拖拉机最小转向圆半径静态测试系统设计与试验  

Design and experiment of tractor minimum turning radius static test system

作　　者：张浩男 张友坤[1] 卢延辉[1] ZHANG Haonan;ZHANG Youkun;LU Yanhui(College of Automotive Engineering,Jilin University,Changchun 130025,China)

机构地区：[1]吉林大学汽车工程学院,吉林长春130025

出　　处：《中国测试》2022年第7期128-133,共6页China Measurement & Test

基　　金：国家十三五重点研发计划(2017YFD0700202)。

摘　　要：拖拉机最小转向圆半径是拖拉机转向性能和通过性能的重要参数,属于拖拉机整机装配后的下线检测项目之一。该文开发一种拖拉机最小转向圆半径静态测试系统,用室内试验替代现有的场地试验,测试系统主要包括工控机、步进电机控制滑台和激光位移传感器,采用CANopen协议作为现场通信总线协议。该系统通过激光位移传感器扫描记录拖拉机转向轮极限转角下的断面轮廓,利用最小方差估计算法识别出轮胎胎冠上的对称区域,然后通过轮胎断面轮廓确定轮胎转角,带入拖拉机结构参数,进而计算得到拖拉机最小转向圆半径;采用最优化信号处理算法,实时计算采样信号的均值和方差直到获得最优值,以提高系统的测试精度。测试试验结果表明:该测试系统的角度测试误差在±0.5°以内,并且测试时间小于2 min,测试系统的可靠性和实用性得到验证。The minimum turning circle radius of tractor is an important parameter of tractor steering performance and trafficability,which is one of the offline testing items after the tractor is assembled.In this paper,a minimum turning radius static test system is developed,which replaces the current field test with inroom test.The test system is mainly composed of a computer,stepper motors and laser displacement sensors,and the CANopen protocol is adopted as the field bus.After scanning and recording the cross-section profile of tractor steering wheel under the limit angle by laser displacement sensors,the system uses the minimum variance estimation algorithm to identify the symmetrical area on the tire crown,then determines the tire angle through the tire cross-section profile,brings in the tractor structural parameters,and then calculates the minimum turning circle radius of tractor;in order to improve the test accuracy of the system,the optimal signal processing algorithm is used to calculate the mean and variance of the sampled signal in real time until the optimal value is obtained.The test results show that the test angle error of the developed test system is±0.5°,and the whole test time is within 2 minutes.The reliability and practicability of the test system have been verified.

关 键 词：最小转向圆半径 激光位移传感器 拖拉机 最小方差估计 

分 类 号：S219.1[农业科学—农业机械化工程] TB9[农业科学—农业工程]