May 21st, 2021—
The field of soft tactile sensors is fascinating, as they grant robots the ability to move more freely or have greater granularity. Soft sensors also allow for human-computer interfaces to feel more interactive. However, previous sensors like these required multiple devices or complex wiring, making them difficult to use. To address these challenges, researchers from the University of Tokyo and Mercari R4D were able to come up with a way to integrate touch-sensitive pads onto a piece of foam, which they call “foamin.”
Foamin consists of a small piece of foam that has a series of conductive rows on its surface. These strips are separated by air, which is an insulator, thus creating a capacitor. When a human’s finger glides across, both the capacitance of the overall circuit and the resistance change. This impedance is measured by a single wire with an Arduino Uno, and after some data filtering, the team had a set of 60 data points per gesture. They then trained a model with this data and were able to achieve an accuracy of 100% when a mesh shield was attached.
This system is amazing for a whole host of possible applications. The researchers suggested using foamin as a musical instrument (similar to a launchpad), a numeric keypad, and even as a smart cushion to sense which posture the sitter is currently in.
You can see more about the project in the team’s published paper and in the video below.