摘要：This paper discusses the problem of design and optimization of low-energy transfer orbit with multi-body environment. A new integrative method is proposed to effectively solve the problem, in which the parameterized patched manifolds in CR3BP(circular restricted three-body problems), the shape-based method with multi-body environment, the homotopic method with multi-body environment, and the low-thrust capturing and descending algorithm with multi-body environment are all included. Firstly, the parameters describing the patched manifolds in CR3 BP are optimized until the least total absolute velocity increment has been got, including the employment of the shape-based method with multi-body environment. Secondly, the low-thrust control laws of the transfer orbit are optimized employing the homotopic method with multi-body environment that transfers the fuel optimization problem to an easier energy optimization problem. Thirdly, the low-thrust descending orbit around Mars is computed using the laws proposed in this paper. As a typical example, the Earth-Mars transfer orbit design is discussed. The results showed that the parameters describing the patched manifolds could be optimized by the DE(differential evolution) algorithm effectively; the homotopic method with multi-body environment could get the optimal value that meets the first order optimality conditions; and the low-thrust descending orbit could effectively be captured by Mars and finally become a circular parking orbit around it by the hypothesis control laws proposed in this paper. It shows that the final fuel cost is much less than the optimal transfer in the patched two-body problems. In conclusion, the method proposed in this paper could effectively solve the low-energy low-thrust optimal control problem in multi-body environment for the future deep space explorations.

摘要：选取某MW级风力发电机组为研究对象,设计了机组运动拓扑结构图,构建了风机整机的刚柔耦合多体动力学分析模型,并与气动力计算软件Aero Dyn和控制求解器通过接口力元实现联合仿真。模态分析计算得到了整机前6阶固有频率和模态振型,分析可知机组与关键转速区间激振频率不发生共振。动态仿真计算得到了3种不同工况下风机塔架迎风方向的位移、加速度动响应以及叶片三坐标方向的叶尖挠度,分析发现阵风期间塔架位移突然增大且瞬时波动剧烈;叶片的x方向叶尖挠度值最大,可能使叶片和塔架发生碰撞。