Research On A Novel Electro-Hydraulic Brake System

“Safety, Energy Conservation, Environmental Friendly” have become the main three themes of today’s world auto industry. Revolved around these themes, automotive active safety technology, intelligent technology and new energy technology have been flourished. Facing broad prospects of the future automotive industry as well as the challenges from development of a variety of new technologies, brake and its control system will undoubtedly play a core role in the implementation of active safety, brake energy recovery and driverless.Relying on the national 863 subject “Development of Vehicle Dynamic Control System for Electric Vehicle” and cooperating with enterprises, this thesis conducted the following research focus on schematic design, theoretical analysis, bench test, algorithm development, ECU development and road tests.(1) Introduced electric booster system and brake-by-wire system of next generation brake system, respectively. With a small electric vehicle as target vehicle, for example, this part completed schematic design and calculation to determine the basic parameters of the motor and transmission mechanism, then got a prototype.(2) Build a test bench and constructed control system based on d SPACE rapid control prototype, tested the motor dynamic characteristics, mainly focused on test plan design and analysis of the integrated transmission mechanism, finally we got some parameters about coulomb friction, static friction and viscous damping friction.(3) Established Lu Gre friction model to characterize the friction characteristics of the transmission mechanism and identified the model’s parameters based on genetic algorithm. Filtered sensor signals in order to obtain better control input. Identified driving behavior and pedal state based on logic threshold through lots of test analysis. Determined the “pre-basic boost + feed forward compensation” control strategy based on above analysis. In order to verify the control strategy, we took d SPACE rapid control prototype to conduct real vehicle test for the convenience of calibrating and online debugging. Designed an ECU and downloaded the code of the control algorithm generated by Embedded Coder to verify the validity of the ECU, preparing for the industrialization.(4) There are many functions of the next generation braking system that cannot be verified by real test under the present conditions, therefore, based on an integration simulation platform Pano Sim, which was developed by our group independently, this paper analysis AEB to provide a theoretical basis for in-depth follow-up research.