Constrained state feedback pole placement of coupled lateral plant dynamics of RLV during the reentry phase

Abstract

Stability and dynamic behaviour of a linear multivariable system mainly depend on the pole locations of the plant in the complex s plane. For general linear time-invariant multi-input multi-output (MIMO) systems, static (constant gain) output feedback pole-placement is an open nondeterministic polynomial time (NP) hard problem. This problem has attracted much attention from the control community for the last four decades. Even today, the general problem has not been solved analytically because of its highly nonlinear nature. In this paper, we have addressed the issue of finding gains without using the procedure of sequential loop closure. We have proposed an iterative numerical algorithm to solve the pole placement problem with a minimum number of feedback gains. The proposed method is used to compute the state feedback gain matrix for coupled yaw-roll dynamics of a typical reusable launch vehicle (RLV) during the reentry phase.