Design and modeling of a piezoelectric actuator for minimally invasive surgery

A small-scale piezoelectric actuator has been designed for use in minimally invasive surgery. The actuator is designed to actuate a compliant suture needle grasper as part of a telerobotic surgical system. The actuator consists of a single piezoceramic stack and a slider-crank mechanism which acts as a mechanical stroke amplifier. The main focus of this paper is on the design of the actuator and fabrication and test of a prototype as a proof of concept. The design and fabrication of the prototype actuator is discussed as well as experimental results measuring its performance. A quasi-static model of the actuator which predicts the mechanical amplification and force response is also discussed. Results from laboratory bench-top experiments are presented, and the actuator together with the compliant gripper are shown to grasp and hold a standard suture needle.