摘要
针对温室喷药移动机器人,为解决作物种植密集,地面障碍与空间障碍并存等非结构化环境因素对其路径跟踪运动控制精度的影响,根据移动机器人运动学特性并充分考虑温室环境因素,提出一种滑模控制方法保证系统对外部干扰具有较强的鲁棒性。与此同时引入新型加权增益趋近律解决滑模控制固有的抖振问题,在积分项中引入负的加权值,可有效避免当系统状态不在滑模面时的切换增益的增大,使得控制器输出量平滑,进而使得温室环境中喷药移动机器人的实际运动轨迹跟随理想作业路线的过程中不会产生较大的波动,因此可以避免在作业区域产生较严重的重喷和漏喷现象。实验结果表明了所设计积分加权增益趋近律滑模控制方法的有效性和可行性,其研究成果为温室作物实施精准喷药,提高我国农业自动化水平奠定理论基础。
For the spraying mobile robot working in greenhouse environment, in order to solve the bad effect of the complex unstruc tured environment of intensive planting, ground obstacles and spatial disorders coexisting on the path tracking control precision, Accord ing to the kinematics of the mobile robot and considering fully the impact of environmental factors, a sliding mode control scheme is pro posed to assure the robustness to the system uncertainty including parameters＇variation, external disturbances and nn modeled part, so as to enhance the tracking performance of the mobile robot. Meanwhile, a novel weighed integral gain reaching law is introduced to a void significantly increasing of the switch gain when the system states are not in the sliding mode phase and can solve the chattering problem of sliding mode control. Moreover, the asymptotical stability of the closed loop system is proved using Lyapunov function. The simulation and experimental results show that the proposed control method provides a superior tracking performance in the presence of the parameter uncertainties. The research results have established the theoretical foundation for precision spraying the greenhouse crops and improving the agricultural automation level.
出处
《控制工程》
CSCD
北大核心
2013年第6期1203-1207,共5页
Control Engineering of China
基金
江苏省高校优势学科建设工程资助项目(苏政办发〔2011〕6号)
镇江市农业科技支撑计划(NY2011013)
江苏省高校研究生科研创新计划项目(1221140046)
关键词
移动喷药机器人
轨迹跟踪
滑模控制
加权增益趋近律
spraying mobile robot
trajectory tracking
sliding mode control
weighed integral gain reaching law
