The sensor skin is very flexible and can be attached to many surfaces, including fingers, for example. (Credit: Andreas Heddergott/TUM)

Researchers have developed an automatic process for making soft sensors. These universal measurement cells can be attached to almost any kind of object. Applications are envisioned especially in robotics and prosthetics.

Unlike traditional sensors, these soft, skin-like sensors wrap around objects. The group developed a framework that largely automates the production process for this skin. They used software to build the structure for the sensory systems and then sent this information to a 3D printer where our soft sensors are made. The printer injects a conductive black paste into liquid silicone. The silicone hardens, but the paste is enclosed by it and remains liquid.

When the sensors are squeezed or stretched, their electrical resistance changes, which indicates how much compression or stretching force is applied to a surface. The sensors embedded in silicon adjust to the surface in question (such as fingers or hands) but still provide precise data that can be used for the interaction with the environment.