MEMS Tactile Display with Hydraulic Displacement Amplification Mechanism

Tactile displays mechanically stimulate tactile receptors on a finger pad. They require a micro-actuator array capable of generating displacement greater than 100 mum. We propose a MEMS-based tactile display with hydraulic displacement amplification mechanisms (HDAM). HDAM contains micro-cavities that have different cross-sectional areas between at the contact and the drive parts and encapsulate incompressive glycerin with largely-deformable thin PDMS (polydimethylsiloxane) membranes. Displacement applied to the drive part is amplified at the contact part associated with the ratio of cross-sectional areas of the drive to the contact parts. HDAM was fabricated and achieved a seven-fold of amplification. We successfully demonstrated rewritable Braille codes.