轮胎胎压和车速对无悬架拖拉机横向乘坐振动特性的影响  

Influence of tire pressure and forward speed on lateral ride vibration characteristics for unsuspended tractor

作　　者：薛金林[1] 汪珍珍[1,2] 李毅念 丁启朔[1,2] 林相泽 

机构地区：[1]南京农业大学工学院,南京210031 [2]江苏省智能化农业装备重点实验室,南京210031

出　　处：《农业工程学报》2017年第19期94-101,共8页Transactions of the Chinese Society of Agricultural Engineering

基　　金：国家自然科学基金资助项目(51275249);江苏省自然科学基金(BK20151436)

摘　　要：为研究轮胎胎压和行驶速度对驾驶员横向乘坐振动特性的影响,该文以两轮驱动式无悬架国产拖拉机为研究对象,建立无悬架拖拉机横向-垂向平面三自由度模型,通过仿真和试验相结合,分别获取不同轮胎胎压和行驶速度下拖拉机座椅处横向加速度功率谱密度、横向加速度均方值以及总加权加速度均方根值,并分析各自的影响规律。结果表明:拖拉机座椅处横向固有频率试验值与理论计算值的最大相对误差为4.67%,座椅处横向加速度均方根试验值随后轮胎胎压和速度的变化规律与仿真是一致的,且试验值比仿真值要小,其相对误差最大值为5.26%,误差均在可接受范围内,表明建立的理论和仿真模型是可行的;前轮胎压的变化对两轮驱动式拖拉机乘坐横向振动特性的影响不大;当轮胎胎压不变时,试验获取的拖拉机座椅处总加权加速度均方根值随行驶速度的增大而增大;当行驶速度不变时,总加权加速度均方根值随后轮胎压的增大而波浪式增大。该研究为拖拉机多维减振悬架系统的设计提供参考。The operators of agricultural tractors experience whole-body vibration when they drive tractors, and the main influence factors to ride vibrations of the operators are terrain roughness, tractor speed, tire type, pressure, and so on. In this paper, the effects of tire pressure and forward speed on lateral ride vibration characteristics of a two-wheel drive unsuspended tractor was studied by means of a theoretical simulation and experimental analysis. A CF700 tractor without suspensions from Changfa Group was chosen as the research object, and a new theoretical vibration model was constructed for the two-wheel drive unsuspended tractor with 3 degrees of freedom including the lateral and roll and vertical directions of ride vibration in Y-Z plane. Simulation and real tractor experiments were conducted respectively to obtain the natural frequencies of lateral vibration, root mean square （RMS） of lateral acceleration and RMS of total weighted acceleration on the tractor seat under different tire pressures and forward speeds of the tractor, and thus to analyze their respective influence laws. Simulation model was built up on the basis of the constructed state space equation of tractor seat vibration system by using MATLAB/Simulink software, and then simulation was performed when rear tire pressures varied from 60 to 180 kPa with the increment of 30 kPa and 4 forward speeds of 3.5, 6, 9 and 12 km/h were chosen. Meanwhile, driving experiments of the CF700 tractor were carried out on an ISO-5008 standard trial track with 100 m length under the same conditions of rear tire pressures and forward speeds, while front tire pressures were considered from 120 to 240 kPa with the increment of 30 kPa. Firstly, the tests were repeated 3 times at the different forward speeds, when the front tire pressure was fixed to 210 kPa, while the rear tire pressure was changed from 60 to 180 kPa with the increment of 30 kPa. Then, the tests were repeated 3 times at the different forward speeds, when the rear tire pressure was fixed to 120

关 键 词：拖拉机 轮胎 胎压 行驶速度 振动特性 

分 类 号：S219.1[农业科学—农业机械化工程]