为使小推力发动机航天器在航行中实现轨道快速机动并有效节省燃料,提出了基于拟谱法的航天器轨道转移轨迹优化方法.采用改进的赤道轨道根数,基于高斯动力学方程建立了航天器轨道转移过程的数学模型,克服了经典轨道根数当偏心率为0,或者轨道倾角为0°或90°时的奇异问题,给出了航天器轨道转移燃料最优性能指标函数以及终端约束和路径约束条件；采用拟谱法,将原始的连续最优控制问题转化为非线性规划问题；利用SNOPT(sparse nonlinear optimizer)算法求解最优轨迹,并提出了具体设计步骤和方法.仿真结果表明:与fmincon优化方法相比,发动机最大推力为20N时,本文的优化方法寻优时间减少61％,节省燃料18％.%In order to achieve the rapid maneuver and effective fuel saving of the spacecraft with finite thrust in flight,trajectory planning based on psedospectral method was studied.Orbit transfer was modeled mathematically with Gauss dynamics equations by using improved equatorial orbital elements.The model could overcome the singularity problems when the orbital eccentricity was 0° or the orbit inclination was 0° or 90°.Then,the fuel optimal performance index function,terminal constraint,and path constraint conditions were given; and the original continuous optimization problem was converted to the equivalent finite nonlinear planning problem by psedospectral method.Finally,the sparse nonlinear optimizer (SNOPT) algorithm was utilized to solve the trajectory planning problem,and the specific design steps and methods were given.Compared with the optimization method using fmincon function,the proposed method can reduce the optimization time by 61％ and save the fuel consumption by 18％ when the maximum thrust is 20 N.
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