Design and control of a new electrostrictive polymer based continuum actuator for endoscopic robot

Abstract

Minimally Invasive Surgery (MIS) consists of the insertion of a flexible endoscope into the patient body through natural orifices. Over the past few decades, the growing interest in microelectromechanical systems (MEMS) has paved the way for ubiquitous miniaturized integrated sensors and actuators in medical endoscopy. Nowadays, recent advances in materials have opened a promising way to fulfill the surgical requirements and size constraint for the development of smart continuum structures. Among smart materials, electroactive polymers (EAPs) exhibit exceptionally large, fast, repeatable, and reversible motions while perfectly meeting the requirements of micro-integration. However the high applied voltage required for the actuation is not compatible with in vivo medical application. To overcome these issues, a multilayered concept has been proposed. In this work a relaxor ferroelectric electrostrictive polymer is studied for its large electromechanical strain. A wide range of parameters involved in the active material has led us to the development of a finite element model on Abaqus to guide the experimental development. Then, to control this smart endoscopic robot a kinematic and a dynamic models have been built. To test and validate these models a Co-simulation procedure has been developed. This procedure coupled Abaqus and Matlab-Simulink allowing testing proposed control algorithms.