路试充分发出平均减速度可取信范围分析  

The Admissible Range of MFDD Value Base on D'Alembert Principle

作　　者：王建军[1] 潘少猷[1] 陈建国[1] 

机构地区：[1]司法部司法鉴定科学技术研究所,上海200063

出　　处：《中国司法鉴定》2014年第2期80-82,共3页Chinese Journal of Forensic Sciences

摘　　要：当我们使用便携式制动性能测试仪来检验涉案车辆制动性能,为什么有时获得的充分发出的平均减速度（MFDD,mean fully developed deceleration）值会大于重力加速度g,这些较大的MFDD值与《便携式制动性能测试仪校准规范》中的测量范围是否相冲突,这些检测值在车速等运算中是否可以被采信,路试检验MFDD的有效范围是什么,鉴定业界对这些问题有着诸多争议和不同答案。本文旨在对路面摩擦系数进行讨论,并利用达朗贝尔原理建立车辆制动受力模型,从而证明高于g的充分发出的平均减速度在路试检验中可以成立,并确认了该值的可以取信范围0~l1h×g。Abstract： Why is the mean fully developed deceleration （MFDD） value sometimes greater than gravitational acceleration by the vehicle decelerometer during braking performance test？ Is this value in conflict with Calibration Specification for Portable Braking Performance Tester for Motor Vehicle？ Can this value be applied in vehicle speed estimation？ What is the effective range of MFDD value？ There are controversies and different understandings upon these confused issues among forensic experts. This article discussed the road surface friction coefficient, and established a vehicle braking process dynamics model to solve the present puzzles. The admissible range of MFDD was confirmed as O-l1/h×g,which shows the MFDD value greater than g ispossible in the braking performance test.

关 键 词：摩擦系数 充分发出的平均减速度 取信范围 车速 

分 类 号：U491.3[交通运输工程—交通运输规划与管理]