Sian Vygus Development - DUO by Svygus

Si창n Vygus The Use of Tablet Devices in Further & Higher Education Development Portfolio

CONTENTS Introduction

2. Circuitry

Product Refinement

1. Concerns

3. Programming

1. Goals

131

2. Concept

4. Modelling

2. Materials

133

3. Parts

5. Reverse Engineering

3. Parts

135

4. Planning

4. DFM

137

5. DFMA

141

Human Factors Specification

1. Goals

6. Costing

143

7. Technical Drawings

145

8. FMEA

147

1. Performance

2. Task Analysis

2. Manufacture

3. Ergonomics & User Testing 72

3. Operation

3.1. Previous User Testing

4. Acceptance

3.2. Initial User Testing

5. Disposal

3.3. Mechanism User Testing

3.4. Form User Testing

3.5. Interface User Testing

Mechanism 1. Goals

2. Modelling

4.1. Product Casing Aims

3. FEA

4.2. Casing Concepts

4. Materials

4.3. Interface Aims

103

5. Connectivity

4.4. Interface Build

113

4.5. Final Interface

125

5. Final Product

129

Electronics 1. Goals

4. Desirability

Review & Validation

149

Index

163

Supporting files; such as CAD, full scale technical drawings and testing videos can be viewed at sianvygus.com

SETTING THE SCENE

INTRODUCTION The product is made up of two screens that are joined together by a hinges, This hinge allows the user to set up the screens in a variety of ways. The interface of the product alters dependent on the set up and the users preferences. The main electronics/PCB within the device will be sourced, in line with the specification points, and then altered to enable the stated functions.

Each screen will be enclosed in a hard plastic case (which the hinge is built into), and then covered with an interchangeable protective bumper, which will be available in a variety of designs. This review identifies the areaâ&#x20AC;&#x2122;s that are of high concern and need further development in order for the product to function as intended.

CONCERNS

THE HINGE

THE INTERFACE & ELECTRONICS

THE BUMPER

How can the hinge be made user friendly?

How will the device recognise what set up it is in?

Does the bumper interfer with the other features of the tablet?

Is the hinge strong enough to withstand the intended use?

What operating system will be use? Will this be altered to better suit the product?

What design options are there? How many different styles should there be?

How can the interface be made user friendly?

How can the hinge be prototyped?

What material should be used and to what tolerence?

How can the interface be prototyped?

Is it possible to pass the data and power through the hinge?

How can the bumper be prototyped?

CONCEPT Soft, customisable, and protective back plates that slip onto the main casing

device closes like a book ensuring that the screens are protected when not in use

dual screens that interact with one another to create a range of set ups (see list in top right)

Micro USB CharGING Port

the user has the following set ups to choose from; - open and apart, like a book - Open and pushed together to create one large screen - one screen half behind another (see below) - One screen fully behind the other, like a standard tablet

hinge mechanism allows the user to alter the set up of the device

volume & display change buttons

Available in a range of colours (both boxed with the device and on their own)

simple & intuitive interface that allows the user to; set their preferences, change the display, & share work with other students in an effective way

3. PARTS

As there is a tight deadline for the development of this project it was important to create a thorough project plan. Before any work was started a basic task list was created listing each area for development/work, each of these tasks were then split up into multiple smaller and more manageable tasks. From this task list a Program Evaluation Review Technique Chart (PERT) was created. Through creating a PERT chart a good understanding, and visual guide, into what tasks were dependent to each other and where tasks could run parallel to one another was gained. Initially the PERT chart was created on paper; therefore, in order to ensure that it could be efficiently referred to and edited, a colour coded digital version was created. A copy of the final PERT chart can be viewed on the next page. Although a PERT chart is good for understanding how tasks influence one another, due to it not having clear dates marked on it, it is not the most effective method for quick reference. Therefore, using the PERT chart to understand the order in which the tasks should be carried out, a digital Gantt chart was created; this day-byday plan is fully editable and displayed in a chronological order for easy reference. A copy of the Gantt chart can be view in the following pages. 5

PLANNING

The outer casing of the product is made up of two parts (see illustrations), which will both be reviewed and development. The first of these two parts (top illustration) is the main casing, this main casing is likely to me made out of a thermoplastic, such as ABS or PC, and will house; all ports/buttons, the electronic components, and the hinge mechanism. It is likely that there will be two variations of this main casing (one for each screen) in order to accommodate the hinge and ensure that there is not inference between the device features and the mechanism. The second of these two parts (bottom illustration), is the protective bumper. This impact protective bumper wraps around the main casing, sitting within shallow recesses to ensure that it is secure but still sits slightly above the main casing. The protective bumper is likely to made out of an impact resistant material, such as silicone, in order to reduce the likelihood of damage to the main casing, and the components housed within it, in the event of a impact. This component needs to be easily removable, as the intention is that it will be available (separately from the main device) in a range of designs allowing the user to customise/upgrade their device. The hinge that holds the two main casings together is currently made up of four pins that are held within the main casing (one at the top and one at the bottom of each main casing) and two bars that hold these pins together (one at the top & one at the bottom).

January

Planning Perk Chart Creation Perk Chart Review Perk Chart Update Risk Plan

PDS Researcb Create Review Edit CAD & Sketching CAD Planning CAD Draw Up CAD Rendering Rework CAD Schematic Drawings Exploded Drawings Technical Drawlings Assembly Drawings Modellng Model Planning Material Sourcing Model Build Model Finish Testing Test Planing

Testing Set Up Testing Results Write Up Results Review Casing Dev Material Selection Sizing Aesthetics Ergonomics Mechanism Dev Limiting the functions Sizing Materials Electronics Dev Source Components Programming Circiut Layout Interface Dev Interface Reserach Interface Creation Refinement Manufacturing DFMA FMEA Costing Prototyping Planning Sourcing Materials Manufacture Assembly

Finishing

February

March T 6

April

PRODUCT DESIGN SPECIFICATION CONTENTS

1. Performance

1.1. Function

1.1.1. Battery Life

1.1.2. Screen Connectivity

1.1.3. Interface Set Ups

1.1.4. Portability

1.2. Appearance 1.2.1. Customisability

1 1

1.2.1.1. Design of the customisable parts 1 of the product

1.2.1.2. Changing the customisable parts 2 of the product 1.2.2. Screen

1.2.2.2. Ratio

1.2.2.3. Bezel

1.2.3. Suitable for the mechanism 1.3. Quality & Reliability

2 2 2

1.3.2. Life Span

This Product Design Specification is for a portable reading, research, or revision tool for post compulsary eduation, which can easily be used in a range of locations for short periods of time.

1.3.3. Maintainability

1.3.4. EU Directive on the sale of

1.3.5. Failure Analysis

The product is made up of two screens that are joined together by hinges on both the top and bottom of the product. These hinges allow the user to set up the screens in a variety of ways (as shown in the illustrations below). The interface of the product alters dependent on the set up and the users preferences.

1.3.6. Capabilities

1.3.6.1. Manufacture

1.3.6.2. Design & Development

1.3.6.3. Suppliers/Off-the-shelf parts

1.3.6.4. Assembly

INTRODUCTION

1.3.1. Product Design Specification

The main electronics/PCB within the device will be sourced, in line with the specification points, and then altered to enable the stated functions.

1.2.2.1. Size

Each screen will be enclosed in a hard plastic case (which the hinge is built into), and then covered with an interchangeable protective silicone bumper, which will be available in a variety of designs.

consumer goods and associated guarantees

1.3.7. Areas of concern

1.3.7.1. Transfer of Information

1.3.7.2. Speed

1.3.7.3. Battery Lifespan

1.3.7.4. Hinge Mechanism

1.4. Environment

1.4.1. Temperatures

1.4.1.1. Operating Temperatures

1.4.1.2. Storage Temperates

1.4.2. Humidity

1.4.3. Corrosion/Damage from

1.8.1. Operating Noise Level

3.4.2. Labeling

1.8.2. Audio output

3.4.3. Safety After Prolonged Use

2. Manufacture

3.4.4. Operating Instructions

chemicals 1.4.4. Damage in Transit 1.4.5. Storage Environment (Between

2.1. Process

Uses)

4. Acceptance 4.1. Inspection

11 11

1.4.6. Locations for Use

2.1. 1. Prototyping

1.4.7. Drop Impact

2.1.2. Variety of processes in production 9

4.1.1. Inspection in Production

2.1.3. Adaptability

4.1.2. Failure Rates

2.2. Materials

4.1.3. Failure of Product at Inspection 11

1.5. Costing 1.5.1. Required Landed Price

4.2. Standards & Testing

1.5.1.1. Device

2.2.1. Bumper

1.5.1.2. Bumpers (set of 2)

2.2.2. Casing

4.2.1. Screen Standards & Testing

2.2.3. Hinges/Mechanism

4.2.2. PCB Standards & Testing

4.2.3. Charging Standards & Testing

1.5.2.1 Device

2.3.1. Assembly complexity (Design for 9

4.2.4. Wireless Communication

1.5.2.2. Bumpers (set of 2)

1.5.2. Cost break down (product,

2.3. Assembly

packaging, shipping)

Standards & Testing

manufacture assembly)

2.3.2. Assembly Location

4.2.5. Switch Standards & Testing

1.5.3.1. Modeling

2.4. Packing & Storage

4.2.6. Electrical Fire Standards &

1.5.3.2. Testing (in development)

1.5.3.3. Final Prototype

1.5.3. Development/Set-up Costs

1.5.3.4. Tooling 1.6. Ergonomics

2.4.1. Storage of Excess Components & 9

Testing 4.2.7. Casing Standards & Testing

Product

2.4.2. Packaging for Shipment

4.3. Intellectual Property

2.4.3. Packaging construction

4.3.1. Competitors Patents

4.3.2. Intellectual Property applications 14

1.6.1. Dimensions

(protection)

1.6.1.1. Product casing

2.4.4. Packaging Copy

1.6.1.2. Buttons

2.5. Minimum Order Quantities

1.6.1.3. Screen

2.6. Delivery Date

5.1.1. Identifying Plastics

1.6.2. Weight

2.6.1. Final prototype

5.1.2. Disassembly

1.6.3. Force Required for Use

2.6.2. Lead Times

5.2. Legislation

1.6.3.1. Buttons

1.6.3.2. Set Up Changing

5. Disposal

5.1. Standards

3. Operation

5.2.1. Electrical Items (WEEE)

3.1. Installation

5.2.2. Batteries

3.1.1. Initial Product Set Up

5.2.3. Packaging

1.6.4.1. Resolution

3.1.2. Loading Documents to the

1.6.4.2. Brightness

1.6.4. Screen

Device 3.2. Use

1.6.4.3. Refresh Rate

1.6.4.4. Contrast

3.2.1. Document Storage

1.6.5. Interface

3.2.2. Compatibility

1.6.5.1. Consistency

3.3. Maintenance

1.6.5.2. Tasks/Processes

3.3.1. Repair

3.3.2. Interchangeable Bumpers

3.3.3. Battery

3.3.4. Upgrading Software

1.6.5.3. Feedback (information & warnings) 1.6.5.4. Appearance

1.7. Weighting

1.8. Noise

3.4. Safety 3.4.1. Legislation

11 11

1.1.4. Portability The final product must comfortably fit within an average sized day bag, meaning its footprint must be under 305 x 355mm and have a set up and clear away time of under 2 minutes. 1.2. Appearance 1.2.1. Customisability

PERFORMANCE 1.1. Function 1.1.2. Screen Connectivity 1.1.1. Battery Life The user should be able to use the product, carrying out standard tasks, for 4 hours (8 x the average 30min study session, enough for 2 days of standard use) before it runs out of battery*. * Each 30min test sessions should be made up of the following; 10 minutes browsing online, 10 minutes reading/ writing, 10 minutes emailing; both screens and wifi will be active throughout the session.

The product must be able to transfer the following between the screens; Power (inline with point 1.1.1.) for use and charging. Data at a speed of 12 Mbit/s (standard speed for USB 2.0). 1.1.3. Interface Set Ups Each set up must activate, through sensors rather than manual user input, the set ups shown in Figure 1.

Figure 1 : Set Up Guide

1.2.1.1. Design of the customisable parts of the product The interchangeable bumper part of the product must be available in at least 5 different colours/design, that appeal to young adults, aged 16-25, within the following categories; - Male - Female - Unisex 1.2.1.2. Changing the customisable parts of the product It must be possible for the user to remove one interchangeable bumper (FIGURE) and switch it with another (altering the appearance of the product) within 3 minutes. 1.2.2. Screen

Figure 2 : Dimension Restrictions the following restrictions; 1.2.2.1. Size The following documents must be readable from 400mm (+-50mm) (the distance generally chosen when reading a book (Pheasant, S. 1987)) on the devices screen in the stated set ups; - A4 text document when the 2 screens are pushed together - A5 text document in all set ups - Standard web page in all set ups 1.2.2.2. Ratio In order to view â&#x20AC;&#x2DC;Aâ&#x20AC;&#x2122; sized documents in their intended layout the ratio of the screens should be 1.41 : 1. 1.2.2.3. Bezel

The bezels around the screens should be minimal in size, particularly on the vertical edges for when the screens are tiled together, ideally fitting within the following restrictions (based on the bezel sizes of market competitors); - Inner vertical bezels should be less than 10mm - Outer vertical bezels should be less than 15mm - Top horizontal bezel should be less than 15mm - Bottom horizontal bezel should be less than 15mm 1.2.3. Suitable for the mechanism The form of the outer casing must not interfere with the mechanism/ hinge, therefore it needs to abide to

- Straight & completely parallel top and bottom edges - Straight & completely parallel inside edges - Radius of under 4mm on the inside corners - Radius of under 8mm on the outside corners 1.3. Quality & Reliability 1.3.1. Product Design Specification In order to gain maximum quality and reliability all points within this product design specification must be updated, referred to, and tested against throughout development and production. All revisions of this product design specification must be dated and stored for easy reference.

1.3.6. Capabilities 1.3.2. Life Span The life span on this product should be at least 3 years (960 hours, as per Figure 3), in this time it is estimated that the set up of the product will be changed 3840 times (as per Figure 4). Within this time it should be possible to easily implement new technologies/developments into the existing product (in manufacture). All tests should be carried out in accordance to this lifespan. 1.3.3. Maintainability As a dependable product, that students will rely on throughout their studies, it is important to keep maintenance to a minimum over itâ&#x20AC;&#x2122;s 3 year minimum life span (see point 3.3.) and ensure that any failures that happen within this time can be; Easily & safely repaired by the user in a short period of time (3 days to order and receive parts if necessary, and under 1 hour to fix) or Repaired by of professional in under a week for less than 50% of the products value.

Figure 3 : Product Life Span

This can be done by part reduction, component standardisation, modular design, and/or minimizing complexity.

1.3.4. EU Directive on the sale of consumer goods and associated guarantees The EU Directive 1999/44/EC states that all consumers within the EU must have the right to make a claim for faulty or misdescribed product for a minimum of two years. Therefore the product should remain fully working, or easily repairable, within this time (when subjected to recommended use in the environments stated in point 1.4.). 1.3.5. Failure Analysis Failure analysis in the form of FMEA, to discover and eliminate product failure within in recommended use and environments (point 1.4.5.), should be carried out throughout product development. If failure is deemed unavoidable, or to expensive to resolve, the risk/outcome of the failure in terms of; safety, cost, and probability, should be considered before deciding whether to proceed with the concept/feature.

1.3.6.1. Manufacture The capabilities of each manufacturers to meet the specified levels of quality must be proven through tested production samples, approved production samples must be securely stored and labeled for reference in the event of product/ component failure. Before investing in production samples from any manufactures the following must be considered, What machine/tools do they work with (are they capable of producing the quality specified)? Are they capable of maintaining the specified quality for both high & low production runs? What is the quality of existing products produced by them like? It is the manufacturers responsibility to ensure that the specified & approved quality requirements are abided to though inspection (see point 4.1.). 1.3.6.2. Design & Development

It is the responsibility of the manager to ensure that adequate time and resources are spend on each development area, in line with the GANTT chart & budget. Should extra time or resources be needed, in order to develop skills and capabilities before working on a specific task, the GANTT chart and budget should be updated accordingly. 1.3.6.3. Suppliers/Off-the-shelf parts The capabilities of each supplier to meet the specified levels of quality must be proven through tested production samples, approved production samples must be securely stored and labeled for reference in the event of product/component failure. Before working with a supplier the following must be considered, What quality control procedures do they have in place?

to ensure that any off-the-shelf parts abide to the specified & approved quality requirements though inspection (see point 4.1.). 1.3.6.4. Assembly Any assembly processes which directly affect the safety/quality of the product should be carried out under controlled conditions. These controlled conditions should include the following; documented work instructions, used of suitable and approved equipment, monitoring for components and processes, approval of assembled product against guidelines and production sample. 1.3.7. Areas of concern The following are areas of high concern, therefore there should be a strong focus on the quality and reliability of these areas throughout development. 1.3.7.1. Transfer of Information

What testing has the supplier already carried out on the component? Are they capable of maintaining the quality across different batches?

The product must be able to consistently transfer data and power between the two screens, as stated in specification point 1.1.2.;

It is the manufactures responsibility

â&#x20AC;&#x2DC;The product must be able to transfer

the following between the screens; Power (inline with point 1.1.1.) for use and charging. Data at a speed of 12 Mbit/s (standard speed for USB 1.0)â&#x20AC;&#x2122; In each set up, in all of the environments shown in section 1.4.5. This should be tested by subjecting the product to use in these environments, in each set up, for 100hours using either live testing or computer simulation. 1.3.7.2. Speed The average speed of the product should not drop by more than 20%, within its life span of 960 hours (see point 1.3.2.).

1.3.7.3. Battery Lifespan The battery capacity of the product should not drop by more than 20%, leaving it with 80% or more of its original capacity, within 350 charging cycles (inline with the deterioration rate of current lithium-ion tablet and smartphone batteries) (Carlstom, 2013).

Figure 4 : Mechanism Life Span

1.3.7.4. Hinge Mechanism

Figure 5 : Cost Break Downs

The hinge mechanism must be able to withstand 3840 set up changes within it’s life span (see point 1.3.2.) 1.4. Environment 1.4.1. Temperatures 1.4.1.1. Operating Temperatures The product should be able to work in temperatures between 0° and 35° C in line with similar products (Nguyen, 2014). 1.4.1.2. Storage Temperates The product should not be damaged (while off) by temperatures between -20° and 45°C in line with similar products (Nguyen, 2014). 1.4.2. Humidity The product should not be damaged by humidity of 5 percent to 95 percent noncondensing in line with similar products (Nguyen, 2014). 1.4.3. Corrosion/Damage from chemicals The product must be resilient to corrosion/damage from the following chemicals/products that it is likely to come into contact with; • • • •

Beauty products (moisturiser, make up, sun screen) Antibacterial sprays Rain (acidic) Dye from clothing/bag linings

1.4.4. Damage in Transit The packed product is likely to be exposed to, and therefore must be resilient against, vibration levels of up to 0.033 in X, 0.0613 in Y, 0.1218 m/ s^2 in Z in transit (Narayanamoorthy, 2008). 1.4.5. Storage Environment (Between Uses) The finished product is likely to be stored in the users bag (see point 1.1.4. for portability) before uses and therefore likely to be exposed to the following; • • • • • 17

Sharp objects such as key’s or pens that may scratch the device Small traces of dirt (crumbs) and liquid Force from being knocked (users bag bumping into hard objects) Force from being dropped (either into the bag or while in the bag) Force from items such as heavy books being places on top of the

•

device Low levels of vibration from walking/running

The values/effects of each of these points will need to be calculated and tested against throughout development.

The device must be low cost in comparison to the current market alternatives, with an initial purchase price of under £265 (the average cost of a tablet device). Therefore, based on the calculations (in Appendix 1), the required safe landed price (landed price plus 1-% for unforeseen costs) for the product is £66.78.

1.4.6. Locations for Use 1.5.1.2. Bumpers (set of 2) The user should be able to comfortably use the product for at least 45minutes in the locations shown in Figure 7. 1.4.7. Drop Impact As a handheld product that is likely to be dropped from chest height (approximately 1.45 metres for a 97.5% percentile male (Dreyfuss, 2002)) the product must be tested in line with BS EN 60068-2-75:1997 (Environmental testing - Part 2: Tests - Test Eh. Hammer tests) to ensure that a drop from this height does not result in catastrophic unrepairable failure. 1.5. Costing 1.5.1. Required Landed Price 1.5.1.1. Device

The bumpers must be priced in line with current tablet cases/bumpers, with a purchase price of under £30 (for 2). Therefore, based on the calculations (in Appendix 1), the required safe landed price (landed price plus 1-% for unforeseen costs) for the product is £7.56. 1.5.2. Cost break down (product, packaging, shipping) 1.5.2.1 Device The estimated device budgets (shown in Figure 5), based on costing from previous projects, have been assigned to each area (product, packaging, shipping) and must be worked towards; 1.5.2.2. Bumpers (set of 2)

The estimated bumper budgets (shown in Figure 5), based on costing from previous projects, have been assigned to each area (product, packaging, shipping) and must be worked towards; 1.5.3. Development/Set-up Costs The development and set up budgets (shown in Appendix 1) must be worked towards. Any changes in budget must be documented in the tables. 1.5.3.1. Modeling

The overall product budget for modeling is ÂŁ100, were possible components and material must be sourced free of charge (through suppliers/manufacturers). Modeling budget costs include; materials, tools, labor costs. A budget of all modeling costs must be kept up to date in the table (Shown in Appendix 1).

while in development is ÂŁ50, where possible all testing must be completed on site using the readily available facilities and materials. This testing (in development) budget costs include; materials (e.g. weights), tools, data costs, and participant fees. A budget of all development testing costs must be kept up to date in the table (Shown in Appendix 1). 1.5.3.3. Final Prototype

1.5.3.2. Testing (in development) The overall product budget for testing

Figure 6 : Elements

Figure 7 : Locations for Use

The overall budget for the final prototype is ÂŁ150, were possible

Figure 8 : Ergonomic Points 19

components and material must be sourced free of charge (through suppliers/manufacturers). This final prototyping budget costs include; materials, tooling, labor, and component costs. A budget of prototyping testing costs must be kept up to date in the table (Shown in Appendix 1). 1.5.3.4. Tooling The cost of tooling should be kept to a minimum, DMFA techniques should be used to reduce the number of components that need to be tooled. 1.6. Ergonomics 1.6.1. Dimensions 1.6.1.1. Product casing The product must be sized between 110mm x 160mm & 165 x 240mm, as these dimensions were deemed most user friendly through testing. Additional user testing on the size of the final product, including it’s thickness, should be carried out during development in order to ensure that the product is of a suitable size for both use and storage/ portability. 1.6.1.2. Buttons All buttons on the product should have a diameter of between 10 – 25mm, a displacement of between 2.8 – 11mm, and a separation (from other buttons) of 13 – 50mm (Pheasant, S. 1987) 1.6.1.3. Screen The screen (single) must be at least 100mm x 150mm & 155 x 230mm, as these dimensions were deemed most user friendly through testing. Additional user testing on the size of the screen, should be carried out during development in order to ensure that the screen is suitable for use without being too large to be considered portable. 1.6.2. Weight As the device will be operated /held with one hand, while not rested on a surface, its overall weight must not exceed 2kg (Dul, J. 2001). 1.6.3. Force Required for Use 1.6.3.1. Buttons All buttons on the product should require a focus of between 2 – 6

Newtons to be activated (Pheasant, S. 1987) in order to be deemed ergonomic. 1.6.3.2. Set Up Changing Changing the set up of the device should require less than 22N, the suitable focus for light wrist & finger operation (Pheasant, S. 1987)

operations at any time. 1.6.5.3. Feedback (information & warnings) The interface must provide the user with warnings, reminders, and feedback when necessary, provided in a user centered way, by; • •

1.6.4. Screen 1.6.4.1. Resolution The screen resolution should be as high as possible without sacrificing battery life & screen refresh rate. As a guideline the current market competitors have resolutions of between 165 - 326 ppi. 1.6.4.2. Brightness The brightness of the screen should be 250 cd/m2 (the recommended brightness for normal lighting conditions (Bos, 2013)). But should adjustable between at least 200 cd/ m2 (for dark conditions) and 400 cd/ m2 (for bright conditions).

• • •

1.6.5.4. Appearance The interface must; •

•

• 1.6.4.3. Refresh Rate The refresh rate of the screen should be no lower than 72 Hz (WikiEducator, 2008).

Using real-world metaphors Giving feedback that confirms the users input Providing status indicators Not using distracting techniques such as flashing messages. Not displaying important information for limited periods

•

Not use more than 4 different colors, font sizes, or font styles on a single screen. Use colours appropriately (for example red for danger and green for accept). Not significantly change in appearance/layout from screen to screen. Allow some degree of customization of screen layout, appearance, icons etc Have plenty of empty space around text boxes (ideally 50%)

1.7. Weighting 1.6.4.4. Contrast The contrast level of the screen should be at least 450:1 (number of gray tones) in order to be consider as ‘adequate for normal use’. Although higher values are recommended (Bos, 2013). 1.6.5. Interface In order to be deemed ergonomically acceptable the interface of the product must abide to the following points (Cornell University, 2013); 1.6.5.1. Consistency The interface should be consistent (in behavior, terminology, icons, and colour) across all screens.

The product must be evenly weighted, with a maximum weight difference of 10% between the weight of the top half of the product and the bottom half of the product. 1.8. Noise 1.8.1. Operating Noise Level The general operating noise of the device sound not exceed 35dB, the maximum noise level to avoid annoyance to people doing ‘concentrated intellectual work’ in a library. Any short term set up noise created, such as opening the device and turning it on, should not exceed 50dB (Dul, J. 2001). 1.8.2. Audio output

1.6.5.2. Tasks/Processes Tasks/processes should be made simplier by; • • • • • •

Breaking them into smaller steps Using familiar icons Making them linear. Providing cues Requiring minimal user input Allowing the user to exit from all

The user should be able to adjust any audio outputs of the device to a level between 0 - 70dB(A), the maximum audio output of the device should not exceed 85dB(A) (Mansfield, 2013).

before use/packing. 2.4.2. Packaging for Shipment The supplier must pack the product in accordance to each of the retailers/ buyers requirements (including product per case, box size, & sticker requirements), packing requirements must be specified with the supplier before orders are placed.

MANUFACTURE 2.1. Process

1.6.2. (Device weight) & 1.4.6. (Drop Impact) to be met.

2.1. 1. Prototyping 2.2.2. Casing The final prototype must be suitable for manufacture within the university facilities. Which include, but are not limited to, the following; • • • • • •

• •

Makerbot Replicator x2 3D printer Stratasys Fortus 250mc 3D printer Zcorp 2510 powder/resin 3D printer Laser cutter Plastics oven & vacuum former Woodwork workshop (includes bandsaws, sanders, drills, lathe, etc) Electronics workshops (solder irons, drills etc) Metal workshop (CNC machines, welders ,etc)

2.1.2. Variety of processes in production The number of processes required to create all the products components must be minimal therefore limiting the number of different manufactures needed throughout production.

The materials used for the main the casing must allow points 4.2.7. (Casing Standards & Testing), 1.6.2. (Device weight) & 1.4.6. (Drop Impact) to be met. 2.2.3. Hinges/Mechanism The materials used for the hinge must allow point 1.3.2. (Life Span) to be met without having a significantly negative impact on 1.6.2. (Device weight) & 1.4.6. (Drop Impact). 2.3. Assembly 2.3.1. Assembly complexity (Design for manufacture assembly) In order to reduce the assembly time for each unit design for manufacture assembly techniques must be applied to the whole design. Ideally the assembly time for a single unit of the product should be less than 10 minutes. 2.3.2. Assembly Location

2.1.3. Adaptability As the consumer electronics market is extremely fast moving, the processes used should be adaptable allowing any product develops to be implemented in product with maximum ease. 2.2. Materials

2.2.1. Bumper The bumper must made of a material that has significant elasticity to be stretched around the device using less that 45N force but can resist deformation over the lifespan of the product. It must also allow points 4.2.7. (Casing Standards & Testing), 21

The assembly location must be central to all the other suppliers/ manufacture for ease of production. 2.4. Packing & Storage 2.4.1. Storage of Excess Components & Product The supplier will need to provide secure storage, that prevents damage or deterioration, for excess components and product. Any product or components that are in storage need to be inspected on a monthly basis (at a ratio of 1:100), and any product/components that have remained in storage for over 3 months must be fully tested/inspected

The following points should be considered in order to meet costing (point 1.5); • • •

What is the ratio of product size to packaging size? Is their any excess weight that could be removed?, Does the packaging tessellate?

2.4.3. Packaging construction (protection) In order to avoid damage in transit/ storage, the construction of the packaging should allow adequate protection in line with point 1.4.4. (Damage in Transit). 2.4.4. Packaging Copy The packaging should supply potential consumers with all necessary product & safety information in line with point 3.4.2. (Labeling). 2.5. Minimum Order Quantities All parts should be available at minimum order quantities under 5,000, if this is not possible the impact of ordering at higher quantities will need to be consider before either ordering the higher quantity or making design changes to avoid them. 2.6. Delivery Date 2.6.1. Final prototype Development must be completed and a final prototype must be made by the 16th May, this should be achieved in line with the product plan/Gantt chart. 2.6.2. Lead Times Lead times for components and materials must be built into all ETA’s. The lead time on orders of the final product should not exceed 6weeks.

formats; • • • •

3.3. Maintenance 3.3.1. Repair

OPERATION 3.1. Installation

3.1.1. Initial Product Set Up It must be possible for the user to set up the software of the final product, to suit their needs, in less than an half an hour without the need for another device. 3.1.2. Loading Documents to the Device The user should be able to add documents, from the following locations, to the device in under 3 steps (from locating the document); student network, webpage, ebook

pub (ebook) PDF Word, Excel, & PowerPoint documents avi, mpeg-4 (video)

store, and email.

3.2. Use 3.2.1. Document Storage The product must be able to hold 1GB of documents (over 2,000 large B&W e-books), but should ideally have the ability to hold 16GB of documents (inline with the current market average). 3.2.2. Compatibility The product must allow the user to view documents of the following

Figure 9 : File Compatibility

It must be possible to repair/replace parts of the product, specifically the mechanism pins, in line with point 1.3.3. (Maintainability). 3.3.2. Interchangeable Bumpers The interchangeable bumpers must be of low maintenance in terms of; cleaning (wipe clean in under 2 minutes without removing), & use (must not have to remove the bumper to access any of the devices features). 3.3.3. Battery The battery must be of low maintenance in line with points 1.1.1. (Battery Life) & 1.3.8.3. (Battery Lifespan). 3.3.4. Upgrading Software Software upgrades should be made

available to the user, but should not be compulsory or take longer than 1 hour to download (via wifi) and install. 3.4. Safety

• • • • • •

Ports/Switches/Controls Disposal Cleaning Safety Power Materials

3.4.1. Legislation The final project must be both ROSHH & REACH compliant. 3.4.2. Labeling For ease of use and maintenance all relevant features/details, including;

Should be marked, on the packaging and/or product, using graphical symbols in line with ‘BS EN 604171:1999 - Graphic symbols for use on equipment - Part 1’. 3.4.3. Safety After Prolonged Use

4.1.1. Inspection in Production 10% of assembled product will need to be inspected against the specified requirements and signed off, before being packed for delivery. This process should be carried out in line with BS5750 : Part 1 ‘ Quality Systems’. The sign off status of the product should be shown on the product in the form of a sticker, which states a sign off code, and can be linked back to the exact production run and inspection authority, incase of recall. 4.1.2. Failure Rates If more than 1% (1 in 100) products, from the 10% inspected, fail inspection all products will need to be inspected. If the failure rate remains at 1% or more once all product has been inspected the batch will need to be rejected and production halted while the failure is inspected and action (design or production) is taken to resolve the issue. 4.1.3. Failure of Product at Inspection 23

In the case of inspection failure

3.4.4. Operating Instructions Full operating instructions, that include safety and disposal information, should be supplied to the consumer alongside the product.

Requirements for surface mount soldered assemblies’. The quality of the finished PCB’s must meet the requirements of ‘IPC-A-610E:2010, Acceptability of Electronic Assemblies’.

ACCEPTANCE 4.1. Inspection

FMEA should used, in line with point 1.3.5. (Failure Analysis), to ensure that the product remains safe even after heavy use, in the event that a failure could be dangerous safety features (that may cause catastrophic failure) should be built into the product.

the product may be reworked and resubmitted for inspection. No product will be accepted as reconditioned (even if the failed product is deemed safe for use), meaning that any failed product can cannot be reworked must be disposed of. 4.2. Standards & Testing Please see Figure 11 for a list of all relivent Briish Standards. 4.2.1. Screen Standards & Testing The screens must be tested for the following; edge strength, surface strength, surface impact resistance, scratch performance, retained surface strength, resistance to indentation cracking. These tests must be carried out in accordance to ‘BS EN 6174740-1 Liquid crystal display devices, Part 40-1 Mechanical testing guidelines for display cover glass for mobile devices’. 4.2.2. PCB Standards & Testing The PCB mounted components/ connects must abide to and be tested against ‘BS EN 611912:2013 -Printed board assemblies Part 2: Sectional specification -

As a handheld product ‘electronic products that can be conveniently stored in a pocket and used while held in user’s hand’ that is likely to be dropped ‘handheld electronic products are more prone to being dropped during their useful service life because of their size and weight’, must abide to and be tested against ‘IEC/PAS 62050:2004 - Board level drop test method of components for handheld electronic products’ 4.2.3. Charging Standards & Testing The product should be charged using a Micro USB to USB cable (inline with the European Council’s universal charger recommendations) and therefore must abide to ‘BS EN 62680-3:2013 - Universal serial bus interfaces for data and power - Part 3: USB battery charging specification, Revision 1.2’. 4.2.4. Wireless Communication Standards & Testing The products wireless systems must abide to ‘COUNCIL RECOMMENDATION on the limitation of exposure of the general public to electromagnetic fields (1999/519/EC)’ and ‘BS EN 50566:2013 - Product standard to demonstrate compliance of radio frequency fields from handheld and body-mounted wireless communication devices used by the general public (30 MHz — 6 GHz)’. In order to ensure compliance with these standards the product must be tested in line with ‘BS EN 62479:2010 - Assessment of the compliance of low power electronic

Figure 10 : Acceptable Failure Rate (1%)

and electrical equipment with the basic restrictions related to human exposure to electromagnetic fields (10 MHz to 300 GHz)’. 4.2.5. Switch Standards & Testing All user operated switches within the product must abide to and be tested against ‘BS EN 61058-1:2002 - Switches for appliances - Part 1 : General requirements.’ 4.2.6. Electrical Fire Standards & Testing The products PCB and casing should be tested, for fire safety, inline with ‘BS EN 60695-2-13:2010 - Fire hazard testing - Part 2-13’ using the hot-wire based test method at 650 °C to ensure that the product does not; ignite or show signs of sustained and continuous flaming combustion (with no single flame lasting longer than 5 seconds)

which focus’ on ‘protection provided by enclosures for electrical equipment with a rated voltage not exceeding 72.5kV’;

Protection against access to hazardous parts with; 4. 1. 2. 3. 4.

The back of a hand With a finger With a tool With a wire.

Protection against objects, including;

solid

foreign

enclosure is tilted at any angle up to 15 on either side of the vertical. Water sprayed at an angle up to 60 on either side of the vertical shall have no harmful effects (simulating rain) Water splashed against the enclosure form any direction shall have no harmful effects.

Each point should be tested using the British Standard recommended test methods and environments. 4.3. Intellectual Property

2. 3.

Ingress of dust is not totally prevented, but dust shall not penetrate in a quantity to interfere with satisfactory operation of the apparatus or to impair safety. An object of 2.5mm diametre shall not penetrate at all An object of 12.5mm diametre shall not fully penetrate

4.2.7. Casing Standards & Testing

4.3.1. Competitors Patents The Intellectual Property of significant design features should be researched to ensure that they are not covered by any existing patents. The following patents should be considered throughout the design process to ensure that they are not breached;

Protection against water, including; The casing (that holds the PCB) must be designed inline with and tested against the following points within ‘BS EN 60529:1992 - Degrees of protection provided by enclosures’

1. 2.

•

Tablet computer with option for one or two screens - US 20120086658 A1 (Payam Moradian, 2010).

•

Electronic dual screen personal tablet computer with integrated stylus - US D631043 S1 (Microsoft, 2010)

•

Portable computer for dual, rotatable screens - US 20080062625 A1 (Batio, 2007)

•

Multi-fold mobile device with configurable interface US 20100064244 A1 (Qualcomm Incorporated, 2008)

Vertically falling drops shall have no harmful effects Vertically falling drops shall have no harmful effects when the

4.3.2. Intellectual Property applications IP applications should be made for the following features of the product;

Figure 11 : British Standards

•

The hinge/mechanism in the form of a Patent

•

The interface (how the two screens interact together) in the form of a Patent

•

The forms of the case & bumper in the form of Design Rights

•

Any unique prints that are applied to the surface of the bumpers in the form of Design Rights

http://wikieducator.org/Ergonomics. Last accessed 12th Feb 2014. Carlstom, E. (2013). Constant Charging How it Affects your Smartphone’s Battery - See more at: http://www.mobilesecurity. com/articles/479-constant-chargingh o w - i t - a f f e c t s - yo u r - s m a r t p h o n e s - b a t t e r y # s t h a s h . I 1 z Z c m 7 P. d p u f. Available: http://www.mobilesecurity. com/articles/479-constant-charginghow-it-affects-your-smartphone-s-battery. Last accessed 10th Feb 2014.

DISPOSAL

5.1. Standards

onto someone that is authorised to deal with it.

5.1.1. Identifying Plastics 5.2.2. Batteries All plastic components must be clearly marked in line with the American Society of the Plastics Industry plastics coding system. 5.1.2. Disassembly In order to make the product easier to break down for disposal DFMA techniques must be applied in line with point 2.3. (Assembly). 5.2. Legislation The product must be designed in line with all UK disposal legislation, including;

In order to ensure that the product does not pose a risk to the environment or human health when disposed of, the batteries used the the product must abide to the ‘EU’s Waste Legislation on Batteries & Accumulators’. Therefore meaning that the batteries must not have more than; • • •

0.0005% mercury by weight (and not exceed 25mg) 0.025% cadmium by weight 0.4% lead by weight

5.2.3. Packaging 5.2.1. Electrical Items (WEEE) In order to reduce the amount of untreated waste electrical and electronic equipment that goes to landfill and instead ensure that it is dealt with properly ‘Waste Electronic and Electrical Equipment Regulations 2006 (WEEE)’ must be abided to. Meaning that at least one of the following is an option at ‘endof-life’: •

•

Taking the product to a repairer who carries out the repair and returns the equipment to them the user. Giving the existing product back to the retailer when a replacement product is purchased/delivered. Donating the product to a charity or community workshop, who can refurbish the product. Returning the product to the retailer under a retailer returns policy.

Any WEEE must be stored properly in order to prevent it from harming the environment before being passed

All packaging (industrial and commercial) for the final product must be designed in line with ‘The Packaging and Packaging Waste Directive (94/62/EC)’, to ensure that; • • • •

Packaging is minimised. Packaging be designed for recovery and re-use. UK recovery targets for waste packaging are met. Heavy metals in packaging to be restricted

References Batio, J. (2007). US 20080062625 A1. Available: https://www.google.com/patents/ US20080062625?dq=dual+screen+tablet& hl=en&sa=X&ei=lGEpU8HrHOG64ATqYC4BA&ved=0CGgQ6AEwBzgU. Last accessed 16th February 2014. Bos, H. (2013). Monitor ergonomics. Available: http://www.bakkerelkhuizen. com/ergonomics/monitor-ergonomics/. Last accessed 12th Feb 2014. WikiEducator. (2008). Ergonomics. Available:

Cornell University. (2013). Ergonomics Guidelines for Interface Design. Available: http://ergo.human.cornell. edu/ahtutorials/interface.html. Last accessed 12th Feb 2014. Dreyfuss, H et al (2002). The Measure of Man and Woman: Human Factors in Design. New York: John Wiley & Sons. Dul, J et Al (2001). Ergonomics For Beginners. 2nd ed. London: Taylor & Francis. Mansfield, N. (2013 ). Characteristics of noise. Available: http://www. ergonomics4schools.com/lzone/noise. htm. Last accessed 12th Feb 2014. Microsoft. (2010). US D631043 S1. Available: https://www.google.com/ patents/USD631043?dq=dual+screen+ tablet&hl=en&sa=X&ei=3F8pU_-cNM 3c4QSIhIGwBg&ved=0CEgQ6AEwAg. Last accessed 16th February 2014. Narayanamoorthy, R et al (2008). Determination of Activity Comfort in Swedish Passenger Trains. India: Indian Institute of Technology Roorkee. Nguyen, N. (2014). How to Keep Your Phone From Freezing to Death. Available: http://www.geeksugar.com/iPhoneTemperature-Limits-27906464. Last accessed 12th Feb 2014. Payam Moradian. (2010). US 20120086658 A1. Available: https:// www.google.com/patents/US201200866 58?dq=dual+screen+tablet&hl=en&sa= X&ei=3F8pU_-cNM3c4QSIhIGwBg&v ed=0CGoQ6AEwBg. Last accessed 16th February 2014. Pheasant, S (1987). Ergonomics Standards & Guidelines for Designers. Milton Keynes: British Standards Institution. Qualcomm Incorporated. (2008). US 20100064244 A1. Available: https://www. google.com/patents/US20100064244. Last accessed 16th February 2014.

DEVELOPING THE MECHANISM

1. GOALS

The first area for development is the hinge mechanism, this mechanism holds the two main casings together and is currently made up of four pins that are held within the main casing (one at the top and one at the bottom of each main casing) and two bars that hold these pins together (one at the top & one at the bottom). The aims for this area of development are to; •

Create a mechanism that allows all the functions stated in specification point 1.1.3.

•

Ensure that the mechanism is ergonomic, as stated in specification point 1.6.

•

Ensure the mechanism is strong enough to withstand use, as stated in specification point 1.3.2. (Life Span), 1.3.7.4. (Hinge Mechanism), & 1.4 (Environment)

•

Create a mechanism that allows data & power to be passed through it, in line with specification point 1.3.7.1. (Transfer of Information)

These aims will be met using methods such as; research, sketching, modelling, CAD, FEA, material selection (CES Edu-pack), and testing.

Figure 1 : Current Hinge Design 27

MODELLING Model No : 01

Aim : To test the functionality of the initial hinge design. Method : 1. Cut the design into 2mm layers. 2. Model each layer in Solidworks and export as a DXF file (from top view). 3. Laser cut the layers out of 2mm MDF using the DXF file. 4. Cut the hinges bar out of 1mm acrylic using a scalpel. 5. Drill 2mm holes in either end of the bar. 6. Using PVA glue the layers of MDF

together (sandwiching the bolts for the hinge in the middle layer). Place the hinge bar onto the bolts and secure in place with a washer & nut.

Materials : • 2mm MDF sheet • 1mm Acrylic sheet • 4 x 1.5mm bolts, washers & nuts • PVA Pro’s : • Easy to produce • Can easily change the bar • Allows all the specified functions • Very smooth set up changes Con’s : • Slight movement vertically • Can easily be jogged out of position • Not very intuitive Conclusion : The one track, one fixed hinge method works very well but needs to be developed in order to make the set up changes more secure and intuitive. Currently there it too much room for movement in the track meaning; the pin can move in all directions rather than just horizontal along the track, and it can easily be jogged out of position.

Model No : 02 Aim : To eliminate over movement within the mechanism. Solution : Add blockers around the edge of the runners on both the top and bottom of the main casing. The blocker should stop the bar from travelling along unnecessary edges, therefore limiting the movement. Method : 1. Cut the design down into shorter, quicker to print form. 2. Model each part in Solidworks (ensuring the main body is in two parts to be assembled). 3. Assemble the model in Solidworks assembly to ensure all parts fit. 4. Export as a STL, load onto the Makerbot PC and add to the print queue list. 5. Once the part has printed remove all the support material. 6. Place the hinges within the bodies and secure closed with screws. 7. Secure the hinges together using the bars and secure in place using the stoppers. Materials : • 12 x Makerbot 3d printed parts • 6 x short 1.5mm bolts

Pro’s : • Can easily change the bar • Less likely to be jogged out of position • Very smooth set up changes • Limited to the specified set ups • More intuitive Con’s : • Still too much movement vertically • Too much of a gap between the screens when positioned behind one another. Conclusion : The set up changes are more secure, intuitive, and limited to the intended set ups. There is still too much room for movement in the track meaning; the screens can be moved vertically away from one another and there is a large gap between the devices when the are positioned on top of one another. This over movement is mainly due to tolerances and distance minimum distance between the pins when laid flat next to each other being too large.

Model No : 03 Aim : To limit; the vertical movement within the mechanism and gap the between the screens when positioned behind one another. Solution : Move the cut out slot for the bar from the top of the product to the back, therefore meaning the pins are secured at both the top and bottom therefore avoiding over movement. Method : 1. Cut the design into 2mm layers. 2. Model each layer in Solidworks and export as a DXF file (from top view). 3. Laser cut the layers out of 2mm MDF using the DXF file. 4. Cut the hinges bar out of 1mm acrylic using a scalpel. 5. Drill 2mm holes in either end of the bar. 6. Using PVA glue the layers of MDF together (sandwiching the bolts for the hinge in the middle layer). 7. Place the hinge bar onto the bolts and secure in place with a washer & nut. Materials : • 2mm MDF sheet • 1mm Acrylic sheet • 4 x 1.5mm bolts, washers & nuts • PVA

Pro’s : • Less likely to be jogged out of position • Smooth set up changes • Limited to the specified set ups • Intuitive Con’s : • More difficult to manufacture and assembly • Still some movement vertically (although greatly reduced) • Too much of a gap between the screens when positioned behind one another. Conclusion : Although the vertical movement was reduced it is still slightly apparent, the remaining vertical movement is mainly due to tolerances and the length of the pins and bars which can be further refined.

1. Introduction

FEA

These tests aim to investigate the maximum stress levels within the hinge when the pins are pulled away from one another. Although pulling the pins away from one another is not within the products intended use, it is possible that the user may accidentally pull on the hinge using excess force (while, for instance, pulling the magnets away from one another to change the set up, or pulling the product out of their bag). This report will focus on whether such force being applied to the hinge causes failure (the maximum stress within the product, exceeds the materials yield). Using structural design techniques and material knowledge (from CES Edupack) the aim is to refine the design of the pins and/or bar, not only ensure that they do not fail but also to gain a safety factor of 1.5 or above in all parts. 2. Model Set Up 2.1. Basic Geometry The main geometry of the hinge consists of 2 pins (as shown in Figures 3) and are joined together with a bar (as shown in Figure 2). The cylindrical base of each pin is 3mm in diameter and 1mm in height with 0.2mm fillet on the edges; on top of this base sits a cylindrical pin which is 1.5mm diameter and 8mm in height which allow has a 0.2mm fillet on its top edge. The bar that joins these pins is 16mm x 4mm x 1mm, has 2mm fillets on either end and 0.4mm fillets on the top & base; at either end of the bar there are 2.2mm diameter holes for the pins to slot into. 2.2. Idealisation All the features that are currently in the bar and pin will influence its structural strength, and therefore no features will be removed; but because the model is symmetrical it will be cut in half vertically in order to reduce the models run time. The outer casing of the product will not be included in the model as it is specifically the pins & bar that are being testing, but may be tested at a later date. 35

Figure 1 : Parts & Material Properties 2.3. Material Properties All parts within hinge will be made out of a stainless steels, this is because they are likely to be used in a wide variety or environments some of which may be damp or humid, and they are likely to be subjected to high levels of force and therefore need a high yield strength.

2.2. Idealisation) this force will be halved to 45N, which is equivalent to the full 90N being applied over the whole model. This force will be applied to the non-fixed pin, running parallel to the bar and directed as to pull away from the other pin (see Figure 4). 2.5. Mesh

The material properties for the initial test can be seen in Figure 1, all material property values were taken from CES Edu-Pack. These materials may be changed depending on the results of the tests. 2.4. Loads The standard load that will be applied to this model is based around information gained from The International Encyclopedia of Ergonomics and Human Factors (Karwowski, 2000) states that â&#x20AC;&#x2DC;hand forces should not exceed 45 Newton. This is also in line with the study by McGorry et al (McGorry, 2001), which showed that a single hand could only applied a maximum force of 45N on a blunt object (while gripping). Because the force being replicated is applied by 2 hands, both applying the same amount of force parallel to each other but in opposite directions, a force of 90N will be applied (2 x the maximum 45N force that can be applied by hand). Because in the test this force is only being applied to half the model (see point

As the parts within the model are quite small a fine mesh of 1mm will be used on all faces. 2.6. Restraints (Fixings) In order to correctly model the interaction between the pins & bar they need to be assembled to replicated that of the final product (while in a position that replicates that of the situation being testing). To do this the outside face of the pins need to be tangent to the far inside edge of the bar holes; the pins need to be coincident on their bases so they are the same way up and level; and the distance between the base of the pin and the base of the bar needs to be 6mm. To replicate the movement of pulling the pins apart the base of one of the pins need to be fixed and the base of the other need to be a roller fixing. To ensure that the pins and bar do not move up or back during the test roller fixings were applied to all the back facings and the top face on the bar.

Figure 2 : Initial Bar Technical Drawing

Figure 3 : Initial Pin Technical Drawing

Figure 4 : Test Set Up

In order to replicate the contact between the pins and the bar surface to surface contact sets (no penetration) were applied to the inside face of the bar holes and the outer face of the pin, this was done on either end of the model. A global contact of â&#x20AC;&#x2DC;No Penetrationâ&#x20AC;&#x2122; was set to all the parts. These mates & fixings are shown in Figure 4. 3. Initial Test 3.1. Stress Levels These tests show that the highest levels of stress are at the base of the pin where the main body of the pin joins the base, with this area being subjected to up to 1742.6 MPa of stress (see Figure 5). 3.2. Evaluation This maximum level of stress is almost 3 times higher than the 620 MPa yield strength of the chosen material. The area of highest stress suggests that design changes should be focused on this join, by filleting the edges on this join the maximum levels of stress should be reduced.

Figure 5 : Initial Design Results 4.1. Design Changes In order to reduce the levels of stress in the join between the base and pin (where the highest levels of stress were recorded in the initial test) a 0.5mm fillet was applied (see Figure 6). 4.2. Stress Levels This test showed that the highest levels of stress moved up the pin to approximately half way between the base the bar, with this area being subjected to up to 1672.2 MPa of stress (see Figure 6). 4.3. Evaluation This maximum level of stress is still over 2 times higher than the 620 MPa yield strength of the chosen material. Although applying the fillet reduced the level of stress in the join there are still extreme levels of stress in the pin itself, therefore further design changes, that focus on the main body of the pin, are going to be carried out.

Figure 6 : Revision 02 Results

5. Redesign 02 5.1. Design Changes In order to reduce the levels of stress in the main body of the pin (where the highest levels of stress were recorded in the previous test) the pins diameter was increased by 0.5mm (see Figure 7). 5.2. Stress Levels This test showed that the highest levels of stress moved back down the pin to just above the fillet, with this area being subjected to up to 737.2 MPa of stress (see Figure 7). 5.3. Evaluation This maximum level of stress is slightly higher than the 620 MPa yield strength of the chosen material. Although increasing the diameter of the pin reduced the level stress by over half, the hinge still fails. The highest level of stress remained in the pin and therefore further design changes, focusing on this area, are going to be carried out.

Figure 7 : Revision 03 Results 6. Redesign 03 6.1. Design Changes In order to reduce the levels of stress in the main body of the pin (where the highest levels of stress were recorded in the previous test) the height of the pins was reduced by 2mm (see Figure 8). 6.2. Stress Levels This test showed that the highest levels of stress moved onto the inside edge of the bar, with this area being subjected to up to 542.2 MPa of stress (see Figure 8). 6.3. Evaluation This maximum level of stress is under the 620 MPa yield strength of the chosen material but only give a safety factor of 1.14. Although the design changes have reduce the levels of stress to less than the materials yield strength they have not reduced the stress enough to gain the safety factor of 1.5 or above, therefore a possible material change is going to be researched in order to achieve a higher safety factor. 7. Final Design 7.1. Design Changes 39

Figure 8 : Revision 04 Results

Although the form of the pin was not

Figure 10 : Final Results

Figure 9 : Final Design changed, in order to gain a higher safety factor the material of the pin was changed to Stainless steel, Aus, Nitronic 50, xm-19, Wrought, Cold drawn which has an average yield strength of 1270 MPa (see Figure 9). To review the material selection process be see the following page. 7.2. Stress Levels This test showed that the highest levels of stress remained in the inside edge of the bar, with this area being subjected to up to 545 MPa of stress (see Figure 10), in line with the previous test results.

7.3. Evaluation This maximum level of stress is under the 1270 MPa yield strength of the new material and gives a safety factor of 2.33 which is over the goal of 1.5. 8. Conclusion These tests have shown that by redesigning the pins it was possible to reduced the maximum levels of stress by over 65%, enough for the hinge to be able to withstand the calculated extreme force of 90 Newtons. Although these changes did not allow a sufficient reduction in stress for a suitable safety factor to be met when using the initial material it did reduce

the stress enough for a suitable alternative material to be found. The highest levels of stress are now based in the bar, which in the event of breakage is external from the main casing and can be easily replaced. References Karwowski, W (2000). International Encyclopedia of Ergonomics and Human Factors. Kentucky: CRC Press. McGorry, R (2001). A system for the measurement of grip forces and applied moments during hand tool use.. Applied Ergomonics: NCBI.

MATERIALS

A material selection process was used to find a material that would allow the hinge to have a safety factor of over 1.5 when being subjected to an extreme force of 90 Newtons (see FEA report on previous pages). The price and yield strength were plotted against one another in order to ensure that the material chosen was the best value for money. Then limits were applied (see Figure 1), including a yield strength limit (which was calculated by times the maximum stress level in the FEA test by the safety factor), to ensure that only suitable materials were shown on the graph.

Figure 1 : Material Restrictions

TABLE

Figure 2 : Material Properties

After all the limits had been applied there were 8 materials left on the graph to choose from (see Figure 3). The properties of these materials were then put into a table for comparison (Figure 2), from which it was decided that the most suitable material would be â&#x20AC;&#x2DC;Stainless steel, Aus, Nitronic 50, xm-19, Wrought, Cold drawnâ&#x20AC;&#x2122; because it met all the limits at a lower cost than the alternatives.

Figure 3 : Results Graph

CONNECTIVITY

In order for the product to function correctly power & data needs to be transferable between the two main bodies (each screen). A ‘research, model, test’ method was used in order to investigate four different connection methods that would work across/through the hinge, and then choose the most effective to be used in production. Wireless forms of connectivity were briefly investigated, but a decision against further investigation into these methods was made due to cost, development, and battery concerns. The following paragraphs explain each method and the associated pros and cons. Videos of the testing process can be viewed on the online portfolio.

CONDUCTIVE FILIMENT

• •

Method

• •

This filiment is a conductive elastomer which is made from ABS that is full of conductive particles. This conductive plastic could be used in the same way as the copper track and conductive tape by running it along the base of the track. Again, the hinge pin will have to be very carefully toleranced or redesigned to ensure that there is constant contact between the base of the pin and the base of the runner.

•

Con’s •

•

Pro’s •

Easy to assemble Doesn’t require the hinge runner to be open (which could allow dirt & water into the main casing) Easy to replace (just add new tape) Only need to pass through one of the runners (top or bottom) Impact and corrosion resistant

The pin could easily come loose from the track/tape meaning loss of power/data to the second screen Being able to access the track/tape (which will have power running through it) is a safety risk More expensive than the other options.

COnductive tape Method Similar method to copper track, conductive tape is stuck along the base of the runner hinge, which will then make contact with a conductive base (as tape) on the hinge pin. Wire will run from the conductive tape to the main circuit and from the pin base through the hinge to the extra screen to complete the circuit. The hinge pin will have to be very carefully toleranced or redesigned to ensure that there is constant contact. Pro’s •

Low cost & easy to assemble

• • •

Doesn’t require the hinge runner to be open (which could allow dirt & water into the main casing) Extremely easy to replace (just add new tape) Only need to pass through one of the runners (top or bottom)

Con’s • • •

Tape will be open to the elements and may corrode/come away over time The pin could easily come loose from the track/tape meaning loss of power/data to the second screen Being able to access the track/tape (which will have power running through it) is a safety risk

Copper track

• •

Method Running a copper track along the base of the runner hinge, which will then make contact with a copper base on the hinge pin. Wire will run from the copper track to the main circuit and from the pin base through the hinge to the extra screen to complete the circuit. The hinge pin will have to be very carefully toleranced or redesigned to ensure that there is constant contact between the base of the pin and the base of the runner. Pro’s

• •

Low cost & easy to assemble Doesn’t require the hinge runner to be open (which could allow dirt & water into the main casing) Easier to replace than wires Only need to pass through one of the runners (top or bottom)

Con’s • •

•

Copper track will be open to the elements and may corrode over time The pin could easily come loose from the track meaning loss of power/data to the second screen Being able to access the track (which will have power running through it) is a safety risk

CONCLUSION Through this testing it was discovered that all the methods that required pressure to make the connection were unreliable, and therefore the best solution for the connectivity problem is to use wires that run through the hinge. The level of resistance (measured as brightness of the LED) through each material/option varied, with wire providing the least resistance, followed by copper track, then copper tape, and finally conductive elastomer (which barely lit the LED).

Wires/cable Method Running wires (housed within a cable) through the hinge from one screen to another; by leaving sufficient excess wire and empty space within the casing, the runner hinge should be able pull the wire along with it when the set up is altered. If necessary the thickness of the cabling can be reduced by spreading the wiring across two cables (one for the top hinge and one for the bottom). Pro’s •

Low cost

• •

No need for constant contact between the hinge pin and track Wires are a reliable way to transfer high amounts of data at high speed

Con’s • • •

•

Difficult to assemble Difficult to replace in the event of breakage Means that the runner hinge has to have an opening for the wire running along it (which may allow dust and water into the main casing) May need to make the hinge pin thicker

DEVELOPING THE ELECTRONICS The second area for development is the electronics, the main tablet circuitry will be outsourced from a supplier then the circuity needed to add the additional functions, such as the dual screen, will be specially manufactured and added to the outsource components. The aims for this area of development are to; •

Understand the circuitry of a traditional tablet and how it can be used within my product.

•

Create & test a circuit that senses and enables the set up’s and outputs as stated in specification point 1.1.3.

•

Write & test any code that may be needed in order to allow the outputs as stated in specification point 1.1.3.

•

Create a model that demonstrates how the electronic features of the product function.

These aims will be met using methods such as; research, modelling, reverse engineering, and testing.

GOALS

circuitry

Figure 1 : Arduino Mega Layout

Introduction To give the final product all the desired functionality, as per the specification, additional circuitry would need to be added to the outsourced tablet circuit. This additional circuitry would need to enable the following sequence; 1. Sense the set up of the product (open, closed, one screen behind the other, etc.) 2. Turn the device on, off, and leave it as it is, in accordance with the sensed set up. 3. Alter the output of the screens (turn on/ off, or alter the image) in line with the sensed set up. 4. Keep the device in the same set up until a new set up is sensed. Through research, modelling, and testing this report aims to create a solution that will enable this sequence of events.

Arduino

The use of an Arduino for development purposes was recommended by a lecturer at the University of Brighton due to the wide variety of components it will work with and its ease of use. Also, because the Arduino is open-source, and due to the general nature of programmes/hobbyists, there are a lot of free tutorials, circuit diagrams, and code available online that can be used to support the development process.

The Arduino is made up of two parts; a simple (physical) input/output board, and a (digital) development software that is used for programming. The board is a piece of hardware that you build your additional circuitry around, and the Arduino software (IDE) is an open-source computer programme that you write your code/sketch in before transferring it onto the Arduino board. There are currently 20 different types of Arduino board, the most widely used being the base modelled called the UNO. Because the circuit will need to support 2 screens (both of which have multiple inputs) plus a range of sensors it was decided that an Arduino Mega was more suitable than the UNO; this is because the Mega has 54 digital input/output pins opposed to the UNOâ&#x20AC;&#x2122;s 14 (Arduino. 2014). A diagram showing the layout of an Arduino Mega is shown in Figure 1.

Sensors One of the key functions of the circuitry is to sense the set up on the device. In the Ideation stage of this project it was decided that magnetic sensors, similar to those used to active the sleep/wake function in an iPad, would be used to sense the set up. Through research it was discover that these

Figure 2 : Hall Effect (Magnetic) Sensors magnetic sensors are formally known as Hall Effect sensors. Hall Effect sensors vary their output dependent on the magnetic field around them, there are commonly used for proximity switching, through combining the Hall sensor with specific circuity/ programme it can be used in a digital (on/ off) mode (Ramsden, 2006). This means that if the sensor is within a specified distance of a magnetic it will send a signal to the Arduino informing to to perform a certain task/output. Once it was decided that Hall Effect sensors were going to be used it was important to work out how many sensors would be needed and where they should be positioned within the product in order to sense each set up but not interfere with one another. It was calculated that 4 sensors would be needed, even though there are 5 different set upâ&#x20AC;&#x2122;s one involved the screens being pulled away from one another and therefore no sensor is needed; and that these 4 sensors would need to be positioned in rows (spaced evenly running vertically down the product) in order to keep them at a safe distance from one another and avoid interference. Figure 2 shows the positioning of the sensors.

Screens Due to financial restraints it was decided that two basic LCD screens would be used for the model, instead of full colour LCD screens which are significantly more expensive.

Figure 3 : Other Components

Figure 4 : Final Circuit Diagram A 16-pin HD44780 interface LCD was chosen due to the wide availability of opensource Arduino code and tutorials that were available for it.

Other Components

Through researching both Hall Effect and LCD Arduino circuits it was discovered that extra components would be needed to complete the circuit. These included; 10k resistors to act as a pull up for the Hall Effect sensors, 10k Potentiometers to act as contrast controls for the LCD screens, and a 9V battery/connector to power the circuit. Figure 3 shows all the components that are 1

needed to build the circuit.

Circuit Layout Two different open-source Arduino circuits, one for the sensors (Hobbytronics, 2013) and one for the screens (Crocboy, 2010), were combined to create a circuit that would replicate those of the final product. While researching the best way to connect the 2 screens to the Arduino is was discovered that it is possible to run two screens off of the same data and RS pins, then use different enabler pins for each screen to differentiate them (Flummer, 2010). Therefore cutting the number of output pins needed to 7 from 12.

The final circuit is shown in Figure 4.

References Arduino. (2014). Compare Boards. Available: http://arduino.cc/en/Products.Compare. Last accessed 1st May 2014. Banzi, M (2009). Getting Started with Arduino. 2nd ed. Sebastopol: Make:Books. Crocboy. (2010). Connecting an LCD to the Arduino. Available: http://www.instructables. c o m / i d / C o n n e c t i n g - a n - LC D - t o - t h e Arduino/. Last accessed 1st May 2014.

Flummer, T. (2010). 4 LCD displays on 1 Arduino. Available: http://www.hackmeister. dk/2010/08/4-lcd-displays-on-1-arduino/. Last accessed 1st May 2014. Hobbytronics. (2013). Arduino UNO Tutorial 11 - Hall Effect Switch. Available: http:// www.hobbytronics.co.uk/arduino-tutorial11hall-effect. Last accessed 1st May 2014. Ramsden, E (2006). Hall-effect sensors: theory and applications (2, illustrated ed.). Elsevier.

PROGRAMMING For the circuit to work in the desired was it needed to be supported by a ‘sketch’ (code), this sketch had to recognise the set up (Hall Effect Sensor) input and then react with the required screen output (text or power). To construct the sketch, basic open-source code for the specific Hall Effect sensor and LCD screens were downloaded, then by using other multiple input/output sketches as reference these two pieces of code were combined to create the final sketch.

All Code was written in the official Arduino software before being uploaded to the Arduino via USB. Any text written in the following format are notes (which the Arduino doesn’t not read) and therefore are not part of the code/sketch. /* EXAMPLE *\ //EXAMPLE Figure 1 show the open-source Hall Effect Sensor code (Hobbytronics, 2013), Figure 2 shows the open-source LCD code (Flummer, 2010), Figure 3 shows other piece of code that were used as reference, and Figure 4 shows how they were combined to create the final sketch.

References Flummer, T. (2010). 4 LCD displays on 1 Arduino. Available: http://www.hackmeister. dk/2010/08/4-lcd-displays-on-1-arduino/. Last accessed 1st May 2014.

/* Hall Effect Switch Turns on and off a light emitting diode(LED) connected to digital pin 13, when Hall Effect Sensor attached to pin 2 is triggered by a magnet Hall effect sensor used is the A1120EUA from Allegro Microsystems This example code is in the public domain. http://www.hobbytronics.co.uk/arduino-tutorial8-hall-effect */ // constants won’t change. They’re used here to set pin numbers: const int hallPin = 12; // the number of the hall effect sensor pin (change to correct sensore pin) const int ledPin = 13; // the number of the LED pin (change to LCD output/pin) // variables will change: int hallState = 0; // variable for reading the hall sensor status void setup() { // initialize the LED pin as an output: (change to LCD output) pinMode(ledPin, OUTPUT); // initialize the hall effect sensor pin as an input: pinMode(hallPin, INPUT); } void loop(){ // read the state of the hall effect sensor: hallState = digitalRead(hallPin); if (hallState == LOW) { // turn LED on: digitalWrite(ledPin, HIGH); } else { // turn LED off: (change to LCD output) digitalWrite(ledPin, LOW); }

Hobbytronics. (2013). Arduino UNO Tutorial 11 - Hall Effect Switch. Available: http:// www.hobbytronics.co.uk/arduino-tutorial11hall-effect. Last accessed 1st May 2014.

}

Figure 1 : Hall Effect Sensor Code (with notes in red) 53

// include the library code: #include <LiquidCrystal.h> // initialize the library with the numbers of the interface pins (only need 2 LCD outputs, all pins the same except no2 which in the enabler) LiquidCrystal lcd1(12, 5, 7, 8, 9, 10); LiquidCrystal lcd2(12, 4, 7, 8, 9, 10); LiquidCrystal lcd3(12, 3, 7, 8, 9, 10); LiquidCrystal lcd4(12, 2, 7, 8, 9, 10); void setup() { // set up the LCD’s number of rows and columns: (only need 2 LCD outputs) lcd1.begin(16, 2); lcd2.begin(16, 2); lcd3.begin(16, 2); lcd4.begin(16, 2); // Print a message to the LCD. (change text, need more than one text output per screen, output dependent on input) lcd1.print(“Disp1”); lcd2.print(“Disp2”); lcd3.print(“Disp3”); lcd4.print(“Disp4”); } void loop() { // set the cursor to column 0, line 1 // (note: line 1 is the second row, since counting begins with 0): lcd1.setCursor(0, 1); lcd2.setCursor(0, 1); lcd3.setCursor(0, 1); lcd4.setCursor(0, 1); // print the number of seconds since reset: lcd1.print(millis()/1); lcd2.print(millis()/10); lcd3.print(millis()/100); lcd4.print(millis()/1000); }

Figure 2 : Multiple LCD Code (with notes in red)

/*You can use multiple if and else. For example :*/ (use to read all sensors and react, will need 1 if and 4 else if to read all 5 set ups)

if (button <10) Serial.print(“< 10”); (change to sensors

and 2 text outputs, one for each LCD) else if (button < 100) Serial.print(“< 100”); else if (button < 400) Serial.print( “< 400”); else Serial. print(“ > 399 “); // Note 399 not 400

/*This example, from Arduino.cc shows you how to read an analog input on Pin 0, convert the values from analogRead() into voltage, and print it out to the serial monitor.*/ // the setup routine runs once when you press reset: void setup() { // initialize serial communication at 9600 bits per second: Serial.begin(9600); } // the loop routine runs over and over again forever: void loop() { (need to loop so the Arduino is constantly reading the sensors and adjusting the set up) // read the input on analog pin 0: int sensorValue = analogRead(A0); // Convert the analog reading (which goes from 0 - 1023) to a voltage (0 - 5V): float voltage = sensorValue * (5.0 / 1023.0); // print out the value you read: Serial.println(voltage); } Figure 3 : Othe referenced Code (with notes in red) 55

//Set sensor pin numbers:

State03 = digitalRead(Sensor03);

const int Sensor01 = 52;

State04 = digitalRead(Sensor04);

const int Sensor02 = 50; const int Sensor03 = 48;

// Sense if sensor/set up 01 is activated

const int Sensor04 = 46;

if (State01 == LOW) { // Setup 01 output LCD 01

// include the library code:

LCD01.print(“THIS IS”);

#include <LiquidCrystal.h>

// Setup 01 output LCD 02 LCD02.print(“ONE DISPLAY”);

//Set LED pin numbers: LiquidCrystal LCD01 (12, 5, 7, 8, 9, 10);

// Sense if sensor/set up 02 is activated

LiquidCrystal LCD02 (12, 4, 7, 8, 9, 10);

else if (State02 == LOW) { // Setup 02 output LCD 01

// variables will change:

LCD01.print(“OFF”);

int Sensor01 = 0; // variable for reading the

// Setup 02 output LCD 02

sensor status

LCD02.print(“OFF”);

int Sensor02 = 0; // variable for reading the sensor status

// Sense if sensor/set up 03 is activated

int Sensor03 = 0; // variable for reading the

else if (State03 == LOW) {

sensor status

// Setup 03 output LCD 01

int Sensor04 = 0; // variable for reading the

LCD01.print(“FULL SCREEN”);

sensor status

// Setup 03 output LCD 02 LCD02.print(“HALF SCREEN”);

void setup() { // set up the LCD’s number of rows and

// Sense if sensor/set up 04 is activated

columns:

else if (State04 == LOW) {

LCD01.begin(16, 2);

// Setup 04 output LCD 01

LCD02.begin(16, 2);

LCD01.print(“FULL SCREEN”); // Setup 04 output LCD 02

// set the hall effect sensor pins as an

LCD02.print(“OFF”);

inputs: pinMode(Sensor01, INPUT);

// Sense if no sensor/set up 05 is activated

pinMode(Sensor02, INPUT);

else {

pinMode(Sensor03, INPUT);

// Setup 05 output LCD 01

pinMode(Sensor04, INPUT);

LCD01.print(“PAGE 01”);

}

// Setup 05 output LCD 02 LCD02.print(“PAGE 02”)

void loop(){ // Set to read the state of the sensors:

} }

State01 = digitalRead(Sensor01); State02 = digitalRead(Sensor02); Figure 4 : Final Code

4. MODELLING

Using the previously created circuit diagram and programming sketch (see 2. Circuitry & 3. Programming) a test circuit was created, this test circuit was housed within a 3d printed casing ,that loosely replicates the final product, to create a proof of principle model.

•

The hinge mechanism

•

Wire cut outs to allow the Arduino to be attached to the circuit outside of the case.

•

Cut outs for the sensors and magnetics (positioned as per 2. Circuitry - Figure 2)

•

Space for all other circuitry.

A 3D model of the casing was created within Solidwork’s, this model included;

•

A cut out and securings for the screens

•

Securings for a clear Acrylic backing (so that circuity can be viewed when in the case)

From this 3D model a Makerbot was used to print out all of the components before laser cutting the back plates and assembling them into the model.

The image shows the electronic proof of concept model, although the model did not work (due to a component or soldering failure) a lot was learnt from it. Including the following points;

•

Thinner cable/wire will need to be sourced for the final product

•

A wire runner system would be useful to ensure a smooth set up change

1•

The specific Hall Switch Sensors used

are slightly too sensitive (less sensitive ones can be sources) •

From reviewing the circuit with a more experience Arduino user it was deemed that the concept should work.

If there had been more time available the concept would have been remodelled using simplier LED’s as the output instead of the more complex LCD screens that require 10 connections each.

REVERSE ENGINEERING To gain an insight into the internal works of a tablet device, a device was purchased for disassembly and review. •

The following discoveries were made;

•

The touch screen is made of two components, a visual display and a touch sensitive panel

•

The internal PCB is 110mm x 68mm x 7mm

•

The battery is 95mm x 70mm x 3mm

•

The case is held together using push fits

•

The PCB is held in place with 3 screws (these are the only screws in the product)

The internal from this tablet will be used in the final prototype.

HUMAN FACTORS

1. GOALS

Once the mechanism and electronics of the product had been finalised Human Factors development could take place; this will focus on the desirability and usability of both the physical product and the digital interface. The form/aesthetics brought forwards from the ideation stage will be used as a starting point. The aims for this area of development are to; •

Understand the process of using each of the key functions/features of the product, and develop the product based on the findings.

•

Develop the design of the physical product & digital interface based on Patrick Jordan’s ‘Four Pleasures’. and specification point ‘1.6.5. Interface.’

•

Create an ergonomic product that is comfortable to use, in line with specification point ‘1.6. Ergonomics’ and ‘1.4. Environment’.

•

Test the key features of the product and develop it based on the findings.

These aims will be met using methods such as; research, mood-boards, sketching, modelling, case studies, and testing.

TASK analysis Introduction

In order to understand users interaction in each of the key uses Task Analysis will be used. Through carrying out Task Analysis’, in which larger tasks are broken down into small tasks and arranged as a flow chart, it will be possible to identify the key user interactions with the product. By reviewing each user interaction and the Task Analysis as a whole it will be possible to identify; • • •

Areas that could be simplified (broken down into less tasks) Tasks that need further consideration (how is that going to be possible) Tasks that affect the design of the casing or interface (need buttons, etc)

A total of 4 Task Analysis’ will be completed, focusing on the fundamental features of the product.

Figure 1 : Task Analysis - Initial Set Up of the Device

Figure 2 : Task Analysis - Changing the Devices Set Up

Figure 3 : Task Analysis - Using Devices for Group Work

Conclusion From carrying out Task Analysis the following concerns/areas for development were identified;

Charging • • •

Where should the charging point be located How is the charging port marked/ labelled How is the user informed that the device is fully charged

Buttons • • • •

Where should the following ‘buttons’ be located; Share a file Change the display Power on/off

Figure 4 : Task Analysis - Sharing Files

Initial Set Up of the Device • •

How can this be made simpler What should the images/illustrations look like

Changing the Set Up •

• • •

How does the user hold the product, is it easy to change the set up of the device from this point Is the process of changing the devices set up intuitive How does the user discover each set up How does the device click into the set up (how strong is the hold Vs how easy is to re-change the set up once clicked in place)

Working as a Group • •

• •

What happens if there is an odd number of devices (that can’t form a rectangle) What if the users would like to change the master device half way through a session What if the devices accidentally jogged out of place (do they disconnect) How does the device recognise what other devices are tiled to it and whether it should return to an existing group study session (is this possible) How are the files transferred (bluetooth/ wifi?) How easy is it to drag file from one device to another (how far does the file have to be dragged Vs what is the users reach)

Many of these area’s will be further explored throughout the Human Factors section of development. 71

ergonomics & user TESTING Using the areas of concern/development that were discovered in the Task Analysis as a base, the following list of goals (for both the interface & casing/product) for research & user testing were established;

For the user to be able to drag a file icon to the edge of the screen, with a 90%+ success rate.

Casing/Product Goals Interface Goals 1.

All buttons on the interface should be easily accessible when the user is holding the product (in each set up). 2.

The initial set up of the device to take under 3minutes.

The user to be able to change the display view on the product in under 15 seconds.

For a group of users (of both odd or even group numbers) to be able to tile their devices together without loosing any of the displayed image.

For group users to be able to change the master device at any point in a study session.

Each goal will be researched, tested, and developed in order to be met. The list below shows the priority of the goals.

Priority 1.

Casing Goal 2

Casing Goal 3

Interface Goal 1

Interface Goal 3

Casing Goal 4

Interface Goal 2

Interface Goal 6

Casing Goal 5

For the product to click into each set up in a way that is/feels secure, but does not affect the set up change time.

Casing Goal 1

For tiled devices to be able to with stand small â&#x20AC;&#x2DC;jogsâ&#x20AC;&#x2122;/levels of vibration without disconnecting from one another.

11. Interface Goal 5

The user be able to charge the device straight out the box without looking at any instructions.

The user to be able to easily change the set up of the product from a natural hold position, without moving the location of there hands more than once.

The user to be able to discover/change the product into the intended set ups without looking at any instruction in under 15 seconds per set up.

10. Interface Goal 4

Figure 1 : Different Size Options

3.1 PREVIOUS user TESTING

Basic user testing was previously carried out in the ideation stage. This user testing included;

•

Testing different size models (each with a different scaled interface) to see what size users preferred and were able to read from.

Testing different form models to see what the users preferred in teams of

appearance and comfort.

•

Testing the hinge mechanism to ensure its basic function

The findings and developments from these previous tests will be used as a base for Human Factors development.

2 males & 2 females with

handspans between 175 - 225mm located

3.2

in A cafe &

on a train

Initial user TESTING

Figure 1 : Who & Where?

What?

Environment?

Scenario?

How the users hold the product and the optimum position for the buttons on both the physical device and the interface, for each set up.

All testing will be performed in a classroom environment set up to simulate the three following environments;

The following scenario will be tested for each set up and environment (with paper over the screen of the model);

Seated with a limited amount of space and no surfaces available to rest the device on (set up to simulate being on a train with someone sat next to the you)

1. 2.

How? By asking the user to hold the product in each position and then using ink or paint to mark their finger/thumb reach while they are holding the device.

Measurements? The results will be measured using photographs/observations, and the area on each of the screens that all the participants could reach (for each set up).

Who? 4 participants aged between 16- 25 (the main target audience of the device), a mix of male and female with a range of hand spans (which will be measured before testing).

& 4. Seated in front of small surface that can be used to rest the device on, this surface will be a similar size to a cafe bistro table and have a drink and plate on it (which the user can alter the positioning of). All these environments will be created in dim light settings with mid levels of noise in order to replicate worse case environment. Ideally, the effect of small amounts of vibration on reach and accuracy would have also been tested, but the facilities to test this are not available.

The user decides to use the device They pick up the closed device from a surface They then put the device into the desired set up (the participant will be shown what set up to use) Once the product has been set up they are ready to use the device (at this point finger paint will be put onto the participants thumbs/fingers) The user then proceeds to use the device (at this point the participant will be asked to mark the areas that they can easily reach with their thumb/fingers on each screen) The user then packs away the device (the paper, which will have wet paint on it will be removed beforehand)

After each test the user will be able to wash their hands before repeating the test for the next set up/environment. For more information and evidence on this user test please see appendix 2.

one screen half behind the other

single screen

participants could reach the whole of the half screen & the bottom centre of the full screen without repositioning their hands

participants could reach across the middle of the screen on both sides in a ‘sweep’ form

dual screen (book style)

sides

participants could reach across the middle outer vertical edges of the screens in a ‘sweep’ form

participants could reach the top of the device as shown

Figure 2 : Test Results

4 males & 1 females located

3.3

in A cafe &

on a train

MECHANISM user TESTING

Figure 1 : Who & Where?

What?

Environment?

Scenario?

The intuitiveness and ease of the initial set up changes/hinge mechanism.

All testing will be performed in a classroom environment set up to simulate the three following environments;

The following scenario will be tested; 1.

How? The intuitiveness of the hinge will be tested by initially asking the user to move the device into as many set ups as they think it has (without showing them the set up flash cards beforehand) then asking them to move the device into a set up shown to them on the flash cards.

Measurements? The results will be measured as how many correct/in-order set up the user discovered on their own and how long it took the user to change the devices set up when shown the flash cards. After the test each participant will also be asked their opinions on the mechanism.

Who? 5 participants aged between 16- 25 (the main target audience of the device), a mix of male and female.

Seated with a limited amount of space and no surfaces available to rest the device on (set up to simulate being on a train with someone sat next to the you)

& 3. Seated in front of small surface that can be used to rest the device on, this surface will be a similar size to a cafe bistro table and have a drink and plate on it (which the user can alter the positioning of). All these environments will created in dim light settings with mid levels of noise in order to replicate worse case environment. Ideally, the effect of small amounts of vibration on reach and accuracy would have also been tested, but the facilities to test this are not available.

The user picks up and has 30 seconds to look over/become familiar with the device They then have 60 seconds to discover the set ups (the participant is asked to set up the device into as many possible set ups, one after the other, identifying when they think they have found a new set up) The device is then put back into the closed/storage set up. Then

The user puts the device into the desired set up (a flash card will be shown to the participant stating what set up to use, the user will not be shown how to put the device into the set up) The user then closed the device and puts it away.

For more information and evidence on this user test please see appendix 3.

RESULTS -

participants

average

1.8

13.2

FOUND (NO.)

TIME (SEC.)

key findings -

the Most common reason for the participant not finding the set ups was because they bent the device back on itself (which does not lead to a set up)

The single hinge at the top caused the screens to pull appart meaning they didnâ&#x20AC;&#x2122;t guide the screens very well. This also caused confusion in some of the participants

Figure 2 : Test Results

The magnets acted as confirmation of and guidence to each of the set ups. Making the magnets stonger may help the user find the set upâ&#x20AC;&#x2122;s easier

3 males & 2 females located

in A cafe &

on a train

Figure 1 : Who & Where? What?

Environment?

Scenario?

The intuitiveness and ease of the developed hinge mechanism, that includes stoppers to avoid over movement in the hinge.

All testing will be performed in a classroom environment set up to simulate the three following environments;

The following scenario will be tested;

How?

Seated with a limited amount of space and no surfaces available to rest the device on (set up to simulate being on a train with someone sat next to the you)

The intuitiveness of the hinge will be tested by initially asking the user to move the device into as many set ups as they think it has (without showing them the set up flash cards beforehand) then asking them to move the device into a set up shown to them on the flash cards.

Measurements? TThe results will be measured as how many correct/in-order set up the user discovered on their own and how long it took the user to change the devices set up when shown the flash cards. After the test each participant will also be asked their opinions on the mechanism.

Who? 5 participants aged between 16- 25 (the main target audience of the device), a mix of male and female, the participant will not be the same to those used in the first set of testing (the product will be completely new to them). 79

The scenarios will be as per the previous hinge test to ensure consistency. For more information and evidence on this user test please see appendix 4.

RESULTS -

participants

average

3.8

6.6

FOUND (NO.)

TIME (SEC.)

key findings -

the stoppers made a very large difference with all but one of the participants finding all the set up’s in the allocated time

There is some vertical movement in the hinge that make the set up changes slightly less smooth. tolerences will need to be worked on to resolve this

Figure 2 : Test Results

‘open - screens pushed together’ set up was the only set up to no be found. this likely happened because of the distance between the screens

3 males & 2 females IN A

CLASSROOM

WITH 3 DIFFERENT STRENGTHS OF MAGNET

2mm

12mm

2mm

12mm Magnet strength C8

3mm

10mm Magnet strength N35 Neodymium

Magnet strength N52 Neodymium

Figure 1 : Who, Where & What? What?

Who?

Scenario?

How secure the product is/feels when it is clicked into place for each set up and that this does not affect the users ability to change the products set up.

5 participants aged between 16- 25 (the main target audience of the device), a mix of male and female.

The following scenario will be tested;

How? The feel of the ‘click’ and how this affects users ability to change the product set up will be tested by asking the user to open and change the set up of various models (each using different strength magnets), the ability for each magnet to hold the device in position will be tested by asking the user to hold the product in it’s set up once in place using only one hand.

Measurements? The results will be measured by asking the users to fill out two scaled (1-5) questions on each magnet (one for feel and another on it’s ability to hold the device in place) rating it from ‘1 - Extremely too strong’ to ‘ 5 Extremely too weak’ and ‘1 - Extremely Easy’ to ‘ 5 - Impossible’. An average result for each magnet and set up will then checked from the results.

Environment? 2. All testing will be performed in a classroom environment set up to simulate the following worst case environment; Seated with a limited amount of space and limited surfaces available to rest the device on. In dim light settings with mid levels of noise. Ideally, the effect of small amounts of vibration on reach and accuracy would have also been tested, but the facilities to test this are not available. As per the previous hinge test to ensure consistency.

3. 4.

5. 6. 7.

The user picks up and has 30 seconds to look over/become familiar with the device They then have 60 seconds to discover the set ups They then close the device From close the user puts the device into the desired set up (a flash card will be shown to the participant stating what set up to use) The user then holds the product with one hand in its set up for 15 seconds The previous 2 steps are repeated until all the set ups have been tested After the final set up the user closes the device.

After each test the magnets within the model will be changed and the scenario will be repeated.

For more information and evidence on this user test please see appendix 5.

Pull Apart = Magnet strength C8

SLIdE Apart = Magnet strength N35 Neodymium

Figure 2 : Test Results

3.4 FORM user TESTING

What? How comfortable the form feels in the users hands while in the single & dual screen set ups.

How?

- How comfortable was the model to hold? (rated from ‘Really Uncomfortable -1’ to ‘Really Comfortable - 5’ for each of the form models in each of the tested set ups.

Asking the user to hold a range of models (one for each of the forms) in both the single and dual screen set ups before gaining feedback on their thoughts on each design/form.

- How much do you like the design? (rated from ‘Ugly -1’ to ‘Beautiful – 5’ for each of the designs, the models will be supported by illustrations showing the finish of each product)

Measurements?

The results for each questions will be averaged.

After the test each participant will be asked to rate the following questions;

Who?

Figure 1 : Proposed Forms (1 -3, Left to Right)

How comfortable was the mode to hold when in dual screen mode?

Really uncomfortable

How comfortable was the mode to hold when in single screen mode?

Really uncomfortable

what is your opinion on the look of the design?

ugly

5 participants aged between 16- 25 (the main target audience of the device), a mix of male and female.

Environment?

pulled apart , mode (the model is handed to the participant in this set up) 2.

The users uses the device to read (the participant is asked to hold the model as they would it they were going to read a book)

The participants opinions on the form/ model when in the dual screen mode are recorded (any verbal feedback is noted)

The users decide to use the device in the single screen, one screen behind the other, mode (the model is handed to the participant in this set up)

All testing will be performed in a classroom environment, seated at a desk.

Scenario? The following scenario will be tested for each model; 1.

The users decide to use the device in the dual screen, one screen next to the other

The users uses the touch screen of the device (the participant is asked to hold the model as they would it they were going to use itâ&#x20AC;&#x2122;s touch screen to carry out a task such as browsing the internet)

The participants opinions on the form/ model when in the single screen mode are recorded (any verbal feedback is noted)

The user assesses the aesthetic of the design (the participant is shown both the model and an illustration to rate)

2 3 1 3

1 2 1

Figure 2 : Average Results

Really comfortable

beautiful

3.5 INTERFACE user TESTING

What?

3 males & 2 females IN A

CLASSROOM

USING PAPER

The time it takes to run through the initial set up of the device (should be under 3 minutes), and how easy it is.

How? Asking the user to run through the set up process (on flash cards), using the think aloud method.

DUAL SCREEN

Measurements? The results will be measured as how long it took the user to run through the process and how many errors they made in this time. After the test each participant will also be asked to rate a series of questions on the ease of the task from ‘Strongly Agree’ to ‘Strongly Disagree’. Any comments made will be noted and considered in development.

SCREEN 01 (WEB PAGE, BOOK, APP, ETC)

SCREEN 02 (DIFFERENT WEB PAGE, BOOK, APP, ETC)

Who? 5 participants aged between 16- 25 (the main target audience of the device), a mix of male and female.

SINGLE LARGE DISPLAY

Environment? All testing will be performed in a classroom environment, using flash cards that are the same size as the device screens.

E DISPLAY D SINGLE BO (IMAGE OVER BOTH SCREENS)

Scenario? The following scenario will be tested; 1.

The user will run through the set up process on flash cards (no hints will be given as the interface should be intuitive).

For more information and evidence on this user test please see appendix 7.

Figure 1 : Who, Where & What?

RESULTS -

participants

average

107

0.8

TIME TAKEN (SECS)

ERRORS (NO.)

key findings -

the participants were confused by the different set ups shown to them and how they were different from one another

the participants felt that there was a lot to do in one go. with one participant stating â&#x20AC;&#x2DC;another one?!?â&#x20AC;&#x2122;

Figure 2 : Test Results

the participants felt that the images demonstrating each display option were not very clear as there was too much text on them

What? The ease of changing the display view when the device is already in its set up, which should take under 15 seconds.

How? Asking the user to run through the display change process (on flash cards), using the think aloud method.

Measurements? The results will be measured as how long it took the user to run through the process and how many errors that they made Any comments made, due to the think aloud method, will be noted and considered in development.

Scenario?

Who?

The following scenario will be tested;

5 participants aged between 16- 25 (the main target audience of the device), a mix of male and female.

Environment? All testing will be performed in a classroom environment, using flash cards that are the same size as the device screens.

The user will decide on a display view (a flash card will be shown to the participant stating what display type to use) They will then run through the display change process on flash cards (no hints will be given as the interface should be intuitive).

3 males & 2 females IN A

CLASSROOM For more information and evidence on this user test please see appendix 8.

Figure 1 : Who, Where & What?

RESULTS -

participants

average

0.8

TIME TAKEN (SECS)

ERRORS (NO.)

key findings -

the participants struggled in finding the option to change the display (2 users got it straight away, the other 3 took a while) The likely reason for the split is that apple users are used to ‘swipe up for options’ whereas android users are used to ‘go to the top bar for options’

The ‘would you like to make this display option your preference’ sequence added a lot of time onto the task. one participant made a mistake at this point.

Figure 2 : Test Results

The participants felt that the images demonstrating each display option were not very clear as there was too much text on them. They also did not understand why the current display setting was offered as an option (as it wasn’t a change).

What? How well the interface works when being used in group work mode.

How? Asking the users to run through each process (on multiple flash cards), using the think aloud method and group discussion.

Measurements?

AM I THE MASTER DEVICE?

Who?

YES

The results will be measured as how long it took the user to run through the process and how many errors that they made Any comments made, due to the think aloud method, will be noted and considered in development.

4 participants aged between 16- 25 (the main target audience of the device), a mix of male and female, working together as a group.

Environment? All testing will be performed in a classroom environment, seated around a large table, using flash cards that are the same size as the device screens.

Scenario? The following scenario will be tested; 1.

The users decide to take part in a group study session (the participants are sat around the table and given a model each) The users tiled there devices together (a flash card will show the participants what the group work set up should look like) The device recognises that the devices are tiled together (the first screen/flash card is put onto each device) The users set up the group task mode (running through the process on flash cards) The users exit the group work mode.

AM I THE MASTER DEVICE?

No hints will be given as the interface should be intuitive.

For more information and evidence on this user test please see appendix 9.

YES

RESULTS -

participants

53 TIME TAKEN (SECS)

YES AM I THE MASTER DEVICE?

ERRORS (NO.)

key findings -

the participants asked about changing the master device

AM I THE MASTER DEVICE?

YES

the participants wondered what happens if two people press ‘yes’ to be the user device at the same time

the participants ask about what would happen if just one person wanted to leave the session Figure 1 : Test Results

desirability

The ‘Product Benefit Specification’ (below) focuses on the benefits for each pleasure, why they are important, and how they can be met (Jordon, 2002).

Physio

Psycho

Socio

Product benefit 01 : The product should feel nice in the users hands.

Product benefit 04 : The product should be easy to use straight out of the box.

Product benefit 07 : The product should allow the user to express themselves.

Why : The product is likely to be held in the hands when being used.

Why : Students are very busy and therefore do not have much time to learn to use a new tool before it’s of benefit to them.

Why : Social identity is very important to teenagers & young adults, therefore the product should allow them to express themselves (this is specifically important as the product is likely to be used in a group setting).

How : Applying texture to the areas of high contact (back & vertical edges) and adjusting the form of the product so that it sits comfortably in the users hands.

Product benefit 02 : The buttons should be satisfying to press. Why: The user will have to use the buttons on the casing at least twice per use (to switch on and off). How : Locating the buttons in an easily accessible location, applying a contrasting texture to the buttons and using buttons that are of a good size, spacing and ‘click’ (feel & sound) nicely.

Product benefit 03: The set up closures/holds should feel secure. Why : Every time the users uses the product they will have to move it into a set up, the user need to be confident that this set up will hold in place. How : Using a closure that guides the user then clicks into place (feel & sound), and requires the right level/balance of force (feel secure but is not too high) to reverse.

The ‘Four Pleasures’ framework is going to be used to develop the design of the product into something that is more desirable and emotionally durable, the ‘Four Pleasures’ consist of; physio-pleasure, socio-pleasure, psycho-pleasure, and ideo-pleasure. For this product the following pleasures are going to be focused on; physio (pleasure from senses such as touch, sound & smell), psycho (pleasure from carrying out or completing a task), and socio (pleasure from social interaction or representation).

How : Creating an intuitive interface and a mechanism that guides/leads the user into each set up, clearly marking all the buttons/ ports so the user does not have to learn where they are (or read a manual to find them).

How : Making the product & interface customisable or available in a wide range of styles.

Product benefit 05 : The process of changing the set up of the product should be quick.

Product benefit 08 : The product should encourage positive social interaction.

Why : Students often have to work to tight deadlines and therefore a product that requires minimal input in order to make a task easier is of importance to them.

Why : Students are already a social bunch, research showed that they often share work/ findings among one another, and therefore the product should enable this (ideally making it easier).

How : Developing the interface & hinge to ensure that set up change of the product can take place in under 15 seconds.

How : Creating an interface that allows users to share files (both remotely and in person) and offers group work modes that are fun and enhance the users learning experience.

Product benefit 06 : The product should make the task of studying more pleasurable. Why : For most students studying is not an enjoyable task therefore if the product improves this experience it will be more emotionally durable. How : Making the products aesthetics & interface similar to ‘fun’ gadgets rather than study tools/books.

Product benefit 09 : The product should be something that the user is proud to own. Why : The product is likely to be used in public locations and therefore needs to be something that they are happy to be seen with, being proud of the product will also mean the user will want to show it off (encouraging the user to use the product more, and therefore study more). How : Making the product identifiable as something that is new, different and trendy, rather than just another tablet.

AIM : To Feel good in the users hands

AIM : TO Create/use satisfying buttons METHOD : HF researcH & TESTING

AIM : TO allow self expression

4 AIM : TO make studying pleasurable METHOD : moodboards & feedback

AIM : TO have a secure feeling closure METHOD : user testing

Each of the points within the â&#x20AC;&#x2DC;Product Benefit Specificationâ&#x20AC;&#x2122; will researched into before the product is developed and tested to ensure that it meets the benefit. If the product does not meet the benefit further research and development may need to take place. Initially development will be focused on the casing, then once this has been finalised focus will shift to the interface (which will work alongside the physical product, complimenting one another). Figure 1 shows the target benefits for the casing and the methods that will be used to ensure they are met. References Jordan, P.W. (2002). Designing Pleasurable Products: An Introduction to the New Human Factors. CRC Press

Figure 1 : Aims

METHOD : user testing

AIM : TO HAVE quick & easy set up changes

METHOD : research & user testing

METHOD : moodboards & observations

AIM : TO BE easy to use straight away

METHOD : HF researcH & MODELLING

4.1 CASING AIMS

Gloss finish nice finish but marks easily & feels sticky

Aim 01 To create a product that feels nice in the users hands.

Texture Even though the materials have already been selected it is still possible to adjust the finish of the material to improve the way it feels when in the users hands. The first decision to be made was whether to use a gloss/smooth finish or a matt/textured, samples for both materials were examined at it was decided that a matt/ textured finish would be more suitable for the areas of high contact. This was due to the fact it offered better grip, also the gloss finish felt sticky in the hand and ended up covered in finger prints after being picked up. After the decision to use a matt/textured finished was made it was important to establish the level of texture that should be applied. Samples of the following three texture levels were examined; low level texture (spray finish), mid level texture (in-mold spark), and high level texture (in-mold texture). It was decided that the preferred level of texture was low level, this was because it felt soft in the hands and was not as overpowering, in both feel & appearance, as the other two option. Figure 1 shows each of the finishes and their proâ&#x20AC;&#x2122;s and conâ&#x20AC;&#x2122;s.

MATT finish more tactile & offers good grip

LOW LEVEL TEXTURE FEELS SOFT & looks nice

MID LEVEL TEXTURE feels nice & tactile but looks unfinished

Form By using anthropometric data (see product specification point 1.6) along side information gained through user testing as an influence, a basic form that feels nice to hold, and could be worked around, was created. Figure 2 shows this form and its key features/ restrictions.

high LEVEL TEXTURE interesting look but too corse/rough

Figure 1 : Texture 93

Figure 2 : Form oc ts

ratio

siz

was most popular in user testing

125mm closed width was most popular in user testing

max 10mm

meaning a 50 percentile women can reach 50mm into the screen

inline with main competitor

max 16mm closed width

for more comfortable grip

175mm height

screen g

iew

1.4

fo re

to allow for a 50 percentile mans hands to grip without interference

bottom 100mm of casing must be clear

curved vertical edges

Aim 02

VOLUME BUTTONS

LOCATED ON THE RIGHT HAND SIDE OF THE CASING

To ensure that all buttons are satisfying to press.

TILTED ENDS TO INFORM THE USER OF WHETHER IT’S THE UP OR DOWN BUTTON

The optimal position for the buttons (shown in Figure 3) was discovered through user testing (see section ‘3.2. Initial User Testing’ for the test report), this position is within easy reach when the user is holding the product in each of the set ups and therefore should be used for key buttons/interactions.

3 MM

Positioning

>13 MM BETWEEN THE PUSH POINTS OF THE BUTTONS

As per specification point ‘1.6.1.2. Buttons’, all buttons should have a diameter of between 8 – 25mm, a displacement of between 2.8 – 11mm, and a separation (from other buttons) of 13 – 50mm (Pheasant, S. 1987). The power button, which if accidentally pressed could cause distress to the user (in terms of lost work and time), should be spaced at a safe distance from the other buttons.

8 MM

Size & Separation

MATT & TEXTURED + & - SYMBOLS

GLOSS TEXTURE TO CONTRAST THE REST OF THE CASE

Force Required As per specification point ‘1.6.3.1. Buttons’, all buttons on the product should require a force of between 2 – 6 Newtons to be activated (Pheasant, S. 1987).

POWER BUTTON

LOCATED ON THE TOP OF THE CASING (AWAY FROM THE OTHER BUTTONS)

Feel & Form The feel/form of the buttons is important because they can inform the user of what the buttons function is and whether it has been pressed. Form should be used in order to make the buttons more identifiable (therefore improving usability), this form should differ dependent on its function. Other methods used to make the buttons more identifiable include applying texture to their surfaces (this texture should differ from that of the rest of the casing in order to inform the user that they are touching the button) and altering the way that the button reacts when being pressed by applying a ‘click’ sound and/or feel.

1mm meaning the user is less likely to accidently press it 8mm

Round form that replicates that of a power symbol DEBOSSED POWER SYMBOL Figure 3 : Buttons

Aim 03 To have a closure the feels secure and can be trusted.

2mm

Testing) took into consideration the feel of the magnets; how they clicked in and out of place and how this make the product feel (secure or flimsy), Figure 4 shows the users preferred magnet size & strength.

Force Required (Ergonomics) As per specification point ‘1.6.3.2. Set Up Changing’ changing the set up of the device should require no more than 22N, the suitable focus for light wrist & finger operation (Pheasant, S. 1987).

Feel 95

1User testing (see 3.3. Mechanism User

12mm Magnet strength N35 Neodymium Figure 4 : Closure

Aim 04 & 05 For the set up change process to be quick and easier to do straight out of the box.

MOVEMENT BEFORE

MOVEMENT AFTER

NO STOPPER

WITH STOPPERs

Force Required (Ergonomics) Using the right level of friction in the hinge, not too high so it’s hard to change and not so low that it’s over sensitive, is very important. By modelling hinges (see Mechanism point 2.) and using them for user testing (see Human Factors point 3.3.) it was possible to design a hinge that used a good level of fiction. This hinge also allowed the mechanism to be operated using less that 22N (as per specification point ‘1.6.3.2. Set Up Changing’).

Intuitiveness

There were no visual guides/indicators on the product that informed the user of function

•

The hinge mechanism allowed over movement meaning the user could put the product into unintended set ups

•

The magnetics on the product didn’t snap/pull the product into each set up (confirming the set up to the user)

Therefore the mechanism was developed to include stopper bars, these bars both stop the product from moving into unintended set ups (along the front of the screen and far end), physically guide the product into each set up and act as a visual guide for the user (see Figure 5). The strength of the magnets also influenced the intuitiveness of the product, the magnets that were chosen gently pull the product into each set up, confirming it to the user, for more details on the magnets/closure see Aim 03. These changes significantly reduced the amount of time it took the user to change the product into each set up and the number of errors (if any) that they made while doing so.

References Pheasant, S (1987). Ergonomics Standards & Guidelines for Designers. Milton Keynes: British Standards Institution.

Figure 5 : Hinge/Mechanism

STOPPER

•

RAISED BAR THAT THE HINGE CANNOT GO OVER

Initial modelling (see Mechanism point 2.) & user testing (see Human Factors point 3.3.) also established that the original mechanism brought forward from ideation was not very intuitive. This was because;

Aim 06 For the product to make studying more enjoyable.

Function The main function of the product already fulfils this aim; the use of technology to make the task of studying easier and more interactive.

Aesthetics By creating a mood board (see Figure 6) as inspiration and designing around it, a finished product that resembles fun and trendy gadgets such as headphones or speakers rather than study tools such as books or folders, can be created. For the full moodboard please scan the QR code in the top right corner of the moodboard.

Aim 07 For the product to allow the user to express there social identity.

Aesthetics/Customisability Initial research showed that social identity was very important to the products target market, therefore a customisable productive bumper was added to the device during the ideation stage. This bumper can easily be changed throughout the lifespan of the product to suit the users style (which is likely to change over the lifespan), the initial product will be packaged with a selection of plain block colour bumpers, and additional (more styled) bumpers will be available as a stand alone product.

Stereotypes/Trends In order to create a range of bumpers that would appeal the maximum number of people it is important to understand the main stereotypes/trends that fall within my target market therefore, using discoveries from the research phase as influence, mood boards were created. These mood boards cover a range of different stereotypes/trends and can used as inspiration when designing the bumpers. For the full moodboard please scan the QR code in the top right corner of the moodboard. 97

Figure 7 : Stereotype/Trends Mood-Board

Figure 6 : Fun Mood-Board

MOOD BOARD

4.2 CASING CONCEPTS

CONCEPT 01

CONCEPT 02

CONCEPT 03

AIM 01 : To create a product that feels nice in the users hands.

AIM 01 : To create a product that feels nice in the users hands

The form of this design is inline with the ergonomic guidelines, the back of the casings curve to make the product comfortable to hold, and the cover that fits over the side and back of the device has a low level matt texture.

The form of this design is inline with the ergonomic guidelines, the edges of the casings are curved to make the product more comfortable to hold, and the whole main casing has a low level matt texture applied over it.

The form of this design is inline with the ergonomic guidelines, the outside back edges of each the casings are curved to make the product more comfortable to hold (in both set ups), and the slip in customisable back plates have a low level matt texture finish.

AIM 02 : To ensure that all buttons are satisfying to press.

The buttons in this design are inline with the ergonomic guidelines & the intuitiveness redesign. The volume buttons are located on the right-hand side, as the user had more reach of this side, and the power button is out of the way on the left-hand side (as to avoid being accidentally pressed).

AIM 03 : To have a closure the feels secure and can be trusted.

The magnetic closure in this design is inline with the user testing results.

AIM 04 & 05 : For the set up change process to be quick and easier to do straight out of the box.

The redesigned hinge with guides and stoppers is built into the top removable plate on the top edges of the design.

The redesigned hinge with guides and stoppers is build into the casing of this design.

AIM 02 : To ensure that all buttons are satisfying to press. The buttons in this design are inline with the ergonomic guidelines & the intuitiveness redesign. The volume buttons are located on the right-hand side, as the user had more reach on this side, and the power button is out of the way on the left-hand side (as to avoid being accidentally pressed). AIM 03 : To have a closure the feels secure and can be trusted. The magnetic closure in this design is inline with the user testing results. AIM 04 & 05 : For the set up change process to be quick and easier to do straight out of the box. The redesigned hinge with guides and stoppers has been built into the silicone cover. AIM 06 : For the product to make studying more enjoyable. This design took inspiration from the bright colours, curved edges, and quirky prints/ texture in the mood-board to create something that replicated a fun gadget rather than a study tool. AIM 07 : For the product to allow the user to express there social identity. This design has a customisable silicone cover, this cover stretches over the back and sides of the device and can easily be changed by the user.

AIM 06 : For the product to make studying more enjoyable. This design took inspiration from the flashes of bright colour and rounded form (edges) in the mood-board to create something that replicated a fun gadget rather than a study tool. AIM 07 : For the product to allow the user to express there social identity. This design has customisable PC/ABS top & bottom plates that sit slightly above the top of the main casing, these plates add a flash of colour to the design.

AIM 06 : For the product to make studying more enjoyable. This design took inspiration from the bright colours, curved edges, and contrasting forms in the mood-board to create something that replicates a fun gadget. AIM 07 : For the product to allow the user to express there social identity. This design has a customisable plate (which could be available in a variety of materials) this plate slips into the main casing (covering the outer edge and back of the device) and can easily be changed by the user.

Figure 1 : Concept 01

101

Figure 2 : Concept 02

Figure 3 : Concept 03

4 AIM : TO BE easy to use straight away METHOD : research & user testing

4.3 103

interface AIMS

Once the casing had been developed and finalised, the interfaces process and aesthetic needed to be considered. This process and aesthetic needs to work alongside the physical product/casing, complimenting it. Figure 1 shows the target benefits for the interface and the methods that will be used to ensure they are met.

AIM : TO HAVE quick & easy set up changes METHOD : user testing

6 AIM : TO make studying pleasurable METHOD : moodboards & feedback

Figure 1 : Interface Aims

AIM 04 For the interface to be easy to use straight out of the box. Initial testing (see Human Factors point 3.4.) established that the initial set up interface process (from Task Analysis) was too time consuming and not very intuitive. This was because; •

The device did not show the user what the set ups are (they have to find them themselves)

•

The user had to set their preferences for each set up all in one go (they can’t do them as and when they have the need to).

•

The user was not made fully aware of what each set up can do before setting their preference.

Therefore the interface was developed to; •

Include a short 30 second introductory video that shows the device moving into each set up and what it can do in each one.

•

After the video the user will have the opportunity to experiment with the device finding each set up.

•

The user will be asked to set their preferences for each set up as and when they find them, rather than setting them up all in one go.

•

The user will be shown the selected display option over the whole screen before being asked to confirm.

These changes significantly reduce the amount of time it takes for the user to change the product into each set up and the number of errors (if any) that they make while doing so. Figure 1 shows the updated task analysis.

105

Figure 1 : Updated Initial Set Up Task Analysis

Figure 2 : Updated Changing the Set Up Task Analysis 107

SET UP DISPLAY CHANGE SYMBOL LOCATED ON THE button

too much like a repeat symbol & implies going around back to the same situation

implies more than one situation (double arrows) but does not clearly link to the set up/hinge

elongated form resembles the hinge more, linking the symbol to the set up change

2mm

SET UP CHANGE BUTTON

LOCATED ON THE side of the casing with the volume buttons

8mm

DEBOSSED SYMBOL Figure 3 : Set Up Change Button

AIM 05 For the process of changing the set up of the product to be quick. Although the developed mechanism is designed to enable fast set up changes the initial interface stopped the 15 second set up change target from being met. Although the user set preferences mean the set up change are quick in most cases, when the user does not want the set preference view and needs to change the display it takes longer than 15 seconds for the user to change the display to the desired one. The main reasons for this issue are that; •

The users cannot find the correct button/

option to change the view. •

The user has to go through the ‘would you like to make this your preference’ sequence.

Therefore to make the process quicker; •

A physical ‘display change’ button, which is much easier to find, will be added to the casing (this button was designed in line with Aim 2 and is shown in Figure 3)

•

The ‘would you like to make this you preference’ sequence has been removed, and the user will have to go to the device setting if they’d like to change their preferences (the new process/Task Analysis is shown in Figure 2).

spread the display over multiple devices

AIM 08 To encourage positive social interaction. One of the key features of the interface is the group work and sharing mode. This mode enables multiple users to tile their devices together and either; â&#x20AC;˘

Mirror one of the devices display onto the other devices

â&#x20AC;˘

Spread the display over all the devices to make one large screen to work from

â&#x20AC;˘

Swipe work from one device to another to share.

The illustrations on this page show the key group mode features.

mirror one devices screen onto another 109

AIM 06 - FUNCTION To make the task of studying more pleasurable. The following existing features of the product/interface aim to make the task of studying more pleasurable; •

Group work mode to encourage social interaction to help study (covered in Aim 08)

•

The use of technology to make the task of studying easier and more interactive

•

Ease of reading, making notes, typing, and sharing, due to the various set ups.

• The illustrations on this page show the key study mode features.

view documents & write notes

type on the keyboard

spread the display over 2 screens

swipe to share

quickly view a to-do list

AIM 06 - AESTHETICS To make the task of studying more pleasurable. By creating a mood board as inspiration and designing around it, a finished interface that resembles fun appâ&#x20AC;&#x2122;s such as games or networking apps rather than study apps/ programmes such as word processing, can be created.

4.4 interface build

In order to be deemed ergonomically acceptable the interface of the product must abide to the following points (Cornell University, 2013); Consistency The interface should be consistent (in behavior, terminology, icons, and colour) across all screens. Tasks/Processes Tasks/processes should be made simplier by; • • • • • •

Breaking them into smaller steps Using familiar icons Making them linear. Providing cues Requiring minimal user input Allowing the user to exit from all operations at any time.

Feedback (information & warnings) The interface must provide the user with warnings, reminders, and feedback when necessary, provided in a user centered way, by; • • • • •

Using real-world metaphors Giving feedback that confirms input Providing status indicators Not using distracting techniques such as flashing messages. Not displaying important information for limited periods

Appearance The interface must; • • • • •

Not use more than 4 different colors, font sizes, or font styles on a single screen. Use colours appropriately (for example red for danger and green for accept). Not significantly change in appearance/ layout from screen to screen. Allow some degree of customization of screen layout, appearance, icons etc Have plenty of empty space around text boxes (ideally 50%)

Reference

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Cornell University. (2013). Ergonomics Guidelines for Interface Design. Available: http://ergo.human.cornell.edu/ahtutorials/ interface.html. Last accessed 12th Feb 2014.

WIRE FRAME

SETTING INITIAL PREFERENCE 01

additionAL information in hidden box/button to avoid clutter Located in an area of easy reach (as per user testing)

ALLOWING THE USER TO EXIT AT ANY TIME

clearer icons/illustrations as per user testing feedback

clearly shows the user their selection before confirming

ICONS USED for ‘YES’ & ‘NO’ OPTIONS ‘YES’ icon is larger to indicate the advised options Located in an area of easy reach (as per user testing)

WIRE FRAME

SETTING INITIAL PREFERENCE 02

consistent layout of buttons

clearly confirms the users selection

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position of buttons slightly change to an area that is of easy reach for that set up

select to show/ hide additional information to avoid clutter but still provide all information

WIRE FRAME

SETTING INITIAL PREFERENCE 03

still remains consistent

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OPTIONs SHOWN only on master device to avoid confusion area of easy reach

WIRE FRAME

STARTING A GROUP STUDY SESSION

119

consistant with initial preference set up

takes users to documents folder to reduce steps needed

options hidden away until swiped up to avoid clutter

WIRE FRAME

SHARING FILES IN GROUP STUDY MODE

121

user drags document across to other device

devices confirm ‘yes’ & ‘no’ icons of a same size to remove indication

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expanded

Minimised

expanding Information /question box

Information /question box - without image Information /question box - with supporting image

aesthetic

Applied consistently throughout the interface

standard colours options

typography

example icons

icon boxes

line/instruction diagrams

YES/NO

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FINAL interface

4.5

127

129

FINAL PRODUCT

This render shows the final casing & interface combined. The use of consistent colour throughout both elements ties the product together really well.

PRODUCT REFINEMENT

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1. GOALS

Once the physical product and interface had been finalised the product needed to be refined. The aims for this area of development are to; •

Select suitable materials for the outer casing

•

Ensure that the product can be manufactured efficiently inline with the specification (using DFM, DFMA, & costing techniques)

•

Ensure the product is deemed safe (through reviewing the FMEA and product verification)

•

Model the product to create technical drawings & illustrative renders

These aims will be met using methods such as; CES edupak, solid based CAD, rendering, & research.

MATERIALS

A material selection process was used to find a material that would be suitable for the main outer casing of the product. The price and yield strength were plotted against one another in order to ensure that the material chosen was the best value for money. Then limits were applied (see Figure 1), including a maximum density (to ensure that the product remains as light as possible), a minimum hardness (to ensure that product is rigid enough to house the electronics), excellent water resistance (because the user many use the product with wet hands or in the rain), and excellent moldability for ease of manufacture. After all the limits had been applied there were 6 materials left on the graph to choose

Figure 1 : Applied Limits & Restrictions

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Figure 3 : Suggested Materials

from (see Figure 3). The properties of these materials were then put into a table for comparison (Figure 2), from which it was decided that the most suitable material would be â&#x20AC;&#x2DC;ABS/PC mixâ&#x20AC;&#x2122; this is because after further research it was discovered that the favoured option could not achieve the desired finish, and that the best alternative was a mix of the 2nd & 3rd favoured options. ABS/PC has all the positive features of PC but with the added benefit of being tougher and more crack resistant (Promolding, 2014). References Promolding. (2014). ABS/PC Mix. Available: http://promolding.nl/materiaal-munt. php?lan=uk&c=201. Last accessed 24.05.14.

Figure 2 : Plotted Results

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3. PARTS

4. DFM

137

Part Name : Main Body Back (Runner

& Spinner)

Part Description : The back section of

the main casing that holds the circuits & hinge mechanism. There are two variations of this part, one with a runner hinge section and one with a ‘fixed’ spinner hinge section.

Material & Finish : PC/ABS mix as

recomended in the material selection process, with a ‘spark’; slightly texture surface.

Process : Injection molding for high volume with the spark finish applied to the inside of the mold.

Part Name : Main Front Back (Runner & Spinner)

Part Description : The front section of the main casing that holds the circuits & screen. There are two variations of this part, one to attach the runner hinge back and one to attach to the ‘fixed’ spinner hinge back. Material & Finish : PC/ABS mix as

recomended in the material selection process, with a ‘spark; slightly texture surface.

Process : Injection molding for high volume with the spark finish applied to the inside of the mold.

References 3D Systems. (2014). Basics of Injection Molding Design. Available: http:// www.3dsystems.com/quickparts/learningcenter/injection-molding-basics. Last accessed 22.05.14. Protolabs. (2014). Recommended Wall Thickness for Injection Molding. Available: http://www.protolabs.co.uk/resources/ molding-design-guidelines/wall-thicknessrecommended. Last accessed 24.05.14.

Part Name : Customisable Back Plates Part Description : The back plate that

slots into the grooves in â&#x20AC;&#x2DC;Main Body Backâ&#x20AC;&#x2122;. There are two different versions of this part, one with the button cut outs and one without.

Material & Finish : PC/ABS mix as recomended in the material selection process with a soft feel coating (to give a silicone feel).

Process : Injection molding for high volume with the soft feel coating and colour applied as a spray afterwards. Allowing one mold to create multiply colours. 139

Part Name : Top/Bottom Plates Part Description : The plates that slot into the grooves on the top and bottoms of the â&#x20AC;&#x2DC;Main Bodiesâ&#x20AC;&#x2122; (sandwiched betweent them). There are four different versions of this part, two (top & bottom) for each main body. Material & Finish : PC/ABS mix as

recomended in the material selection process with a soft gloss coating (to ensure the hinge runs along them smoothly).

Process : Injection molding for high volume with a gloss coating.

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DFMA

References Bayer Material Science. (2012). Snap Fit Joints for Plastics. Available: http://fab.cba.mit. edu/classes/S62.12/people/vernelle.noel/ Plastic_Snap_fit_design.pdf. Last accessed 22.05.14.

Snap Fittings Snap fixtures are to be used to join the front and back main casings of each housing, this is because they eliminate the need for screws therefore reducing assembly time. Because the electronics & hinge mechanism, that may need maintaining over the products life span, are held within this casing it is important that separable snap fittings are used. The diagram on the right shows how the cantilever snap fit was adjusted to ensure that the back and front main casings are separable.

Lip & Groove Fixture Lip & groove fixtures are to be used to hold the top & bottoms plates into place between the back & front main casings. Manufacturing the top & bottom plates seperatly from the main casing has the following benefits; - Easy assembly of the hinge. - Easy replacement of the hinge mechanism. - Less complex molds (although more of them) The diagram on the right shows how the lip on the plate is held between the two main bodies.

Temporary Slot Fitting A slot fitting is to be used to hold the customisable back plates into place. Originally the back plates were going to be manufactured out of silicone, but due to the softness/flex of silicone it would have been really difficult to hold in place securely. Therefore the silicone was replaced with ABS/PC with a soft feel finish (that feels similar to a lightly sparked silicone). The diagram on the right shows how the lip that runs along the top and bottom of the back plate secures in the groove on the back main casing.

Part Reduction To reduce assembly time and manufacturing costs the numbers of parts within the product were reduced. Due to the hinge (which is different in each housing) the parts that make up the main bodies could not be reduced. Therefore smaller components were focused on. The diagram on the right shows the parts that were reduced.

6. COSTING

143

In order to ensure that the final product meets its target cost of £60 per unit costing was carried out. Quotes were gained from suppliers (through industry links), customparts. net, Alibaba.com, and CES Edupack. The results showed that it should be possible to produce the product for £52.38 (including a 10% contingency), which is £7.62 less than the target. References CIM. (2014). Molding Cost Calculator. Available: http://www.sourcing-cn.com/ moldcalc_result.asp. Last accessed 22.05.14. Recybase. (2014). Time Price List.

Plastics Real Available: http://

plasticker.de/preise/pms_ en.php? show=ok&make=ok&aog=A&kat=Mahlgut. Last accessed 22.05.14. Shenzhen Fastgo Electronics. (2014). Bulk Wholesale Android Tablets. Available: http:// uk.alibaba.com/product/1856532881-bulkwholesale-android-tablets-with-7.html. Last accessed 22.05.14. Venture Outsource . (2011). 2011 Report: China manufacturing hourly labor rate, compensation costs impact EMS. Available: https://www.ventureoutsource. com/contract-manufacturing/2011china-manufacturing-hourly-labor-ratecompensation-costs-ems. Last accessed 22.05.14.

145

7. TECHNICAL DRAWINGS

8. FMEA

147

To ensure that all possible failures of the product have been considered, and are not likely to be common or cause injury to the user an FMEA was completed. The first half of the table was completed at the beginning of the products development, then the areas of concern were worked on before the second half of the table way completed. This FMEA shows that the risk of/from each of the areas of concern have been eliminated or minimized.

PRODUCT REVIEW & VERIFICATION The sourced components have a 5 hour battery life

The tested wires are capable of transfer this data & power

The interchange back is available in 8 colours.

The back cover slides on and off easily. The tested circuit/ sensors activate each set up.

149

The final product is smaller than the specified maxium size.

The screen is inline with the user testing preferences.

This specification was referenced throughout development The screen has a ratio of 1.41:1.

The bezel is under 10mm on all edges.

The mechanism fully works with the chosen form.

Yet to be tested. But the product is designed for easy repair. Suppliers are yet to be sourced. The product is designed for easy repair.

The product is designed for easy repair.

FMEA on the final product was successfully carried out.

151

The plan was refered to throughout the development process.

Suppliers are yet to be sourced.

Suppliers are yet to be sourced. Yet to be tested.

The connectivity issues were resolved in the mechanism stage of development

Yet to be tested. But the product is designed for easy repair.

The sourced components can operate in temperatures from 0째 to 35째 C

The sourced components can withstand temperatures from -20째 to 45째 C

The sourced components can withstand this humidity

The materials selected have good resistance to all the listed chemicals.

The packaging is yet to be designed.

The form of the product is as per the user testing preference.

Yet to be tested.

The product will be stored in the closed positon leaving just the changable cover on show.

The final product meets all testing requirements. 153

This budget was exceeded.

155

Changes were made to the prototype to ensure this budget was not exceeded.

Yet to be tested.

The hinge mechanism passed user testing.

DFMA was carried out but the tooling costs are still very high. The sourced screen has a resolution of 165 ppi.

The product fits within these dimensions.

The buttons are slightly smaller than specified but passed user testing.

The screen fits within these dimensions.

The product weigh less than half the specified weight.

The brightness of the sourced screen is adjustable.

The contrast of the sourced screen is adjustable.

Yet to be tested. But the components are evenly spread through the device.

Yet to be tested. The interface was designed inline with these guidelines.

The volume of the device is fully adjustable using the side buttons.

The packaging is yet to be designed.

The prototypes were created using these facilities.

The following were considered in the material selection process but are yet to be tested.

The mechanism was tested using FEA.

The casing assembly meets this requirement but the circuitry assembly does not.

The packaging is yet to be designed.

MOQâ&#x20AC;&#x2122;s for all parts are 3,000 units.

All parts are either die cast or injection molded.

The casing and mechanism could easily accomodate new technology.

Suppliers are yet to be sourced.

Suppliers are yet to be sourced. The bumper design was altered but can still be changed using under 45N.

157

This deadline was not met, but a new revised deadline was.

The final product is design for easy disassmebly and repair.

The back plates can be easily wiped clean. The set up process was tested and takes under 30 minutes. The sourced components can hold 8GB of data. The sourced battery is low maintenance. Yet to be tested. The sourced components can view all these document types.

All standard Android updates would be available for the device.

All the materials used are available as ROSHH/ REACH compliant. Packaging and instructions are yet to be designed. All ports and switches are labelled. But the packaging is yet to be deisgned.

An FMEA was successfully completed.

Suppliers are yet to be sourced.

The sourced circuitry uses Mirco USB for charging.

Yet to be tested (Facilities & funding not available)

159

Yet to be tested (Facilities & funding not available)

Yet to be tested (Facilities & funding not available) None of the following Patents were breached.

The final casing was designed in line with these guidelines.

IP applications have been considered but not carried out due to lack of funds.

161

All plastics will be marked on the inside of the casing.

The sourced battery does not breach these guidelines.

The product is design for easy disassembly.

The product is design for easy disassembly & repair.

The packaging is yet to be designed.

CANâ&#x20AC;&#x2122;T FIND WHAT YOUâ&#x20AC;&#x2122;RE LOOKING FOR? TECHNICAL

PROTOTYPING

Assembly Drawing

135

Connectivity Prototypes

43 - 46

Connectivity (power & data transfer)

43 - 46

Electrical Prototype

57 - 60

DFA

141

Form Prototype

DFM

137 - 140

Mechanism Prototypes

29 - 34

Paper Prototyping (Interface)

85 - 90

Electronical Design Circuitry

49 - 52

Programming

53 - 56

Finite Element Analysis

35 - 40

FMEA

147

Interface Design

Wire framing

113 - 122

Aesthetic

123 - 128

Material Selection

41, 43, 133

Material testing

43, 93

Mechanical development

27 - 46

Product Specification

11 -26

Product Specification Review

149 - 162

Product Verificiation

149 - 162

HUMAN FACTORS Desirability Aims

Casing

92 - 102

Interface

105 - 112

Ergonomics

94 - 96, 75

Human Factors research

11 (in the spec)

Interface Design

Project Management PERT

Gantt

Proposed testing to standards

See specification

Wire framing

Aesthetic

123 - 128

Task Anaylsis

65 - 70, 105 - 107

User Testing

Schematics Exploded

135, 141

Collapsed

129, 131, 137, 139

Feature Labelled

Technical Drawing

113 - 122

Mechanism

77 - 82

Form

Interface

75, 85 - 91

36, 41, 145

*CE Marking was not applicable to this product as it falls under the voltage requirement. **Supporting files; such as CAD, full scale technical drawings and testing videos can be viewed at sianvygus.com 163

Si창n Vygus - 10818033 sianvygus@hotmail.com www.sianvygus.com