AN EMPIRICAL APPROACH TO MODELING PRESSURE BUILDING-UP PROCESS INSIDE PNEUMATIC ARTIFICIAL MUSCLE ACTUATORS

Abstract

Pneumatic muscle actuators (PMAs) have great potential in robotics and industrial applications. However, high non-linearities hamper the further applications in accurate performances. Pressure built-up process is highly non-linear due to non-linear elasticity of rubber tube of the PMA and air driving mode, and brings great challenges in approximation. This paper analyzes the experimental responses of charging and discharging process, respectively, and employs second-order linear system to model the charging and discharging dynamics inside PMA. Experiments are performed to validate the effectiveness of the established models and comparison between simulated curves and experimental data indicates that the built-up models can capture the dynamics of pressure changing processes inside PMA.