摘要
针对6自由度的小行星动力着陆多约束轨迹优化问题,提出了一种基于序列凸优化的小行星着陆轨迹优化算法。首先采用多面体引力场模型计算小行星的引力场,其可用于描述任意形状的小行星引力场,且比质点群法和球谐函数展开法等方法计算精度更高。为了在凸约束下解决小行星着陆过程燃料消耗最优问题,通过对探测器动力学模型及其约束进行线性化和离散化,将原来的非凸连续时间优化问题转化为凸化的子问题,即二阶锥规划问题(SOCP);然后引入了虚拟控制项和信赖域,以增强算法的鲁棒性。通过在形状不规则小行星上的着陆模拟,验证了所提出算法的有效性,仿真结果满足各项约束条件,可实现高精度着陆和燃料消耗最优的目标。
Aiming at the multi-constraint trajectory optimization problem of 6-degrees-of-freedom(6-DOF)dynamic asteroid landing,an optimization algorithm of asteroid landing trajectory based on sequence convex optimization is proposed.Firstly,the polyhedron gravity field,a suitable approach for describing the gravitational field of irregular-shaped asteroid,is adopted to calculate the gravitational field of the asteroid,which can be used to describe the gravitational field of the asteroid of any shape,and the calculation accuracy is higher than that of the spherical harmonic gravity field and the particle group gravity field.In order to solve the problem of optimal fuel consumption during asteroid landing under convex constraints,the initial non-convex continuous-time optimization problem is transformed into convex sub-problem,namely the second-order cone programming problem(SOCP),by linearizing and discretization of the dynamics model and constraints.Virtual control terms and trust domains are then introduced to enhance the robustness of the algorithm.The effectiveness of the proposed algorithm is demonstrated by the simulation of landing on an irregular-shaped asteroid,and the results meet all the constraints,achieving the goals of high-precision landing and optimal fuel consumption.
作者
初彦峰
穆荣军
梁浩
崔乃刚
CHU Yanfeng;MU Rongjun;LIANG Hao;CUI Naigang(School of Astronautics,Harbin Institute of Technology,Harbin 150001,China;Beijing Institute of Aerospace Systems Engineering,Beijing 100076,China)
出处
《宇航学报》
EI
CAS
CSCD
北大核心
2024年第3期341-351,共11页
Journal of Astronautics
基金
国家载人航天专项第四批预研项目(18123060201)。
关键词
小行星着陆
多面体引力场模型
6自由度
序列凸优化
Asteroid landing
Polyhedron gravitation model
Six-degree-of-freedom(6-DOF)
Sequential convex optimization
