CN112461243B - A kind of inspection robot positioning method and system - Google Patents

Abstract

The invention discloses a positioning method of an inspection robot, which comprises the following steps: acquiring the length of a lead in a field of view of the inspection robot by adopting a sample with the same diameter as the lead; acquiring the distance between adjacent lines of the lead along the axial direction of the lead according to the length of the lead in the acquired field of view; the moving distance of the inspection robot is obtained according to the distance between adjacent lines of the wire along the axial direction of the wire and the number of the lines passed by the inspection robot to realize positioning, and the invention can realize accurate positioning of the inspection robot.

Description

Positioning method and system for inspection robot

Technical Field

The invention belongs to the technical field of power line inspection, and particularly relates to an inspection robot positioning method and system.

Background

Overhead conductors are important carriers for electrical energy transmission. The damage of the inside and the outside of the wire can cause the disconnection, and the safe and stable operation of the power transmission line and the safety of the surrounding public are seriously threatened. At present, an inspection robot crawls along a line and carries equipment such as a visible light camera, an infrared detector, an ultraviolet detector and even an X-ray machine to inspect a power transmission line, and the inspection robot is an important means for guaranteeing the safety of the line. In the inspection, the position of the inspection robot on the lead is determined, which is the premise of determining the defect position and formulating the next maintenance strategy. At present, the location of patrolling and examining the robot mainly adopts the encoder to connect at driving motor or directly contact with the wire, through rotating the number of turns with the motor and converting into the mileage, acquires the positional information of robot on the wire. However, the driving wheel or the encoder wheel of the inspection robot easily slips on the surface of the wire, so that a metering error is caused.

Disclosure of Invention

The invention aims to provide a positioning method and a positioning method for an inspection robot, which can realize accurate positioning of the inspection robot.

In order to achieve the purpose, the invention provides the following technical scheme:

in a first aspect, a method for positioning an inspection robot is provided, which includes:

acquiring the length of a lead in a field of view of the inspection robot by adopting a sample with the same diameter as the lead;

acquiring the distance between adjacent lines of the lead along the axial direction of the lead according to the length of the lead in the acquired field of view;

and obtaining the movement distance of the inspection robot according to the axial distance between adjacent lines of the wire and the number of the lines passed by the inspection robot to realize positioning.

Combine first aspect, it is further, the adoption specifically is with the length of wire in the wire isodiametric sample acquisition inspection robot visual field:

selecting a long strip with the same diameter as the wire as a sample, wherein the length of the long strip is greater than that of the wire in the field of view of the inspection robot, and marking the length of the long strip with a length size;

selecting an inspection robot the same as that in actual inspection, placing the inspection robot on a long object, and keeping the directions of a camera of the inspection robot and the camera in actual inspection consistent;

and (3) enabling two ends of the marked long article to exceed the boundary of the field of view of the inspection robot, shooting an image of the inspection robot through a camera of the inspection robot, and obtaining the actual length L of the long article in the field of view according to the image.

With reference to the first aspect, further, the obtaining, according to the obtained length of the wire in the field of view, a distance between adjacent lines of the wire along the axial direction of the wire specifically includes:

shooting an image on a lead in a static state through a camera of the inspection robot, and converting the image into a gray scale image;

reading the gray value of the image along the axial direction of the lead to generate a gray value change curve;

reading the number n of the abrupt change points in the change curve, and recording the axial pixel position A of the wire corresponding to each abrupt change point₁、A₂、A₃、A₄……An；

Calculating the distance between adjacent lines of the wire along the axial direction of the wire according to the formula (2), wherein the formula (2) is as follows:

s＝d×(An-A₁)/(n-1) (2)；

wherein s is the actual distance between adjacent lines along the axial direction of the wire, and d is the actual size of each pixel point along the length direction of the wire.

Combine the first aspect, it is further, obtain the movement distance who patrols and examines the robot according to the adjacent line of wire along the axial interval of wire and the line number that patrols and examines the robot and pass through and realize the location specifically do:

m monitoring points are selected along the radial direction of a lead in the view field of the inspection robot, and the number of m is preferably more than or equal to 3 in order to ensure the precision.

Converting a view field image of the inspection robot into a gray level image, and monitoring the gray level value of each monitoring point in real time in the moving process of the inspection robot;

when the gray value of a certain monitoring point has a minimum value of mutation, the number of lines passing through the monitoring point is increased by 1, and accordingly, the mutation times of m monitoring points are x1 and x2 … … xm respectively;

calculating the current distance P of the inspection robot relative to the initial position according to the formula (3);

P＝s×(Max[x1、x2.......xm]-1) (3)

wherein s is the actual distance between adjacent lines along the axial direction of the wire.

With reference to the first aspect, further, the method for calculating the actual size d, represented by each pixel point, along the length direction of the wire includes:

reading the number N of pixels of the inspection robot view field picture along the axial direction of the lead, calculating according to the formula (1) to obtain the actual size of a single pixel point along the length direction of the lead,

d＝L/N (1)。

in a second aspect, a positioning system for an inspection robot is provided, comprising:

the field-of-view wire length acquisition module is used for acquiring the length of a wire in a field of view of the inspection robot by adopting a sample with the same diameter as the wire;

the line spacing calculation module is used for acquiring the spacing between adjacent lines of the wire along the axial direction of the wire according to the acquired length of the wire in the field of view;

and the positioning module is used for obtaining the movement distance of the inspection robot according to the axial distance between adjacent lines of the wire and the number of the lines passed by the inspection robot to realize positioning.

The beneficial technical effects are as follows: the invention discloses an inspection robot positioning method based on an inspection robot video image, which finds out a gray-scale catastrophe point, namely lines on a wire, by detecting the gray-scale change condition of a certain fixed point in the inspection robot video image without depending on an encoder, and further accurately obtains the position of the inspection robot relative to a starting point according to the line distance of the wire and the number of the lines passed by the robot, thereby reducing the positioning error caused by slipping.

Drawings

FIG. 1 is a schematic diagram of the spacing of the lines on the wire of the present invention;

FIG. 2 is a schematic diagram showing the variation of gray scale of a conductive line along the axial direction;

FIG. 3 is a schematic view of monitoring points of the inspection robot moving on the wire;

fig. 4 is a gray scale diagram of a wire as a sample in the present invention.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

As shown in fig. 1 to 4, there is provided a method for positioning an inspection robot, including the steps of:

step one, adopting a sample with the same diameter as the lead to obtain the length of the lead in the field of view of the inspection robot, and specifically comprising the following steps:

s11, selecting a long strip (which can be a wire or a bar) with the same diameter as the wire as a sample, wherein the length of the long strip is larger than that of the wire in the field of view of the inspection robot, and marking the length of the long strip with a size;

s12, selecting the same inspection robot as the inspection robot in the actual inspection, placing the inspection robot on the long object, and keeping the directions of the camera of the inspection robot and the camera in the actual inspection consistent;

and S13, enabling the two ends of the marked long article to exceed the boundary of the field of view of the inspection robot, shooting the image through a camera of the inspection robot, and obtaining the actual length L of the long article in the field of view according to the image.

Step two, obtaining the distance between adjacent lines of the lead along the axial direction of the lead according to the obtained length of the lead in the field of view, and specifically comprising the following steps:

s21, shooting an image by the inspection robot in a static state on a lead, and converting the image into a gray scale image;

s22, reading the gray value of the image along the axial direction of the lead to generate a gray value change curve;

s23, reading the number n of the abrupt change points in the change curve, and recording the axial pixel position A of the wire corresponding to each abrupt change point₁、A₂、A₃、A₄……An；

S24, calculating the distance between the adjacent lines of the conducting wire along the axial direction of the conducting wire according to the formula (2), wherein the formula (2) is as follows:

s＝d×(An-A₁)/(n-1) (2)；

the gray scale variation value of each pixel in the direction parallel to the axis of the conductive line is read as shown in fig. 3. From which the grey scale variation is seen. The number of points with abrupt change in gray scale is 13, and the pixel positions in the axial direction on the image are 142, 353 and 572 … … 3906, respectively, and s (3906-.

Wherein s is the actual distance between adjacent lines along the axial direction of the wire, and d is the actual size of each pixel point along the length direction of the wire. The wire lines 1 are formed by aluminum wires spirally wound on the surface of the wire, and the lines are gaps between two aluminum wires, so that the gaps are darker and the aluminum wires are more colorful, the gray level change curve is in a pulse fluctuation shape, and the gaps are abrupt points.

The acquisition method of d comprises the following steps: and reading the number N of pixels of the inspection robot view field picture along the axial direction of the wire, and calculating according to the formula (1) to obtain the actual size of the single pixel point along the length direction of the wire.

d＝L/N (1)

The wire length shown in fig. 4 is 253mm, the normal image pixel length value is known as 3983, and the actual length of a single pixel in the field of view is 253/3983.

Step three, obtaining the movement distance of the inspection robot according to the axial distance of the adjacent lines of the wire along the wire and the number of the lines passed by the inspection robot to realize positioning, and the concrete steps are as follows:

s31, selecting m monitoring points (the monitoring points are shown as the position of an X in the figure 3) along the radial direction of the lead at any axial position of the lead in the visual field of the inspection robot, and taking the value of m to be not less than 3 in order to ensure the precision.

S32, converting the view field image of the inspection robot into a gray scale image, and monitoring the gray scale value of each monitoring point in real time in the moving process of the inspection robot;

s33, when the gray value of a certain monitoring point has a minimum value of mutation, the number of lines passing through the monitoring point is added with 1, and accordingly the mutation times of m monitoring points are x1 and x2 … … xm respectively;

calculating the current distance P of the inspection robot relative to the initial position according to the formula (3);

P＝s×(Max[x1、x2.......xm]-1) (3)

as shown in fig. 3, when the inspection robot moves, relative motion occurs between the camera on the robot and the wire, which is equivalent to that the monitoring points move to the right vertical line position along the horizontal line, 10 extreme points are obtained from the uppermost monitoring point, 11 extreme points are obtained from the middle monitoring point, 11 extreme points are obtained from the lowermost monitoring point, and the actual moving distance is about P ═ Max (10,11,11) -1] × 19.92 ═ 199.2 mm. The error is at most 1 aluminum strand gap spacing, i.e., 19.92mm, regardless of the length of the wire.

Example 2

Provided is an inspection robot positioning system, including:

the field-of-view wire length acquisition module is used for acquiring the length of a wire in a field of view of the inspection robot by adopting a sample with the same diameter as the wire;

the line spacing calculation module is used for acquiring the spacing between adjacent lines of the wire along the axial direction of the wire according to the acquired length of the wire in the field of view;

and the positioning module is used for obtaining the movement distance of the inspection robot according to the axial distance between adjacent lines of the wire and the number of the lines passed by the inspection robot to realize positioning.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims (4)

1. a patrol robot positioning method, is characterized in that, comprises: The length of the wire in the field of view of the inspection robot is obtained by using a sample with the same diameter as the wire. Specifically, a long object with the same diameter as the wire is selected as the sample, and its length is greater than the length of the wire in the field of view of the inspection robot. good length dimension marks; Select the same inspection robot as in the actual inspection, place it on the long object, and keep the camera of the inspection robot in the same direction as the camera in the actual inspection; The two ends of the marked long object are beyond the field of view boundary of the inspection robot, and its image is captured by the camera of the inspection robot, and the actual length L of the long object in the field of view is obtained according to the image; The distance between adjacent lines of the wire along the axis of the wire is obtained according to the length of the wire in the obtained field of view. Specifically, the camera of the inspection robot takes an image on the wire in a static state, and converts the image into grayscale. picture; Read the gray value of the image along the wire axis to generate a gray value change curve; Read the number n of mutation points in the change curve, and record the corresponding wire axis pixel positions A ₁ , A ₂ , A ₃ , A ₄ ...... An of each mutation point; According to formula (2), the distance between adjacent lines of the wire along the axis of the wire is calculated, and formula (2) is as follows: s=d×(An-A ₁ )/(n-1) (2); Among them, s is the actual spacing of adjacent lines along the axis of the wire, and d is the actual size along the length of the wire represented by each pixel; According to the distance between adjacent lines of the wire along the axis of the wire and the number of lines passed by the inspection robot, the movement distance of the inspection robot can be obtained to realize positioning. Specifically, m monitoring points are selected along the radial direction of the wire in the field of view of the inspection robot. ; Convert the field of view image of the inspection robot into a grayscale image, and monitor the gray value of each monitoring point in real time during the movement of the inspection robot; When the gray value of a monitoring point has a minimum value of sudden change, the number of lines passing through the monitoring point is added by 1. According to this, the mutation times of m monitoring points can be obtained as x1, x2....xm ; Calculate the current distance P of the inspection robot relative to the starting position according to formula (3); P=s×(Max[x1, x2....xm]-1) (3) Among them, s is the actual spacing of adjacent lines along the wire axis; The ridges are formed by helically wound wires on the surface of the wire, ie the gaps between the two wires. 2. The inspection robot positioning method according to claim 1, wherein the calculation method of the actual size d along the wire length direction represented by each pixel point is: Read the field of view picture of the inspection robot, the number of pixels N along the axis of the wire, and calculate the actual size along the length of the wire represented by a single pixel point according to formula (1). d=L/N (1). 3 . The positioning method for an inspection robot according to claim 1 , wherein the number m of monitoring points is greater than or equal to 3. 4 . 4. An inspection robot positioning system, comprising: The field of view wire length acquisition module is used to obtain the length of the wire in the field of view of the inspection robot by using a sample with the same diameter as the wire. The length of the wire in the field, make the length dimension mark for it; Select the same inspection robot as in the actual inspection, place it on the long object, and keep the camera of the inspection robot in the same direction as the camera in the actual inspection; The two ends of the marked long object are beyond the field of view boundary of the inspection robot, and its image is captured by the camera of the inspection robot, and the actual length L of the long object in the field of view is obtained according to the image; The pattern spacing calculation module is used to obtain the distance between adjacent lines of the wire along the axial direction of the wire according to the length of the wire in the obtained field of view, specifically: specifically: taking a picture of a static state on the wire through the camera of the inspection robot image, and convert the image to grayscale; Read the gray value of the image along the wire axis to generate a gray value change curve; Read the number n of mutation points in the change curve, and record the corresponding wire axis pixel positions A ₁ , A ₂ , A ₃ , A ₄ ...... An of each mutation point; According to formula (2), the distance between adjacent equal-width lines of the wire along the axis of the wire is calculated, and formula (2) is as follows: s=d×(An-A ₁ )/(n-1) (2); Among them, s is the actual spacing of adjacent equal-width lines along the axis of the wire, and d is the actual size along the length of the wire represented by each pixel; The positioning module is used to obtain the movement distance of the inspection robot according to the distance between adjacent lines of the wire along the axial direction of the wire and the number of lines passed by the inspection robot to achieve positioning, specifically: in the field of view of the inspection robot along the radial direction of the wire Select m monitoring points; Convert the field of view image of the inspection robot into a grayscale image, and monitor the gray value of each monitoring point in real time during the movement of the inspection robot; When the gray value of a monitoring point has a minimum value of sudden change, the number of equal-width lines passed by the monitoring point is added by 1, and the number of sudden changes of m monitoring points can be obtained as x1, x2...xm respectively; Calculate the current distance P of the inspection robot relative to the starting position according to formula (3); P=s×(Max[x1, x2....xm]-1) (3) Among them, s is the actual spacing of adjacent equal-width lines along the wire axis; The ridges are formed by helically wound wires on the surface of the wire, ie the gaps between the two wires.

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