Experimental Comparison of Model-Free Vibration Control Based on Virtual Controlled Object and Model-Based Control: Robustness to Characteristic Changes in Actual Controlled Object Available to Purchase

Model-free active vibration control based on a virtual controlled object (VCO) has attracted a great deal of attention due to its simplicity. This study experimentally compares VCO-based model-free vibration control with model-based control in terms of the robustness to characteristic changes in an actual controlled object. The VCO is designed so as to achieve model-free vibration suppression in the designated frequency band. A state equation for designing a model-free vibration controller is constructed using only the actuator model and the VCO. The VCO-based model-free controller is designed based on the mixed H₂/H_∞ synthesis for the state equation. The model-based mixed H₂/H_∞ controller is designed based on the mathematical model of a both ends supported plate (BESP). The VCO-based and model-based controllers are tuned through vibration control experiment so that both controllers provide the same vibration reduction effects for the BESP. Then these controllers are applied to a vibration control experiment for a cantilever plate which is totally different from the BESP. As a result, the VCO-controller exhibits a good vibration suppression for the cantilever while the model-based one totally fails, revealing the advantage of the VCO-approach over the model-based strategy in the viewpoint of the robustness.