The Analysis Of Automobile Static And Dynamic Brake

Automobile braking performance in GB7258-2004regulation has specific requirements inour country, especially; the number of production and purchase is increasing at present in ourcountry. How to guarantee the safty performance of the car has become an important topic whichmust be sloved in the whole society. Automobile brake system detection is adapted to the realityof China; automobile brake system can ensure the brake qualification of the cars when they arein the factory. China’s automobile manufacturers must be carried out the automobile brakingperformance test. Our country has been detecting by the road test. Although the road test cantruly reflect the actual vehicle braking performance, big risk in operation, high demends in thedetection field and personnel, and large judgment error in the fault location. Our automobilebrake equipments are developed on the basis of foreign testing equipment. Since the1960s, ourcountry gradually introducing foreign advanced system dynamic test bench instead of road testfor automobile brake performance test. Brake test machine cover a small eaer, and has high costperformance, good testing repeatability. At present, it has been wide used in each big automobilefactory and testing station in our country.This paper analyzed the force situation of automobile brake, the principle of Antilockbraking system, the principles and specifications of Jupiter-2000D Double Axles Brake testmachine and3700machine for Dynamic vehicle test. This paper mainly analyzed the principleof the brake test machines, plavement angle, roll surface adhesion coefficient, and tire surfacecondition and so on which influence on braking force test ability. And use Jupiter-2000D DoubleAxles Brake test machine and3700machine for Dynamic vehicle test for luxury andcomfortable model Yue Xiang V5and Rui Cheng cars which are made by Beijing changanautomobile factory, do static and dynamic braking force testing experiment respectively. Byforce data qcquisition and processing, we can get some coclusions that the same car betweendifferent tire cann’t fit the same function relation; they are very different cars’ static brakingforce fitting function relation and different cars’ dynamic one. The linear correlation coefficientmost are less than0.1, Fitting degree is rather poor. Car static front wheel braking force is aboutthree times as much as dynamic, Rear wheel static braking force is about dynamic2times. Theyhave small difference in the resistance against and braking force balance, and all can meet thenational standard. So Dynamic braking test machine can’t satisfy the requiremen of GB7258-2004.Finally,I analyzed the influence factors of the brake test in the process, and put forward Suggestions forimprovement.