汽车滚筒反力式制动台测量结果的影响因素分析

Analysis of influencing factors on testing results of vehicle roller anti-force brake testing platform

汽车制动性能台试检验已成为检测汽车制动系统技术状况、保障汽车运行安全的主要技术手段.描述了新型滚筒反力式汽车制动检验台的机械结构,并对检验台进行了动力学分析,对车辆轴荷、滚筒高度差、安置角、滚筒表面附着系数、轮胎气压、制动力信号采样频率和司机驾驶操作对制动检验台检测精度的影响规律进行了测试分析.实车测试结果表明:调节滚筒轴距和改变轮胎气压对制动力检测结果有显著影响,在滚筒轴距由(470+26)mm增加到(470+150)mm时,当量附着系数由0.636增加到0.746;轮胎气压由0.15 MPa增加到0.35 MPa时,其最大制动力下降了25.8%;为确保制动力检测结果的准确性,应保证滚筒轴距和轮胎气压满足测试要求.

The vehicle braking performance platform test has become the main technical approach tocheck the technical situation of vehicle braking system and ensure the safety of vehicle operation. Themechanical structure of a new vehicle roller anti-force brake testing platform was described , and thekinetic analysis of the t st platform was conducted. The effects of axle load, roller height setting angle , roller surface adhesion coefficient , tire pressure , sampling frequency of braking signal and driver driving operation on the test precision of brake testing platform were tested and analyzed. The results of field vehicle test show that roller distance adjustment and tire pressure change have significant impact on the braking dynamic test results. When the roller distance is increased from （470 ＋26） mm to （470 ＋ 150 ） mm , the equivalent adhesion coefficient increases from 0 . 636 to 0. 746. When the tirepressure is increased from 0. 15 MPa to 0.35 MPa , the maximal braking force is decreased by 25. 8%. To obtain accurate test result of braking force , the test requirements of roller distance and tire pressure should be satisfied in real application.