基于多目标规划的交会对接推力器指令分配方法

将由控制律得到的控制量转化为推力器控制指令的过程称为推力器指令分配。由于交会对接涉及的推力器配置复杂,且对追踪航天器姿轨控精度的要求很高,因此其推力器指令分配问题十分重要。本文针对该问题,分析了基于线性规划的指令分配方法存在的不足,提出了将推力器指令分配问题转化为非线性多目标规划问题,并应用分枝定界法进行寻优的新方法。新方法可以在指令分配的误差和燃料消耗之间进行折衷,并且考虑了推力器最小开机时间的限制。仿真结果验证了新方法的有效性。

A Method of Command Distributing of Thrusters in Rendezvous and Docking Based on Multi-objective Programming

Transforming the output of controllers into the commands executed by thrusters is called command distributing of thrusters. The configuration of thrusters for rendezvous and docking is very complex.And high control accuracy of chaser's attitude and orbit is needed.Therefore the problem of command distributing of thrusters is very significant.In order to solve this problem,firstly the disadvantage of the method of command distributing of thrusters based on linear programming is analyzed.Secondly a new method is presented.This new method transforms the problem of command distributing of thrusters into a problem of nonlinear multi-objective programming,and then seeks the optimal solution by the branch-and-bound method.The new method can make a tradeoff between the error of command distributing of thrusters and propellant consumption.And the minimum firing duration of thrusters is also taken into account.At last,simulation results are given in order to demonstrate the effectiveness of the new method.