A Comparison of Feedback Linearization and Singular Perturbation Techniques for the Control of Flexible Joint Robots

Analytical and experimental results comparing feedback linearization and singular perturbation control techniques for flexible joint robots are presented. The feedback linearization approach results in a globally decoupled linear system which can be controlled using techniques of linear system theory. The singular perturbation approach exploits a natural time-scale separation that results from large joint stiffness to compute a composite control law to damp the joint oscillations while exploiting the desirable properties of rigid robot dynamics.