Design of a SMA actuated 2-DoF tactile device for displaying tangential skin displacement

Tangential skin displacement at the fingertip is an effective means of communicating direction or displaying static friction in haptic application. A tactile device capable of stretching the skin of the fingerpad can be mounted directly on the fingertip or embedded in haptic interfaces and hand-held devices. In both cases low weight and small dimensions are important requirements. We have developed a miniaturized tactile device capable of displaying tangential skin displacement in two directions. The actuation for the device is realized by SMA wires, in order to reduce bulk and weight, and the displacements are measured by optical sensors. The performance of the device has been verified experimentally.