Discrete time output feedback sliding mode control algorithm for chattering reduction and elimination

This paper presents discrete time sliding mode control which uses multirate output feedback and power rate reaching law. The method proposed here uses only output samples and past control input for switching function evaluation and sliding mode control. The discrete time version of power rate reaching law has been obtained and then output samples based algorithm has been developed. It has been shown that it is possible to reduce chattering by suitably choosing the reaching law parameters. It has also been demonstrated that it is possible to avoid chattering completely for special case of controller parameters using only output information.The simulation study carried out on numerical example reveals effectiveness of the proposed algorithm.