Abstract

This study entailed the derivation of an inverse airflow dynamics model that causes pneumatic transmission delay due to the long air tube in pneumatic artificial muscle (PAM) control. The inverse model of the derived airflow dynamics was used in designing a feedforward pressure control command for the proportional pressure control valve. We also modulated the feedback command based on the proposed pressure control for precise force tracking performance. The proposed methods were validated by varying the tube lengths in the pressure tracking task and force tracking task. The tracking tasks with the sinusoidal desired profile of 2.5 Hz were successfully achieved using the proposed method. The results indicate that the proposed method can compensate for the delay due to the airflow dynamics in the long air tube and improve the control performance.