农用轮式铰接车辆滑模轨迹跟踪控制算法
针对农用轮式铰接车辆驾驶员工作条件恶劣的问题,该文提出了一种应用于无人驾驶系统的滑模变结构控制铰接车精确轨迹跟踪的方法。首先推导出了铰接车的运动学模型,根据该模型建立实际行驶轨迹与参考轨迹偏差的模型,之后针对偏差模型设计滑模变结构路径跟踪控制器,该控制器使用Ackermann公式设计,控制律采用指数趋近律使系统有较快的响应和较小的抖振,同时,为了进一步抑制滑模控制器固有的抖振问题,将趋近律中的符号函数替换为连续函数,以避免趋近律数值产生阶跃变化,并用Lyapunov函数证明了其稳定性,最后在硬件在环仿真中验证了控制器的实时性和路径跟踪质量。结果表明,该控制器在硬件在环仿真环境下可将横向位置偏差...
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Published in | 农业工程学报 Vol. 31; no. 10; pp. 198 - 203 |
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Main Author | |
Format | Journal Article |
Language | Chinese |
Published |
北京科技大学机械工程学院,北京,100083%北京科技大学计算机与通信工程学院,北京,100083
2015
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Subjects | |
Online Access | Get full text |
ISSN | 1002-6819 |
DOI | 10.11975/j.issn.1002-6819.2015.10.026 |
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Summary: | 针对农用轮式铰接车辆驾驶员工作条件恶劣的问题,该文提出了一种应用于无人驾驶系统的滑模变结构控制铰接车精确轨迹跟踪的方法。首先推导出了铰接车的运动学模型,根据该模型建立实际行驶轨迹与参考轨迹偏差的模型,之后针对偏差模型设计滑模变结构路径跟踪控制器,该控制器使用Ackermann公式设计,控制律采用指数趋近律使系统有较快的响应和较小的抖振,同时,为了进一步抑制滑模控制器固有的抖振问题,将趋近律中的符号函数替换为连续函数,以避免趋近律数值产生阶跃变化,并用Lyapunov函数证明了其稳定性,最后在硬件在环仿真中验证了控制器的实时性和路径跟踪质量。结果表明,该控制器在硬件在环仿真环境下可将横向位置偏差、航向角偏差、曲率偏差分别控制在0.21 rad(12°)、100 mm、0.17rad(1°)、0.005 m-1附近,各向偏差均在10 s内达到平衡,且误差控制在5%以内,铰接车能有效跟踪参考路径。该研究为农用轮式铰接车辆实现无人驾驶提供参考。 |
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Bibliography: | 11-2047/S vehicles;control;models;articulated vehicle;path tracking;Hardware-In-the-Loop The articulated frame steering vehicles (ASV) are widely implemented in agriculture, mining, construction and forestry sectors due to their high maneuverability. The ASVs, however, are known to possess lower dynamic stability and yield high magnitude of whole-body vibration, which are reported to be harmful to the operators. Automatic driving system is thus necessary for the ASVs to exclude the human driver from detrimental operations, especially for the agricultural ASV. In order to enable the automation of ASV, path tracking strategies are essential to maintain the normal work of the vehicles. As the ASV dynamics significantly are different from the conventional vehicles with front wheel steering, the path tracking controller derived for conventional vehicles is considered not to be applicable for the ASVs. Moreover, large variations of the vehicle load and the off-road excisions challenge the robustness of path tracking |
ISSN: | 1002-6819 |
DOI: | 10.11975/j.issn.1002-6819.2015.10.026 |