Abstract：Traditional robotic sliding mode control is mostly based on linear PD sliding mode and uniform reaching law. Based on exponentially reaching law,a new PD+PID sliding mode control is proposed in this paper. Simulation has been implemented and the results are compared with PD sliding mode,PID sliding mode,PID+PD sliding mode respectively. Sigmoidal saturation functions are also exploited as an alternative to the commonly used saturation functions and comparative results are given. To decrease chattering,two measures are proposed,and good results have been achieved.
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