倾转旋翼无人机最优过渡倾转角曲线

建立了典型三点式倾转旋翼无人机动力学模型，针对过渡过程，开展最优倾转角曲线研究以减小横侧控制耦合对纵向运动影响和过渡过程能耗。基于倾转角曲线对过渡过程的影响分析，提出了改进运动剖面算法对倾转角曲线进行参数化设计；并提出两阶段优化方案来对参数进行优化。第1阶段，综合考虑横侧控制耦合度最低和过渡过程能耗最小目标，以曲线参数为优化变量，构建了最优倾转角问题模型，采用遗传算法进行优化求解。第2阶段，引入舵机动力学模型，考虑过渡时间和系统超调进一步优化以减小结束阶段的超调。与2种现有典型倾转角曲线对比结果表明:给定过渡时间，设计的最优倾转角曲线有效地降低横向控制耦合程度和过渡过程的能耗，且减小结束时超调。 

Optimal transition tilt angle curve of tiltrotor UAV

A dynamic model of a typical tri-tiltrotor UAV was established. The optimal tilt angle curve in the transition process was studied to reduce the influence of lateral coupling on longitudinal motion, and energy consumption. Based on the analysis of the influence of the tilt angle curve on the transition process, a improved motion profile algorithm was proposed to parameterize the tilt angle curve. A two-phase optimization scheme was proposed to optimize parameters. In the first phase, the minimum coupling degree of lateral control and the minimum energy consumption of the transition process are considered. The optimal tilt angle problem model was constructed by using the curve parameters as the optimization variables.The optimal tilt angle problem was solved by genetic algorithm. In the second phase, a servo dynamics model was introduced for further optimization to reduce the overshoot in the end-stage considering transition time and system overshoot. The results of comparison with the three existing typical tilt angle curves show that, in given transition time, the proposed optimal tilt angle curve effectively reduces the lateral control coupling degree and the energy consumption during the transition process, and reduces the overshoot at the end of the transition.