Output-feedback global stabilization of a nonlinear benchmark system using a saturated passivity-based controller

We address the problem of regulation of the benchmark rotational/translational proof mass actuator using a passivity-based controller. We show that a (relatively straightforward) modification of the output feedback saturated input controller proposed by the authors in a previous paper provides a simple and robust solution to the global asymptotic stabilization problem. The design technique is based on the practically appealing principles of energy shaping and damping injection. Computer simulations show that the performance is comparable, and in some respects better, than the one obtained with a far more complicated full-state unsaturated feedback controller.