Improving the Performance of an Actuator Control Scheme during Saturation

Abstract

This paper first introduces a new control scheme for a four fin missile actuation system. Exiting missile autopilot systems generally compute aileron, elevation, and rudder commands since these three variables dominantly influence the roll, pitch, and yaw motion of the vehicle. These commands are distributed to four fin deflection commands and fin controller actuates the fins to track the defection command. The performance of such control schemes can be significantly degraded when fin actuators are saturated due to certain physical constraints, such as voltage, current, or slew rate limit. This paper analytically proves that the proposed control scheme mitigates this problem, so it outperforms the conventional control scheme in the tracking performance if an actuator is saturated.Without any actuator saturation, the performance of the proposed scheme is also proved to be equivalent to that of a conventional actuator scheme. Numerical simulations verify the superiority of the proposed scheme and the theoretical analysis.