System Identification of Pneumatic Artificial Muscles(PAMs) and One-DoF Base Joint Mechanism

Abstract

Soft actuators are one of the alternatives to general rigid motors. The goal of soft things is for human-interaction that rigid things can not. Among them, PAM, which is a pneumatic artificial muscle actuator, shows similar characteristics to artificial muscles and is seen as a good substitute for stability, lightness and good performance. Various shapes and characteristics of actuators using air pressure have been studied. I made a PAM with the most basic shape and tried to carry out an experiment to understand characteristics of the PAM. In order to control PAM well, it is necessary to grasp the model well, and it is difficult to model air as a compressible gas. The original pneumatic pressure is basically nonlinear, but it is assumed that it is a linear system for easy access first. The relationship between force and pressure was acquired and verified using bode plot. Also, for application, I tried to implement a 1 degree of freedom base joint using the PAM actuators.