Hybrid Optimal Control of Turret-Gun System

This paper presents a hybrid technique for optimal discrete-time control of a continuous-time nonlinear Turret-gun system. For effective design of this nonlinear Turret-gun system with multi-flexible modes, the linearized state-space representation of the nonlinear system is block-decoupled into a multi-time scale structure using the fast and stable matrix sign algorithm. Then, to enhance the robust stability and robust performance of the linearized system, an optimal regional-pole placement technique is applied to design a continuous-time optimal state-feedback control law with regional-pole constraints for individual block-decoupled subsystems. For digital control of the continuous-time Turret-gun system, the designed continuous-time state-feedback control law need to be converted into an equivalent discrete-time state-feedback control law, using the recently developed digital redesign technique. Since the states of the nonlinear Turret-gun system are inaccessible, a digital observer needs to be constructed for practical digital implementation of the digitally redesigned discrete-time state-feedback control law. In this paper, a reduced-order robust observer is established to reconstruct the true state of the nonlinear system. The designed results are demonstrated by the digital simulation of the controlled nonlinear model and the practical real-time control of the ATB-1000 testbed.