"In software, we build the structure for the sensor technology," says Hidalgo, "we send this information to a 3-D printer where our soft sensors are produced." In the process, the printer introduces a conductive black paste into liquid silicone. While the silicone hardens, the paste remains liquid and is enclosed by the silicone. When the sensors are pressed or stretched, their electrical resistance changes. "This tells us how much a surface has been pressed or stretched. We use this principle to understand interactions with objects in general and, more specifically, to be able to control an artificial hand that interacts with these objects," explains Hidalgo. The special feature: The sensors embedded in silicone adapt to the respective surface (for example fingers or hands) and still reliably deliver precise data that can be used for interaction with the environment.