移动机器人的最优轨迹跟踪控制研究

Research for Optimal Trajectory Tracking of a Mobile Robot

针对移动机器人在复杂环境下的路径规划与轨迹跟踪控制,提出了一种最优轨迹跟踪控制方法。首先,通过理论分析给出了移动机器人的运动学模型和对避障问题的描述,推导出了位置与姿态方程以及目标函数表达式;其次,介绍了萤火虫算法的寻优机制,并采用广义方向学习策略来改进原算法的性能;同时,引入NUBRS曲线来光滑处理局部路径,缩短总路径长度;进而,将移动机器人系统分成位置与姿态两个控制环,分别设计PD控制律来实现其稳定的轨迹跟踪控制;最后,通过仿真与实验验证了所提方法的有效性,结果表明:(1)改进后的萤火虫算法能够为移动机器人规划出一条避障且可行走的轨迹;(2)基于PD控制策略,移动机器人能够有效地实现轨迹跟踪。

Aiming at the path planning and trajectory tracking control for a mobile robot,a novel optimal trajectory tracking control method has been proposed in this paper.Firstly,we have analyzed the kinematical model and obstacle avoidance in theory.The equations of attitude and position and the objective function have been obtained.Secondly,the search mechanism of glowworm swarm algorithm has been introduced and a generalized orientation learning strategies has been employed to improve the performance.Meanwhile,the NUBRS curve has been used to smooth the trajectory which can reduce the length of the path.Then,the structure of the mobile robot has been divided into two control loops,i.e.,attitude loop and position loop.And a PD control strategy has been designed for the trajectory tracking.Lastly,the effectiveness of our proposed method has been tested through simulation and experiment.The results show that the mobile robot can obtain a feasible path through the glowworm swarm algorithm and can realize the trajectory tracking control through the PD controller.