A Closed Loop Sub-Optimal Guidance Design for Sub-Orbital Flying Systems

In this paper, a novel closed loop guidance method is provided for sub-orbital systems. The proposed method can be used in the first phase of a flying vehicle system that flies in atmosphere. In this method, sub-optimal integrated solution of control and guidance in closed-loop is developed. This Sub-optimal guidance technique has been named Model Predictive Static Programming (MPSP) that based on nonlinear optimal control theory and derived from combined philosophies of Model Predictive Control and Approximate Dynamic Programming solves a class of finite horizon optimal control problems with terminal constraints. Also because sensitivity matrices that are necessary for obtaining this solution can be computed recursively, this technique is computationally efficient and is appropriate for online implementation. In this paper, the system’s dynamic equations are modeled in the presence of aerodynamic forces and moment and the dynamic servo-mechanism effect is also assumed in the equations. Furthermore, by simultaneously considering the guidance and control loops, an integrated solution of the guidance and control system is proposed by three-degree of freedom spherical earth simulation model. Result show that proposed closed-loop guidance is able to remove modeling errors by flight data update and guide flying vehicle to the desired point.