Independent modal control system design method via modal matrix estimation based on subspace method

In this paper, a design method for decoupling a multiple-degree-of-freedom (DOF) control system is proposed. In general, decoupling control systems have been designed by transforming the motion modes into the vibration modes using a modal matrix often utilized in the field of modal analysis. In the case where the physical parameters of the system are unknown, experimental modal analysis is currently the preferred method of estimating the modal matrix. This paper, however, proposes a new modal matrix estimation procedure based upon the state space model that has been identified by the subspace method. It then illustrates a design method for an independent modal control system using the estimated modal matrix. The effectiveness of the proposed method is examined through numerical simulations.