Design and Control of 6-DOF Robotic Manipulator Driven by Pneumatic Muscles and Motor

Abstract

A pneumatic-muscle actuator (PMA) is made of a unique material with fibers wrapped inside and metal fittings attached at each end. Because of reversible physical deformation, a PMA can produce linear motion during contraction and muscle expansion. We use a PMA and motors' hybrid drivers to implement a low-cost and safe robot manipulator with six degrees of freedom (6-DOF). Safety is achieved by applying a novel proxy-based sliding mode controller (NPSMC) and a linear extended state observer (LESO) on each joint of the 6-DOF robot manipulator. The NPSMC can compensate the six joints of the 6-DOF robot manipulator reaching Lyapunov stability, and we prove that their pathing errors converge to a neighborhood of zero. An experiment on all joints is conducted to verify the trajectory pathing precision and system safety for the 6-DOF robot manipulator. The experimental results show that under NPSMC compensation and the LESO estimate, the 6-DOF robot manipulator using the hybrid drivers satisfies both the pathing performance demands and safety control.