基于触感引导的小型水田行进底盘自动对行方法  

Design and experiment of the tactile guidance system for the automatic alignment of small paddy moving chassis

作　　者：陈学深[1] 熊悦淞 齐龙[1] 王宣霖 程楠 梁俊 刘善健 Chen Xueshen;Xiong Yuesong;Qi Long;Wang Xuanlin;Cheng Nan;Liang Jun;Liu Shanjian(College of Engineering,South China Agricultural University,Guangzhou 510642,China)

机构地区：[1]华南农业大学工程学院,广州510642

出　　处：《农业工程学报》2022年第21期8-15,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金(51575195);广东省基础与应用基础研究基金项目(2021A1515010831);广州市科技计划项目(202206010125)。

摘　　要：为了解决小型水田底盘因路径偏差导致的稻苗碾压损伤问题,该研究提出一种基于触感引导的自动对行方法。采用自制的感测器获取稻株定位历程触感数据,通过数据的分割阈值设定、区域谷值提取、横向距离标定获得感测器与稻株的横向距离。根据水稻机械化移栽行距规整性,利用行距与定位数据几何关系校验稻株定位数据,解算获得稻列方向相邻稻株中点位置,实现对行目标点坐标提取。基于时变坐标系跟踪方法,控制转向电机实时校正路径偏差,实现小型水田底盘自动对行。田间性能试验表明:当行进速度为0.5m/s时,自动对行绝对误差平均值为3.11cm、绝对误差标准差为1.10 cm、绝对误差最大值为4.75 cm,研究成果为水田环境作业底盘自动导航提供了新思路和借鉴。Chassis alignment can mainly include the satellite navigation,visual guidance,and manual remote control in the small paddy.However,some problems have led to the damage to rice seedlings in the alignment process,such as the low navigation accuracy,large background interference,and multiple line of sight obstacles.In this study,a tactile-guided system was proposed for the automatic alignment of small paddy chassis.Firstly,a self-developed tactile sensor was used to acquire the tactile data,in which a flexible bending sensor was used as the core element for the tactile data acquisition.The bending sensor was placed between several carbon fiber sheets,in order to improve the own bending stiffness and also to suppress the own oscillation.Secondly,the data was processed to obtain the localization coordinates of the rice plant.The positive relationship between the degree of bending of the sensor and the output voltage was utilized to obtain the information on the position of the rice plant.Three steps were included the data segmentation threshold setting,region valley extraction,and lateral distance calibration.The valid unit of tactile sensing was extracted to set a segmentation threshold.The useless data was filtered out in the non-contact area,and the interference data from the own slight vibration.The data in the sensing unit was further processed to extract the voltage valley value in the sensing area,in order to achieve the initial extraction of the location point of the rice plant.The localization point data was converted into the lateral distance between the rice plant and the sensor by the sensor mapping.Thirdly,the positioning points of rice plants were calibrated,according to the regularity that the sum of the lateral distance measured by the left sensor and the lateral distance measured by the right sensor was equal to the rice row distance.As such,the pseudo-localization points of rice plants were eliminated to improve the reliability of rice plant positioning.Finally,a tracking mode with time-varying coord

关 键 词：水稻 感测器 自动化 触觉 定位 对行 

分 类 号：S147.2[农业科学—肥料学]