火星探测器进入段预测校正制导方法

根据美国宇航局的计划,未来火星探测任务的要求是能确保在高精度和高海拔的火星表面着陆,而进入段所使用的制导方法是探测器能够精确着陆的关键。文章首先介绍了两种进入段制导算法——标称轨迹算法和预测校正算法,通过比较得出预测校正算法对于初始扰动的敏感性较低,但需要有较高的在线计算能力;其次,文章对于预测校正中的横向控制,纵向控制算法和航向调整算法进行了详细介绍,同时提出一种通过增加检测点的改进预测校正算法;最后对算法进行软件仿真,仿真结果表明:这种进入段预测校正制导算法在有很高不确定性的情况下仍然能体现出可靠性和鲁棒性。

Mars Entry Guidance Based on Predicted Corrector Algorithm

This paper describes the development and evaluation of the common numerical predicted corrector algorithm and gives an improved algorithm for the Mars entry guidance. First, it introduces two guidance strategies:tracking the reference trajectory and predicted corrector algorithm, finding that the common predicted corrector algorithm can be less sensitive to initial dispersions, but needs fast on-board computation. Second, the downrange algorithm, lateral control logic and heading alignment are described in details, which are provided to improve the horizontal accuracy of the vehicles. Furthermore, the segmented guidance predicted corrector algorithm is used to shorten the on-board computational time. Simulation results show that this entry guidance algorithm demonstrates reliable and robust performance in situations with high uncertainties.