Mars Entry Trajectory Tracking Using Constrained Predictive Control

Aiming at tracking the vehicle’s entry optimized trajectory for Mars Landing,a new method based on constrained predictive control is proposed.The vehicle’s nonlinear dynamics,the initial state uncertainties, saturation limit of the control input and the parameter perturbation are taken into consideration synthetically.A constrained predictive control (CPC) is developed which consists of a linearized step-response predictive model,feedback correction and constrained rolling optimization.The simulation results indicate that:constrained predictive control has a more accurate guidance command tracking performance compared with the PID method,therefore its radius error at the parachute deploying point is far smaller than that of the PID method;a smooth control curve canbe obtained under the saturation constraint of the control input.