As we’ve written before, adding the sense of touch to prosthetic hands is essential to provide the feedback that the wearer needs to make natural use of the device. Scientists at the National University of Singapore (NUS) have come up with a novel approach for a lightweight, durable, and flexible sensor system.
The new device relies on microfluidics, in which tiny amounts of liquid flow through tiny channels. In this case, the researchers have created liquid suspension that includes non-corrosive, non-toxic nanoparticles of conductive material such as graphene oxide. These fill tiny cavities in a silicone membrane, and the electrical properties change when the substrate is subjected to pressure. These changes can be measured and used as inputs for a touch-sensing system.
The thin device is lightweight, flexible, and inexpensive to make. It is extremely robust, and can be folded, stretched, or rolled and still function. It can withstand a great amount of pressure without any harm; the researchers even ran over it with a car and it still operated reliably. This new approach could lead to the development of a synthetic skin, not just for prosthetic hands but for robotics and other applications.