A singular perturbation approach for tracking control of a parallel robot including motor dynamics

摘要

The tracking control problem of a parallel robot, including the electrical actuator dynamics, is addressed. The inverse dynamic model of the mechanical part is obtained using Lagrange and the geometric properties of the robot. For electrically actuated robots we design a nonlinear control law in the armatures' input voltages. The model obtained is in a standard form that allows the application of the singular perturbation method. To validate the proposed corrective controller, the passicity concept and the singular perturbation techniques are used. Computer simulations are performed on the model of a real electrically driven six degrees-of-freedom parallel robot where the friction model is incorporated. The results show the robustness of the proposed controller with a good trajectory tracking performance.