Motivated by new aerospace applications, the condition of minimum‐energy achieving high accuracy of both terminal orbital injection and attitude angle is required for better navigation and observation. The stability of guidance command also needs to be improved considering the control system. In this article, an optimal guidance algorithm with an advanced numerical method of spacecrafts is proposed. In order to ensure the continuity of the attitude angle and its terminal constraints, the thrust vector is treated as the state variable in the optimal control problems, and the rate of attitude angle change is regarded as the control variable. Then the optimal ascent problem of spacecrafts based on a nondimensional dynamical model is derived in detail, including performance index considering energy consumption, optimal conditions, and terminal conditions. To improve the computational efficiency of optimal ascent problems, a numerical method and a solution strategy are proposed. Simulation results show that the terminal attitude angle error of proposed method is much less than that of the traditional guidance method, and the continuity and stability of the guidance command is also better, which demonstrates the high accuracy and strong adaptability of the guidance algorithm developed in this article.

中文翻译：

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最优控制理论的航天器末端姿态约束改进制导算法

在新的航空航天应用的推动下，为实现更好的导航和观察，要求达到最低能量的条件才能实现最终轨道注入和姿态角的高精度。考虑到控制系统，制导指令的稳定性也需要提高。本文提出了一种具有先进数值方法的航天器最优制导算法。为了保证姿态角及其终端约束的连续性，将推力矢量作为最优控制问题中的状态变量，将姿态角变化率作为控制变量。然后详细推导了基于无量纲动力学模型的航天器最优上升问题，包括考虑能耗，最佳条件的性能指标，和终端条件。为了提高最优上升问题的计算效率，提出了一种数值方法和求解策略。仿真结果表明，所提方法的终端姿态角误差远小于传统制导方法，并且制导命令的连续性和稳定性也较好，证明了该方法的准确性和较强的适应性。本文。