Touchpoints: Geeking Out and Saving Lives with Tactile Sensors


I’m most proud of the work I do with capacitive tactile sensors when that work disappears.

That is to say, I want to use cutting-edge capacitive tactile pressure sensing technology tosolve unique and challenging problems. And I want that technology to be integrated so seamlessly and simply that the people who use it never even think about it. Because, while I love dealing with the nitty-gritty of what goes on “under the hood” of a product that I’m helping to develop at Pressure Profile Systems (PPS), I know that most people, at the end of the day, don’t care about the mechanics of how their products function. They just want to be able to do their work.

Thus, the projects that I find the most personally gratifying are the ones that allow me to ‘geek out’ on specifics like architecture, expandability, and error correction while developing technology that, ultimately, gets out of the way and allows someone to do something they never could have done before.

One especially rewarding experience in that respect was working with Qualcomm and Medical Tactile Inc. (MTI) on the next-generation designs for the SureTouch Digital Breast Exam system, the origins of which were discussed by PPS CEO Jae Son in a previous blog post. Our goal on this project was to take the existing technology and incorporate it into a more user-friendly wireless platform. Doing so consisted of miniaturizing the sensor electronics and adding Bluetooth and 3G wireless connectivity. This “cut the cord” between the sensor and the Android tablet while tying the system into a much-larger network. Data could be uploaded and shared with experts, who could then assess and review results, removing the burden of doing all of the interpretation from the operator.

On a technological level, the tactile pressure sensors that I work with are really fun toys for an engineer to get to play with; they comprise a very fun toolkit. When I get to draw from that toolkit to make a difference in a way that’s exciting and rewarding beyond the basic technology involved, that represents a truly satisfying blend of fun and functionality.

For example, PPS worked with a group at a national veterans hospital on a technologically advanced liner developed for research on prosthetics for partial amputations of the leg, either above or below the knee. This liner, which is akin to a high-tech sock, was designed to be worn between the residual limb and a prosthetic; embedded tactile pressure sensors served to wirelessly transmit data about how well the prosthetic fit as the user performed various actions, such as walking and climbing stairs. Whereas before, the only way to get a sense of how a prosthetic limb fit was to ask the person wearing it, now it was possible to see and analyze pressure map data during actual use, which could be used to make adjustments.

This project required a significant amount of developmental work. The technology had to be stretchable enough to fit over a person’s leg, and the liner had to be comfortable enough to go unnoticed by the user. Furthermore, the product had to incorporate Bluetooth wireless connectivity and exhibit durability. And, ultimately, the sock had to incorporate all of these requirements in a package that was both easy to operate and inconspicuous. Once all that was achieved, it also needed an easy-to-use, automated system that could calibrate, test, and validate the sensor each time before it was to be used on a patient.

Perhaps the best part of my job is the range of products with which I’m involved. One day I’ll be working on life-changing projects such as the SureTouch product for early cancer diagnosis or the project with veterans; the next, I’ll be working with a company looking to verify the fit of a bike helmet or with the Navy to measure the pressures that would potentially face submarines attempting to break through ice.

Whatever the application, I derive great satisfaction from distilling complex problems down until there’s a solution. My background is in mechanical engineering, and I think that helps drive what I do. While capacitive tactile pressure sensors are electronic and involve software design and integration, ultimately, there is a mechanical phenomenon that we’re trying to capture in some way. One must have a real understanding of how the different pieces in a project fit together. How can we best incorporate a tactile pressure sensor? How can we capture the signal it produces, digitize it, and display it in a way that’s easy for the user to interpret? What is the real goal of the customer? There’s something very real and concrete about figuring all of that out. –David Ables, Chief Technology Officer, Pressure Profile Systems