Development Of Automobile Sensotronic Brake Control System

Sensotronic brake control system (SBC) is the development trend of automobile braking system. SBC cancels some machine equipments such as vacuum booster and vacuum pump. Sensors sense the driver's braking intention, and send the signal to SBC ECU. The braking fluid is supplied by electric motor, which is controlled by electron and can supply continuum and steady high pressure oil. So SBC can response braking fast and precisely.This paper use Matlab/Simulink simulation tool box to simulate SBC with threshold control logic and PID associated with threshold control logic, and get preferable simulation result. The control object is the wheel's slip ratio. The basic idea of threshold control method is that slip ratio is main threshold and braking decrease speed and vehicle speed is assist threshold. The method of PID associated with threshold uses the advantages of both PID and threshold to improve the braking system effectThe programs of two control methods are programmed with assemble language. The programs main include collecting digital signals, calculating slip ratio and controlling output. Digital signals collection used HIS maintenance register loading interrupt method. Slip ratio calculate and control output part used HSO software timer 0 interrupt method. Through debugging in WAVE emluator, the effect indicates that the programs meet desire of design.The core ship of SBC electronic controller used Inte180C 196KB. The periphery dispose circuits include single chip +5V power supply circuit, analog signal collection circuit, digital signal collection circuit, control output circuit and cluster gob message circuit with computer. Each circuit can achieve corresponding function though serious designing and debugging. In the paper circuit diagram and PCB diagram are designed, and maded corresponding circuitboard.In the paper hydraulic system of SBC test bed is designed and debugged. Its principle is that SBC controller controls solid relays to open or close electromagnetism valve. This can realize auto control of system pressure.At last SBC character test system is build up. It is made up of single wheel braking test bed, SBC controller, software of system and hydraulic control system. On the test system a lot of test is done. The test phenomenon and result indicate that the slip ratio is mainly in optimal area during braking process, there is not lock phenomenon, and the wheel is steadily braked in short time. All of these explain the system has well brake stability and controllable. So the designing SBC system can efficiently improve automobile run safety. By the compare of many results of test, in the SBC test system the control effect of with threshold control combine with PID method is better than effect of threshold control method.Sensotronic brake control system (SBC) is the development trend of automobile braking system. SBC cancels some machine equipments such as vacuum booster and vacuum pump. Sensors sense the driver's braking intention, and send the signal to SBC ECU. The braking fluid is supplied by electric motor, which is controlled by electron and can supply continuum and steady high pressure oil. So SBC can response braking last and precisely.This paper use Matlab/Simulink simulation tool box to simulate SBC with threshold control logic and PID associated with threshold control logic, and get preferable simulation result. The control object is the wheel's slip ratio. The basic idea of threshold control method is that slip ratio is main threshold and braking decrease speed and vehicle speed is assist threshold. The method of PID associated with threshold uses the advantages of both PID and threshold to improve the braking system effectThe programs of two control methods are programmed with assemble language. The programs main include collecting digital signals, calculating slip ratio and controlling output. Digital signals collection used HIS maintenance register loading interrupt method. Slip ratio calculate and control output part used HSO software timer 0 interrupt method. Through debugging in WAVE emluator, the effect indicates that the programs meet desire of design.The core ship of SBC electronic controller used Intel80C 196KB. The periphery dispose circuits include single chip +5V power supply circuit, analog signal collection circuit, digitalsignal collection circuit, control output circuit and cluster gob message circuit with computer. Each circuit can achieve corresponding function though serious designing and debugging. In the paper circuit diagram and PCB diagram are design, and corresponding circuit board is made.In the paper hydraulic system of SBC test bed is designed and debugged. Its principle is that SBC controller controls solid relays to open or close electromagnetism valve. This can realize auto control of system pressure.At last SBC character test system is build up. It is made up of single wheel braking test bed, SBC controller, software of system and hydraulic control system. On the test system a lot of test is done. The test phenomenon and result indicate that the slip ratio is mainly in optimal area during braking process, there is not lock phenomenon, and the wheel is steadily braked in short time. All of these explain the system has well brake stability and controllable. So the designing SBC system can efficiently improve automobile run safety. By the compare of many results of test, in the SBC test system the control effect of with threshold control combine with PDD method is better than effect of threshold control method.