialist alerting, there are very few that are inclusively designed that look to incorporate those who are hard of hearing as. With this is mind, AFFA (Adjustable frequency fire alarm) has been designed and is ideally positioned to take advantage of this market opening. With the brief one that can be interpretted in a variety of different ways, key research had to be completed to gain feedback on end users hearing capability. With the variety of different hearing levels, the adjustable frequency fire alarm was developed and is considered to be a solution that meets the needs of a wide variety of people. By combining the adjustable frequency ability of the alarm, together with a strobe light a vibrating pad and keeping each one seperate from each other in the system, means that each user is able to customise their alarm to best suit their specific need. The final prototype combines these auditory, visual and tactile elements into both an aesthetically pleasing form one that has minimal setup requirements. AFFA has been a success and is considered by Kevin Taylor, Technical Evaluation Manager at the RNID as a â&#x20AC;&#x153;unique option to select different audible alarm frequencies (currently there is no commercially available smoke alarm on the UK that has this feature).â&#x20AC;?

AFFA - Adjustable Frequency Fire Alarm

72 73

51.0 Further Development Regardless of the complete prototypes , to take the design to market would require much more development. The project to date, although taking an in-depth look at the identification of needs and prototypes of how the system would function needs a lot more work on it. The two most important aspects for further development are those of looking at different electrical components and assessing the PCB size and how the electronics would be produced in a production line, as well as testing and evaluation on how well the product is able to wake people. With extensive research on the best way to alert people that are asleep having already been carried out by Bruck in the document â&#x20AC;&#x153;Waking effectiveness of alarmsâ&#x20AC;?, it can be said with confidence that the AFFA solution will be able to wake a sleeping person. Tests would need to be carried out to ensure that it does indeed fulfil this statement. For this testing, at least 100 people with varying different hearing capabilities and different levels of deep sleep need to be would need to be evaluated. Further development can also come in the enhancement of the system to more than one hallway unit and bedroom receiver. With wireless technology in place, the modularity of the design allows for many alarms to function from one base unit. In certain settings, such as larger houses it may be useful to have a system that has multiple modules allowing for a system to be put in place. Through the use of transceivers the AFFA could be developed so that communication can be had between many units in a household. In terms of the first system that was developed that enabled household alarms that people may already have to be heard by a specialist unit, this idea could be returned too for further development and possibly launched alongside AFFA as a cheaper alternative for people who only need two alarms in their home (people who live in a flat), thus fulfilling another market niche and allowing cheap access to specialist equipment. In all cases, further development of the casing for the alarms is needed, with electronics development, the exact sizing of the PCB could be determined and this would give rise to returning to the CAD model to produce exact dimensions for the inclusion of the electronics into the design with snap fit parts being moulded into the back section of the alarm cover. The inclusion of a test button on the Bedroom unit is also a necessity. It is too hard to test the hallway unit with one hand whilst adjusting the bedroom unit with the other. A way must be devised so that the bedroom unit frequency can be set on that unit but also tested from the Hallway unit.

AFFA - Adjustable Frequency Fire Alarm

52.0 Acknowledgements Without support from the following people this project would not have been possible : Karen Jordan - For always being a little bit mental but mostly for keeping me fed. Renee White - For always being there for me as well as offering her Audiology knowledge!. Phillip Willmore - For his amazing taste in music. Paul Barrett - For his patience with having deal with me being around all the damn time!. Richard Rakowski - For his support through the project. Joe-Simon Wood - For letting me beat him at university challenge every week. Devraj Joshi - For knowing something about everything. Tom Fiddian - For being my RNID contact!.

Thank you all!

AFFA - Adjustable Frequency Fire Alarm

74 75

53.0 References Audiology Awareness http://www.audiologyawareness.com/hearinfo_audiogramread.asp [Accessed 28th Oct ‘09] Bruck. D & Thomas.I Waking effectiveness of alarms (auditory, visual and tactile) for adults who are hard of hearing. NFPA June 2007 Available at www.nfpa.org/assets/files/PDF/Research/hardofhearing&alarms.pdf [Accessed Nov 2nd ‘09] BS 14604:2005 Smoke alarm devices. [Accessed 2nd November ‘09] BS 5446-3 Fire Detection and fire alarm devices for dwellings – Specification for smoke alarm kits for deaf and hard of hearing people. [Accessed 2nd November ‘09] Bupa Foundation http://hcd2.bupa.co.uk/fact_sheets/html/Hearing_Loss.html [Accessed 15th Nov ’09] Connevans Product selection http://www.connevans.co.uk/store/viewProduct.do?id=520151 Dangerous Decibels http://www.dangerousdecibels.org/hearingloss.cfm [Accessed Oct 27th ‘09] Deafness Research http://www.deafnessresearch.org.uk [Accessed Oct 27th ‘09] FEMA- Fire emergency management agency.Fire risks for the deaf and hard of hearing Dec ‘99 Available at http://www.usfa.dhs.gov/downloads/pdf/publications/fa-202-508.pdf [Accessed Nov 10th] Gertsakis,’01 - Design & environment : Global guide to designing greener goods. Greenleaf Publishing. Gwynne. S Optimizing fire alarm notification for high risk groups. NFPA 2007 Available at http://www.nfpa. org/assets/files/PDF/Research/Notificationsummaryreport.pdf [Accessed Nov 23rd ‘09] Hear it - Hearing loss Figures - http://www.hear-it.org/page.dsp?area=134 [Accessed Nov 10th] How stuff works http://www.howstuffworks.com/question124.htm [Accessed Oct 27th ‘09] Lifetone Store http://www.activeforever.com/p-5059-lifetone-hl-bedside-fire-alarm-and-clock.aspx [Accessed Nov 11th ‘09] Maltby M (2002) Principles of hearing aid audiology 2nd Edition London: Chapman & Hall Menieres Society http://www.menieres.org.uk/about_menieres_disease.html [Accessed Oct 17th ‘09] Pollution issues, domestic fires. http://www.pollutionissues.co.uk/domestic-fires.html [Accessed 9th Nov] RNID, Royal National Institute for the deaf http://www.rnid.org.uk/information_resources/factsheets [Accessed Oct 14th ‘09] Siemans ‘How to read a hearing banana’ - http;hearing.siemans.com/en/05-about-hearing/02-understandinghearing-impairment/01-hearing-loss/05-hot-to-tread-an-audiogram/how-to-read-an-audiogram.jsp [Accessed 17th October 2009] AFFA - Adjustable Frequency Fire Alarm

Taylor, K. Stay safe, Sleep easy. One in Seven Publication, March ’09 . Tinnitus association http://www.tinnitus.org.uk/ [Accessed Oct 17th ‘09] Treasure, J http;//blog.ted.com/2009/20.the_four_ways_soud.php [Accessed 17/3/10] UK government fire statistics http://www.communities.gov.uk/fire/researchandstatistics/firestatistics/ firestatisticsuk/ [Accessed Oct 29th ‘09] Valente, M, (2002) Hearing aids : Standards, options & limitations : Thieme Watson.S http://health.howstuffworks.com/hearing-aid3.htm [Accessed Oct 27th ‘09] Personal Correspondence Tom Fiddian - RNID designer. Crystal Rolfe – RNID audiologist RNID Annual conference - Contact made and kept with various hard of hearing potoential end users. Renee White - University of Eastern Michigan, USA, Studying Speach Pathologist.

AFFA - Adjustable Frequency Fire Alarm

76 77

54.0 Appendices Appendix A Audiograms of range of people who suffer from various different types of hearing loss. With many Thanks to Renee White of Eastern College, Michigan.

AFFA - Adjustable Frequency Fire Alarm

Audiogram showing normal hearing.

Audio gram showing mild bilateral low frequency conductive hearing loss

AFFA - Adjustable Frequency Fire Alarm

78 79

Audiogram showing moderate bilateral high frequency sensorineural hearing loss.

AFFA - Adjustable Frequency Fire Alarm

Appendix B Product Comparison Breakdown

AICO EI170RF Typical price*

BELLMAN SS102

BELLMAN B1460

CLOFIELD SILENT ALERT

FIREANGEL WI-SAFE

RNID SMOKE ALARM

SUMMIT MAINS SMOKIE

£150.57

£131.57

£199.00

£164.57

£34.00+

£99.00

£96.00

Yes

FEATURES Wireless (radio) Wired BS 5446-3:2005

Yes

Partly

Yes

Mains powered

Yes

Carbon monoxide

Yes

Test button

Yes

No. of additional detectors

Unlimited

Battery backup

Yes

Battery backup low warning

Yes

Radio link fail

Yes

Yes**

Partly

Wired link fail

Yes

Vibrating pad disconnected warning

Yes

Permanently Wired

Yes

FAIL-SAFE Fail-safe

PERFORMANCE Vibration level `(measured) Flashing Light (subjective) Installation Instructions

KEY

BEST

WORST

*Ex VAT - VAT exemption available for people with hearing loss ** When powered from optional mains adapter

AFFA - Adjustable Frequency Fire Alarm

80 81

AFFA - Adjustable Frequency Fire Alarm

Opinions

Scenario

At present although having her own opinions she is not able to understand the danger of a fire situation. She relies 100% on her parents, brother and dog, to alert her of anything changes in situation.

Ellie has no movement issues, however, should a fire occur, if asleep, she would have no chance of hearing an alarm. Visual and tactile solutions are the only way she will notice an alarm.

Ellie was born with a form of Cerebral Palsy, and has been profoundly deaf since birth. Her lack of Cochlears means she is unable to have any chance of ever being able to hear. She is fun, loving energetic and odd defying!.

Age : 11 Hearing loss - Profound, Klipper Feil Syndrome. Family Status : Lives at home with parents and 1 sibling. Hometown : Hainault Character : Friendly, curious

Opinions

Scenario

Narrative

Details

Tricia is not somebody who feels the need to have specialist equipment, she feels it labels her and is not something she wishes to have around her. Her hearing is not bad enough to need aids on a regular basis although she does have trouble with lower tones.

Tricia enjoys organising social occasions, however due to her type of hearing loss has trouble hearing any low noises. This means she is unable to hear the telephone ringing and has to have specialised aids to boost her hearing level.

Tricia has a rare form of hearing loss known as reverseski slope hearing loss. She is friendly, enjoys socialising and having fun.

Age : 62 Hearing loss - Reverse Ski-Slope Hearing loss Family Status :Lives with husband of 33 years Hometown : Windsor Character : Out-going, charismatic.

Tricia Barker

Personas

Narrative

Details

Ellie Hickford

Appendix C

AFFA - Adjustable Frequency Fire Alarm

Opinions

“Although happy with the current system I have, the vibrating pad is awkward to sleep with”.

When Pamela has her hearing aids in she is able to hear whilst at home, however, at night she takes them out as she is unable to sleep with them in. Should a fire occur, she would be reliant on a vibrating pad to wake her.

Pamela lives alone and has severe ski-slope hearing loss. This loss makes day to day activities hard to undertake. She relies on her hearing aids 24/7 and has systems already in place in her home to allow her to hear things such as the TV and the doorbell.

Age : 67 Hearing loss - Severe Ski-Slope. Family Status : Lives alone Hometown : Romford

Opinions

Scenario

Narrative

Details

“I do not currently have a hard of hearing alarm system and I feel I do not need to have one, A loud alarm will be fine for me”.

When Lance goes out he does have to wear his aids, this in social situations is sometimes awkward. At home it is accepted, and Lance is able to hear louder noises without his aids in. With his hearing being deduced across all frequencies the best solution for being alerted may be that of a really a loud alarm.

Lance has only slight hearing loss across all frequencies, this is due to an accident at birth. It does not affect him too much, however does need to wear aids.

Age : 22 Hearing loss - Hard of Hearing Family Status : Lives with parents Hometown : Hornchurch

Billy Laven

Personas

Scenario

Narrative

Details

Pamela Jordan

Appendix C

82 83

AFFA - Adjustable Frequency Fire Alarm

Opinions

Scenario

“I do not currently have a fire alarm in my bedroom. I do feel the need to have a system which can detect a fire and alert me in my room”

Karen, when sleeping on her right ear, losses some of her ability to hear. With her mobility not what it used to be, should a fire occur she may not have enough time to react.

Karen has only mild hearing loss in her left ear. The reason for this is thought be because of a recent stroke. Her mobility is somewhat lessened, however her hearing for the most part is ok.

Age : 48 Hearing loss - Stroke Victim, Mild hearing loss in left ear Family Status : Lives withhusband of 17 years David Hometown : Upminster

Opinions

Scenario

Narrative

Details

“I am scared for Rosies future, I am thinking of purchasing equipment to aid Rosie the best we can”.

At present, Rosie only being 2 means Tom looks out for her. Tom is worried that should a fire in the home happen, when Rosie is older how she will be alerted and directed to safety. He is thinking about setting the house up with specialist equipment so that his family get used to it and Rosie can grow up with the best possibilities.

Tom is a caring father who is very concerned for his daughter, Rosie, who was born with severe hearing loss. Much like Ellie, this is a rare situation to be in. With Rosie so young he is worried about how she will learn, interact and grow up to be able to manage her everyday life.

Age : 31 Hearing loss - None, Daughter Rosie has severe hearing loss from birth. Family Status : Lives with wife Dawn and two children. Hometown : Dagenham

Tom Davis

Personas

Narrative

Details

Karen Johnson

Appendix C

Appendix D Dewhurst and Boothroyd Analysis for current RNID Fire Alarm System

Component

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32

Main top w/blue button PP Main bottom PP Clear outer section PP Power junction Casing bottom PP Power junction Casing insert PP Power junction Casing top PP Battery cover PP PP RNID smoke alarm inner section PP Blue pull out instruction section PP Blue Side Button Two rubber feet Rubber All screws Steel Battery PP Vibrating Pad top & bottom Vibrating Pad electronics w/wire (2m) TPV Copper Wire between base & fire alarm (10m)TPV Copper Main PCB Plug w/wire (1m) TPV Copper Wire between base & junction (1m) TPV Copper Fire alarm top PS Fire alarm bottom PS Card Instruction leaflet Spring Steel Alarm plastic amplifier PP PP Black inner alarm casing Fire alarm PCB Box & Inner slip case Card Junction PCB Total Total w/out electronincs

AFFA - Adjustable Frequency Fire Alarm

Weight (Kg) Qu 1 Qu 2 Qu 3 Qty

N N

1 1 1 1 1 1 1 1 1 1 4 11 1 2 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 42

Possible Qty

1 1 0 0 0 0 1 0 0 0 0 0 0 0 1 1 0 0 1 0 1 0 0 1 1 0 0 1 1 1 1 0 14

Reasoning Keep - Alarm needs cover. Keep - Alarm needs base. Discard - Not needed. Discard - Not needed. Discard - Not needed. Discard - Not needed. Keep - Access to battery. Discard - Not needed. Discard - Not needed. Discard - Not needed. Discard - Not needed. Discard - Not needed. Discard - Use 2 x9v Keep - Protection of electronics Keep - link to base unit Keep - link to base unit Discard - Can be wireless Discard - Can be wireless Keep - Needed for function Discard - Use Batteries Discard - Use Batteries Discard - Parts can plug into base. Discard - Strobe can plug into base

Keep - Protection of electronics Keep - Protection of electronics Discard - Print on box Discard - Not needed Keep - Needed to boost sound Keep - Protection of electronics Keep - Needed for function Keep - Protection of product Discard - Integrated into base.

Saving New Possible Weight

Saving (kg)

0 0 0.0280 0.0225 0.0030 0.0210 0 0.0265 0.0300 0.0015 0.0010 0.0115 0.3580 0 0 0 0.117 0.039 0 0.276 0.089 0.0735 0.0245 0 0 0.0045 0.0010 0 0 0 0 0.0080 1.0516 0.723

84 85

Keep system the same. focus on human factors and aesthetics to make specialist type of system more accepted into households.

Alarm that has a screen which changes colour to alert user of fire.

Alarm that has no sound only visual and vibrating alert.

Alarm that emits at 3 different frequencies. Has a strobe and lights the way for path out of room. (Light is a character for hard of hearing childrens room?)

Alarm that emits at 520Hz and has a strobe light

Alarm that emits at 3 different frequencies.

AFFA - Adjustable Frequency Fire Alarm

Simple fire alarm that emits at 520Hz only.

Focus in on making a less intrusive vibrating pad? flat like that of an electric blanket, that is more comfortable to sleep with.

Alarm that sounds and via wire tells a bedside unit. Multiple frequencies.

Alarm for bedroom that emits at 520Hz and has inbuilt alarm clock

Alarm which detects fire and outputs more potent smell. One that can be smelt over flames?

System with various filters, that is able to listen for various frequency of alarm. Meaning multiple alarms can interact regardless of sound.

Filtering system. A Hallway alarm that when sounds is detected in the bedroom and sounds a different frequency alert.

Inclusion of Strobe light and Vibrating pad.

Bedside system Hearing aids can be placed upon at night-time (docked). Alarm can hear incoming sound, hearing aid recognises the sound the user can hear best when they do not have them in and emits at that specific frequency.

Wireless system. Relay of fire alert wireless to bedroom. Wide range of frequencies available for selection. Strobe and vibrating pad included.

Appendix E - GIT Chart - Summary of ideas ranging from 1, least complex to 5, most complex.

Appendix F - SWOT analysis of 4 best concepts from GIT Chart and User Feedback. 1 - Filtering Concept. Sound in bedroom is heard by using a filter. Strengths

Opportunites

• • • • • •

•

Low BOM cost Allows for multiple alarm setup System can be integrated with home alarms. Does not identify itself as a “Specialist product” Minimal installation procedure Able to run off of batteries.

• • •

To penetrate low cost hard of hearing solutions market. Possible licensing to people who may wish to take on solution because of its simplistic nature. Inclusive product nature. Easy to distribute through government fire safety schemes.

Weaknesses

Threats

•

• •

•

Use of analog detection may get interferred with noises that naturally occur. Analog detection may not be sensitive to hear alarm in Hallway sounding.

Simplistic solution is easy replocated. If product fails, manufacturer may be held liable.

2- Wireless system, whereby sound is relayed to bedroom through radio signal. Strengths

Opportunites

• • •

Easy integration into home. Allows multiple frequency outputs. Allows for use of Strobe light and viibrating pad.

•

• • •

No mains means no failure in an electrical fire. Wireless allows fast accurate relay of information. Allwos for different frequency outputs at both sending and receiving unit. Allows for multiple units to interact.

•

Weaknesses • •

• •

Threats

Uncertain if it can be a battery powered as • strobe and vibrating pad draw alot of current. • High BOM

AFFA - Adjustable Frequency Fire Alarm

Allow for simplistic solution when compared to other specialist fire alarms. Easy to setup Easy to change frequencies and allow user to customise.

Simplistic solution is easy replocated. If product fails, manufacturer may be held liable.

86 87

3 - Bedside device which hearing aids can be docked upon, and listens for alarm sounding while you sleep. Hearing aid knows which frequencies to boost when user is awake, so it will know which ones it does not need to boost when user is asleep. Thus can listen and tell system to output at frequency it knows user is able to hear.

Strengths • • •

Opportunities

Highly accurate frequency output that is unique • to each users hearing capability. User is able to sleep witout hearing aid, in • confidence. Wireless relay would allow for fast information • transfer.

Weaknesses

Great oppurtunity to create an inclusively designed project. Licensing to larger companies who caould take on idea of project. Change the way hard of hearing people are able to interact with products.

Threats

• • •

• Would probably have to be mains powered. May be confusing to setup. Would require electronics skill I do not possess! •

• •

High BOM. High Retail price.

•

Hard of hearing users fails to understand its benefits. High price, means little likelyhood of market penetration. If product fails, manufacturer may be held liable.

4 - Childs alarm that is characterised and can offer alert as well as integration into bedroom. Strengths

Opportunities

• • •

Able to be integrated into child bedroom. Allows child to grow up with sense of safety. Reassurance to parents that child is safe.

• •

•

Teaches child about fire safety.

Highlight fire safety to children. Give parents child safety reassurance.

Weaknesses

Threats

•

• •

A fire alarm is a serious product, characterising it reduces sense of danger towards fire. The suggested light, could light the way directly into the fire!. Difficult to keep a characterised object serious.

AFFA - Adjustable Frequency Fire Alarm

If product fails, manufacturer may be held liable. If child does not udnerstand what it is to be used for.

Appendix G - Sketch Ideation

AFFA - Adjustable Frequency Fire Alarm

88 89

Appendix H - RNID Fire Alarm system concept generation questionnaire. The following questionnaire aims to evaluate concepts for a new RNID fire alarm system that have been generated. All questions are optional and your feedback on the ideas are much appreciated.

1. Age 18-30

31-40

41-50

51-60

61-70

70+

2 . Type of Hearing loss ........................................................................................ 3. Concept 1 An alarm system that sits by your bedside and alerts you of a fire with a sound of your choice. The different sounds are beeping noises that can be set to be high pitched or low pitched depending upon what you are able to hear the clearest.

Not interesting Not very at all interesting

3 Neutral

Very Somewhat interesting Interesting

Additional feedback................................................................................................................................................................................................................. .................................................................................................................................................................................................................................................................. ...................................................................................................................................................................................................................................................................

4 . Concept 2 An alarm system that you sit your hearing aids on when you go to bed and it sounds at the noise that you are best able to hear. The hearing aids allow the system to understand which sound is best for you and automatically tune itself to your capability.

Not interesting Not very at all interesting

3 Neutral

Very Somewhat interesting Interesting

5. Concept 3 A bedroom alarm for your child that has a vibrating pad alert as well as a bright light to illuminate way to safety.

Not interesting Not very at all interesting

3 Neutral

Very Somewhat interesting Interesting

Appendix I Schematic for band-pass filtering system 200 Ohms

0v 12v 1k

2k2

5k1

10k

200 Ohms

1k .1mf

Voltage invertor

Diode

5k1

op-amp

1k op-amp

10k

Voltage reg 10mf .1mf 100mf 100mf

op-amp

MIC 100k

.1mf

10k 10k

100k

10mf

47k Comparator

1k POT 3k

PIC 16F628A

1k LED

1k 270 ohms

Speaker

Schematic for Alterations made to fire alarm system Amplifier +12v

+ Input from fire alarm

+12v

Voltage Regulator 1k 100mF PIC 16F628A

0.1mF

Alert input from fire alarm

10k

LED

Amplifier iutput 0v

- Input from fire alarm Amplifier ground

AFFA - Adjustable Frequency Fire Alarm

90 91

Appendix J - Coding for alterations to household alarm ;This is a test program for the 16f628 daughter boards. ;Run the program and all the LEDs (bar A5) should flash. ;Any LEDs not flashing may indicate a fault with that particular port bit. LIST P=16F628A INCLUDE P16F628A.INC __CONFIG _CP_OFF&_LVP_OFF&_BODEN_OFF&_MCLRE_OFF&_PWRTE_ON&_WDT_OFF&_INTRC_OSC_NOCLKOUT COUNT1 EQU COUNT2 EQU COUNT3 EQU

0x20 0x21 0x22

ORG

0x00

goto

START

;reset vector

REPEAT

clrf call movlw subwf btfss goto bsf bcf bcf

TMR0 DELAY .10 TMR0,W STATUS,0 REP STATUS,5 TRISB,3 STATUS,5

movlw movwf movlw movwf

.40 CCPR1L b’00000101’ T2CON

bsf

PORTB,0

goto

REPEAT

REP

bsf bsf bcf bcf goto

STATUS,5 TRISB,3 STATUS,5 PORTB,0 REPEAT

END

AFFA - Adjustable Frequency Fire Alarm

; duty cyle percentage ; enable timer2 no pre or post scaler

92 93

Appendix K - Coding for receiving alarm sound pic ;This is a test program for the 16f628 daughter boards. ;Run the program and all the LEDs (bar A5) should flash. ;Any LEDs not flashing may indicate a fault with that particular port bit. LIST P=16F628A INCLUDE P16F628A.INC __CONFIG _CP_OFF&_LVP_OFF&_BODEN_OFF&_MCLRE_OFF&_PWRTE_ON&_WDT_OFF&_INTRC_OSC_NOCLKOUT COUNT1 EQU COUNT2 EQU COUNT3 EQU

0x20 0x21 0x22

ORG

0x00

goto

START

;reset vector

;------------------------------------------------------------------------------INITIALISE movlw 0x07 ;PORTA comparator mode off movwf CMCON ;normal digital I/O bsf STATUS,RP0 movlw B’00110000’ ;A5 is input only movwf TRISA ;set rest of PORTA as outputs movlw b’00000000’ movwf TRISB ;set PORTB as outputs movlw .200 ; period is (PR2 + 1) * prescale * 1us @4MHz movwf PR2 movlw b’00100111’ movwf OPTION_REG bcf STATUS,RP0 movlw b’11111111’ movwf PORTB ;PORTB LEDs on movlw b’11001111’ ;A5 is input only, A4 open drain output movwf PORTA ;PORTA LEDs on movlw b’00001100’ movwf CCP1CON ; TMR2 PWM mode, duty cycle 2 LSB’s 0 return ;------------------------------------------------------------------------------DELAY ;approx 0.6 seconds ( approx 3 x 256 x 256 x 3us) movlw .20 movwf COUNT3 ;takes value stated in “movlw” and uses it as delay. clrf COUNT2 ;timer sequence which decrements from 255 to 0 clrf COUNT1 ;timer sequence which decrements from 255 to 254 and ;and then goes back to count 2 decrements again and ;returns to count 1, which is in decremented from ;254 to 253....etc. It uses nested loops. ;To output a delay of around 1 second a value of .3 is ;placed in movlw. This gives a value of around 1 second ;as 255x255x3x3 in milliseconds is equal to around 1s. ;has to times by 3 because the 1st loop takes 2ms and ;the 2nd 1ms meaning decrementation is 3ms more. ;The reason it starts at 255 is because a PIC has an ;8 Bit Register and if all registers are set to a value ;1 this gives 255. 1111 1111 = 255 in binary. AFFA - Adjustable Frequency Fire Alarm

DEL1

decfsz goto decfsz goto decfsz goto return

COUNT1,F DEL1 COUNT2,F DEL1 COUNT3,F DEL1

;------------------------------------------------------------------------------START call INITIALISE REPEAT

btfsc goto clrf call movlw subwf btfss goto bsf bcf bcf

porta,4 $-1 TMR0 ;Clear timer 0 DELAY ;Call delay function .15 TMR0,W ;If count is greater than 10 move 0 to W STATUS,0 REP STATUS,5 ;Set output (turn on sound) TRISB,3 ;Clear output to wait for sound. STATUS,5 ;Clear output to wait for sound.

movlw movwf movlw movwf

.100 CCPR1L b’00000101’ T2CON

; ;

bsf ;call movlw movwf call

PORTB,0 DELAY .1 CCPR1L DELAY

goto

REPEAT

REP

bsf bsf bcf bcf goto

STATUS,5 TRISB,3 STATUS,5 PORTB,0 REPEAT

END

AFFA - Adjustable Frequency Fire Alarm

;duty cyle percentage ;sets mark to space ratio ; enable timer2 no pre or post scaler

; duty cyle percentage

;stages to clear all ports, goes back to repeat

94 95

Appendix L PCB Layout of Alterations made to household alarm.

Filtering system PCB Layout.

AFFA - Adjustable Frequency Fire Alarm

Appendix M Schematic for Alarm sending unit (wireless tramsitter)

+12v 12v Fire alarm input Voltage Regulator

PIC 16F628A

100mF

0.1mF Transmitter

BC108

1k 1k

Switch

10k 10k

Vib Switch Vib Pad PIC 16F628A Voltage Regulator 100mF

BC108

8 pins for switch

Amp Input

+12v

Schematic for alarm receiving unit (wireless receiver)

Amp Ground

Receiver

0.1mF

AFFA - Adjustable Frequency Fire Alarm

96 97

Appendix N - Coding for Sending information wirelessly (Hallway Unit). ;**************************************************************************; ; RS232_H1 - V1.00 RGT : OCT 2008 ; ; DEMO CODE USING PIC HARDWARE USART TO SEND AND RECEIVE SERIAL DATA ; ; 9,600 BAUDRATE, 8 DATA BITS, 1 STOP BIT, NO PARITY OR FLOW CONTROL. ; ; DESIGNED/TESTED AT 4MHZ OSC ; ; ; ; ADVANTAGES OF HARDWARE ; ; TRUE FULL DUPLEX, USE OF INTERRUPTS WOULD HELP ; ; LESS CODE REQUIRED ; ; POTENTIALLY HIGHER BAUDRATES, DEPENDING ON OSCILLATOR SPEED ; ; DISADVANTAGES ; ; DEDICATED INPUT/OUTPUT PINS ; ; LIMITED TO 1 SERIAL PORT ; ;**************************************************************************;

LIST P=16F628A INCLUDE P16F628A.INC

; __CONFIG NOCLKOUT

_CP_OFF&_LVP_OFF&_BODEN_OFF&_MCLRE_OFF&_PWRTE_ON&_WDT_OFF&_INTRC_OSC_

; PWRTE_ON TO ENABLE POWER ON STARTUP TIMER/DELAY (72MS) TO ENABLE MAX232 GENERATED +/-10V TO STABILISE COUNT1 EQU 0X20 COUNT2 EQU 0X21 COUNT3 EQU 0X22 ;----------------------------------------------------------------------------------------------- ORG 0X00 ;RESET VECTOR GOTO START -----------------------------------------------------------------------------------------------; TRANSMIT LOOKUP TABLE, STRINGS TO BE SENT FROM PIC ;-----------------------------------------------------------------------------------------------INITIALISE MOVLW 0X07 MOVWF CMCON BSF STATUS,RP0 ; SELECT BANK 1 MOVLW B’00000110’ ;

MOVWF TRISB ; CONFIG PORTB AS OUTPUTS, B1 & B2 HAVE TO BE SET FOR RS232 COMMS MOVLW B’00100100’ MOVWF TXSTA ; SETUP 8 BIT SERIAL TRANSMISSION, HIGH BAUD RATE MOVLW .12 MOVWF SPBRG ; SET BAUDRATE 9,600 MOVLW B’00100000’ MOVWF OPTION_REG BCF STATUS,RP0 ; SELECT BANK 0 MOVLW B’10010000’ MOVWF RCSTA ; ENABLE SERIAL PORT, AND CONTINUOUS RECEPTION RETURN ;-----------------------------------------------------------------------------------------------SEND_RS232H_BYTE ; SEND THE BYTE IN W VIA HARDWARE SERIAL PORT ; EITHER CHECK THE BUFFER IS EMPTY BEFORE SENDING OR CHECK FOR END OF TRANSMISSION. ; CHECKING FOR EMPTY IS POSSIBLY MORE EFFICIENT BUT CAN BE A PROBLEM IF EMULATING, ; STEP OVER THE SUBROUTINE AND THE BYTE IS ONLY PARTIALLY SENT. AFFA - Adjustable Frequency Fire Alarm

; CHECK BUFFER EMPTY BEFORE SENDING ; BTFSS PIR1,TXIF ; CHECK IF TRANSMIT BUFFER EMPTY ; GOTO $-1 ; GO BACK AND RECHECK ; BCF RCSTA,4 ; NOP ; NOP ; BSF RCSTA,4 ; NOP MOVF RCREG NOP MOVWF TXREG ; MOVE W INTO TRANSMIT REGISTER WHICH STARTS TRANSMISSION ; CHECKING FOR END OF BYTE TRANSMISSION BSF STATUS,RP0 ; BANK 1 BTFSS TXSTA,TRMT ; CHECK FOR END OF BYTE TRANSMISSION GOTO $-1 ; STILL TRANSMITTING GO BACK AND RE CHECK BCF STATUS,RP0 ; FINISHED TRANSMISSION, GO BACK TO BANK 0

RETURN

;-----------------------------------------------------------------------------------------------START ;START OF MAIN CODE

REPEAT ; REP

CALL

DEL1

GOTO REP CLRF TMR0 CALL DELAY MOVLW .10 SUBWF TMR0,W BTFSS STATUS,0 GOTO REP MOVLW 0X33 CALL SEND_RS232H_BYTE CALL DELAY GOTO REPEAT MOVLW 0X31 CALL SEND_RS232H_BYTE CALL DELAY GOTO REPEAT

DELAY

INITIALISE

; INITIALISE INPUTS/OUTPUTS AND SERIAL PORT

; ECHO BYTE VIA RS232 HARDWARE PORT

;APPROX 0.6 SECONDS ( APPROX 3 X 256 X 256 X 3US)

MOVLW .3 MOVWF COUNT3 CLRF COUNT2 CLRF COUNT1 DECFSZ COUNT1,F

GOTO DECFSZ GOTO DECFSZ GOTO RETURN

END

DEL1 COUNT2,F DEL1 COUNT3,F DEL1

AFFA - Adjustable Frequency Fire Alarm

98 99

Appendix O - Coding for Wireless Receiving (Bedroom Unit) ;**************************************************************************; ; RS232_H1 - V1.00 RGT : OCT 2008 ; ; DEMO CODE USING PIC HARDWARE USART TO SEND AND RECEIVE SERIAL DATA ; ; 9,600 BAUDRATE, 8 DATA BITS, 1 STOP BIT, NO PARITY OR FLOW CONTROL. ; ; DESIGNED/TESTED AT 4MHZ OSC ; ; ; ; ADVANTAGES OF HARDWARE ; ; TRUE FULL DUPLEX, USE OF INTERRUPTS WOULD HELP ; ; LESS CODE REQUIRED ; ; POTENTIALLY HIGHER BAUDRATES, DEPENDING ON OSCILLATOR SPEED ; ; DISADVANTAGES ; ; DEDICATED INPUT/OUTPUT PINS ; ; LIMITED TO 1 SERIAL PORT ; ;**************************************************************************;

LIST P=16F628A INCLUDE P16F628A.INC

__CONFIG NOCLKOUT COUNT1 EQU 0X20 COUNT2 EQU 0X21 COUNT3 EQU 0X22

_CP_OFF&_LVP_OFF&_BODEN_OFF&_MCLRE_OFF&_PWRTE_ON&_WDT_OFF&_INTRC_OSC_

; PWRTE_ON TO ENABLE POWER ON STARTUP TIMER/DELAY (72MS) TO ENABLE MAX232 GENERATED +/-10V TO STABILISE ;-----------------------------------------------------------------------------------------------

ORG

GOTO START

LOOK_UP ADDWF GOTO GOTO GOTO

0X00

;RESET VECTOR

PCL NOP ONE TWO THREE

;-----------------------------------------------------------------------------------------------; TRANSMIT LOOKUP TABLE, STRINGS TO BE SENT FROM PIC ;-----------------------------------------------------------------------------------------------INITIALISE MOVLW 0X07 MOVWF CMCON BSF STATUS,RP0 ; SELECT BANK 1 MOVLW B’00000110’ ; MOVWF TRISB ; CONFIG PORTB AS OUTPUTS, B1 & B2 HAVE TO BE SET FOR RS232 COMMS ; MOVLW .79 ; PERIOD IS (PR2 + 1) * PRESCALE * 1US @4MHZ ; MOVWF PR2

MOVLW B’00100100’ MOVWF TXSTA MOVLW .12

AFFA - Adjustable Frequency Fire Alarm

; SETUP 8 BIT SERIAL TRANSMISSION, HIGH BAUD RATE

MOVWF SPBRG BCF STATUS,RP0 MOVLW B’00001100’ MOVWF CCP1CON

MOVLW B’10010000’ MOVWF RCSTA RETURN

; SET BAUDRATE 9,600 ; SELECT BANK 0 ; TMR2 PWM MODE, DUTY CYCLE 2 LSB’S 0 ; ENABLE SERIAL PORT, AND CONTINUOUS RECEPTION

;-----------------------------------------------------------------------------------------------SEND_RS232H_BYTE ; SEND THE BYTE IN W VIA HARDWARE SERIAL PORT ; EITHER CHECK THE BUFFER IS EMPTY BEFORE SENDING OR CHECK FOR END OF TRANSMISSION. ; CHECKING FOR EMPTY IS POSSIBLY MORE EFFICIENT BUT CAN BE A PROBLEM IF EMULATING, ; STEP OVER THE SUBROUTINE AND THE BYTE IS ONLY PARTIALLY SENT. ; CHECK BUFFER EMPTY BEFORE SENDING ; BTFSS PIR1,TXIF ; CHECK IF TRANSMIT BUFFER EMPTY ; GOTO $-1 ; GO BACK AND RECHECK

MOVWF TXREG

; MOVE W INTO TRANSMIT REGISTER WHICH STARTS TRANSMISSION

; CHECKING FOR END OF BYTE TRANSMISSION BSF STATUS,RP0 ; BANK 1 BTFSS TXSTA,TRMT ; CHECK FOR END OF BYTE TRANSMISSION GOTO $-1 ; STILL TRANSMITTING GO BACK AND RE CHECK BCF STATUS,RP0 ; FINISHED TRANSMISSION, GO BACK TO BANK 0

RETURN

;-----------------------------------------------------------------------------------------------;-----------------------------------------------------------------------------------------------REC_RS232H_BYTE ; RECEIVE A SERIAL BYTE, BYTE RETURNED IN RCREG AND W BTFSS PIR1,RCIF ; CHECK IF RECEIVED SERIAL BYTE GOTO $-1 ; NO DATA GO BACK AND RECHECK MOVF RCREG,W ; RETURN WITH RECEIVED BYTE IN W RETURN ;-----------------------------------------------------------------------------------------------START ;START OF MAIN CODE CALL INITIALISE ; INITIALISE INPUTS/OUTPUTS AND SERIAL PORT REPEAT MOVLW 0X0F ANDWF PORTA,W CALL LOOK_UP

CALL SUBLW BTFSS GOTO BSF BCF BCF

REC_RS232H_BYTE 0X33 STATUS,2 OFF STATUS,5 TRISB,3 STATUS,5

; ;

MOVLW .40 MOVWF CCPR1L

AFFA - Adjustable Frequency Fire Alarm

; RECEIVE BYTE VIA RS232 HARDWARE PORT

; DUTY CYLE PERCENTAGE

100 101

MOVLW B’00000101’ MOVWF T2CON CALL DELAY BSF BSF

GOTO REPEAT

OFF

BSF BSF BCF BCF BCF

; ENABLE TIMER2 NO PRE OR POST SCALER

PORTB,4 PORTB,5

STATUS,5 TRISB,3 STATUS,5 PORTB,4 PORTB,5

GOTO REPEAT DELAY ; ; DEL1 ; ; ONE

MOVLW .10 MOVWF COUNT3 CLRF COUNT2 CLRF COUNT1 DECFSZ GOTO DECFSZ GOTO DECFSZ GOTO RETURN

;APPROX 0.6 SECONDS ( APPROX 3 X 256 X 256 X 3US)

COUNT1,F DEL1 COUNT2,F DEL1 COUNT3,F DEL1

BSF STATUS,5 MOVLW .80 MOVWF PR2 BCF STATUS,5 MOVLW .40 MOVWF CCPR1L RETURN

TWO

BSF STATUS,5 MOVLW .100 MOVWF PR2 BCF STATUS,5 MOVLW .50 MOVWF CCPR1L RETURN

THREE

BSF STATUS,5 MOVLW .200 MOVWF PR2 BCF STATUS,5 MOVLW .100 MOVWF CCPR1L RETURN

END

AFFA - Adjustable Frequency Fire Alarm

101

Appendix P - PCB of Wireless Hallway unit (sending)

PCB of Wireless Hallway unit (Receiving)

AFFA - Adjustable Frequency Fire Alarm

102 103

Appendix Q RNID Fire Alarm system prototype questionnaire. (AFFA - Freddie Jordan) The following questionnaire aims to evaluate the AFFA concept for a new RNID fire alarm system. All questions are optional and your feedback on the ideas are much appreciated.

1. Age 18-30

31-40

41-50

51-60

61-70

70+

2 . Type of Hearing loss ........................................................................................ 3. How did you find the AFFA (Adjustable frequency fire alarm) solution? 1 2 5 3 4 Not interesting Not very at all interesting

Neutral

Very Somewhat interesting Interesting

4 . Which frequency was best for you to hear? Please Circle 520Hz

1500Hz

3000Hz

5. Did you find having the option of turning the strobe on and off useful? Yes No ........................................................................................................................................................................................................................................................................... 6. Did you find the option to have the vibrating pad removable useful? ...........................................................................................................................................................................................................................................................................

7. How do you feel about the idea of having a wall mounted bedside unit? ........................................................................................................................................................................................................................................................................... ............................................................................................................................................................................................................................................................................

8. If AFFA were to go on sale would you consider purchasing the product? ...........................................................................................................................................................................................................................................................................

Any Additional comments are welcomed. ........................................................................................................................................................................................................................................................................... ............................................................................................................................................................................................................................................................................ ........................................................................................................................................................................................................................................................................... ............................................................................................................................................................................................................................................................................ ........................................................................................................................................................................................................................................................................... ............................................................................................................................................................................................................................................................................ ........................................................................................................................................................................................................................................................................... ............................................................................................................................................................................................................................................................................ AFFA - Adjustable Frequency Fire Alarm 103

AFFA - Adjustable Frequency Fire Alarm

104 105

1 1 1 1 1 1

Quantity

Component 4 & 6, Snap Fit Component 3 & 4, Snap Fit Component 1 & 2, Snap Fit Component 1 &, 4 Snap Fit

Drawing does not show parts for strobe lighting or Vibrating pad. Seperate PCBs and outputs are required.

NOT TO SCALE

Notes

1. Front Cover PS 2. Speaker 3. Main Alarm PCB 4. Back Cover 5. Dial (to vary frequency) 6. Battery Cover PS

Components

AFFA Assembly Drawing

AFFA - Adjustable Frequency Fire Alarm

450

105

120

130

O 50 O5

1 1

Quantity

Drawing Number Checked 01

Date 11/04/09

All Dimensions in mm

Drawing does not show parts for strobe lighting or Vibrating pad. Seperate PCBs and outputs are required. Inner sections not shown.

SCALE 1:1

Notes

1. Front Cover PS 2. Back Cover

Components

AFFA Assembly Drawing

Drawn Freddie Jordan