On the robust nonlinear motion position and force control of flexible joints robot manipulators (Q1307612)

The authors present the design of a robust nonlinear position and force controller for a two-link robotic manipulator with flexible joints that interacts with a rigid environment. The design of the controller is based on the concept of feedback linearization using sliding mode techniques and linear quadratic estimation methods. The proposed controller modifies the feedback linearizing control law by adding a switching action to compensate for errors due to parametric uncertainties and to guarantee the desired tracking performance. An experimental study is described where a mechanical arm that is a two-link modular direct drive manipulator with flexible joints using helical torsion springs is combined with a real time controller. Both experimental and simulation results show the value of this control approach even with the presence of parameter uncertainty in the dynamic model.