CN107560545B - Contact line abrasion automatic measuring instrument and measuring method based on machine vision - Google Patents
Contact line abrasion automatic measuring instrument and measuring method based on machine vision Download PDFInfo
- Publication number
- CN107560545B CN107560545B CN201710918729.0A CN201710918729A CN107560545B CN 107560545 B CN107560545 B CN 107560545B CN 201710918729 A CN201710918729 A CN 201710918729A CN 107560545 B CN107560545 B CN 107560545B
- Authority
- CN
- China
- Prior art keywords
- contact line
- wearing
- abrasion
- width
- wearing surface
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
- 238000005299 abrasion Methods 0.000 title claims abstract description 49
- 238000000034 method Methods 0.000 title claims abstract description 30
- 238000003384 imaging method Methods 0.000 claims description 17
- 238000001514 detection method Methods 0.000 claims description 11
- 230000003287 optical effect Effects 0.000 claims description 6
- 238000012545 processing Methods 0.000 claims description 6
- 238000005259 measurement Methods 0.000 claims description 4
- 238000004891 communication Methods 0.000 claims description 3
- 238000004364 calculation method Methods 0.000 claims 1
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 230000008569 process Effects 0.000 description 10
- 230000008859 change Effects 0.000 description 8
- 238000004458 analytical method Methods 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000000691 measurement method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000003321 amplification Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000002542 deteriorative effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000006872 improvement Effects 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
Abstract
The invention relates to an automatic contact line abrasion measuring instrument and a measuring method based on machine vision, wherein the instrument comprises a shell with a handle on the side surface, and a window is arranged on the surface of the shell; the inside light emission unit that is provided with of shell, light emission unit send the light beam behind the reflection unit, through the window cover projection is on the contact line wearing and tearing face that is detected, the reflection light of contact line wearing and tearing face that is detected returns to the reflection unit along the original way, after the reflection unit, by telecentric lens receiving and formation of image, the formation of image is sent to the treater, and the treater is according to formation of image calculates contact line wearing and tearing face width, calculates corresponding contact line wearing and tearing volume according to the geometric relation between wearing and tearing face width and the wearing and tearing volume.
Description
Technical Field
The invention relates to a contact line abrasion automatic measuring instrument and a contact line abrasion automatic measuring method based on machine vision.
Background
The prior overhead contact system is mainly distributed in the railway field and the subway field, the flexible overhead contact system is mainly adopted in the railway field, the rigid overhead contact system is adopted in the subway field, the rigid overhead contact system has the greatest advantages of no axial tension, no possibility of wire breakage, relatively simple structure, small overhaul and maintenance workload and the like. At present, most subways in China use rigid contact networks, but as the running time increases, the arch gateway system between the flashlight arch and the contact line of a train in certain sections is poor, so that the phenomenon of serious local abrasion of the contact line is increasingly prominent, and the contact line is likely to be broken when the contact line is serious in abrasion, thereby further deteriorating the arch-network relationship.
Besides the difference in rigidity and flexibility between the contact line in the subway and the contact line in the railway field, there is a great difference in that the contact line in the subway needs to be clamped by a bus bar, the contact line needs to be detached from the bus bar for detection when the contact line in the subway is detected at present, and the contact method of a vernier caliper is used for detection.
Disclosure of Invention
Aiming at the defects existing in the prior art, the invention provides an automatic contact line abrasion measuring instrument based on machine vision, which can adopt a non-contact measuring mode to finish the detection of the contact line abrasion in the subway.
The technical scheme of the invention is as follows:
an automatic contact line wear measuring instrument based on machine vision, comprising:
a housing having a window;
the inside light emission unit that is provided with of shell, light emission unit send the light beam behind the reflecting unit, pass through the window and throw on the contact line wearing surface that is detected, the reflected light of contact line wearing surface that is detected returns to the reflecting unit along the original way, and the light beam is received and is imaged by the invariable lens group of magnification behind the reflecting unit, and the industry camera shoots the formation of image.
The lens group used in the invention has the characteristic of unchanged imaging magnification, and in the process of measuring the abrasion of the contact line, the object distance between the abrasion surface and the lens group is different due to the different abrasion amount of the contact line. The magnification of a general lens changes with the change of object distance, and is not suitable for accurately measuring the width of a wearing surface. The invention uses telecentric light path characteristic to ensure that the measuring result of the actual width of the wearing surface is not interfered by the change of the object distance.
The invention adopts the reflecting unit to play the role of folding the light path, effectively reduces the overall height of the contact line measuring instrument, and is convenient for the carrying and operation of measuring personnel.
Furthermore, a positioning block is arranged on one side of the surface of the shell, provided with a window, and used for being attached to the surface of the busbar of the fixed contact line, so that the posture of the instrument during measurement is maintained.
Further, the central axis of the light emitting unit coincides with the optical axis of the telecentric lens within a set range.
Further, the light emitting unit adopts a hollow surrounding light source.
Further, the camera system also comprises a processor connected with the industrial camera, wherein the processor adopts an embedded processor.
The invention also provides a contact line abrasion automatic measurement method based on machine vision, which comprises the following steps:
the light beam emitted by the light emitting unit is projected on the detected contact line wearing surface, the light beam is received and imaged by the telecentric lens after being reflected by the detected contact line wearing surface, the imaging is recorded, the width of the detected contact line wearing surface in the imaging image is obtained by utilizing an image detection algorithm, and the corresponding contact line wearing amount is calculated according to the geometric relationship between the wearing surface width and the wearing amount.
Further, the step of obtaining the detected contact line wearing surface width in the imaging image by using the image detection algorithm comprises the following steps:
binarizing the imaging image;
determining a connected domain belonging to the contact line wearing surface according to the binarized image;
fitting a contact line wearing surface boundary equation according to the connected domain, calculating the distance between the boundaries at two sides of the contact line wearing surface according to the boundary equation, and finally calculating the width of the contact line wearing surface by using the magnification coefficient of the telecentric lens.
Further, fitting a contact line wear surface boundary equation according to the connected domain includes:
and processing the profile of the contact line wearing surface communication domain by using a parallelogram approximation method to obtain coordinates of four vertexes of a quadrilateral, calculating linear equations of two side boundaries of the contact line wearing surface according to the four vertexes of the quadrilateral, obtaining a point set positioned in a set distance range around the linear equations, and fitting the contact line wearing surface boundary equation according to the point set.
Further, calculating the corresponding contact line wear amount according to the geometric relationship between the wear surface width and the wear amount includes:
and calculating the abrasion loss of the contact line by using a chord length bow height method according to the radius of the contact line.
Further, the method also includes calculating a contact wire residual height, a contact wire width and a wear percentage according to the contact wire wear amount.
The invention has the beneficial effects that:
the contact line abrasion measuring instrument provided by the invention is a non-contact type automatic measuring device, and has the advantages of high automation degree and high measuring precision in the measuring process.
Telecentric lenses used in the instrument have the characteristic of constant imaging magnification. In the process of measuring the contact line, the abrasion amount of the contact line is different, so that the object distance between the abrasion surface and the lens is also different. The magnification of a general lens changes with the change of object distance, and is not suitable for accurately measuring the width of a wearing surface. The invention uses telecentric light path characteristic to ensure that the measuring result of the actual width of the wearing surface is not interfered by the change of the object distance.
The reflection unit used in the instrument plays a role in folding the light path, can effectively reduce the overall height of the contact line measuring device, and is convenient for the measuring personnel to carry and operate.
The central axis of the surrounding type light source is basically coincident with the optical axis of the telecentric lens, and the installation mode ensures that the emergent light of the ring-shaped light source uniformly irradiates on the contact line wearing surface.
In the use process of the instrument provided by the invention, the positioning block of the measuring instrument is tightly attached to the subway line busbar, an industrial camera in the measuring device can clearly shoot an image of the wearing surface of the contact line, and the wearing value of the contact line can be obtained after analyzing and processing the image. In addition to the wear values, the measuring instrument can also obtain three important parameters, namely the contact line residual height, the contact line width and the wear percentage.
Drawings
FIG. 1 is a schematic diagram of the contact line wear measuring instrument of the present invention;
fig. 2 shows an example of the present invention.
The specific embodiment is as follows:
the invention is further illustrated by the following examples in conjunction with the accompanying drawings:
it should be noted that the following detailed description is illustrative and is intended to provide further explanation of the present application. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs.
It is noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments in accordance with the present application. As used herein, the singular is also intended to include the plural unless the context clearly indicates otherwise, and furthermore, it is to be understood that the terms "comprises" and/or "comprising" when used in this specification are taken to specify the presence of stated features, steps, operations, devices, components, and/or combinations thereof.
As mentioned in the background art, the contact line in the subway needs to be clamped by the bus bar, when the contact line in the subway is detected at present, the contact line needs to be detached from the bus bar, and the contact method of the vernier caliper is adopted for detection, so that the method is not strong in automation and low in efficiency, and therefore, a method for completing detection without detaching the contact line from the bus bar is necessary to be studied.
As shown in fig. 1, an exemplary embodiment of the present invention is a contact line abrasion automatic measuring instrument based on machine vision, which includes an instrument housing, a handle provided on a side surface of the instrument housing, and a viewing window provided on a side surface of the housing opposite to the handle.
The light emitting unit is arranged inside the shell, in the embodiment, an annular light source is adopted as the light emitting unit, and other hollow surrounding light sources can be adopted, so that the lens group with constant magnification is surrounded in the hollow area of the lens group. The outgoing light of the annular light source irradiates the contact line wearing surface through a window coverage on the instrument shell after passing through the reflecting unit, the wearing surface which is uniformly illuminated is imaged in the camera through a telecentric light path, and then an embedded processor is adopted to analyze and process the wearing surface image and obtain the width of the contact line wearing surface, so that the contact line wearing amount is calculated.
The embedded processor in this embodiment may also be an external processor that communicates wirelessly, and is not limited to the embedded processor.
In this embodiment, the reflecting unit adopts a reflecting mirror, but the reflecting unit is not limited to the reflecting mirror, and may be other optical elements having a reflecting function.
The lens group with constant magnification used in the embodiment is preferably a telecentric lens, and the telecentric lens has the characteristic of constant imaging magnification, and in the process of measuring the abrasion of the contact line, the object distance between the abrasion surface and the lens is different due to different abrasion amounts of the contact line. The magnification of a general lens changes with the change of object distance, and is not suitable for accurately measuring the width of a wearing surface. And by adopting a telecentric light path and utilizing the characteristic of unchanged imaging magnification, the measuring result of the actual width of the wearing surface can be ensured not to be interfered by the change of the object distance.
The reflector in this embodiment plays the folding effect of light path, can effectively reduce the holistic height of contact line measuring device, and the measuring personnel of being convenient for carries and operates.
The annular light source needs to be fixed on the device base, the central axis of the annular light source is basically coincident with the optical axis of the telecentric lens, and the installation mode can ensure that the emergent light of the annular light source uniformly irradiates on the contact line wearing surface.
As shown in fig. 2, an example of the present invention is provided, in which a positioning block is mounted on a housing of a metro contact line wearing device, and the positioning block can be tightly attached to a bus surface of a fixed contact line, so as to ensure a correct posture during measurement of an instrument. When the measuring device works, a measuring person closely attaches a positioning block of the measuring device to the bus bar of the subway line, and presses a measurement start button when the abrasion amount is required to be measured, so that a camera in the measuring device shoots an image of the abrasion surface of the contact line, and the abrasion amount value of the contact line can be obtained after the image is analyzed and processed.
When the instrument is used for measuring the contact line abrasion loss, the core is that an imaging image is used for analysis, and the contact line abrasion loss automatic measurement method based on machine vision comprises the following steps:
the light beam emitted by the light emitting unit is projected on the detected contact line abrasion surface in a covering manner, the light beam is received by the telecentric lens after being reflected by the detected contact line abrasion surface and imaged, the imaging is recorded by an industrial camera or other storage media, the width of the detected contact line abrasion surface in the imaging image is obtained by utilizing an image detection algorithm, and the corresponding contact line abrasion amount is calculated according to the geometric relationship between the abrasion surface width and the abrasion amount.
In this embodiment, an image detection algorithm is used to process the imaged image, and then the contact line abrasion loss is obtained, which includes the following steps:
(1) Performing binarization processing on the contact line image;
(2) Carrying out connected domain analysis on the binarized image, and determining a connected domain belonging to the contact line wearing surface according to the area characteristics of the connected domain;
(3) Processing the profile of the communication domain of the wearing surface by using a parallelogram approximation method, and obtaining coordinates of four vertexes of the quadrilateral;
(4) Preliminarily calculating linear equations L1 and L2 of the boundaries on two sides of the wearing surface according to four vertexes of a quadrilateral, and then respectively counting contour points with two linear distances smaller than 0.5 pixel to form point sets P1 and P2;
(5) And precisely fitting a wear surface boundary equation by using least square, calculating the distance between two straight lines, and finally calculating the width of the wear surface according to the amplification factor of the optical system.
According to the geometrical relation between the width of the wearing surface and the wearing amount, a plurality of methods are provided for calculating the corresponding wearing amount of the contact line.
Specifically, the method comprises the following steps:
R 2 ＝D 2 +(R-h) 2
wherein R is a known contact line radius, D is a measured contact line wearing surface width, and h is a calculated wearing amount. The contact line abrasion h can be obtained by the above formula.
On the basis of obtaining the abrasion amount of the contact wire, the residual height of the contact wire, the width of the contact wire and the abrasion percentage can be calculated by adopting a simple arithmetic method through the known radius of the contact wire.
Compared with the prior art, the contact line abrasion measuring instrument provided by the invention is a non-contact type automatic measuring device, and has the advantages of high automation degree and high measuring precision in the measuring process.
Telecentric lenses used in the instrument have the characteristic of constant imaging magnification. In the process of measuring the contact line, the abrasion amount of the contact line is different, so that the object distance between the abrasion surface and the lens is also different. The magnification of a general lens changes with the change of object distance, and is not suitable for accurately measuring the width of a wearing surface. The invention uses telecentric light path characteristic to ensure that the measuring result of the actual width of the wearing surface is not interfered by the change of the object distance.
In the use process of the instrument provided by the invention, the positioning block of the measuring instrument is tightly attached to the subway line busbar, an industrial camera in the measuring device can clearly shoot an image of the wearing surface of the contact line, and the wearing value of the contact line can be obtained after analyzing and processing the image. In addition to the wear values, the measuring instrument can also obtain three important parameters, namely the contact line residual height, the contact line width and the wear percentage.
The foregoing description is only of the preferred embodiments of the present application and is not intended to limit the same, but rather, various modifications and variations may be made by those skilled in the art. Any modification, equivalent replacement, improvement, etc. made within the spirit and principles of the present application should be included in the protection scope of the present application.
Claims (4)
1. A contact line wear automatic measuring instrument based on machine vision, characterized by comprising:
a housing having a window;
a positioning block is arranged on one side of the surface of the shell, provided with a window, and used for being attached to the surface of the busbar of the fixed contact line, so as to keep the posture of the instrument during measurement;
a light emitting unit is arranged in the shell, light beams emitted by the light emitting unit are projected on the abrasion surface of the contact line to be detected through the window after passing through the reflecting unit, reflected light of the abrasion surface of the contact line to be detected returns to the reflecting unit along the original path, the light beams are received and imaged by a lens group with constant magnification after passing through the reflecting unit, the imaging is shot by an industrial camera,
the specific measuring method of the automatic measuring instrument comprises the following steps: the light beam emitted by the light emitting unit is projected on the abrasion surface of the contact line to be detected, the light beam is received and imaged by the lens group with constant magnification after being reflected by the abrasion surface of the contact line to be detected, the imaging is recorded, and the imaging is obtained by using an image detection algorithm
The width of the contact line wearing surface to be detected in the image, and the corresponding contact line wearing amount is calculated according to the geometric relationship between the wearing surface width and the wearing amount;
the method for obtaining the detected contact line wearing surface width in the imaging image by using the image detection algorithm comprises the following steps:
binarizing the imaging image;
determining a connected domain belonging to the contact line wearing surface according to the binarized image;
fitting a contact line wearing surface boundary equation according to the connected domain, calculating the distance between the boundaries at two sides of the contact line wearing surface according to the boundary equation, and finally calculating the width of the contact line wearing surface by using the magnification factor of a telecentric lens;
fitting a contact line wear surface boundary equation according to the connected domain includes:
processing the profile of the contact line wearing surface communication domain by using a parallelogram approximation method to obtain coordinates of four vertexes of a quadrilateral, calculating linear equations of two side boundaries of the contact line wearing surface according to the four vertexes of the quadrilateral, obtaining a point set positioned in a set distance range around the linear equations, and fitting a contact line wearing surface boundary equation according to the point set;
according to the geometrical relationship between the width of the wearing surface and the wearing amount, the calculation of the corresponding contact line wearing amount comprises the following steps: calculating the abrasion loss of the contact line by using a chord length bow height method according to the radius of the contact line;
specifically, the method comprises the following steps:
R 2 ＝D 2 +(R-h) 2
wherein R is a known contact line radius, D is the measured contact line abrasion surface width, h is the abrasion loss with the requirement, and the contact line abrasion loss h can be obtained through the formula;
and calculating the residual height of the contact wire, the width of the contact wire and the abrasion percentage according to the abrasion amount of the contact wire.
2. The automatic contact line wear measuring instrument based on machine vision according to claim 1, wherein the central axis of the light emitting unit coincides with the optical axis of the lens group of constant magnification within a set range.
3. The machine vision based contact line wear automatic measuring instrument according to claim 1, wherein the light emitting unit employs a hollow surrounding light source.
4. The machine vision based contact line wear automatic measuring instrument of claim 1, further comprising a processor coupled to the industrial camera, wherein the processor employs an embedded processor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710918729.0A CN107560545B (en) | 2017-09-30 | 2017-09-30 | Contact line abrasion automatic measuring instrument and measuring method based on machine vision |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710918729.0A CN107560545B (en) | 2017-09-30 | 2017-09-30 | Contact line abrasion automatic measuring instrument and measuring method based on machine vision |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107560545A CN107560545A (en) | 2018-01-09 |
| CN107560545B true CN107560545B (en) | 2024-03-15 |
Family
ID=60984600
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710918729.0A Active CN107560545B (en) | 2017-09-30 | 2017-09-30 | Contact line abrasion automatic measuring instrument and measuring method based on machine vision |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107560545B (en) |
Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108759670B (en) * | 2018-05-31 | 2020-02-04 | 成都唐源电气股份有限公司 | Contact line abrasion dynamic detection device based on non-contact detection technology |
| CN109186510A (en) * | 2018-08-09 | 2019-01-11 | 东莞市诺丽电子科技有限公司 | A kind of vehicular contact net Abrasion detecting method |
| CN109211120B (en) * | 2018-09-25 | 2019-10-08 | 北京华开领航科技有限责任公司 | Contact line Abrasion detecting device |
| CN110503048B (en) * | 2019-08-26 | 2020-07-17 | 中铁电气化局集团有限公司 | Identification system and method for suspension device of rigid contact net |
| CN111612748A (en) * | 2020-05-11 | 2020-09-01 | 上海华力集成电路制造有限公司 | Tool bit abrasion monitoring method and monitoring system thereof |
| CN112729126A (en) * | 2020-12-30 | 2021-04-30 | 重庆瑞莱尔博自动化设备有限公司 | Contact line abrasion wireless measuring instrument and method based on laser vision |
| CN112816501A (en) * | 2021-01-05 | 2021-05-18 | 中钞印制技术研究院有限公司 | Bill quality detection device, evaluation device and bill quality detection method |
| CN113804123B (en) * | 2021-09-07 | 2023-07-07 | 中国铁道科学研究院集团有限公司 | Method and device for detecting abrasion of rigid suspension contact line |
| CN114909990B (en) * | 2022-03-02 | 2024-04-05 | 上海天链轨道交通检测技术有限公司 | Vehicle-mounted non-contact line abrasion measuring method, device and system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1785730A (en) * | 2005-12-02 | 2006-06-14 | 济南蓝动激光技术有限公司 | Hand-push type multifunction laser contact net detection instrument |
| CN106225727A (en) * | 2016-08-07 | 2016-12-14 | 哈尔滨工业大学 | Array zeroing laser big working distance autocollimation and method |
| CN207365909U (en) * | 2017-09-30 | 2018-05-15 | 济南蓝动激光技术有限公司 | Contact line abrasion automatic measurer based on machine vision |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DK2972479T3 (en) * | 2013-03-13 | 2020-11-30 | Ipg Photonics Canada Inc | METHODS AND SYSTEMS FOR DESCRIPTION OF LASER MACHINING PROPERTIES BY MEASURING KEYHOLE DYNAMICS BY INTERFEROMETRY |
-
2017
- 2017-09-30 CN CN201710918729.0A patent/CN107560545B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1785730A (en) * | 2005-12-02 | 2006-06-14 | 济南蓝动激光技术有限公司 | Hand-push type multifunction laser contact net detection instrument |
| CN106225727A (en) * | 2016-08-07 | 2016-12-14 | 哈尔滨工业大学 | Array zeroing laser big working distance autocollimation and method |
| CN207365909U (en) * | 2017-09-30 | 2018-05-15 | 济南蓝动激光技术有限公司 | Contact line abrasion automatic measurer based on machine vision |
Also Published As
| Publication number | Publication date |
|---|---|
| CN107560545A (en) | 2018-01-09 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN107560545B (en) | Contact line abrasion automatic measuring instrument and measuring method based on machine vision | |
| CN109414992B (en) | Optical system for measuring contact strength between pantograph and overhead line | |
| US10088300B2 (en) | System and method for inspecting the geometric parameters of the wheels of railway vehicles | |
| EP0467984B1 (en) | A plant for track-based detection of the wheel profile of train wheels | |
| CN100494882C (en) | Aerial line wear detection device base on image processing | |
| US8655540B2 (en) | Rail vehicle identification and processing | |
| WO2014136976A1 (en) | Overhead line position measuring device and method | |
| CN108725511B (en) | Real-time position correction method for rail corrugation measuring point | |
| US20200408682A1 (en) | Optical Wheel Evaluation | |
| KR101927648B1 (en) | Vehicle operation fault detection system and method | |
| CN210570537U (en) | Bow net contact wire abrasion on-line detection device | |
| RU2430331C2 (en) | Device to measure contact aerial wear by image processing | |
| US20180031366A1 (en) | Abrasion inspection apparatus, abrasion inspection method, and program | |
| CN207365909U (en) | Contact line abrasion automatic measurer based on machine vision | |
| CN105158273A (en) | Optical cable surface defect detecting system based on planar array CMOS cameras | |
| CN110672035A (en) | Vision measurement method and device | |
| NL2016637A (en) | Rail profile monitoring, e.g. geometry of the frogs. | |
| RU2486466C2 (en) | Method for automatic measurement of contact wire wear (wires of catenary system) | |
| KR102004909B1 (en) | Tongue rail inspection system for detecting the close contact | |
| EP1756513A4 (en) | A method and a system for height triangulation measurement | |
| CN105292179A (en) | Rim size detection method | |
| CN114152214A (en) | Method, device and system for detecting loss of steel rail profile | |
| JP2014169940A (en) | Overhead wire position measuring apparatus and method | |
| JP6855405B2 (en) | Tram wire measuring method and trolley wire measuring device | |
| CN218674759U (en) | Intelligent device suitable for track abrasion detection |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |