Development of a light-weight robot end-effector using polymeric piezoelectric bimorph

The development of a lightweight piezoelectric end-effector (multifinger type) for robotic applications is reported. The fundamental configuration of each finger is a simple piezoelectric bimorph structure made of a piezoelectric polyvinylidene fluoride material. Injection of a controlled high voltage into the finger can induce a deformation in a prescribed direction. Depending on the applied voltage, the effector can hold an object from outside or inside. The theoretical predictions are verified by the experimental and finite-element simulation results. This end effector is designed for lightweight objects such as electronic chips, and for high-precision (or even micro-precision) operation. Gripping force can always be enhanced by injecting higher voltage. Coordinating the applied voltage in two fingers can also compensate the position offset if misalignment exists in the setup