MARCH 2 0 1 6

VocalZoom Enables a

Human-to-Machine Communication Sensors Deliver

High-accuracy User Experience

Speakers and Smart Amplifiers

Printed and Flexible Sensor Technology

Interview with Tal Bakish – CEO of VocalZoom

Speech- activated Life

CLICK HERE

eeweb.com/register

Join Today

EEWeb

EDITORIAL STAFFContent EditorAlex Maddalena amaddalena@aspencore.com

Digital Content ManagerHeather Hamilton hhamilton@aspencore.com Tel | 208-639-6485

Global Creative DirectorNicolas Perner nperner@aspencore.com

Graphic DesignerCarol Smiley csmiley@aspencore.com

Audience DevelopmentClaire Hellar chellar@aspencore.com

Register at EEWebhttp://www.eeweb.com/register/

Published byAspenCore

950 West Bannock Suite 450

Boise, Idaho 83702 Tel | 208-639-6464

Victor Alejandro Gao General Manager Executive Publisher

Cody Miller Global Media Director

Group Publisher

Sensor Technology CONTENTS

8

18

24

4

NEWSWIRE

Time-of-Flight Signal Processing IC

PRODUCT WATCH

Humidity, Temperature, and Barometer Sensors from TE Connectivity

TECH REPORT

The Future of Printed and Flexible Sensors

Speakers and Smart Amplifiers: All about the Bass

INDUSTRY INTERVIEW

VocalZoom Enables a Speech-activated LifeInterview with Tal Bakish – CEO of VocalZoom

4

18

24

6

8

4

Sensor Technology

Time-of-Flight Signal Processing IC

Newswire

Intersil Corporation rolled out its innovative time-of-flight (ToF) signal processing IC that provides a complete object detection and distance measurement solution when combined with an external emitter (LED or laser) and photodiode. The ISL29501 ToF device offers one-of-a-kind functionality, including ultra-small size, low-power consumption, and superior performance ideal for connected devices that make up the Internet of Things (IoT), as well as consumer mobile devices and the emerging commercial drone market.

5

NEWSWIRE

The ISL29501 overcomes the shortcomings of traditional amplitude-based proximity sensors and other ToF solutions that perform poorly in lighting conditions above 2,000 lux, or cannot provide distance information unless the object is perpendicular to the sensor. Alternative solutions are too expensive, bulky or power hungry for use in small form factor, battery-powered applications. Based on Intersil’s patented technology, the ISL29501 sensor provides a small solution footprint and precision long-range accuracy up to two meters in both dark and bright ambient light conditions. Unlike competitive solutions, the ISL29501 allows customers to select the emitter and photodiode of their choice and configure a low power ToF sensing system customized for their application. To make system design easy for customers, Intersil offers a reference design featuring the ISL29501, emitter and photodiode, along with graphical user interface (GUI) software and user’s guide.

The ISL29501 applies Intersil’s power management expertise to save power and extend battery life through several innovations. The on-chip emitter DAC with programmable current up to 255mA allows system designers to select the desired current level for driving the external infrared (IR) LED or laser. This feature enables optimization of distance measurement, object detection and power budget. The device’s single shot mode saves power by allowing designers to define the sampling period for initial object detection and approximate distance, while continuous mode more accurately measures distance. The ISL29501 also performs system calibration to accommodate performance variations of the external components across temperature and ambient light conditions.

“Prior to Intersil’s time-of-flight technology breakthrough, there was no practical way to measure distance up to two meters in a small form factor,” said Andrew Cowell, senior vice president of Mobile Power Products at Intersil. “The innovative ISL29501 provides customers a cost-effective, small footprint solution that also gives them the flexibility to use multiple devices to increase the field of view to a full 360 degrees for enhanced object detection capabilities.”

KEY FEATURES AND SPECIFICATIONS

• On-chip DSP calculates ToF for accurate proximity detection and distance measurement up to two meters

• Modulation frequency of 4.5MHz prevents interference with other consumer products such as IR TV remote controls that operate at 40kHz

• On-chip emitter DAC with programmable current up to 255mA allows designers to choose the desired current level to optimize distance measurement and power budget

• Operates in single shot mode for initial object detection and approximate distance measurement, while continuous mode improve distance accuracy

• On-chip active ambient light rejection minimizes or eliminates the influence of ambient light during distance measurement

• Programmable distance zones: allows the user to define three ToF distance zones for determining interrupt alerts

• Interrupt controller generates interrupt alerts using distance measurements and user defined thresholds

• Automatic gain control sets optimum analog signal levels to achieve best SNR response

• Supply voltage range of 2.7V to 3.3V

• I2C interface supports 1.8V and 3.3V bus

6

Sensor Technology

I N S I G H T SPR DUCT

Humidity, Temperature,

and Barometer SENSORS from TE Connectivity

PRODUCT WATCH

7

For this Arrow Product Insights we will discuss TE Connectivity Sensor Solution’s Humidity, Temperature and Barometer Sensors. TE Connectivity Sensors Solutions offer a wide variety of sensors. We would like to showcase a few of TE Connectivity’s many sensors.

TE’s HTU21D humidity and temperature sensor is a three by three by point nine millimeter surface mount sensor that typically consumes less than half a milliamp when taking measurements and in the tens of nanoamps when sleeping. It outputs data in a calibrated, linearized signal via an I2C interface meaning this HTU21D humidity and temperature sensor is not only small and power efficient, but easy to use. This sensor’s optional PTFE membrane helps protect against contamination from water and dust without affecting response time. From small portable devices to home appliances and medical applications, TE’s HTU21D humidity and temperature sensor is perfect for any application.

Another sensor offered by TE is the MS5637 ultra-compact micro barometer, measuring a mere three by three by point nine millimeters. This highly sensitive barometer can be used in altimeter applications and can achieve a resolution of thirteen centimeters at sea level. With no external components, this simple I squared C interface contains no internal registers, making this an easy-to-use device.

TE Connectivity’s Sensor Solutions portfolio include a variety of other sensing devices such as force sensors, photo optic sensors and position sensors. To learn more about the wide range of sensing solutions available, search TE Connectivity Sensors at Arrow.com.

For more info on the latest products, join us for the next Arrow New Product Insights.

8

Sensor Technology

By Roger H. Grace President, Roger Grace Associates www.rgrace.com

Printed and Flexible SENSORS

The Future of

TECH REPORT

9

“During intense exercise or other physical activities, the system will assist users in determining the quantity, intensity, and chemical composition of the fluids that

the user will need to ingest to overcome the problems associated

with de-hydration.”

While there are

a number of

printed/flexible (P/F)

sensors available

today [1], leading

research universities

and institutes world-

wide are engaged

in even more

interesting,

advanced

developments.

10

Sensor Technology

Advanced Developments The Imec Holst Centre has developed several P/F sensors, including a solid-state, ion-selective electrode for monitoring pH, Cl, Na and K. Additionally, they are developing sensor labels built on ultra-thin (less than 150 µm) polyester foils that can measure humidity, temperature, chemicals, and gases and include NFC/RFID functionality.Northeastern’s Center for High-rate Nanomanufacturing (CHN) has developed a simple and highly sensitive multi-biosensor containing semiconductor single-walled carbon nanotubes (SWCNTs) that are enzyme-immobilized for detecting D-glucose, L-lactate, and urea in sweat (Fig. 1). CHN’s director, Prof. Ahmed Busnaina, notes that, “The utilization of semiconducting carbon nanotubes for electric detection results in high repeatability and sensitivity. By leveraging the advantage of the carbon nanotubes’ electrical response and enzyme reaction, fast, specific, and continuous detection is achieved. Printing of nanomaterials to create the sensor results in low manufacturing cost”. [2]

UCSD’s Center for Wearable Sensors is also developing biomedical sensors. Prof. Joe Wang of the Center explains that “Our team has developed a skin-worn tattoo-based wearable electrochemical device which includes electrolyte and metabolite sensors, a biofuel cell, and batteries [Fig. 2].  Temporary tattoos are attractive platforms for fabricating skin-worn devices.  Body-compliant wearable electrochemical devices on temporary tattoos couple highly favorable substrate-skin elasticity with attractive electrochemical performance.” [3]

Figure 1. Researchers at Northeastern University’s CHN have created a flexible biosensor, based on single-walled carbon nanotubes (SWCNTs), for real-time pathogen detection and physiological monitoring. Semiconducting SWCNTs are functionalized with specific molecules for detecting pathogens, glucose, lactate, urea, and such, and printed on a flexible substrate.

TECH REPORT

11

A few of Prof. Wang’s students formed Electrozyme (www.electrozyme.com) to commercialize this work. They have developed and licensed a flexible epidermal bio sensor system that can be used to determine the dehydration level of the wearer. The sensor suite consists of their P/F electrochemical sweat sensing device on a 7 x 40-mm PET substrate, along with several other externally sourced non-P/F sensors (which may include temperature and humidity at a minimum), and with some application algorithms provided by their “partner” customer. During intense exercise or other physical activities, the system will assist users in determining the quantity, intensity, and chemical composition of the fluids that the user will need to ingest to overcome the problems associated with de-hydration. Working with their integrator partner, this product (Fig. 3) is expected to reach the market in the second or third quarter of 2016, according to Electrozyme CEO Josh Windmiller.

Figure 2. Researchers at the University of California, San Diego, (UCSD) Center for Wearable Sensors have developed a printed/flexible/stretchable “tattoo” of electrochemical sensors that can be applied to a subject’s arm to monitor analytes — chemical constituent of interest in an analytical procedure.

Figure 3. Using intellectual property licensed from UCSD to create a wrist-wearable hydration sensor that will soon to be introduced by its development partner, Electrozyme uses its electrochemical chemical printed/flexible sensor with other, outsourced sensors to inform the wearer of what, when, and how much they should ingest to prevent dehydration. 

12

Sensor Technology

Another spin-out working on biomedical P/F technology, this time from Professor John Rogers’ materials science laboratory at the University of Illinois, is Cambridge, MA-based MC10 Inc. The MC10 team has been developing a new class of soft, conformal electronics and sensors that laminate on the human skin like a sticker. According to the company, the technology exploits inorganic materials with established fabrication and manufacturing strategies, coupled with mechanically optimized designs to allow extreme bending at any location on the human body. Their flexible electronics are tailored for healthcare, and specifically targets what they say are unmet needs in the movement and neurological disorders spaces, where accurate measurement of the magnitude and frequency of body movement is critical to assessing treatment and helping patients to become more actively engaged in care. MC10 has announced partnerships with UCB Pharmaceuticals and investments from Medtronic Inc. to deliver an end-to-end hardware, software and cloud storage and computing platform to this healthcare vertical. VTT is developing large area nano-photonic chemical sensors under the EU’s Photosens Program. The multi-parameter sensor platform is designed to be disposable and uses photonic crystals and/or SERS. Their effort features roll-to-roll (R-2-R) manufacturing.

Commercialization ChallengesAlthough P/F sensors have existed for decades, much of the impetus for developing them today is an outgrowth of

R&D undertaken by the displays industry over the past several years to create flexible displays. [4] Organizations are now aggressively pursuing P/F application solutions that include, at minimum, signal processing hardware and microcontrollers, along with proprietary embedded software whose algorithms are major product differentiators that enable a systems solutions approach. [5] It makes a great deal of sense to judiciously integrate P/F-based sensors into P/F-based electronics to create a unique, low-cost solution that meets many customer requirements; one such example is Thin Film’s Smart Label [1]. 

However, this is a potential challenge to the commercialization of P/F sensor-based application solutions. Developers and providers will need to select the optimum integration strategy for each application. Should these sensors be integrated monolithically or heterogeneously with other electronic functions — memory, logic, battery, antenna? Which of these functionalities should be manufactured in a P/F approach versus discrete or (more than likely) hybrid approach to create an optimum price/performance outcome? These questions are currently being addressed by several research and commercial organizations.  Most importantly, sensors that are manufactured as flexible or printed/flexible components can be sold in non-flexible packages (Fig. 4) to replace existing non-P/F sensors. The P/F companies mentioned in last month’s

TECH REPORT

13

article all stated that their P/F solutions had performance advantages over the “classical” three-dimensional versions. Joe Stetter, founder and CTO of Spec-Sensors (www.spec-sensors.com) who produces gas sensors stated it succinctly… “It is an issue of electronics vs. chemistry! In physics/electronics we are concerned about the movement of electrons, vs. that of ions in chemistry, and electrons move near the speed of light and are 10,000-times-or-more lower mass! So printed structures, [which] are smaller and reduce mass-transport effects, enhance the performance of the printed chemical sensors!”  It thus makes good sense to address the functionality of the sensor, irrespectively of its format (that is, printed/flexible versus discrete package) and how it satisfies the requirements of the design engineer from a specification, size, and cost perspective. So, as the architect John Louis Sullivan once remarked, “Form must forever follow function.” And P/F sensors can shift form.

Chris Salthouse, co-founder of the Center for Personalized Health Monitoring at UMass, states that “sensors, antennas, and actuators all frequently require large areas to effectively interface with the world. Fabricating these devices on flexible substrates has advantages, both because the finished product can conform to complex shapes and because it enables low-cost, high-rate, roll-to-roll production. The transistors required for computation, memory, and radio communications need to be small and high-performance, so today those transistors are best fabricated in traditional CMOS processing. Our

Figure 4. The small 15x15x3.8-mm electrochemical gas sensors shown before-and-after singulation; packaged with analog flex interface; and as a hand-solderable assembly make integration into standard PCB and flexible hybrid platforms possible. (Courtesy: Spec-Sensors)

14

Sensor Technology

current strategy at UMass is: optimize the integration of these small rigid CMOS components with large flexible substrates that contain sensors, antennas, and actuators. We are actively working to improve the performance of transistors fabricated on the roll-to-roll process to reduce the size and number of connections to the CMOS in the future, with the ultimate goal of building systems that are entirely fabricated on a roll-to-roll process.” Prof. Christoph Kutter and his team at Fraunhofer EMFT, through its

participation in the EU Interflex Project along with several collaborators, is vigorously addressing this important topic (Fig. 5). [6] Fraunhofer ENAS is also pursuing high volume R-2-R manufacturing and integration issues, as is Fraunhofer IZM.

For U.S. electronic companies who hope to participate in the P/F market, there is a special concern. From 2004 to 2016 period, foreign governments have been spending substantial amounts on P/F electronics. For that period, total government expenditures will amount

Fgure 5. This conceptual sketch of the demonstrator developed by Fraunhofer EMFT for the INTERFLEX project  shows three layers of different electronic functionalities: photovoltaics and energy storage, micro-controller IC and sensors, and wireless communication. The system was built using aligned, 3D-stacking of the film layers, in a process that combines hybrid component assembly and printing techniques.

TECH REPORT

15

REFERENCES

[1] R. Grace, “Printable/flexible sensors: valuable additions to the designer’s toolkit,” Electronic Products, June, 2015, pp. 26, 28.

[2] A. Busnaina, “Nanoprinting Scales Up,” The Wired World in 2015, Wired Magazine Annual Briefing, p.28.

[3] A. Bandodkar et al., “Tattoo-Based Wearable Electrochemical Devices: A Review,” Electroanalysis 2015, Wiley-VCH Verlag GmbH and Co., pp. 562-572.

[4] The Flexible Electronics Opportunity, National Research Council of the National Academies, The National Academies Press, Washington D.C., 2014.

[5] R.Grace and M. Maher; “Why MEMS-based systems solutions?,” Electronic Products, February 2011, pp. 17-19.

[6] K. Bock et al, “Multifunctional system integration in flexible substrates,”  Proceedings of the 2014 IEEE 64th Electronic Components and Technology Conference, May 2014, pp.1482-1487.

[7] Z. Kay, C. Curling; “Printed Electronics: Analysis of Competency Matrices for UK and Germany,” UKDL Newsletter, Winter 2008/2009.

[8] Dial-Up Sensors: Printed, Flexible and Organic Sensors for the Things in the Internet of Things, Lux Research, September, 2014.

About the AuthorWith a background that includes over 45 years in high-frequency analog circuit design, application engineering, project management, and product marketing, Roger H. Grace is the President of Naples, FL-based Roger Grace Associates, which he founded in 1982 to provide strategic marketing consulting in high tech. A MEMS pioneer, Mr. Grace has advised technologists and top executives on sensor and IC design, development, and commercialization at clients that include the international “Who’s Who” of corporations and government agencies. He received his BSEE and MSEE (as a Raytheon Fellow) from Northeastern University and was that school’s 2004 Engineering Alumni of the Year.

to $658M in Europe and $474M in East Asia. In the U.S., government investment in the same time frame will be a mere $176M—considerably less than half Europe’s and East Asia’s outlay [7, 8].  This discrepancy could have a detrimental impact on future competitiveness of U.S. technology firms.

Want to Know More?Roger Grace will make presentations on P/F sensors this year at MEMS Industry Group (MIG) Executive Congress (Napa Valley, CA, Nov. 4-6), the Sensors Global Summit (La Jolla, CA, Nov. 10-11), and Flex 2016 (Monterey, CA, Feb. 29 - Mar. 3, 2016). 

MYLINK

ORDER

http://www.cherrycorp.com

Upload Quote Order

Simple. Custom. Quality.

ZF Electronic SystemsEnergy Harvesting Products

Now Available!

No Wires.No Batteries.No Boundaries!

18

Sensor Technology

Speakers and Smart Amplifiers

By Russell Crane, Audio Marketing Manager and Matthew Kucic, Audio Systems Engineer Texas Instruments www.ti.com

It’s All About the Bass

TECH REPORT

19

Smart amps can improve your audio solution, compared to standard Class-D amplifiersRemember the days when you strung two tin cans together to make a telephone? Unfortunately, cell phone audio can sound a lot like those tin cans because of the miniaturization of devices, including the speakers. Unless you have upgraded your phone to a top-of-the-line handset over the last couple of years, you know that using your loudspeaker for either voice or audio can be, well, painful. That’s because handset manufacturers have been slow to make audio a differentiator in high-end handsets, and there is little low-frequency audio, commonly referred to as bass, present.

This is now changing thanks to a technology that we call smart amplifiers, or smart amps, because, unlike traditional amplifiers, they can safely and temporarily push the speaker to its limit. By sensing a speaker’s operation while playing music and applying advanced algorithms, smart amps can get a lot of sound out of a cell phone’s micro-speaker without hurting your ears.

20

Sensor Technology

What’s in a Speaker Today?Before we discuss how smart amps work, it is important to understand another key piece of the audio signal chain: the speaker. Regardless of the amplifier, if the speaker isn’t designed properly, no amount of audio processing or amplification will overcome its shortcomings. It would be like putting rocket-fuel in a lawnmower engine—all of that power and no way to use it. However, if you start with a reasonable engine, adding a smart amp is like adding a turbo charger to push it to the limits in a controlled manner. Speakers are constructed with a frame, magnet, voice coil, and diaphragm (Fig. 1).

Electrical current moves through the voice coil, which causes it to magnetize by reacting with the speaker’s fixed magnet. This motor causes the membrane attached to the coil to move up and down and emanate sound waves that are actually audible. We call the movement of the diaphragm excursion, and this excursion has limits. When the excursion limits are exceeded, audible distortion can occur. In extreme cases, a damaged speaker may result in failure. Traditional amplifiers use simple equalization (EQ) to limit the excursion. However, to protect across all speaker variations, operating conditions and audio signals, these filters are generally conservative—giving up the ability to push the speaker to its true limit.

Regardless of the amplifier, if the speaker isn’t designed properly, no amount of audio processing or amplification will overcome its shortcomings.

Figure 1. Anatomy of a speaker

TECH REPORT

21

A second problem with speakers is that, as current is pushed through the voice coil, some of the energy is converted into heat instead of sound. Push the speaker too hard and this heating can possibly damage the voice coil by melting the varnish on the magnetic wire. As the voice coil heats from the energy delivered by the amplifier, it must cool through the magnet into the surrounding structures. In traditional amplifiers, the maximum power is limited to a value that, if continually supplied, will not damage the speaker. This maximum power value must cover all speaker variations, operating conditions and signals. As such, this value is typically below what the speaker can handle and is, therefore, conservative.

What Makes an Amp Smart?How can we extract the most sound pressure level (SPL) from a given speaker and still ensure safe operation? We can use a smart amp. Audio has a peak-to-average ratio (PAR) that allows us to push the instant peaks while maintaining average or safe levels. Smart amps fall into two categories. The first is feed-forward, in which models of the speaker are created and the audio is fed through these models to predict the speaker’s behavior. Feed-forward tends to work well for larger speakers in which the variations are smaller and the operation is more linear. Even with larger speakers,

we must account for the speaker variations in the headroom, but the dynamic system can temporarily push the speakers to the limits to produce loud audio. Micro-speakers, commonly used in smartphones, require a slightly more advanced smart amp. The second category is feedback smart amps, which add current and voltage (IV) sense to the digital-to-analog converter (DAC) and Class-D of the feed-forward solution. This IV-sense allows us to directly measure the speaker’s voice coil temperature and detect changes in the speaker due to unit-to-unit variations, ambient temperature, and loading of the speaker (such as placing your hand over the speaker port). This information allows the algorithm to extract additional SPL from the speaker that otherwise would be lost by limiting the output to cover these variations.

To take advantage of the voltage and current sense information, smart amps need a processor (preferably a digital signal processor, or DSP) to parse this data and apply sophisticated algorithms to extract the best performance and sound while maintaining safe speaker operating conditions. Smart amps with or without integrated DSPs are available to meet the designer’s cost, time-to-market, and performance expectations.

How can we extract the most sound pressure level (SPL) from a given speaker and still ensure safe operation? We can use a smart amp.

22

Sensor Technology

Getting to Know Your SpeakerWith a basic understanding of how speakers and smart amps work together to deliver better sound at higher volumes, we can discuss how to get your product to market using this technology. The first step is to create a speaker characterization that measures numerous aspects of the speaker to identify its limits. These limits must be fully understood to get the loudest and highest-quality sound from the speaker without damaging it. Take detailed measurements to develop an accurate model of the speaker. One way to do this is with TI’s PurePath Console 3 (PPC3) along with a companion learning board; the combination can perform these measurements using an easy-to-follow procedure.  These measurements include, but are not limited to, system checks, excursion characterization, thermal characterization, and SPL measurements. Although the excursion measurement can be done using parameters from the speaker data sheet, a more accurate method is to use a laser displacement sensor to measure excursion and extract

the needed parameters. TI’s smart amp learning board allows engineers to easily characterize speakers by providing all the data acquisition needed using the laser, as well as a microphone for SPL measurements. Once complete, users can quickly view the different measured data plots, including excursion versus frequency and safe operating area limits.

TI’s PPC3 can simplify the tuning process. Its suite of sophisticated tools automatically merges the low-end impedance measurements with high-frequency microphone measurements. This creates a clean, full-frequency SPL measurement to begin the tuning. The low-frequency bass region can quickly be tuned to push the bass by easily selecting various alignment filters and allowing the software to automatically generate the needed compensation filters. The smart amp dynamically adjusts this filter to push the maximum bass without exceeding excursion limits. Next, the speakers voicing can be easily performed using SmartEQ. The user can simply specify the target EQ curve and PPC3 will calculate the necessary filters to adjust the speaker’s measured

TI’s smart amp learning board allows engineers to easily characterize speakers by providing all the data acquisition needed using the laser, as well as a microphone for SPL measurements.

TECH REPORT

23

SPL response to the target EQ. The tool does all the math, allowing the acoustic engineer to quickly obtain the results without the restrictions normally found in the competing EQ solutions.

Putting it all togetherWith speaker characterization and fine-tuning complete, it is important to ensure that your selections can operate safely and reliably across a larger sample of speakers. This reliability testing is an important step before taking your product to the assembly line. Invariably and regardless of speaker manufacturer, there is variance from speaker to speaker. Although the tuning sounds good and it appears to be within safe operating limits, additional speakers may not be as robust as the target you have been working on through the previous steps. It is recommended that you take a larger sample of your speakers through a lifetime test. This sample should be at least 20 speakers, which you should test over a longer time and across extreme temperatures to simulate your expected customer use-cases. Use the test results to adjust your final safe operating area parameters.

If you are using the TI TAS2555 smart amp, you do not need to integrate the smart amp sequencing and settings into the host processor, because a DSP is fully integrated into the smart amp. This greatly reduces software development time. Further, if your application processor is upgraded or changed, there is no need to re-integrate sequencing and settings.

As you move to the production line, a fast-and-robust test program can be implemented to ensure that the end product adheres to the parameters set during development. Production-line software can help screen the speakers, making sure they are within preset limits and were not damaged during assembly. Additionally, speaker-to-speaker impedance variations can be measured and stored. This step ensures that the full thermal headroom of each speaker can be used.

References1. Visit TI’s Smart Amp page for more information about TI smart amps. 2. Visit TI’s E2E Community Audio Amplifier Forum, where engineers ask questions and help each other solve problems.

24

Sensor Technology

VocalZoom Enables a

Interview with Tal Bakish – CEO of VocalZoom

Speech- activated Life

INDUSTRY INTERVIEW

25

Human-to-Machine Communication Sensors Deliver High-accuracy User ExperienceWhile having a conversation with robots may seem like technology reserved for Sci-Fi movies, the groundwork for that vision has already been paved. Speech recognition software has gained a lot of popularity in recent years, particularly with the debut of Apple’s Siri in the iPhone 4s. But the ongoing challenges associated with voice-activated commands and voice authentication are still being addressed, and many companies are working to smooth out the kinks in these systems.

Israeli-based startup VocalZoom has spent years developing proprietary optical sensor, utilizing military technology that maps out vibrations emanating from people when they speak. The company’s human-to-machine communication (HMC) sensor, coupled with the acoustic microphone voice signal, is then translated to a machine-readable sound signal that delivers one of the most accurate speech-recognition technologies on the market today. But developing this product was no easy task; EEWeb spoke with Tal Bakish, CEO of VocalZoom, about the technology behind this groundbreaking speech-recognition system.

26

Sensor Technology

How exactly did VocalZoom come about?

I was working for Cisco, where I was a hardware engineer. When I left the company in 2006, I joined some of my colleagues from college to work on a few projects. Back then, there was a lot of buzz circling speech recognition technology, and the challenges facing this new technology were huge. We sat down and tried to figure out if there was a completely different way to solve the problems for speech recognition. My colleagues and I had all studied Physics in school, so we started looking at technologies that were beyond the scope of microphones and we came up with a military technology that is commonly used for eavesdropping—it is a laser microphone that senses vibrations on windows. We thought if windows vibrate when you speak, then surely everything must vibrate when you speak.

We started looking into some academic research that was done on this subject

and began doing some experiments. We found that everything is vibrating around us when we speak, but more importantly, we found that the facial skin vibrates only because of your voice. From that point on, we started looking for a way to create a product that is small enough and low-cost that can measure facial vibrations in a very similar way that is used in microphones. This challenge took us around three years to overcome, but in 2010, we found a way to do it. From there, we founded VocalZoom and started moving forward.

How does your product work in collaboration with microphones?

The final goal is to reach a point where the sensor is independent and can perform and give input to a speech recognition system by itself. Today, products have microphones and audio processors and we are simply adding our sensor on top of that without making any hardware changes. This way, we improve the performance while working in

INDUSTRY INTERVIEW

27

conjunction with preexisting microphones. However, in the future, the sensor will be used independently for voice control and authentication without any microphones.

Does this technology serve other functions aside from speech recognition?

Yes. IoT and wearable devices all utilize sensor consolidation and we have developed an interferometer which measures distance and velocity. This can be used as a microphone to measure vibrations of audiobe used for 3D imaging, accurate heart-rate detection, proximity sensing, tapping detection, and biometric authentication. It is a multi-functional sensor with a very wide dynamic ranges that can be implemented in a lot of applications. For example,we have many inquiries from customers to measure vibrations in engines, turbines or industrial printers, for industrial IoT applications to collect information and send it to the cloud for analytics and detection of small anomalies.

How exactly does the sensor work?

The main challenge in the first few years of development was how to make this sensor very small and low cost. We decided to either develop an interferometer, which is very small but expensive, or go for a much more challenging option , which is based on the internal physics of a laser. In this method, we took the risk of being the first to make it robust enough to become a consumer product.

In most cases, an emitter and detector are required to perform measurement of distance and velocity (like time-of-flight based sensors), but with the method selected, the laser is used as the emitter as well as the detector. This fact enabled a super low cost design which has almost no optical components. The method we use is something that nobody has been able to put into consumer electronics before, it was always just an academic exercise. The challenges

We found that everything is vibrating around us when we

speak, but more importantly, we found that the facial skin vibrates

only because of your voice.

28

Sensor Technology

were very high. We had to overcome the noise issues related with this method, and measuring on non- reflective and changing surfaces like facial skin.We are very proud of the achievements.

What were some of the challenges you faced in developing this and how were you able to overcome them?

The biggest challenge with this technology is the signal-to-noise ratio. To achieve a working sensor in consumer electronics environment is very difficult given the diversity of use cases, environmental conditions such as lightning and temperature, and the fact that a person is always moving. All of those problems come down to the signal-to-noise ratio inside of the sensor. We are working to improve this ratio all the time, which means we are using better electronics, more sophisticated algorithms, better optics, and a better laser. Each one of these components is a project in itself. When you take

everything together, you eventually get to a certain performance where you can decide if it is good enough for a product.

We started developing our own laser in 2010. At some point, after having much better understanding of the physics, we discovered that we can take this laser off the shelf. This is an example of something we developed from scratch, but after two years, we found out that we can actually buy that from another company to keep costs down. We still develop our own laser for more advanced, future products.

On the application side, one of the biggest challenges for a startup that develops a sensor or other component, is to demonstrate the solution end-to-end and to be able to show the added value. The full solution requires customization of existing products to use the new sensor and most product companies are not willing to go through this process without a proof of commitment from end customers. For example, to connect the sensor to a speech recognition

The biggest challenge with this technology is the signal-to-noise ratio.

INDUSTRY INTERVIEW

29

software, you need to bring a company like Samsung to commit to buy, for the speech recognition provider to agree to make the required changes.

How is the iFLYTEK demo going and what can we expect from that in the next few years?

VocalZoom is working with a few partners to develop more advanced speech recognition and noise reduction technologies that are using optical sensors. In some cases the sensor is used to improve the noise reduction and by that improve the speech recognition performance and in other cases without the need for noise reduction by feeding the optical sensor directly into the speech recognition. We have reached disruptive performance with these technologies, which means in environments that have a lot of background noise, we can reduce the results of the speech recognition or voice authentication to very low error rate—far superior to the competition.

When will this be deployed commercially?

We have several customers already working on products. We have two phases in our go-to-market strategy: consumer electronics first and then automotive. We have some OEMs and suppliers that have been working with us to develop some proprietary products. The consumer electronics products will see the light of day in 2016-2017 and the automotive products will follow in 2018-2019.

VocalZoom is working with few partners to develop more advanced speech recognition and noise reduction technologies that are using optical sensors.

VocalZoom is working with a few partners to develop more

advanced speech recognition and noise reduction technologies that

are using optical sensors.

Click here

Sierra Circuits:A Complete PCB Resource

PLUS: The Ground ” Myth in PrintedCircuits

“

PCB Resin Reactor+

Ken BahlCEO of Sierra Circuits

Let There Be

How Cree reinvented the light bulb

LIGHT

David ElienVP of Marketing & Business

Development, Cree, Inc.

New LED Filament Tower

Cutting Edge Flatscreen Technologies

+

+

M o v i n g T o w a r d s

a Clean Energy

FUTURE— Hugo van Nispen, COO of DNV KEMA

MCU Wars 32-bit MCU Comparison

Cutting Edge

SPICEModeling

Freescale and TI Embedded

Modules

ARMCortex

Programming

From Concept to

Reality Wolfgang Heinz-Fischer

Head of Marketing & PR, TQ-Group

Low-Power Design Techniques

TQ-Group’s Comprehensive Design Process

+

+

PowerDeveloper

Octobe r 20 13

Designing forDurability

View more EEWeb magazines— Click Here