中文摘要：

本文针对三自由度翼伞系统威胁规避归航轨迹优化问题进行了研究,采用了控制变量参数化和精确罚函数优化算法对翼伞系统的最优控制问题进行了数值求解。该方法将控制量转化为参数,将路径约束与控制约束问题转化为无约束问题进行求解。与粒子群算法（PSO）的计算结果进行了比较,仿真结果表明：本文设计的控制方法效果良好,所需控制能耗低,距离偏差与方向偏差均满足实际需求,有效地提高了翼伞系统的着陆精度与生存能力,验证了该优化算法的可行性与高效性。

英文摘要：

In this paper,we discuss the optimization on the homing trajectory of a three-degree-of-freedom parafoil system,considering threat avoidance. We use the control parameterization and exact penalty function methods to obtain a numerical solution to the optimal control problem of a parafoil system. This method can convert control decision variables into parameters,and the path and control restriction problem into a non-restriction problem. We then compared the control algorithm with particle swarm optimization（ PSO）. The simulation results show that the performance of the control algorithm is good,the control energy consumption is low,and the deviations of distance and direction satisfy requirements. In addition,this method can effectively improve landing precision and the terrain-avoiding ability of the parafoil system. Thus,the feasibility and effectiveness of the proposed optimization algorithm is verified.