Tracking Control of Pneumatic Muscle Using Adaptive Passivity Based Control

Quantitative understanding of the mathematical model of pneumatic muscle (PM) is technically indispensable in control arrangement design for effective real-time execution. In this paper, a robust adaptive tracking method using passivity based control (PBC) techniques is developed and applied to a pneumatic muscle actuator (PMA) pulling a mass against gravity. Pneumatic actuators offer high performance at low cost, but their effective use is often hindered by external disturbances as a direct result of operating conditions. To enhance control performance and robustness for accurate trajectory tracking, we adopted a control objective to force the PM to track specified reference path in the presence of disturbances. A simulation is presented to analyse the behaviour of the proposed scheme. The simulation results verified that the model and the Adaptive Passivity Based Control (APBC) controller achieved required performance in tracking a demand trajectory within the particular accuracy.