摩托车防抱死制动系统液压控制单元压力响应特性分析

To investigate and optimize the pressure response characteristics of the hydraulic control unit (HCU) in motorcycle anti-lock braking system (ABS) under different working conditions, the pressure response characteristics were tested, and the parameter response optimization of the control effect was studied, based on the team's self-developed control program for Bosch ABS9-HCU. Analysis results show that the pressure of the wheel cylinder decreases linearly from 35 ms to 45 ms after the start of conventional depressurization, and the iinear pressure drop of the wheel cylinder accounts for 70%-80% of the total pressure drop. The HCU performance throughout the conventional depressurization is determined by the response characteristics of the iinear pressure drop process, and the depressurization effect can be achieved within 45 ms under varying initial pressure. After the beginning of conventional pressurization, the iinear pressure rise time of the wheel cylinder is gradually shortened (51. → 21. 6 ms) with the increase of initial pressure (1. 0→ 3. 5 MPa), and the iinear pressure rise accounts for more than 90. 0% of the total pressure rise. After the iinear pressure rise ends, the conventional pressurization is basically completed. As the initial pressure increases, the number of cycles required for the completion of the step control gradually decreases. When the initial pressure is low, the pressure variation amplitude in each cycle is more uniform, and the variance of pressure variation amplitude in a single cycle is smaller. The step control process is extremely sensitive to single-cycle pressurization and depressurization time. The single-cycle pressurization time should be within 4-20 ms, and the single-cycle depressurization time should not exceed 12 ms. The changing trend of pressure can be controlled by changing the pressure holding time. The dispersion degree of the single-cycle pressure rise increases with the increase of the number of cycles, and the number of step control cycles should be controlled at three. The working time of the motor should be less than the depressurization time. After the initial pressure condition of 3. 00 MPa is optimized, a good pressure control effect is achieved. The maximum single-cycle pressure drop of the wheel cylinder is reduced by 62%, and the variance of the single-cycle pressure drop is only 0. 004 7 (MPa)². The research provides data guidance and theoretical support for the development of a motorcycle ABS control system.