Predictive control-based optimal nonlinear reentry guidance law

This paper discusses a new nominal riding reentry guidance law design based on a nonlinear optimal predictive control approach. In this method, the error between the actual trajectory and the nominal trajectory is predicted, and a quadratic cost function of these predicted errors is minimised, resulting in an optimal feedback guidance law design. The guidance law thus obtained does not require linearisation of the equations of motion. A nominal trajectory is selected which satisfies the vehicle constraints and mission objectives. This nominal data is used with actual data to evaluate the guidance law. Numerical simulations have been carried out for a planar trajectory for a variety of initial condition errors and also for off nominal conditions and the results are presented.