Voltage-based control of a flexible-joint electrically driven robot using backstepping approach

Among numerous torque-based control strategies proposed for flexible joint robot manipulators in the literature, a basic incorrect assumption is that torque can be exerted to manipulator link directly; so the actuator dynamics is not taken into account. In this paper a voltage-based technique for control of flexible joint robot manipulator actuated by brushed DC motor is proposed. The backstepping method is applied to cope with the difficulty introduced by the cascade structure and to find the control law to accomplish stabilization and tracking a desired trajectory. The suggested controller does not need the measurements of acceleration and jerk for feedback which are difficult to be measured. Simulation results are presented for a single link flexible-joint robot actuated by brushed DC motor to show the effectiveness of the designed controller in stabilization and trajectory tracking in presence of external disturbances.