Abstract:

An adaptive closed-loop guidance algorithm based on optimal feedback and rapid trajectory reconfiguration is studied and proposed for long-range orbit maneuver with finite thrust. Firstly principles and necessary conditions are presented to solve the optimal feedback control problem. Combining the characteristics of the dynamics model with the pseudospectral method, a computational efficiency refinement method with the reduced state parameters is proposed to improve the efficiency of trajectory optimization. The modified pseudospectral method is used for the successive rapid trajectory reconfiguration such that the open-loop optimal solution is fed back to the system to update the guidance commands in real-time. A control logic algorithm is introduced to improve the performance of the guidance algorithm. Considering many kinds of parameter uncertainties and external disturbances, lots of simulations of long-range space rendezvous are carried out successfully. The Simulation results indicate that the algorithm can not only provide an excellent optimal solution with high accuracy for practical mission, but can suppress uncertainties and external disturbances autonomously, adaptively and robustly.

Key words: Long-range orbit maneuver, Closed-loop guidance, Optimal feedback control, Modified pseudospectral method, Trajectory reconfiguration