一种火星进入段在线脱敏轨迹设计方法

为降低轨迹求解难度，提升脱敏制导的适应性，针对火星进入段提出一种在线脱敏轨迹设计方法.首先，采用预测的末端航程偏差和状态敏感度作为性能指标，利用该指标为倾侧角凸函数的特性将最优求解问题转换为简单的动态寻优过程；其次，结合任务要求和估计的进入点状态，通过迭代得到同时满足航程和横程要求的三自由度脱敏轨迹.仿真表明该方法可达到与现有脱敏设计相近的末端状态精度.

An Online Desensitized Trajectory Design Method for Mars Entry Guidance

To reduce the difficulties in trajectory optimization and improve the adaptability of desensitization guidance, a novel online desensitized trajectory design method is proposed for Mars entry. The weighted value of predicted terminal sail error and state sensitivity are adopted as performance indexes, which are actually convex functions of bank angle. Taking use of this property, the original optimization problem is converted into a simple dynamic optimizing process. Then, according to the mission requirement and estimated entry state, a three degree of freedom desensitized trajectory that simultaneously satisfies the requirement for range and cross range can be found via iteration process