Syntouch, a startup company associated with the University of Southern California, is in the business of developing tactile sensors for prosthetic and robotic applications. Their primary tactile sensor platform is called the BioTAC, and the firm’s website has some great videos looking at the underlying technology which goes into making these types of sensors.
The BioTAC prototype system has the form factor of a finger tip and features 3 types of sensors for providing tactile feedback. The primary pressure sensor consists of an array of electrodes covered in a conductive fluid which lies between an exterior membrane of textured skin and the interior electronic housing. When the outer membrane comes into contact with an object the conductive fluid is displaced producing large changes in the electrical impedance detected by the electrodes in the array. This change in impedance at each of the electrode locations can then be used to estimate the magnitude and location of the force in contact with the Bio-TAC.
In order to provide additional feedback for textured surfaces, the conductive fluid is also coupled to a pressure sensor which detects sounds waves generated by the vibration of the fluid as it moves over the surface. As different textured surfaces produce unique vibration patterns, the Bio-TAC can identify a given texture from its associated vibration waveform.
Just in case that wasn’t enough, Syntouch also included a thermsistor to detect temperature changes at the outer membrane. Check out this video for a more detailed look at the Bio-TAC system in use.
Product page: Syntouch technology page…