DC motor position control using sliding mode and disturbance estimator

A robust DC motor position control system is presented. The variable-structure system theory and practical considerations are used to design a robust linear controller incorporating a disturbance estimator for a second-order system. The control law is numerically implemented for position control. The performance of the control law is illustrated by simulation results, taking into account sampling time, computation time delay, the current regulator, and limitations on the control signal. The proposed algorithm is easy to design and implement. Simulation results have shown its robustness toward parameter variations, good dynamic response to a step in load torque, and a null static error