航天器姿态控制的区间参数化方法

Interval Parameterization Method for Spacecraft Attitude Control

考虑一类航天器姿态最优控制问题,通过控制参数化的方法和约束转录的方法,将航天器姿态最优控制问题转化为最优参数选择问题.提出一种新的区间时间变换方法用于解决最优参数选择问题的切换时间点的计算问题.将时间切换点按顺序分为一系列子集,将每个集合的所在的时域宽度作为决策变量进行优化,每个子集内的切换时间点将会随着此决策变量线性变化.由此,控制值将分布在数个稠密或稀疏的区间内,而不是由均分的分段常值函数表示.相比于全时间节点优化技术,此方法有效的降低了需要计算的决策变量的数量,增加了算法的执行效率.

The spacecraft attitude optimal control problem is considered,and the optimal attitude control problem is transformed into an optimal parameter selection problem by means of control parameterization and constrained transcription.A new interval time transformation method is proposed to solve the calculation of switching time for optimal parameter selection problem.The switching time is divided into a series of subsets in order,and the time domain width of each set is optimized as the decision variable.The switching time points in each subset change linearly with the decision variable.Thus,the control values distribute in several dense or sparse intervals,instead of being represented by evenly divided piecewise constant functions.Compared with the full-time node optimization technique,this method effectively reduces the number of calculated decision variables and increases the execution efficiency of the algorithm.