Control of Compliant Joint Based on Magneto-rheological Fluid Coupling Transmission

Abstract

Magneto-rheological fluid has controllable rheological properties, as a result, the compliant joint of robots based on it has active variable stiffness transmission characteristics. Magneto-rheological compliant joint coupler is a key transmission component of the compliant joint of robots which designed based on magneto-rheological fluid shear transmission mode. Due to inherent nonlinear characteristics such as time-varying parameters, hysteresis and magnetization saturation, it is of great difficulties to establish an accurate mathematical model. A magneto-rheological compliant joint coupler torque control method based on fuzzy adaptive PID algorithm was proposed, a smooth joint coupler drive system experimental platform was established, a torque control interface of compliant joint coupler transmission system designed on NI LabVIEW was developed, the torque control experiments based on fuzzy adaptive PID algorithm and conventional PID algorithm were done respectively. The consequence reveals that compared with the conventional PID algorithm, the conventional PID algorithm has more excellent velocity of response trait and more stabilized peculiarity, and the control effect also shows better.