2013-03-14 10:15:26 - Analysis of the cause and reason of car rearview mirror jitter
Exterior automotive rearview mirror is one of the important active safety devices, which help drivers to get the external environment information from both the two sides and the rear of the car, it is also the important automobile driving safety tool. In the car driving process, the road excitation, engine and drivetrain vibration will be caused by the vibration of the body, and may result in the rear-view mirror jitter. The severe jitter rear visibility, lead to driver errors of judgment and thus lead to accidents. According to the literature, our country because of the rear-view mirror design manufacturing defects caused traffic accidents accounted for 30% of the traffic accident, and the United States the proportion of 20%, especially on
the highway, this proportion is as high as 70%. Therefore, the rear-view mirror in addition to meet the requirements of the relevant regulations and standards, reasonable choice of the radius of curvature of the mirror size, installation location, you must pay attention to the dynamic characteristics of the rear-view mirror.
2 issues of the proposed
Found in the road during the experiment in a passenger car: the rear-view mirror is not only serious jitter in the idle condition occurred, and the high speeds and rough road driving significant jitter. Obscure the driver’s field of view, not only the driver could easily lead to eye fatigue, and can not be timely and accurate judgment on both sides and the rear of the case, there is a big security risk. To solve this problem, this paper carried out the analysis and improvement.
3 Experimental Modal Analysis
Test on the vehicle, in order to obtain the real working conditions of the rear-view mirror, the dynamic characteristics of the test rearview mirror when hammering incentive. Experimental data acquisition front-end, LMS SCADIII, hammer the the PCB company’s HEV200 sensor PCB company’s three-way acceleration sensor, and data analysis of processing software using Test.LAB 9 of the experiment.
Data collection cut-off frequency of 512Hz, the frequency resolution of 0.5Hz:
Be seen from the test results, the the rearview mirror modal frequency is low, it is easy to be inspired by the engine, the transmission system and the road is an important reason rearview mirror jitter.
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