Method for measuring rotating speed of automobile by using geophone in urban complex noise environment

Abstract

The invention relates to a method for measuring a rotating speed of an automobile by using a geophone in an urban complex noise environment. According to the method, the geophone is arranged on the ground of an automobile inspection site in an urban outdoor environment, the automobile is parked beside the geophone, when an automobile engine starts, generated vibration signals are coupled to the ground through wheels to form Rayleigh waves, and the Rayleigh waves are received within a certain range away from the wheels through a geophone so that speed measurement can be achieved. As the automobile inspection site is outdoor, the mobility of the inspected automobiles is greatly improved, the position of the geophone does not need to be adjusted no matter how many automobiles are continuouslydetected, the personnel operation is reduced, and the measurement efficiency is greatly improved. The method is efficient in automobile rotating speed measurement and simple in operation, only needsto drive the automobile to a designated position without adjusting positions of the measuring device and the automobiles, can continuously measure multiple automobiles in a short time, and at least doubles the measuring efficiency.

Description

technical field [0001] The invention relates to a method for measuring the rotational speed of automobiles in vehicle engineering, in particular to a method for measuring the rotational speed of automobiles by using a seismometer in an urban complex noise environment. Background technique [0002] In order to effectively ensure safe driving, automobiles need to conduct regular vehicle engine performance testing at the vehicle inspection agency. Automotive engine performance testing can evaluate the health status of the vehicle engine, timely investigate vehicle safety hazards, and reduce the occurrence of traffic accidents. Due to the limited number of vehicle inspection agencies and the large and sharp increase in the total number of vehicles in my country, the number of inspections by vehicle inspection agencies often exceeds the maximum capacity of a single day's inspection of vehicles. The huge number of inspections increases the work intensity and difficulty of vehicle i...

AI Technical Summary

Problems solved by technology

It is difficult for testers to evaluate the background noise level and noise stability in the measurement environment based on experience alone, and high noise level or noise instability will directly lead to inaccurate or even unreliable measurement results; After coupling into the ground, the energy attenuation is relatively large. In addition, there are human interferences with strong energy and strong randomness in the measurement environment in the city, such as people walking interference and long-distance vehicle driving interference. The energy of the collected useful signals is often less than Human interference makes it more difficult to reliably extract the speed of the car

For human interference, the document "Stochastic Modeling and Analysis of Land Seismic Exploration" is suitable for suppressing human interference in deserts, but since most of the vehicle speed measurement sites are on concrete ground, the energy of human interference in this environment is often many times that of useful signals , not suitable for suppressing the human interference of seismic signals in the urban environment, the literature "Research on the Noise Suppression Method of Weak Seismic Signals Based on RCSST and CNN" is suitable for the seismic exploration environment of multi-channel acquisition, not suitable for processing single-channel seismic signals in the vehicle inspection environment , In addition, the method usually used when suppressing strong noise is the median filter method. This method replaces the interference with the amplitude of the useful signal near the interference, but it will also weaken the useful signal in other periods, reducing the accuracy of the extraction speed.

[0008] Considering the existing vehicle speed measurement methods comprehensively, it is difficult to efficiently and reliably measure the vehicle speed within a period of time in the complex urban vehicle inspection environment

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