Tactile display MEMS device with SU8 micro-pin and spring on SMA film actuator array

We propose a 5x5 arrayed MEMS planar tactile display device (1 mm pitch) consists of SMA thick film actuator array and photo-lithographed SU8 micromechanism of bias spring, micro-pin, and cap array. The SU8 bias spring was designed so that the tactile display can generate 20 μm displacement and 5 mN force when it is combined with the SMA actuator in static motion. The amplitude of the tactile display decreased with increasing driving frequency when it was driven by pulse voltage with 50 % duty ratio. However, the device was able to generate amplitude larger than 10 μm, sufficient for vibratory stimulation to human skin, at 30 Hz with low duty ratio.