Vehicle tread measurement method based on stereo vision and laser

Abstract

The invention provides a wheel distance measuring method based on stereo vision and laser, which uses a stereo vision laser measuring system to obtain relative measuring parameters. The method uses a digit camera to shoot laser pattern projected on the tyre crown, uses image processing method to extract laser pattern target, uses stereo match algorism and three-dimension rebuild algorism to obtain laser pattern stereo point. And the invention projects the laser pattern stereo point on a simulated plane of the laser pattern, uses the projected point to generate a two-dimension curvature, to calculate out an extreme point of the two-dimension curvature, while the extreme point is relative to the tangential point of the tyre crown. And the invention uses one tangential point at inner tyre crown and at least three tangential points at outer tyre crown to simulate a tangential plane to calculate out the central plane of tyre. And the invention calculates out the distance between the cross lines of the central planes of left and right tyres on one shaft and the wheel support plane to obtain the vehicle wheel distance.

Description

technical field [0001] The invention belongs to the technical field of visual measurement, in particular to a vehicle wheelbase measurement method based on stereo vision and laser. Background technique [0002] The national standard "Terms and Definitions of Automobiles and Trailers and Their Definitions Vehicle Dimensions" (GB / T 3730.3-1992) defines the wheelbase as, assuming that the two points A and B are the vertical plane of the vehicle support plane W passing through the wheel axes at both ends of the same axle The intersection of the intersection line A with the center plane of the wheel and the vehicle support plane W, the distance between A and B is the vehicle wheel base. Wherein the vehicle supporting plane W is a flat, solid horizontal plane for supporting the wheels. The schematic diagram of the wheelbase of the vehicle is shown in Figure 1, where L in the figure represents the wheelbase of the vehicle. [0003] At present, the methods of vehicle wheelbase mea...

AI Technical Summary

Problems solved by technology

This method requires additional sensors to measure the speed and time of the vehicle, and the angle between the sensor and the vehicle must be calibrated in advance, so the measurement structure is relatively complicated, and the final measurement structure is affected by many other factors

In addition, the measurement principle of this method determines that the final vehicle wheelbase accuracy is low, and different types of tires have a greater impact on its measurement accuracy

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