Train velocity measuring system and velocity measuring method through track proximity switches

Abstract

The invention relates to the technology of track traffic, in particular to a train velocity measuring system and velocity measuring method through track proximity switches. The velocity measuring system comprises two sets of proximity switches, a single chip microcomputer and an upper computer, wherein the proximity switches are used for detecting the marching direction and marching speed of a train, the single chip microcomputer is connected with the proximity switches and transmits character string information to the upper computer after receiving level signals transmitted by the proximity switches, and the upper computer is connected with the single chip microcomputer, verifies the received information and then obtains the speed information and the direction information of the train through analysis. When the train passes through, the proximity switches arranged on a track in the train coming direction can generate TTL levels, the single chip micro computer receives the level signals and judges the direction and speed of the train based on algorithm induction time difference, and the upper computer verified the received information and then obtains the speed information and the direction information of the train through analysis. The train velocity measuring system and velocity measuring method through the track proximity switches effectively avoids the defects, and has the advantages of being precision in velocity measuring range, accurate in measurement, small in influence by environment, capable of effectively ensuring the fact that the speed of the train is controlled within the range of 0.1KM/H and the like.

Description

technical field [0001] The invention relates to rail transit technology, in particular to a train speed measurement system with a rail proximity switch and a speed measurement method thereof. Background technique [0002] At present, the technical means used in the field of measuring the precise speed and direction of locomotives can be divided into three technical means: (1) Use ultrasonic radar to measure speed. The volume is large, the precision is low, and because the measured value is an analog quantity, it must be A / D converted before it can be read into the computer. Speed ​​radar mainly uses the principle of Doppler effect: when the target approaches the radar antenna, the frequency of the reflected signal will be higher than the frequency of the transmitter; conversely, when the target moves away from the antenna, the frequency of the reflected signal will be lower than the transmission probability . In this way, the relative speed between the target and the radar...

AI Technical Summary

Problems solved by technology

Disadvantages: easily affected by the weather, such as wind, rain, thunder, lightning, fog and snow, etc., low precision, and is greatly affected by the surrounding environment. Moreover, when the locomotive whistles, the signal will be strongly interfered, and there will be a large abrupt change, which requires software noise reduction. Accurate (2) The disadvantage of using passive magnetic steel for speed measurement is that when the speed of the locomotive is low, the change of the magnetic field can hardly be sensed, and the output signal is very small. However, the speed of many locomotives in the locomotive maintenance workshop is below 5km / h, which is not applicable Locomotive running system; (3) Using active rail wheel sensors to measure speed, the disadvantage is that the electric locomotive has great interference with it, and it is easy to generate false action signals and the sensor is not sensitive, and the direction and speed are prone to errors

The image resolution of a single carriage collected by the cargo inspection station currently used can reach more than 8000*2048, and can clearly distinguish details. However, when the speed of conventional video and network cameras is above 20KM / H, clear and effective images cannot be captured. Line scan The unit has successfully solved this shortcoming; at present, the actual speed of the test truck passing through each cargo inspection station is between 1KM / H-120KM / H. If the speed deviation measured by the speed measurement system is more than 5%, the line scanning module is adjusted according to the speed. The image spliced ​​by scanning frames will be severely distorted and cannot be used for vehicle inspection

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