机场行李牵引车振动问题诊断与优化研究

Diagnosis and Optimization of Vibration Issues in Airport Baggage Tractors

摘要: 针对某机场行李牵引车在常规作业工况下出现的剧烈低频振动问题，本文开展了系统的故障诊断与优化研究。采用连续多点位加速度采集与频谱分析方法，发现驾驶室振动主频(2~4 Hz)与车轮旋转频率严格一致，初步判定振动激励源位于车轮旋转机构。通过轮毂单体跳动测试，测得径向跳动量高达3.8 mm。通过刚柔耦合环模型，建立了轮毂径向跳动–径向力波动–整车垂向响应的传递关系，揭示出车轮旋转频率与车辆质量刚体模态频率重合导致的共振放大机制。以锻造轮毂替换及跳动公差严控为核心实施整改，整改结果显示：轮毂径向跳动降至0.4 mm，驾驶室地板加权加速度均方根值由0.65 m/s²降至0.29 m/s² (降幅55.4%)，低频共振峰完全消除。基于量纲分析提出了无量纲跳动参数λ，并初步建议机场行李牵引车轮毂径向跳动在用车限值为2.0 mm、新装轮毂为1.0 mm。本文为机场特种车辆振动故障诊断与行驶平顺性提升提供了可量化的技术路径。

Abstract: To address the severe low-frequency vibration problem of an airport baggage tractor under normal operating conditions, this paper presents a systematic fault diagnosis and optimization study. By employing continuous multi-point acceleration acquisition and spectrum analysis, it was found that the dominant vibration frequency of the cab (2~4 Hz) strictly coincides with the wheel rotation frequency, leading to the preliminary conclusion that the vibration excitation source lies in the wheel rotating mechanism. Hub runout tests revealed a radial runout as high as 3.8 mm. Using a rigid-flexible coupling ring model, the transmission relationship from hub radial runout to radial force fluctuation and then to vehicle vertical response was established, uncovering a resonance amplification mechanism caused by the coincidence between the wheel rotation frequency and the vehicle’s rigid-body modal frequency. Corrective measures were implemented focusing on replacing the hub with a forged one and strictly controlling runout tolerances. Results show that the hub radial runout was reduced to 0.4 mm, and the weighted root-mean-square acceleration of the cab floor dropped from 0.65 m/s² to 0.29 m/s² (a reduction of 55.4%), with the low-frequency resonance peak completely eliminated. A dimensionless runout parameter λ is proposed based on dimensional analysis, along with preliminary recommendations for hub radial runout limits: 2.0 mm for in-service airport baggage tractors and 1.0 mm for newly installed hubs. This study provides a quantifiable technical pathway for vibration fault diagnosis and ride comfort improvement of airport special vehicles.