Application and Comparison of passivity-Based and integrator backstepping Control Methods for trajectory Tracking of Rigid-Link robot manipulators Incorporating Motor Dynamics

In this paper, dynamic equations of motion of a rigid-link non-redundant n-DOF robot manipulator consisting of mechanical arms, all with revolute joints and electrical actuators are considered and application of passivity-based and integrator backstepping techniques for trajectory tracking of the robot in presence of disturbance, friction and uncertainty is studied. One of the main advantages of the backstepping control techniques is that they impose desired properties of stability, initially by fixing the candidate Lyapunov functions, then by calculating the storage functions, stabilizing functions and feedback control laws in a recursive way. Simulation results of applying these schemes show the ability of backstepping methods in trajectory tracking in presence of disturbance, friction and parameter uncertainty. Comparison of simulation results of the two backstepping methods shows that passivity based with respect to integrator based method has more smooth control commands and better trajectory tracking by using passivity properties of the robot and by using some weighting matrices in its algorithm.