Application of time-delay-control in variable structure motion control systems

A new simple sliding mode controller for the motion control systems is proposed to avoid the problems related to chattering. The proposed control is based on the time delay estimation used in the time-delay-control (TDC) method. By introducing the concept of time delay estimation into the sliding mode control, the difficulty of the stability analysis of TDC may be resolved. It has been shown that the switching component of the proposed control is not determined by the magnitude of the system´s uncertainty but by its change during specified time delay. That leads to much smaller magnitude of the switching component in comparison with other sliding mode controllers. For the proposed control scheme the sliding mode reaching and existence conditions for a class of systems like a robotic manipulator are presented. The experimental examples are shown to confirm the validity of the proposed controller.