Analysis of a Soft Haptic Device with Integrated Tactile Sensor and Actuator for Optimal Design

This paper presents the analysis of a soft haptic device comprising of tightly integrated touch sensor and actuator (SensAct). The integrated SensAct device comprises a piezoresistive touch sensor fabricated on the top of a flexible micro coil based electromagnetic actuator. The effect of the joule heating from the coil was studied using the fabricated device and the design parameters such as magnetic force, actuator displacement for different currents were determined through a finite element simulation. The joule heating is seen to occur only for current values from ~90mA and above and below this value, the actuator/sensor pair works well. From the steady-state analysis using the finite element simulation, the possible thickness-mode displacement was observed to be around ~200μm with ~20 mN magnetic force produced by the coil. These results show the potential of SensAct devices for vibrotactile feedback and with programmable thickness mode movements they could lead to intelligent interactive surfaces.