A Two-axis Bimorph Piezoelectric Actuator for Pressure and Slippage Force Presentation

We are studying a two-axis micro-actuator to enhance the presentation reality of a tactile display that is capable of presenting pressure distribution and shearing force. We develop two types of actuators; Actuator A is composed of sequentially connected x- and y-directional actuators; each actuator is comprised of bimorph piezoelectric actuators. The x- and y-directional actuators are independently controlled by changing the applied voltage to position a probe that is attached to the tip of a two-axis actuator. The maximum displacement and force generated by the x-directional actuator are 1.1 mm and 0.03 N, respectively. Those generated by y-directional actuator are 1.0 mm and 0.06 N, respectively. Actuator B is composed of two bimorph actuators making an angle, two small links and three joints. At the present, we confirm that the actuator can move along x and y-axes of two-dimensional coordinate. Finally, since relationship between applied voltage and displacement caused by the voltage shows a hysteresis loop in the bimorph actuator used as components of the two-axis actuator, we produce a control system for the two-axial actuator based on a multi-layered artificial neural network to compensate the hysteresis