Correlation between residual speedometer needle reading and impact speed of vehicles in traffic accidents.

In actual traffic accidents, a phenomenon is observed where the speedometer needle jams at a certain value after the impact. Using the residual reading of the speedometer, we may infer the approximate vehicle speed while the impact occurred. Based on the function of typical speedometer, the impact characteristic and damage mechanism of vehicles, this paper describes the research of how the speedometer needle stops during accidents and its failure modes. According to the statistics of thirty specific traffic accident cases containing residual speedometer needle readings, we obtain and summarize the characteristics and rules concerning the accidents and the related information. Furthermore, a typical accident case is analyzed by in-depth level. The results reveal that for the accident vehicles with electronic speedometers, there is a strong correlation between the residual reading of the speedometer and the real vehicle impact speed. The conclusions may provide a new effective method and reference for accident reconstruction and the estimation of vehicle speed. [ABSTRACT FROM AUTHOR]