| It is a tendency for electric vehicle to drive its subsystems by electricity, and the x-by-wire technology develops quickly. As the branch of the x-by-wire technology, not only dose the brake-by-wire technology improve brake performance of vehicle but also it has the advantages of environmental protection and energy conservation. In the paper, a new kind of power-driven brake apparatus was designed and developed, and the research on its structure, performance and control method is conducted systematically. Saddle piece test indicated that the power-driven brake apparatus have the characteristics of simple structure, reliable operation, stable performance and accurate control.First of all, base on principle and demand of the BBW brake, two structural design proposals and computing methods were proposed; the actuator rig of BBW was developed. In order to confirm the rationality of linear actuator selected and testified whether linear actuator can meet the performance demand of brake system, braking process of electrical controlled brake system was set up by the tool of Matlab/Simulink.Secondly, the hardware and software of electrical controlled brake system were developed. chose electrical controlled brake system CPU; Minimum system circuit including power circuit, interface circuit, reset circuit and clock circuit were designed. The circuit of regulated power supply, sensor signal circuit of linear actuator displace and wheel speed, and communication circuit were designed, too; The drive circuit of linear actuator was drove by motor special driver; Serial communication was adopted as communication circuit to realize communication between PC and the vehicle. On software, A/D conversion program of single chip, pulse capture program and related register configurations process were compiled.Thirdly, the upper machine monitor routine of electrical controlled brake system was designed on Lab VIEW and the communication between controller and computer was realized, which facilitate display of experimental date, graph drawing, dynamic compare and full automation of data acquisition.In order to testify reliability of hardware and software in electrical controlled brake system, the test was carried out on saddle piece, including relationship among pedal angle, displacement of linear actuator and wheel speed. The test result indicates that the performance of hardware is good, steady and reliable and the effect of software control meets the design demand. Therefore, the way for loading test was paved by the hardware and software. |
