中文摘要：

以某四冲程内燃机为对象，在内燃机试验台架上实际测量了多工况下主轴承的轴心轨迹，基于实测数据分析了传感器安装角和轴承半径间隙的测量偏差对主轴承轴心轨迹测量误差的影响。结果表明：传感器安装角偏差在±1°范围内时对轴承轴心轨迹的测试精度有一定影响，但影响不明显；轴承半径间隙偏差对轴承轴心轨迹测试精度有很大影响，随轴承半径间隙偏差增加，1个内燃机工作循环中轴承偏心率误差和位置角误差最大值都按比例增大。

英文摘要：

For a 4-stroke internal combustion engine, the axis orbits of the main bearing were measured under multiple conditions in the test bed. Based on the measured data, the influences of sensor mounting angle and bearing radius clearance measurement deviation on the axis orbit measurement error were analyzed. The results show that the sensor mounting angle deviation of ±1° has unobvious influence on the measuring accuracy of axis orbit, while the deviation of bearing radius clearance has great influence. The maximum errors of bearing eccentricity ratio and position angle in one cycle both increase proportionally to the increase of bearing radius clearance.