the development of passenger car braking performance simulation software: preparation of passenger car braking performance simulation calculation software; 2 r&d bus braking test system: developing a passenger car braking performance testing device, used for the dynamic real time test the installation of pneumatic brake system of passenger cars in the braking process of brake performance, brake speed, speed, braking distance and braking time, test the wheel brake pressure change curve and the brake pedal and brake pressure response lag time process sequence. The system has the basic function such as real-time testing, test report is automatically generated.