Approach of robust pole assignment based on normal matrix

The robust pole assignment approach for linear time-invariant multivariable system is investigated based on the properties of normal matrix. By the combination of frequency-domain and time-domain normal matrix control methods, the normal pole assignment approach proposed can provide H_∞. robust control law to the linear time-variant system. And the solving of matrix equation for orthogonal matrix is transformed into a searching process, to avoid the failure in solving and provide more flexibility. The effectiveness is demonstrated by a design example for spacecraft attitude control.