Authors

Abstract

Measuring and analysing the roughness of agricultural field and road have great significance for studying the characteristics of tractor dynamic response. This study was designed to analyse and compare the roughness characteristics of agricultural field and asphalt road profiles. A profiling apparatus was developed to measure field and road surface profiles of parallel tracks. The profile measurements were conducted in a grass field, a corn stubble field, a harvested potato field and on an asphalt road. The root mean square value and two spectrum parameters of surface profiles were calculated and analysed to investigate the roughness characteristics of fields and asphalt road. The results of the study indicate that for the values of the agricultural field and asphalt road surface roughness, waviness and roughness index are both positive associated with the root mean square value. Most of the waviness values of all measured field profiles were less than 2 with the average of 1.8, while the waviness values of all measured asphalt road profiles were greater than 2 with the average of 2.08. The roughness of both field and asphalt road profiles can be distinguished by the power spectral density fitting method. However, it has better performance in characterizing asphalt road profiles than characterizing field profiles with the power spectral density fitting method.

Abstract in Chinese

测量和分析农田和路面的不平度对研究拖拉机动态响应特性具有重要意义。本文为分析和比较农田地面与沥青路面的不平度特征，研制了一种地面不平度测量装置，分别在田间草地、玉米茬地、马铃薯收获地和沥青路面上开展了不平度测试试验。通过分析测试地面不平度的均方根（RMS）值及两个频谱特征参数，研究了农田地面和沥青路面的不平度特性。结果表明，农田地面和沥青路面不平度频率指数W和不平度系数C均与不平度均方根RMS呈正相关；测试的三种农田地面不平度频率指数W值多数都小于2，其平均值为1.8，而沥青路面不平度频率指数W值都大于2，其平均值为2.08；利用PSD拟合方法可以有效识别农田地面与沥青路面的不平度特征，但用于沥青路面的不平度特征识别具有更好的效果。