摘要
针对高秆作物生长中后期无人化田间机械作业需求,在遥控式小型全液压驱动高地隙履带车的基础上,设计了履带车自动行走控制系统。该系统以STM32控制器为控制核心,通过搭载测距、触杆、角速度等传感器得到有效信号,精确控制液压电磁阀开闭时间,使履带车旋转对应的角度,进而使履带车在田间可根据作物生长情况对行行走。为得到履带车在不同偏移状态下的转角,建立了该履带车转向运动模型以及标准田间偏移模型,推导出了履带车在不同对应状态下理论转角的表达式。考虑到履带车转向时存在滑移、滑转的现象,对履带车在不同行驶速度下的转向角速度进行了标定,试验得出实际转向角速度在理论转向角速度的63%~67%之间。为验证液压车自动行走系统的行走效果,在硬质水泥路面进行了两种作业模式的履带车通过性试验,使用集思宝G970高精度GNSS设备精确测定了履带车转向轨迹,数据结果显示,两种行走模式下逆时针行走时,接收机相位中心转向轨迹半径分别为5. 573、5. 572 m,顺时针分别为4. 704、4. 645 m,两种模式下接收机相位中心偏移量在0. 163~0. 285 m之间,车架几何中心转向轨迹半径与实际半径相对误差在0. 92%~2. 14%之间,履带车对行行走通过效果良好,可为田间自走式履带车辆自动行走控制系统的设计研究提供参考。
In response to the demand of unmanned field machinery in the middle and late stages of highstalk crop growth,the automatic walking control system was designed based on a remote control type of small high clearance hydraulic tracked vehicle. The STM32 controller was taken as control core,and the effective signal was obtained by using sensors such as ranging,contact rod,angular velocity and so on,the system can precisely control the opening and closing time of the hydraulic solenoid valve,so that the crawler vehicle can rotate the corresponding angle,and it can walk in the field according to the growth of crop. In order to obtain the angle of rotation of the tracked vehicle under different offset transitions,the steering model of the tracked vehicle and the standard field offset model were established,and the expression of theoretical angle of tracked vehicle in different corresponding states was deduced.Considering the phenomenon of slippage and slippage when the tracked vehicle was turning,the steering angular speed of the tracked vehicle at different driving speeds was calibrated. The test results showed that the actual steering angular velocity was between 63% ~ 67% of the theoretical steering angular velocity. In order to verify the walking effect of the hydraulic vehicle automatic walking system,the track vehicle passing test of two working modes was carried out on the hard cement road surface,and the track trajectory of the tracked vehicle was accurately measured by using Unistrong G970 multi-frequency GNSSsystem. The results showed that the two-way mode of the receiver’s phase center turning trajectory was5. 573 m and 5. 572 m in counterclockwise travel and 4. 704 m and 4. 645 m in clockwise walking,respectively,receiver phase center offset was between 0. 163 m and 0. 285 m. The relative error of turning track radius and actual radius of frame geometric center was between 0. 92% and 2. 14%. The tracked vehicle had good effect on automatic walking,which provided a reference for the design of automatic walk
出处
《农业机械学报》
EI
CAS
CSCD
北大核心
2018年第S1期456-462,469,共8页
Transactions of the Chinese Society for Agricultural Machinery
基金
现代农业产业技术体系建设专项(CARS-03)
河南省现代农业产业技术体系岗位专项(S2018-02-G07)
河南省烟草公司科技专项(HYKJ1206/2016)
关键词
高地隙
履带车
液压
自动行走
控制
差分定位
high clearance
caterpillar vehicle
hydraulic pressure
automatic walking
control
differential positioning
