考虑火箭约束的深空探测弹轨道拼接模型

Ballistic-Orbit Splicing Model of Deep Space Exploration Considering Launch Constraints

针对深空探测任务轨迹规划中对于运载火箭弹道约束考虑不足、弹轨道拼接设计效率低的现状,建立了考虑运载火箭射向和末级滑行时间约束的弹轨道拼接计算模型,在无引力摄动假设下得到了任意深空出发速度条件下的运载火箭射向和末级滑行时间计算公式。利用该模型分析了弹轨道可成功拼接的集合范围随深空出发速度、发射场地理位置、火箭射向和滑行时间约束范围的变化规律。提出深空出发"赤纬-发射能量"(δ-C3)图方法,可在图上表示指定型号运载火箭深空发射能力可行域,结合深空轨道转移Pork-Chop图方法,可以快速判断该型运载火箭是否适用于特定深空发射任务。依据这一方法,提出了对我国未来深空探测运载火箭射向和末级滑行时间的能力需求。

Current research on trajectory optimization of deep space mission hardly takes launch constraints into consideration, thus resulting in low efficiency in ballistic-orbit splicing design. A calculation model of ballistic-orbit splicing is established considering launch vehicle’s launch azimuth and coasting time constraints. The calculation formula of launch vehicle’s launching azimuth and coasting time under an arbitrary deep space departure speed is obtained with zero gravitational perturbation assumption. Through this model, the variation pattern of splicing solution set under different deep space departure speed, launch site geographical position, rocket’s launching azimuth and coasting time constraints is analyzed. The δ-C3 map method is proposed to represent the feasible range of deep space launch capability of specified launch vehicle. Combined with Pork-Chop map, this method can be easily used to determine whether one type of launch vehicle is suitable for specific deep-space launch mission. According to this method, the design specifications on launching azimuth and coasting time of China’s future launch vehicles suitable for deep space missions are proposed.