[目的]为获取地面不平度数据用来研究耕作地面的土壤风蚀情况、含水量情况、土壤与轮胎耦合情况,设计了一种非接触式测量仪器。[方法]仪器主要由运动测试台架、数据采集、虚拟控制3部分组成。采用基于激光三角测距原理的传感器进行距离测量,利用采集设备将数据传送至上位机显示、储存和处理。基于Lab VIEW软件创建虚拟操作平台,控制带有测量设备的运动测试台完成扫描定位,测量时根据不同要求改变1~100 mm不等的采样间隔。对测试仪进行了精度检验试验。[结果]试验结果表明:地面不平度仪的测试精度在±2 mm的精度范围内,试验测量数据均方根误差为0.16 mm,地面不平度仪能够准确测量不平度数据。对于测试得到的数据进行零均值化预处理,减小了测量不利因素带来的影响。[结论]非接触式地面不平度仪能够精确测量地面不平度数据,实现自动化测量,为进一步的理论研究提供测量基础。
[ Objectives ] Surface roughness is a major contributing factor of vehicle vibration, which directly affects the reliability of powertrain and ride comfort. In addition, surface roughness values are important foundations of the research about soil wind erosion, water content, and soil-tire coupled. In order to get the surface roughness data, a special non-contact measuring instrument was designed. [ Methods ] Instruments are mainly composed of test bench, data acquisition and the virtual control panel. Based on the principle of laser triangulation sensor instrument, the instrument can achieve the function of measuring elevation by manipulating the virtual control panel on the basis of the LabVIEW software which is utilized to send commands to the MCU, control motor movement, and achieve the positioning control. The laser ranging sensors installed on the test bench measure the data that are transmitted to the PC through the data acquisition equipment, and displayed and stored by data acquisition panel. [ Results ] Through the accuracy test of the testing instrument,it verifies the reliability of instrument testing precision. The test results show the test precision of ±2 mm, and the experimental data of RMS error of 0.16 mm. According to test results ,this paper applies the zero mean on test data prepro- cessing. It can improve the accuracy of the measurement data which is fundamental to subsequent researches on soil-tire coupled process. [ Conclusions] Non-contact surface roughness instrument capable of accurately measuring roughness of ground data, and hence the realization of automatic measurement, provide a foundation of measuring for further theoretical research.