CN-121998919-A - Method for calculating rut depth by utilizing one-dimensional persistent coherence

CN121998919ACN 121998919 ACN121998919 ACN 121998919ACN-121998919-A

Abstract

The invention discloses a method for calculating rut depth by utilizing one-dimensional persistent coherence, and relates to the technical field of road defect detection. The logic is meticulous, the data processing effect is good, and the track depth can be accurately obtained. The technical scheme of the invention includes that the method comprises the following steps of 1, obtaining a pavement three-dimensional picture through laser scanning, slicing along the width direction, 2, finding out a topological structure for each slice through persistent coherence, 3, selecting a required 0-dimensional coherence vanishing position, setting a standard for eliminating source noise, 4, drawing a virtual line between the 0-dimensional coherence vanishing positions arranged in the step 2 after the noise is eliminated in the step 3, calculating the maximum height between the virtual line and the slice between the step 1, establishing rules for drawing straight lines based on definition of a straight line method and an envelope method respectively, and calculating the maximum height of the slice between the virtual line and the step 1. The invention can make the acquired data more accurate.

Inventors

ZHENG JIAXI
SHI WEIBIN

Assignees

伟乐科技集团有限公司

Dates

Publication Date: 20260508
Application Date: 20260109

Claims (3)

1. A method for calculating rut depth using one-dimensional persistent coherence, comprising the steps of: Step 1, obtaining a pavement three-dimensional picture by using laser scanning, slicing along the width direction, rescaling an image, and shrinking the image through slicing; Step 2, finding out a topological structure by using persistent coherence for each slice, calculating by using a one-dimensional image slice, considering only 0-dimensional coherence, wherein the 0-dimensional coherence is applied in one dimension, and birth and vanishing points are one-dimensional points; step 3, selecting a required 0-dimensional coherent vanishing position, and setting a standard for eliminating the source noise, wherein a depth threshold value, namely the depth difference of a 0-dimensional coherent death position, is set on the 0-dimensional coherent vanishing position; And 4, after the noise is eliminated in the step 3, drawing a virtual line between 0-dimensional coherent vanishing positions arranged in the step 2, calculating the maximum height between the virtual line and the slice between the step 1, establishing rules for drawing the straight line based on the definition of a straight line method and an envelope method respectively, and calculating the maximum height of the slice between the virtual line and the step 1.
2. A method for calculating rut depth using one-dimensional persistent coherence according to claim 1, wherein 0-dimensional coherence vanishing positions are arranged from left to right based on a straight line method, then a virtual line between two points is found in the vanishing positions, then only the point where the maximum height of the slice between the virtual line and step 1 is larger than a threshold value is taken, and finally the maximum height of the slice between the virtual line and step 1 is calculated.
3. A method for calculating rut depth using one-dimensional persistent coherence according to claim 1, wherein the highest point is found based on the envelope method, then the 0-dimensional coherence vanishing positions of the minimum slopes of the left and right sides are found in continuous iteration, the points are connected to form pseudo lines for calculating the virtual rut depth, and finally the maximum height of the slice between the virtual lines and step 1 is calculated.

Description

Method for calculating rut depth by utilizing one-dimensional persistent coherence Technical Field The invention relates to the technical field of road defect detection. Background Rutting is the gradual formation of longitudinal belt grooves on asphalt pavement under repeated rolling of vehicle tires (particularly in high temperature seasons) due to the flow and compaction deformation of asphalt mixture, which usually occurs on heavy traffic lane tread. The rut depth is the maximum vertical height difference between the bottom of the grooves and the original road surface not affected by ruts. It is a key index for measuring road pavement structure performance and use quality. Too great rut depth not only affects the beautiful appearance of the road, but also brings a series of serious problems: firstly, the safety risk of driving, and the easy ponding in the rut during rainy days, which leads to the occurrence of 'water slip' during high-speed driving of the vehicle, and the reduction of the control stability and the lengthening of the braking distance. Secondly, the comfort is reduced, and the vehicle can generate severe jolt when running on a rut road surface, so that the driving comfort is affected. Thirdly, the pavement damage is accelerated, namely, the drainage in the rut grooves is not smooth, water can permeate and erode the pavement base layer, the pavement structural strength is further weakened, and other diseases such as pit grooves, looseness and the like can be possibly caused. Accordingly, how to accurately obtain the rut depth for representing the structural performance and the use quality of the road pavement is a technical problem which is solved by the person skilled in the art. In particular, the rut depth is the depth of the pit at the tread band, and the key to obtain the rut depth is how to define this "pit datum". There are two common conventional methods for calculating rut depth, which are fundamentally different in the manner in which the reference surfaces are defined. The method is a linear reference method, which is a more traditional and visual method and is used in early manual measurement and partial simple systems, and the core idea is that the reference plane of the rut pit is defined as a simple straight line. This line typically connects the raised portions on either side of the tread band. The calculation steps are as follows: And 1, determining a reference straight line, namely manually or automatically determining two points on the acquired road surface cross section curve. These two points are typically located at the highest points of the ridge on both sides of the rut groove (points a and B). And 2, connecting a datum line, namely connecting the two points by using a straight line, wherein the straight line is the datum for calculating the rut depth. And 3, measuring the maximum vertical distance, namely measuring the vertical distance from the reference straight line to the lowest point of the rut groove, wherein the distance is the rut depth. The envelope method is a more advanced calculation method which is more in line with engineering practice, and is a standard method commonly adopted by the automatic detection equipment (such as a laser section meter) at present; the method considers that ruts are formed by lateral flow of materials, and the concave reference surface of the ruts should not be a simple straight line, but a virtual line which can simulate the original flat road surface before rut deformation occurs. This virtual line is the "envelope". The calculation steps are as follows: step 1, obtaining a road surface cross section curve, namely firstly, obtaining a complete road surface cross section elevation curve perpendicular to the driving direction through a high-precision sensor. This curve is rugged. And 2, generating a moving reference envelope curve, namely simulating a virtual ruler with a fixed length by a computer, and rolling from one end of the road surface curve to the other end of the road surface curve by being closely attached to the highest point of the curve. During rolling, the straight ruler forms a smooth curve which is always tangent to the highest point of the road surface, and the curve is an envelope curve. It effectively "ignores" rut-formed grooves. And step 3, calculating the maximum vertical distance, namely finding the maximum vertical distance between the envelope line and the original pavement curve in the whole measuring range. This maximum vertical distance is the rut depth. At present, in order to manage and maintain a road, the rut depth needs to be detected regularly, but the two conventional methods obviously have a plurality of remarkable defects. Firstly, the subjectivity is strong, the accuracy is poor, the lowest point of a rut and the highest point of a pavement are difficult to accurately judge by human eyes, the measurement result is seriously dependent on personal experience, and different detection person