基于高斯伪谱法的翼伞系统复杂多约束轨迹规划

翼伞系统在实际环境中飞行时易受到风场以及地形环境等复杂干扰的影响,无法精确归航,控制难度较大。针对该问题,提出了一种针对复杂多约束条件的翼伞系统的最优控制轨迹规划方法,可同时实现翼伞系统在复杂环境下逆风对准、精确着陆以及控制量全局最优的控制目标。首先,建立了风场干扰下的翼伞系统模型;然后,通过引入地形环境曲面,将复杂环境转化为实时路径约束,将轨迹着陆偏差以及逆风雀降转化为终端约束,并考虑控制量消耗最小为目标函数,以此将复杂环境下的翼伞系统的轨迹优化转化为一系列非线性的带有复杂约束的最优控制问题;最后,采用高斯伪谱法将多约束最优控制问题转化为易于求解的非线性规划问题。通过设立3组复杂环境仿真实例和实验验证,表明本文方法使翼伞系统在多种较恶劣的复杂环境中有效应对多类约束条件,规划出控制量全局最优的可行轨迹。与已有的混沌粒子群优化算法相比,本文方法具有较好的最优性和较高的精度。

Trajectory planning of parafoil system with intricate constraints based on Gauss pseudo-spectral method

The parafoil system is commonly affected by complex interferences,such as wind field and terrain environment,leading to imprecise homing and increasing control difficulty.A trajectory optimization of the parafoil system subjected to intricate constraints is proposed to realize accurate landing,flare landing against the wind,and global optimal control.A model for the parafoil system in the wind field is built.To transform the problem of trajectory optimization of the parafoil system in complex environment to the problem of optimal control with a set of nonlinear and intricate constraints,the complex terrain environment is converted into real-time path constraint by introducing into terminal constraints the terrain environment surface,the landing deviation and flare landing,and the objective function with minimum control consumption is defined.Gauss pseudo-spectral method is applied to transform the problem of optimal control with intricate constraints to the problem of easily solvable non-linear programming.Numerical simulation and experimental results show that the proposed method can efficiently plan out an optimal trajectory with high precision to meet the constraints in a variety of complex environments.A comparison with the existing method of chaotic particle swarm optimization demonstrates the outstanding performance of the proposed method.