基于贝塞尔曲线的机器人非时间轨迹跟踪方法  

Non-time trajectory tracking method based on Bezier curve for robot

作　　者：余伶俐[1] 龙子威 周开军[2] 

机构地区：[1]中南大学信息科学与工程学院,长沙410083 [2]湖南商学院计算机与信息工程学院,长沙410205

出　　处：《仪器仪表学报》2016年第7期1564-1572,共9页Chinese Journal of Scientific Instrument

基　　金：国家自然科学基金(61403426;61304253)项目资助

摘　　要：在复杂环境的轨迹跟踪过程中,针对移动机器人不确定时延导致控制品质下降问题,提出基于五次贝塞尔(Quintic Bezier)曲线的移动机器人非时间参考轨迹跟踪控制方法。首先,利用Quintic Bezier曲线对规划路径点进行平滑,并根据连续约束进行优化,完成多段Quintic Bezier曲线的光顺拼接,获得平滑且连续的轨迹;而后以Quintic Bezier曲线参数u作为中间映射量,构建路径长度与轨迹坐标间的状态映射模型,设计移动机器人非时间运动参考量;在此基础上,根据移动机器人运动学模型,提出一种奇异点旋转映射技术,消除奇异点对轨迹跟踪控制品质的影响。实验结果说明,所用方法能提高规划路径的平滑性与连续性,增强移动机器人不确定时延跟踪控制的鲁棒性,避免了奇异点的影响。In the trajectory tracking process in complex environment,aiming at the problem of control quality degradation caused by the uncertain time delay of mobile robot,a mobile robot non-time based trajectory tracking control method based on quintic Bezier curve is proposed. Firstly,quintic Bezier curve is utilized to smooth the planned path points; optimization is conducted according to continuity constraints,and multiple segment quintic Bezier curves are joined together smoothly to obtain a smooth and continuous trajectory.Secondly,the parameter u of the quintic Bezier curve is taken as an intermediate mapping bridge,the state mapping model between path length and trajectory coordinates is built,so that mobile robot non-time motion reference parameters are designed. On this basis,according to mobile robot kinematics model,a singular point rotation mapping technique is proposed,which can eliminate the negative influence of singular point on the control quality of trajectory tracking. Experiments results prove that the proposed method can improve the smoothness and continuity of the planned path,enhance the robustness of uncertain time delay control of mobile robot,and get rid of the influence of singular points.

关 键 词：移动机器人 非时间参考跟踪 路径平滑 五次Bezier曲线 

分 类 号：TH868[机械工程—仪器科学与技术]