Anti-windup weighted pseudo-inverse control allocation method based on stealthy characteristic

The fixed weighted pseudo-inverse (FWPI) with explicit control law can easily lead to position saturation of the control surfaces in over-actuated flight control system, which may introduce much more unexpected radar cross section (RCS) to the aircraft. In this paper, a varying weighted pseudo-inverse (VWPI) control allocation method is proposed with the target of reducing effectors stealthy objective. The RCS of each control surface in different deflection angle is calculated by FEKO. Then, the RCS function respecting to deflection angles is obtained by polynomial fitting in Matlab. To minimize the stealthy objective produced by control surface deflections, the WPI mathematic model with the calculated stealthy characteristic data is established. By applying the Lyapunov stability theorem, the VWPI optimization model is designed and deduced in linear matrix inequality. The simulation on an over-actuated aircraft shows that the VWPI scheme can make the saturated control surface anti-windup automatically by varying the weight coefficients matrix, meanwhile, gain better stealthy reducing performance compared with FWPI.