Experimental study of model-free vibration control based on a virtual controlled object considering parameter uncertainty of actuator

This study experimentally verifies robustness of a model-free vibration controller based on a virtual controlled object (VCO) considering parametric uncertainty of actuator. A proof-mass actuator, which can be modeled as a single-degree-of-freedom (SDOF) system, is used. A VCO, which is defined as an SDOF structure, is introduced between a real controlled object and the actuator model. The parameters of the VCO are determined so as to achieve model-free vibration control. A state equation to derive the model-free controller is constructed using the two-degree-of-freedom (2DOF) structure composed of the actuator model and the VCO. The parametric uncertainty of the actuator is quantitatively characterized in the 2DOF structure. The mixed H 2 / H ∞ control theory is used to design a model-free controller. The vibration suppression performance and robustness to the actuator uncertainty of the proposed method are validated by experiments. Simulation studies are also conducted to enhance the validity of the experimental results. As a result, the proposed damping method exhibits good damping performance and strong robustness to the actuator uncertainty and characteristic changes in controlled object.