Sensor Technology: September 2014

SEPTEMBER 2014

Skintight Technology Flexible Sensors Collect Vitals

Next-Gen Signal Conditioners Lighter & More Robust

Smaller Than a

Grain Sand

of

Interview with Ben Lee President and CEO of mCube

mCube’s Sensors Enable IoMT

SENSOR TECHNOLOGY

FEATURED PRODUCTS

Unipolar Switch with Self Diagnostics Allegro MicroSystems developed the A1160, a complete unipolar Hall-effect switch that is unique with any other devices. The device was released recently in January this year. The A1160 features an integrated coil that surrounds the Hall sensing element, and a built-in diagnostics. During normal operation, the device functions as a typical unipolar switch (output turns on in the presence of south-pole magnetic field and turns off when the field is removed), but, when the diagnostics pin is pulled high, it enters diagnostics mode. This patented feature allows current to pass through the integrated coils, generating ~20 G of magnetic field.

The proximity of the coils to the Hall sensing element allows the element to sense the field generated by the coil, while ignoring external fields. In diagnostics mode the device will output a PWM signal of 50% duty cycle when the device is properly sensing the internally generated magnetic field...Read More

2-Wire EOL Programmable Hall Effect Switch The MLX92242 is a 2-wire EOL programmable hall-effect latch/switch featuring customer end-of-line programming and programmable permanent magnet. It has reverse supply voltage protection and integrated self-diagnostic functions activating dedicated safe-mode.

The device integrates a voltage regulator, Hall sensor with advanced offset cancellation system and a current sink-configured output driver, all in a single package. Based on a brand new platform, the magnetic core is using an improved offset cancellation system allowing faster and more accurate processing while being temperature insensitive and stress independent. In addition a programmable temperature coefficient is implemented to compensate the natural behavior of certain types of magnets becoming weaker with rise in temperature...Read More

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ty, and emission requirements.

CONTENTS

f range o

4

TECH REPORT

Next-Generation Sensor Signal Conditioners Powerful and Flexible yet Easy to Use

TECH REPORT

Non-Contact ECG Measurement Possibilities with EPIC Sensors

INDUSTRY INTERVIEW

A

nalysts project that by 2020 there will be over 50 billion connected

es in the now-nascent

net of Things (IoT). However,

echnology that will enable the

mCube’s Super Small Sensors Ben Lee, President and CEO of mCube

12

20

f the future may look a little

rent than today’s—in fact,

may not be able to see it at all.

y new mobile devices require

on sensors in order to monitor,

yze, and deliver real-time data

analysis to improve the way

umers interact with everyday

nology. While traditional

or platforms require multichip

ules or stacked die within a

e, mCube, a new MEMS sensor

pany, is driving the emergence

nsor 3.0, which will lead the

lopment of the smallest

TECH REPORT Skintight Technology Flexible Sensors Collect Vitals

26

ors to date—smaller than a of sand.

to enable the kind of constant and complex data accumulation that the Biostamp promises.

In the interim, MC10 is partnering up with other medical and pharmaceutical companies to develop integrated sensor and monitoring products. The company plans to become a certified, medicalready partner for companies who don’t have access to this unique and proprietary technology. Even the U.S. Army has begun working with MC10 on militarygrade sensors that will add further safety features for troops in the field. This funding from NIH grants, Department of Defense grants, as well as foundation grants will help the company get one step closer to realization of devices so flexible that users might forget they’re wearing them.

“The company has been bringing on board app developers with cloud computing and algorithm development expertise to help support MC10’s devices.”

The Biostamp, a prototype from MC10, is a new kind of wearable device that will redefine “form” in “form factor”... pg. 26

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3

SENSOR TECHNOLOGY

Next-Generation

Sensor Signal Conditioners Powerful and Flexible yet Easy to Use

By David Grice, Applications Engineer Zentrum Mikrokelektronik (ZMDI), Dresden, Germany

4

TECH REPORT

SO MANY SENSORS, SO LITTLE TIME As demands increase for the number, type, and range of sensors in almost every product category, the difficulty of implementing them increases proportionately. This is especially true in the automotive arena, driven by efficiency, safety, and emission requirements.

Existing sensor technologies are inadequate to meet many of these new and more stringent requirements, spurring the development of a new class of sensors based on micro-electromechanical systems (MEMS). These new sensors are smaller, lighter, more robust, less expensive, and consume less power, but they also produce electrical signals that are smaller and more nonlinear than their bulkier counterparts.

5

SENSOR TECHNOLOGY

A

s the quality of output from transducers declines to meet application demands, system requirements such as measurement range, accuracy, speed, and power consumption continue to increase, squeezing the performance of sensor signal conditioning (SSC) circuits from both ends and making the task of designing them exponentially more difficult.

“One of the key features of next-generation SSCs is flexibility.�

NEXT GENERATION TO THE RESCUE In the same way increasing demands have spurred a new class of sensors, Zentrum Mikroelektronik (ZMDI) is developing and introducing the next generation of SSC products and technologies to the sensor marketplace. This article describes some of the most important and beneficial new features of these new SSCs.

FLEXIBILITY IS A BEAUTIFUL THING One of the key features of nextgeneration SSCs is flexibility. The types and combinations of physical quantities measured for products are growing rapidly and new SSCs must facilitate fast development of complex sensor modules with low component counts and a user interface that is easy to learn and use. This requires a signal interface that is configurable for a wide range of signals, and correction algorithms that are much more complex than second or third order polynomial curve fitting offered by previous generations of SSCs. For example, a single application might require the conditioning of two temperature inputs, one being a diode and the other a thermocouple, and two resistive pressure bridges with widely varying output levels, each of which require linearization and calibration.

Flexibility is not limited only to signal types and ranges, however.

Another dimension of configurability is required for the sequence of signal processing tasks. Typically, some signals must be acquired at a much higher rate than others and the

6

TECH REPORT quantization and correction algorithms must be reconfigured quickly from one measurement to another in a programmable fashion. In addition to this, sometimes it is necessary to perform math operations between signals, like subtracting two pressure inputs to generate a differential pressure output. The SSC must generate a userprogrammable sequence that samples the inputs in a defined order and rate, correct each signal according to a userdefined calibration algorithm, and combine the conditioned outputs into an orderly stream of data.

Finally, flexibility must include the number and type of output signals and protocols. Reliability, safety, weight, and noise constraints are also driving the creation of innovative new output protocols like single-edge nibble transmission (SENT) for the automotive industry. Next-generation SSCs must support new interfaces like SENT along with the traditional analog, one-wire, and serial interfaces such as *I2C™ and SPI. In fact, the SENT interface is output only, and requires an auxiliary interface like I2C to configure and calibrate the SSC.

integrity level (ASIL) for automotive applications. These requirements include detection and notification of faults due to open or short circuits, outof-range parameters, aging sensors, and excessive temperature. Additionally, the SSC must be able to monitor these faults while tolerant of shorts to ground or supply voltage, supply overvoltage conditions, or reverse battery connections.

“A highly efficient and powerful reduced-instruction-set computer coordinates numerous control and computational tasks.”

Another important feature for nextgeneration SSCs is the ability to perform self-testing and diagnostics to meet critical safety standards like the automotive safety

*I2C™ is a trademark of NXP.

7

SENSOR TECHNOLOGY

Figure 1. An example block diagram of a next-generation SSC from ZMDI.

PUTTING IT ALL TOGETHER Figure 1 shows the block diagram of a next-generation SSC. In this particular case, the SSC supports two temperature inputs—one resistive, one diode—and two resistive bridge inputs. The conditioning signal chain includes sensor check and common mode (SCCM) adjustment, multiplexing (MUX), programmable gain (PGA) from 1 to 200 V/V, and an analog to digital converter (ADC) with adjustable sample rate and resolution from 12 to 18 bits.

The SSC in figure 1 looks similar to other SSCs that are presently available, but most of its potential and flexibility lies in the calibration microcontroller (CMC). A highly efficient and powerful reduced instruction set computer (RISC) coordinates the numerous control and computational tasks necessary to provide the tremendous amount of flexibility required for next-generation SSCs. The controller also combines the multiple output data packets into a structured stream in a wide variety of formats that can be either analog or digital.

8

The cycle of tasks performed by the RISC engine consists of three main types: measurement tasks, conditioning tasks, and output tasks. Measurement tasks include operations that select the MUX input and signal polarities, the gain and offset of the signal path, the speed and resolution of the quantizer, and auxiliary tasks such as auto-zeroing gain stages. The output values of all the main measurement tasks are stored in registers for processing by the conditioning tasks. These tasks range from simple operations like shifting and synchronization to basic math functions such as add, subtract, multiply, and divide to complex functions such as logarithms, polynomial evaluation, spline curve fitting, and digital filtering.

Output tasks include synchronization of data streams, formatting, packetizing, encoding error detection, and safety features like redundancy or inversion.

The SSC shown in figure 1 provides for up to 20 measurement tasks and 62 conditioning tasks, enabling thousands

TECH REPORT of different combinations of signal processing sequences for each of the four inputs. The number of output tasks varies greatly depending on the type of output, but for a complex protocol like SENT, the number can be in the dozens.

MAKING IT EASY However, it is also vitally important that the flexibility, power, and complexity of next-generation SSCs do not require a commensurate level of time and resources for system designers implementing them. The example shown in figure 1 is a member of a product family that is preconfigured by the manufacturer for a specific application using firmware.

All of the measurement, conditioning, and output tasks are programmed so that the designer need only focus on determining gain, resolution, and calibration coefficients for the correction algorithm, all of which are facilitated by software that is easy to use and

consistent across the product line. Special use cases can be implemented easily in firmware by the manufacturer should the need arise, but the standard factory configuration will cover the majority of designs. Additional family members of the product line are optimized for different numbers and types of inputs and outputs and also preconfigured for the intended application use.

Finally, one thing that should not be flexible in next-generation SSCs is the user interface, including the physical dimensions, pin or pad locations, and software user interface. The product family exemplified in figure 1 has a standardized footprint, pinout, and software user interface to minimize the costs, time, and resources associated with board layout, calibration, and climbing the learning curve.

“One thing that should not be flexible in next-generation SSCs is the user interface.�

9

SENSOR TECHNOLOGY

Non-contact ECG measurement using EPIC Sensors Measuring electrocardiogram (ECG) signals without skin contact is now possible using novel Electric Potential Integrated Circuit (EPIC) sensors.

By: Alan Lowne CEO of Saelig Co. Inc.

12

TECH REPORT

T

he human heartbeat is arguably the single most important (“life-and-death�) diagnostic indicator. Thus electrocardiograms (ECGs) are one of the most significant diagnostic methods in that they monitor heart function. ECGs are not only used in a clinical setting but are increasingly seen in personal health devices. Traditionally, ECG measurement conductive electrodes have been applied which are directly attached to the skin. With the help of contact gel (wet or solid) to ensure that there is good electrical contact between the skin and the sensor, direct resistive contact is made with the patient. However, conventional electrodes possess various disadvantages which are not conducive for long-term use in non-clinical settings. In addition to being potentially messy, metal allergies can cause skin irritations and, as a single-use item, they are quite expensive.

13

SENSOR TECHNOLOGY

Non-contact measurement of electrophysiological signals is of great interest in healthcare settings, with the potential of reducing disposable costs, speeding up or simplifying measurement techniques. Monitoring long-term medical conditions within the home or observing pilots, drivers, soldiers, and others in safety critical situations is now possible without needing skin contact. Monitoring vehicle drivers for health and alertness by detecting heart rate and respiration, or determining car occupancy to adjust the ride, handling and air bag deployment with the varying size and location of occupants, is a vast potential market.

Capacitive (insulated) electrodes can register ECG signals without conductive contact to the body–even through clothes–and represent

EPIC Sensors in contact with clothing Output EPIC demo box Conductive fabric in contact with clothing, e.g. on chair seat

Figure 1: Basic configuration for non-contact ECG measurement including capacitively-oocupied DR circuit

14

an attractive alternative for a wide range of new applications. EPIC (Electric Potential Integrated Circuit) is a completely new sensor technology resulting from research at the University of Sussex (UK). Novel, ultra high impedance EPIC sensors measure electric field changes without requiring physical or resistive contact. This award winning, patent-protected sensor can rapidly measure electric potential sources such as electrophysiological signals or even spatial electric fields. It therefore has the ability to measure ECGs without direct skin contact. By adjusting the DSP and amplification circuitry, the sensors can be tuned for detection at a distance as required for differing automotive applications. EPIC sensor electrodes can be easily and discretely incorporated inside car seat backs to acquire the necessary biometric data.

Signals measured on the human body always include a large amount of noise, the major component of this being 50 or 60 Hz power line noise capacitively-coupled to the body from the surrounding electricity supply.

Measurements such as ECG depend on being able to extract the small electrophysiological signals from the much larger noise signals.

EPIC sensors can be used in “contact mode” for ECG measurement, where the subject touches both the capacitive electrode surface and some metal at the system ground directly with the skin. This ground reference allows filtering and differential amplification of signals from two sensors to be effective in removing the mains frequency noise, leaving a high quality ECG signal. In non-contact ECG measurement there is – by definition - no skin contact, and thus no direct connection can be made between the subject’s body and the system ground. Some other method of reducing the power line noise is therefore required to

TECH REPORT enable the ECG signal to be extracted reliably and accurately. One such method utilizes an approach very similar to the “Driven Right Leg” (DRL) system that is used for the same purpose in conventional ECG measurement techniques.

In conventional ECG the DRL signal is coupled directly to the patient’s skin. The DRL signal reduces power line noise on the sensor signals by feeding back an inverted average of the signals from two sensors on to the patient’s body. In non-contact ECG, the generated DRL signal can be capacitively-coupled to the body through clothing, via a piece of conductive material placed – for instance – on the seat or back of a chair. Capacitive coupling of DRL signals is described by Lim et al1 and Lee et al2.

SYSTEM DESIGN An ECG system can therefore be built into a chair, a mattress, or clothing for instance. The DRL circuit improves the sensor signal/noise ratio enormously. In the example in Figure 1, EPIC sensors are mounted on a chair back such that the electrodes touch the clothing on the subject’s back when resting normally against the back of the chair. The generated DRL signal is connected to a piece of conductive material

placed either on the seat of the chair, or at the bottom of the chair back, contacting the subject’s clothing in the normal sitting position.

Copper-coated nylon fabric is one possible material suitable for the DRL coupling material, but other conductive materials may be equally successful. A thin, non- conductive material such as a cotton fabric may be used to cover both the sensors and the DRL coupling fabric if required, for instance when building the sensors into a seat. Consideration must be given as to how material will reduce the coupling capacitance between the sensor and the subject, or add additional noise to the signals through static charging effects.

Figure 2 shows the design of the DRL circuit. It is a standard summing amplifier, generating an amplified and inverted signal that is the average of the individual signals A and B. The optimum value for Rf will be dependent on the type of sensors being used, as well as the clothing being worn by the subject being measured. It should be set to achieve maximum noise reduction, while ensuring circuit stability.

A value of 27kohms is suggested as a suitable starting point for EPIC sensors.

+5V

A Inputs from outputs of demo box B

Rf (27KΩ*) Ra (11KΩ) Rb (11KΩ)

Rp (1.5MΩ) OP-AMP

Vout

C (1nF)

To conductive fabric on chair, thus capacitively coupled to body

-5V

Figure 2: DPL circuit. Voltage gain is set by Rf; Rp limits current fed back to the body (see text).

Operational amplifier output Vout = - (VA + VB) * Rf 11K

15

SENSOR TECHNOLOGY

"Monitoring long-term medical conditions within the home or observing pilots, drivers, soldiers, and others in safety critical situations is now possible without needing skin contact."

Rp, the protection resistor, is included to limit the current that can be fed back to the human body. This resistor is essential in ensuring that the subject’s wellbeing is not endangered and must not be omitted.

IMPLEMENTATION The demonstration of non-contact ECG is best performed using an EPIC demonstration kit, Plessey part no. PS25003, which includes the necessary drive circuitry and switchable 50Hz and 60Hz notch filters. The inputs to the DRL circuit can be taken from the BNC outputs “A & B” on the front of the demo box. The DRL circuit will require its own bipolar power supply: ±5V or ±6V is suggested. A circuit design including a battery power supply is shown in Figure 3.

Plessey’s compact sensors (PS2520x) and disc sensors (PS25101) provide equally good results, although for demonstration purposes, disc sensors are simplest to fix to a chair to make contact with the occupant’s back. Compact sensors are recommended when designing a custom-built system.

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EPIC sensors which are designed for contact electrophysiology sensing give excellent results in most cases. Initial trials suggest that custom modifications to the sensor design (e.g. lower gain and higher input impedance) can offer increased sensitivity and the ability to detect weaker ECG signals.

The shape of the measured ECG trace – in terms of relative magnitudes of the P, Q, R, S and T waves – will depend on the positioning of the sensors behind the subject’s back. If the desire is only to measure the “R-R” interval to determine heart rate, then the positioning of the sensors is not critical. Placing one sensor either side of the spine, separated by 6” -10” (1525 cm), at approximately the same height as the heart is recommended as a starting point.

For applications where signals from other parts of the cardiac cycle are required the user should refer to texts on bio-electronic signals for guidance on sensor position.

SETTLING TIME When a subject first sits in the chair and leans against the EPIC sensors, the changes in electric potential will normally send both the

TECH REPORT

sensors and the DRL circuit into saturation.

Because the system contains some large impedances, and hence has some very long RC time constants, settling times of tens of seconds can be needed before a clean ECG signal is seen. During this period the signal can either appear very noisy, or be virtually flat, depending on whether one or both sensors, or the DRL circuit, are “railing”. The subject should sit still during this time and wait for the circuit to settle, since continually adjusting position will only make matters worse. Settling times can sometimes be reduced by turning off the power to the demo box for a few seconds.

to two layers of cotton material have been successful. Examples are shown in Figures 6 and 7. If the key greatest interest is in the “R-R” interval, adjusting filter settings to reduce or re-center the signal bandwidth can give improved signal quality.

STATIC Because there is no direct physical contact between the subject and any grounding point, there is no path for any static build up to be discharged. Under most circumstances, static build-up does not present a problem, but depending on factors including clothing, footwear, flooring, humidity levels in the air and so forth, static build up can sometimes prevent the cardiac signal from being seen clearly. Product design must take into account a discharge to the system ground to remove the static charge.

CLOTHING Good results can be obtained with one or two layers of cotton material between the sensors and the skin. Other materials, including a woolmix sweater and a polyester fleece in addition

1 2

10µF

3 4

7660 Switched Capacitor Voltage Converter

+6V

8 7

A

6 5

10µF

B

Ra (11K) Rb (11K)

Rf (27KΩ*)

OPAMP

Rp (1.5MΩ) Vout

DRL Output

1nF

6V battery pack 4xAA

-6V

Figure 3: DRL circuit including battery power supply and voltage converter to provide -6v rail. Inputs A and B are buffered outputs from the sensors and may be taken from the A and B outputs of the EPIC demo box.

Ground should be connected to the sensor 0V, the shielding of the BNC A and B outputs on the demo box being a suitable connection point. See figure 2 and the text for further comments on the DRL design.

17

SENSOR TECHNOLOGY

CABLE SHIELDING Careful shielding is necessary to reduce unwanted noise artifacts. Grounding the shielding of the sensor cable via the connection between the outer casing of the sensor plugs and the metal surround of the socket on the control electronics is recommended.

CONCLUSION EPIC sensors can be used to measure ECG signals without physical skin contact. While

sensors can be embedded in a chair or seat, the techniques are equally applicable to sensors mounted on a mattress, in clothing or in other situations. There are many variables that will affect signal quality, from the strength of cardiac signal generated by the individual being measured, to clothing, to the surrounding environment, but the designs given here are a starting point in establishing an optimum system for a particular application. ∞

Figure 4: Non-contact ECG signals measured through a single layer of cotton clothing with a capacitively coupled DRL circuit. HP filter corner frequency is 50mHz, LP filter in demo box has corner frequency of 30Hz.

Figure 5: Non-contact ECG signals measured through a single layer of cotton clothing with a capacitively coupled DRL circuit. Software filters limit the bandwidth to 8-25Hz.

Figure 6: ECG signals measured from a subject wearing a wool-mix sweater over a cotton shirt. Sensors attached to the chair-back were covered with an additional layer of cotton material. Filter settings limit the bandwidth to 8-25Hz. The heart rate can be easily extracted

Figure 7: ECG signals measured from a subject wearing a polyester fleece over a cotton shirt. Sensors attached to the chair-back were covered with an additional layer of cotton material. Filter settings limit the bandwidth to 1640Hz. The heart rate can be easily extracted.

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SENSOR TECHNOLOGY

Smaller Than a

Grain Sand of

mCube’s Sensors Enable IoMT Interview with Ben Lee President and CEO of mCube

By EEWeb Contributing Writers

20

INDUSTRY INTERVIEW

A

nalysts project that by 2020 there will be over 50 billion connected

devices in the now-nascent Internet of Things (IoT). However, the technology that will enable the IoT of the future may look a little different than today’s—in fact, you may not be able to see it at all.

Many new mobile devices require motion sensors in order to monitor, analyze, and deliver real-time data and analysis to improve the way consumers interact with everyday technology. While traditional sensor platforms require multichip modules or stacked die within a device, mCube, a new MEMS sensor company, is driving the emergence of Sensor 3.0, which will lead the development of the smallest sensors to date—smaller than a grain of sand.

21

SENSOR TECHNOLOGY

“Motion sensors are key components in consumer devices,” says Ben Lee, president and CEO of mCube. The need for smaller, more powerful sensors has emerged from the rise in mobile applications such as gaming devices, tablets, sports equipment, and wearable technology. This wave of new applications is a part of the Internet of Moving Things (IoMT), which depends on highfunctioning sensors like accelerometers, gyroscopes, and magnetometers, to deliver dynamic performance specs for these moving devices. mCube has developed microelectromechanical system (MEMS) sensors with significant size reductions that allow for simplified integration and implementation in new IoMT applications.

To achieve MEMS integration with electronics, mCube developed a monolithic, single-chip structural design that is integrated with an applicationspecific integrated circuit (ASIC). “mCube is the first company,” tells Lee, “to successfully bring to market an integrated MEMS+ASIC in high volume production.”

Whereas traditional MEMS devices occupied a larger area with lower yields, mCube’s MEMS is fabricated directly on top of the complementary metal-oxide semiconductor, allowing for unparalleled integration and performance. This is achieved by bonding a single crystal silicon wafer to the surface of a CMOS plate. A cap is then bonded over the MEMS structures at the wafer level and is protected in a hermetic environment.

mCube Technology Leapfrogs Existing Players

Cost, Size, Power

Hybrid / MCM

Stacked Chip 3D Single-chip MEMS IC

Performance, Function, Integration Proprietary and Confidential. © 2014 mCube, Inc. All rights reserved.

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11

INDUSTRY INTERVIEW With this unique process, mCube is able to overcome traditional drawbacks of integrating MEMS due to the fact that it is entirely monolithic, meaning the alignment tolerance between MEMS and CMOS in mCube’s accelerometer is 0.1 μm as opposed to traditional distances of 3 to 5 μm. As consumer needs are driving rapid size reductions in the IoMT market, mCube positions itself ahead of the curve by enabling integrated, powerful, and seemingly invisible sensor technology.

Just how small is mCube’s solution?

Maximum size reduction is achieved by ohmically connecting the MEMS to the underlying CMOS through 3 μm vias. mCube’s integrated device has four times fewer the number of connected bonds, which ends up significantly reducing the surface area needed for implementation and, ultimately, the cost.

“mCube has developed MEMS sensors with significant size reductions that allow for simplified integration in new IoMT applications.”

The mCube monolithic, single-chip platform, shown above in a schematic cross-section, integrates MEMS with CMOS more efficiently than in any other commercial MeMS product.

23

SENSOR TECHNOLOGY

As of 2014, mCube’s complete intertial sensor portfolio contains an accelerometer, magnetometer, and its proprietary iGyro™ gyroscope offering nine degrees of freedom (9DoF). Through reductions in cost, power consumption, and size, mCube’s sensor offerings make it possible to place them onto nearly any object or device—in some cases without packaging. “We aspire to put one or more MEMS motion sensors on anything that moves,” remarks Lee. And with the IoMT taking shape, and consumer expectations for connected moving devices becoming more concrete, developers of new applications will turn to solutions like mCube to deliver truly cutting-edge, Inertialconnected Motion devices.

Sensor Portfolio

Since sensors are so small and affordable, don’t be surprised to find unique applications in the future. Lee speculates that “farmers might have sensor tags to monitor livestock for abnormal activity, patterns of grazing, potential illness and herd behavior.” Commercial trucking might involve motion sensors connected to video cameras in rear-view mirrors to better assess the cause of an accident and driving conditions. For shipping, Lee describes “motion sensors embedded directly onto packages to record jarring motions or accidents in order to determine when and how contents were damaged.”

Complete

Accelerometer

Magnetometer

iGyroTM

3DoF 3DoF

3x3mm 2x2mm

3DoF 1.4x1.4mm 3x3mm 6DoF

9DoF

3x3mm

Solutions for up to 9DoF (Degrees of Freedom)

“At mCube we aspire to put one or more MEMS motion sensors on anything that moves.”

Proprietary and Confidential. © 2014 mCube, Inc. All rights reserved.

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15

SENSOR TECHNOLOGY

SKINTIGHT Technology Flexible Sensors Collect Vitals

By Alex Maddalena, Contributing Writer

26

TECH REPORT

Electronics are becoming increasingly omnipresent in our everyday lives. Industry trends of reduced device sizes, seamless integration in our environments, and wireless connectivity are changing the way consumers interact with technology. One of the upsides of ubiquitous technology is the collection of data that was previously inaccessible. An example of this is wearable health monitors—bracelets and bands that collect vital health statistics to inform users of trends in their everyday activity, which could ultimately lead to healthier lifestyle and activity choices. However, one of the biggest burdens of these health monitors is their form factor— rigid electronics are not the most natural option for wearing during physical activities.

27

SENSOR TECHNOLOGY

A

s a result, MC10, a flexible device developer based in Cambridge, Massachusettes, is developing a new kind of wearable device with UCB, a patient-centric biopharmaceutical leader, that will redefine “form” in “form factor.” The Biostamp™, a prototype from MC10, is a flexible sensor that effortlessly adheres to the body and is able to bend, stretch, and flex along with the user. The device is as unobtrusive as a Band-Aid that can link to any bluetooth-enabled mobile device to deliver real-time data on the body’s vital statistics—everything from hydration levels and heart rate, to UV exposure and body temperature. The Biostamp will enable users to receive real-time data about their health.

MC10 was founded by Professor John Rogers back in 2008 after years of seminal research on flexible technology at Bell Laboratories and UIUC (University of Illinois Urbana–Champaign). The goal of the research was to develop ways of implementing electronics everywhere imaginable by breaking down the device’s form factors. Rogers and his colleagues eventually developed a way to form silicon on incredibly thin elastomers while still maintaining its properties.

MC10 is the culmination of this extensive

28

and groundbreaking research and is the exclusive licensee of the patent portfolio that Professor Rogers built up over the years of research.

The innovations in materials science revolved around the deconstruction of the base material, silicon. Rogers’ team was first able to dramatically reduce the thickness profile of the silicon down to a nano scale. The second innovation was the development of discrete chiplets of silicon, which could then be distributed onto arrays comprised of nanomaterials.

In the case of the Biostamp, the array is then embedded onto flexible, rubber band-like material that still maintains the silicon semiconductor characteristics, allowing for unprecedented uses adhering to the human body, and this allows continuous monitoring.

“Professor Rogers is very passionate about the idea of being able to change people’s lives through electronics,” said head of market development, Nirav Sheth, offering a summary of the company’s mission statement. “At MC10, we are all about dissolving boundaries between humans and electronics.”

The Biostamp’s functionality reflects the central tenets of the company by

TECH REPORT “The Biostamp device is as unobtrusive as a Band-Aid and can link to any mobile device to deliver real-time data on the body’s vital statistics.”

collecting data that will ultimately help users make important decisions about aspects of their health. In fact, the device is undergoing crucial patient testing to determine the efficacy of the data it yields and whether it can provide concrete claims on the health of the user. “We never looked at MC10 as a purely consumer technology company,” Sheth claimed. “It is also a medical health company.”

Considering themselves a medical health company poses a unique challenge to the MC10 team because the market for ubiquitous technology like the Biostamp does not fully exist yet. However, this does not deter MC10 from continuing development of the device on all fronts— from material sciences research to software and hardware development. In fact, the company has been building its team by bringing on board app developers with cloud computing and algorithm development expertise to help support MC10’s devices in the back end. “The software aspects may be, in the long term, the most differentiating aspects of the technology,” Sheth stated, explaining the company’s software-related investment. Conversely, the hardware had to be at a certain advanced level

“We never looked at MC10 as a purely consumer technology company,” Sheth claimed. “It is also a medical health company.”

29

SENSOR TECHNOLOGY

to enable the kind of constant and complex data accumulation that the Biostamp promises.

“The company has been bringing on board app developers with cloud computing and algorithm development expertise to help support MC10’s devices.”

In the interim, MC10 is partnering up with other medical and pharmaceutical companies to develop integrated sensor and monitoring products. The company plans to become a certified, medicalready partner for companies who don’t have access to this unique and proprietary Affordable, versatile, and easy to use, the Tiva READY TO LAUNCH technology. Even the U.S. Army has Series Connected LaunchPad is well suited for begun working with MC10 on militarya broad audience and promises to facilitate For the launch of the Tiva C Series Connected the expansion of ingenious IoT applications in LaunchPad, TI has with Exosite, grade sensors that willpartnered add further safety the cloud. As Folkens concluded, “The target mentioned briefly toThis provide easy features for troops in above, the field. audiences actually are the hobbyists, students access to the LaunchPad from the Internet. The funding from NIH grants, Department and professional engineers. A better way of LaunchPad takes about 10 minutes to set up of Defense grants, as well as foundation looking at it is that we are targeting people with and you can immediately interact with it across innovative ideas and trying to help them get the will Internet do things get like one turn an LED on grants helpand the company those ideas launched into the cloud.” off remotely fromof the website stepand closer to realization devices soand see the Join the reported temperature as well. It can also display flexible that users might forget they’re approximate geographic location based on DESIGNERS OF THINGS wearing them. IP address and display a map of all the assigned conference in San Francisco on other connected LaunchPad owners if they are September 23 and 24. active and plugged-in to Exosite. “In addition, it supports a basic game by enabling someone to Dedicated to the explosive and exciting potential of Wearable interface to the Connected LaunchPad through Tech, 3D Printing, and the Internet of Things, the conference a serial port from a terminal while someone else is playing with them through their browser. provides the growing design and development community It is basically showing how you can interact around these technologies a meeting place to discuss and remotely with this product and a user even if showcase the newest products. you are across the globe,” Folkens explained.

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