Modal characteristics analysis of steering gear synchronous belt under pre-tension based on Abaqus

The synchronous belt is a key transmission component in automotive steering gears, and its dynamic characteristics significantly impact the NVH (Noise, Vibration, and Harshness) performance of the steering system. To investigate the vibration characteristics of the synchronous belt under pre-tension, this study takes the steering gear synchronous belt as the research object. A three-dimensional finite element model of the synchronous belt-pulley system, considering its layered structure, is established. Pre-tension is applied using the displacement loading method, and prestressed modal simulation analysis is conducted. The results show that the system’s low-order modes are primarily characterized by overall vertical bending and torsion, while medium- and high-order modes exhibit combined mode shapes and localized vibration features. When the pre-tension displacement increases from 2 mm to 4 mm, the first-order natural frequency rises from 340.69 Hz to 464.88 Hz, but the impact on the mode shape morphology of the synchronous belt is minimal. The relative error between the simulation and experimental results for the first six natural frequencies is less than 1 %, verifying the accuracy of the established model.