One goal of making robots in a humanoid form is to let them interact closely with people. But that will only be possible if a robot is fully aware of what its powerful motorised limbs are in contact with [before destroying the puny human].
The skin is made up of triangular, flexible printed circuit boards which act as sensors. Each bendy triangle is 3 centimetres to a side and contains 12 capacitive copper contacts. A layer of silicone rubber acts as a spacer between those boards and an outer layer of Lycra that carries a metal contact above each copper contact. This arrangement allows 12 "tactile pixels" - or taxels - to be sensed per triangle. This taxel resolution is enough to recognise patterns such as a hand grasping the robot's arm. [...]
Peratech's answer is a stretchy, elastic material it calls quantum tunnelling composite (QTC). This comprises a polymer such as silicone rubber that is heavily loaded with spiky nickel nanoparticles. A voltage is applied across the skin, and when it is pressed, the distance between the nanoparticles within the polymer diminishes, which results in electrons flowing, or "tunnelling", from one nanoparticle spike to the next in the area being touched.
Robots with skin enter our touchy-feely world
Current Music: Adult -- Skinlike (Equation Mix) ♬