Electrick: Low-Cost Touch Sensing Using Electric Field Tomography

Well I guess you have a topic for your next whitepaper. :D

The paper seems to say they use 200 kHz sinusoidal waves for the field. If that translates directly into what I see in an FCC table of frequency allocations, then that is in the AERONAUTICAL RADIONAVIGATION regulated by FCC Rule Part Aviation (87) [1]. They are driving the signal at 6 Vpp (peak-to-peak), at most 0.42 mA current with the lowest-resistance spray. I don't know how to even crudely calculate radio interference from those specs, so would appreciate someone giving guidance on where to look for a start.

What worries me about this approach is the need for calibration. I don't see anywhere that indicates they've tested to see the effects of the wearing down of the topcoat and conductive spray layer upon the accuracy. It would be cool to be able to simplify a light switch installation to slap(electrodes)-spray-spray-calibrate, it would suck if I had to re-calibrate once every few years.

Now if we can figure out how to beam low-voltage, low-amperage power over building distances and through insulation, then we could remove a lot of copper runs. Beam just enough low power to drive and sense these kinds of control surfaces, and control relays sitting in front of the actual devices' electrical connections.

[1] https://transition.fcc.gov/oet/spectrum/table/fcctable.pdf

I'm imagining a replacement skin that sends touch signals to the brain, so if you've lost an arm you can feel using your prosthesis. I know it wouldn't work for non-living objects, but imagine being able to regain the sensation of human touch.

"Touché: Enhancing Touch Interaction on Humans, Liquids, and Everyday Objects" [1] and "Botanicus Interacticus: Interactive Plant Technology" [2] used a single electrode and machine-learning classification in order to distinguish between different types of touches and touch locations.

Using multiple measurements (as Electrick does) provides much more robust tracking than these.

[1] http://www.chrisharrison.net/index.php/Research/Touche

[2] https://www.disneyresearch.com/project/botanicus-interacticu...

It's better than existing technologies in the sense that you can put it on a vastly wider array of surfaces. This looks like a very early iteration; I expect the technique could be improved upon to yield higher accuracy and support for multiple touches. More electrodes, smarter electrode coordination, better conductor regularity, etc. could probably all help. Even without these things, it already seems quite useful.

You're missing the point. Currently capacitive touch interfaces require a grid of copper and an MCU. This new technique lets you add the interface to any object that will take a thin film spray, which is great! The same issues with false positive rejection from humidity and moisture and radio noise exist, but now we can add it to arbitrary objects like handles and such without busting ourselves integrating the copper loops into whatever device it is we're building. You can just spray the surface, calibrate, and go. Lots of great design space here.

Video made it look pretty decent in terms of resolution -- notice the author move his finger around and trace the line. This isn't like 16 points total.

While I agree with you that transparent touch screens are currently underutilized in the sex industry, this technology will enable things beyond your wildest dreams.

Did you watch the video? They explain it fairly well.

How about ELI15? Touching a conductive surface reduces voltage in that area. Place sensors around the perimeter, and rotate the source of voltage to triangulate the location.