摘要
为了提高作业装备在果园与树林行间的自主导航性能,该研究提出一种基于最小二乘法与支持向量机(Support Vector Machine,SVM)融合的树行识别与导航方法。研究采用履带式小型喷雾机为作业平台,通过低成本的单线激光雷达获取果园或树林环境点云数据,融合姿态传感器进行数据校正,利用最小二乘法拟合识别树行,结合SVM算法,预测果园行间中心线,作为作业平台的参考导航线。在桃园、柑橘园、松树林3种不同的行间环境对导航算法进行了测试验证,并以松树林导航为例进行分析。试验结果表明:该导航算法最大横向偏差为107.7 mm,横向偏差绝对平均值不超过17.8 mm,结合作业平台的行驶轨迹,说明该导航算法能够保证作业平台沿树行行间中心线自主导航行驶,能够满足作业装备在果园与树林行间自主导航作业的需求。
Autonomous navigation has widely been served as agricultural working platforms in smart farming.A few kinds of sensors,such as GPS and camera,are commonly used as conventional.However,the automatic navigation cannot be extended suitable for orchard environment,due mainly to canopy closing and the variation of light intensity.In this study,an inter-row automatic navigation was developed for a track chassis using an Inertial Measurement Unit(IMU)and Light Detection And Ranging(LIDAR),thereby improving the capability of in-orchard navigation under agricultural working platforms.The track chassis was specifically developed for orchard conditions,including a chassis,a driving implement,a power implement,and a range extender,where the specific size was 1575 mm×1190 mm×1355 mm.The detection and control systems were performed on a host and a slave computer.The host computer was in charge of data processing to obtain navigation paths and orders,while the slave one was to control motors using Pulse-Width Modulation(PWM).An SC-AHRS-100D2 was selected as the IMU in sensors and units,while RPLIDAR S1 was utilized as the LIDAR scanner.The orientation and pose of the platform were acquired under the IMU.Meanwhile,the orchard condition was also scanned by the LIDAR.First,the orientation and pose from the IMU were exploited to modify the data from the LIDAR,so that the platform remained in correct moving directions.Quaternions were transformed into Euler angles during the data processing.The tree lines on both sides were then extracted using least square,where an average line between two lines was calculated.Next,mathematical models were established to combine with the Support Vector Machine(SVM).An optimized classification line of environment between tree lines was computed as the navigation path of the track chassis platform,in order to ensure a maximum interval between the tree lines on both sides.Moreover,a Proportional-Incremental-Differential(PID)controller was employed to control the platform motion using the path inform
作者
刘星星
张超
张浩
杨圣慧
江世界
郑永军
苏道毕力格
万畅
Liu Xingxing;Zhang Chao;Zhang Hao;Yang Shenghui;Jiang Shijie;Zheng Yongjun;Su Daobilige;Wan Chang(College of Engineering,China Agricultural University,Beijing 100083,China;Engineering Research Center of Agricultural Equipment and Facilities,Ministry of Education,Beijing 100083,China;College of Mechanical and Electrical Engineering,Tarim University,Alar 843300,China)
出处
《农业工程学报》
EI
CAS
CSCD
北大核心
2021年第9期157-164,共8页
Transactions of the Chinese Society of Agricultural Engineering
基金
国家重点研发计划项目(2018YFD0700603)
南疆重点产业创新发展支撑计划项目(2020DB003)。
