Robust Controller of LSS by utilising Symmetry

Abstract

For general mechanical systems with collocated sensors and actuators, it is known effective to use a symmetric controller. The symmetric controller guarantees robust stability of the closed loop system by virtue of its structure having positive definite or positive semi definite symmetric coefficient matrices. This paper proposes an optimal design method of the symmetric controller in the sense of H_∞ norm. In the synthesis, the optimal controller is obtained by solving the linear matrix inequality reduced from the bounded real lemma. This method has advantage over other robust control technique in its structural simplicity. Finally, we apply the design method to the actual large space structure model.