Control of Rotary Flexible Joint by Two-surface Discrete Sliding Mode Control based on Approach Angle Reaching Law

Abstract – In this paper a discrete time sliding mode controller with two surfaces is used to control rotary flexible joint and to reduce the vibration of the arm. Here, approach angle reaching law is used to take the trajectory to the surfaces. The advantage of using a two surface sliding mode control is that the system trajectory is brought to the first surface with maximum velocity thereby shortening the reaching phase. The scheme assures robustness, fast transients with reduced chattering when compared to single surface sliding mode.