底盘角系统制动颤振多体动力学建模与分析

Multi-body Dynamics Modeling of Chassis Corner for Brake Creep Groan and Its Analysis

摘要:

基于多体动力学方法，考虑制动系统、悬架系统、等效传动系统的具体结构和空间位置以及制动器摩擦特性，以传动系统驱动力矩和制动压力为输入，提出了一种制动颤振瞬态动力学模型.分析了制动盘与制动块间的黏滑运动和相图特性以及制动系统和悬架系统关键部件振动特性，明确了制动颤振的主要传递路径.结果表明：制动颤振包含2种典型振动模式，一种是幅值较大、持续时间较短的冲击振动，另一种是幅值较小、持续时间较长的周期性谐波振动;制动钳和悬架关键部件均以制动盘切向振动为主，经过减振器支柱和下摆臂的传递，整车以纵向振动为主.

关键词:制动颤振; 底盘角系统; 多体动力学模型; 黏滑振动; 整车试验

Abstract:

Based on the multi-body dynamics method, a transient dynamic model of brake creep groan was proposed. In this model, the brake system, the suspension system, the structure and spatial position of equivalent transmission system and the brake friction characteristics were considered. The driving torque from transmission system and the brake pressure were regarded as inputs. The stickslip motion and phase diagram of disc against pad, the vibration of key components in brake and suspension system were obtained. In addition, the key transfer path analysis was clarified. The simulation results indicate that the brake creep groan consists of two typical vibration modes. One is the impact mode with large magnitude and short duration, and the other is the periodic mode with lower magnitude but longer duration. The tangential movement dominants the key vibration both in brake and suspension components. The vibration is transferred by the strut and control arm to the body, resulting in the longitudinal movement of the whole vehicle.

Key words:brake creep groan; chassis corner; multi-body dynamic model; stickslip motion; road test