Adaptive Regulation in Switched Bimodal Systems: An Experimental Evaluation

This paper presents experimental results on the adaptive exact output regulation in a switched bimodal mechanical system subject to unknown sinusoidal exogenous inputs representing reference or disturbance signals. The adaptive regulator design exploits the Q parameterization of regulators for the switched system, and where the Q parameter is tuned online to yield the desired regulator. The proposed adaptive regulator is evaluated on an experimental setup motivated by the flying height regulation problem in hard disk drives. In the experimental setup, the tip of a flexible beam is supposed to maintain a constant separation with respect to a surface with an unknown profile, while also being subject to an unknown disturbance force. The system exhibits a switching behaviour depending on whether contact takes place between the surface to be tracked and the tip of the beam. The experimental results successfully demonstrate the effectiveness of the proposed approach in achieving exact output regulation against unknown sinusoidal exogenous inputs and in the presence of switching in the system dynamics.