丘陵山地无人车振动特性试验研究

为探索丘陵山地无人车振动特性，以丘陵山地无人车为研究对象，进行了振动特性试验。在无人车车体选择11个测试点，设计6组试验方案，综合分析测点位置、发动机油门大小和路面不平度对无人车振动特性的影响。试验结果表明，测点3（车架左前部）是无人车整车最合适安装传感器位置，在无人车正常行走、油门1/2位置、挂1档工况下，加速度最大值为47.4 m/s2，加速度最小值为-50.36 m/s2，加速度平均幅值为5.092 m/s2，加速度有效值仅为6.864 m/s2，说明该测点振动表现稳定；其他合适的测点为测点4和测点9。发动机油门大小对于加速度最大值、加速度最小值、加速度平均幅值、加速度方根幅值、加速度有效值均有显著影响，同一测点下，油门1/2和油门3/4相比较初始油门，加速度平均幅值增大297.1%和322.8%。路面不平度对于无人车振动有显著影响：在水泥路面上，无人车底盘加速度值最小，而在沙壤土、黏土和干沙土三种路况下，底盘加速度值分别增加81.23%，77.91%和1.31%。同时提出降低发动机高频振动、增加阻尼、传感器工作时降低行驶速度等减振措施。

Vibration characteristics test of unmanned hilly and mountainous vehicle

The vibration characteristics of an unmanned vehicle in hilly and mountainous areas were tested. Eleven test points were selected in the body of the unmanned vehicle, and six groups of test schemes were designed to comprehensively analyze the influence of measuring point position, engine throttle, and road roughness on the vibration characteristics of the vehicle. The test results showed that among the 11 test points, test point 3 (the left front part of the frame) was the most suitable position for installing the sensor on the vehicle. When the vehicle was running, the throttle was at 1/2 position, and it was on the first gear, the maximum acceleration value of the vibration of test point 3 was 47.4 m/s2, the minimum acceleration value was -50.36 m/s2, the average acceleration amplitude value was 5.092 m/s2, and the effective acceleration value was 6.864 m/s2, which showed that the vibration performance of test point 3 was more stable. Other suitable survey points were test point 4 and test point 9. The engine throttle significantly affected the maximum acceleration value, minimum acceleration value, average acceleration amplitude value, square root acceleration amplitude value, and effective acceleration value. Under three working conditions at the same test point, the average acceleration amplitude value increased by 297.1% and 322.8% at 1/2 and 3/4 throttle compared to the initial throttle. In the simulation model, the unevenness of the road had a significant impact on the vibration of the unmanned vehicle. On cement road surface, the chassis acceleration value of the unmanned vehicle was the lowest, while on sandy loam, clay, and dry sand, the chassis acceleration value increased by 81.23%, 77.91%, and 1.31%, respectively. At the same time, the vibration reduction measures, such as reducing the high frequency vibration of the engine, increasing the damping, and reducing the driving speed when the sensor is working, are put forward.