基于微分平滑的四旋翼系绳运输系统轨迹规划

四旋翼系绳运输系统轨迹规划在航空运输领域有重要的应用。在给出轨迹规划模型的基础上,分析了系统飞行中受到的约束类型。引入微分平滑理论,利用系统的微分平滑特性将系统状态变量和控制输入的约束统一映射到平滑输出上。由于这个约束域是非线性的,基于半无限优化理论,用一个体积最大的凸多面体逼近约束域,从而将原来的非线性约束转化为凸多面体顶点的线性约束。选择多项式函数作为基函数对输出曲线进行参数化,并在时间上构建网格节点,从而将轨迹规划问题转化为有限个线性约束下确定多项式系数的最优化问题,给出了完整的轨迹规划求解步骤。仿真实验验证了所提算法的有效性。

Trajectory Planning of Quadrotor with Cable-suspended Loadbased on Differential Flatness

Trajectory planning of quadrotor with cable-suspended load has important applications in the field of air transport. The constraints in the flight are analyzed. Based on differential flatness, the constraints on state variables and control inputs are mapped into flat output. The feasible set is nonlinear. By use of the theory of semi-infinite optimization, a convex polytope with a given number of facets is used to replace the original nonlinear constraints by the convex polytopic approximation. Then the polynomial function is selected as the basis function to parameterize the output. The trajectory planning problem is transformed into an optimization problem with linear constraints. The planning algorithm is given. Simulation results demonstrate the effectiveness of the proposed algorithm.