CN111536881A - Crack automatic detector with camera - Google Patents
Crack automatic detector with camera Download PDFInfo
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- CN111536881A CN111536881A CN202010385894.6A CN202010385894A CN111536881A CN 111536881 A CN111536881 A CN 111536881A CN 202010385894 A CN202010385894 A CN 202010385894A CN 111536881 A CN111536881 A CN 111536881A
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01B—MEASURING LENGTH, THICKNESS OR SIMILAR LINEAR DIMENSIONS; MEASURING ANGLES; MEASURING AREAS; MEASURING IRREGULARITIES OF SURFACES OR CONTOURS
- G01B11/00—Measuring arrangements characterised by the use of optical techniques
- G01B11/02—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness
- G01B11/022—Measuring arrangements characterised by the use of optical techniques for measuring length, width or thickness by means of tv-camera scanning
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8851—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/50—Constructional details
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04N—PICTORIAL COMMUNICATION, e.g. TELEVISION
- H04N23/00—Cameras or camera modules comprising electronic image sensors; Control thereof
- H04N23/60—Control of cameras or camera modules
- H04N23/695—Control of camera direction for changing a field of view, e.g. pan, tilt or based on tracking of objects
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04Q—SELECTING
- H04Q9/00—Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/84—Systems specially adapted for particular applications
- G01N21/88—Investigating the presence of flaws or contamination
- G01N21/8851—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges
- G01N2021/8887—Scan or image signal processing specially adapted therefor, e.g. for scan signal adjustment, for detecting different kinds of defects, for compensating for structures, markings, edges based on image processing techniques
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Abstract
The invention relates to the technical field of engineering safety monitoring instrument inspection devices, and aims to provide an automatic crack detector with a camera, which comprises a support, wherein the camera is arranged on the support, a first driving mechanism for driving the camera to rotate around the vertical direction and a second driving mechanism for enabling the camera to move along the horizontal direction are arranged on the support, the automatic crack detector also comprises vertical scale targets which are respectively stuck to the wall surface along the length direction and the width direction of a crack, the first driving mechanism and the second driving mechanism are started, the camera is enabled to be over against the crack on the wall for crack picture acquisition, and the crack picture shot by the camera is provided with two vertical scale targets. The problem of can not realize once determining width value and length value of crack, the data of gathering are not comprehensive enough is solved. The method has the effects of realizing the measurement of the width value and the length value of the crack at one time, automatically carrying out periodic crack data measurement, along with convenient operation, more comprehensive measured crack data and more accurate deformation analysis result.
Description
Technical Field
The invention relates to the technical field of engineering safety monitoring instrument inspection devices, in particular to an automatic crack detector with a camera.
Background
With the development and progress of society and the acceleration of urbanization process, more and more cities carry out large and medium-sized engineering construction. How to effectively control the deformation of a major engineering structure or perform deformation monitoring in the surrounding urban environment of mass people flow is a hotspot and difficulty which arouses wide social attention. In a plurality of influence factors of major engineering structure deformation and surrounding urban environment monitoring deformation hazards, the length, width and depth of the crack are taken as reference indexes, but for convenience of measurement, the influence of the length and depth parameters on the crack measurement precision is generally ignored, and the width of the crack is taken as a main index. Especially in the deformation of the tunnel structure, the dam, the slope and the wall body of the operation subway, the crack width is used as the judgment and early warning index.
The crack monitoring technology includes contact monitoring and non-contact monitoring. The contact monitoring instrument mainly comprises an electromagnetic extensometer, a surface extensometer and an optical fiber joint meter, and is mainly realized by a method of planting piles and pulling steel wires or optical fibers on two sides of the width of a crack. The electromagnetic extensometer and the surface extensometer have the defects of poor durability and interference resistance, and the optical fiber joint meter is not sensitive to electromagnetic interference and radio frequency interference and has high precision. However, the contact type crack gauges are generally prone to damage, one crack gauge can only measure the width value of one crack during each operation, the length values of the cracks cannot be acquired simultaneously, and efficiency is low.
The non-contact monitoring instruments mainly comprise a GPS (global positioning system), a total station and the like, have the defects of high cost, complex installation, complex calculation and insufficient real-time performance, and are not beneficial to monitoring and early warning and large-scale popularization and application.
And a non-contact automatic crack monitoring technology based on a laser ranging principle can realize real-time monitoring and high measurement precision, but has the defects of high cost, being in a research stage at present and being not beneficial to popularization.
The conventional crack meter and the manual monitoring method have low efficiency, and the monitoring result is not submitted in time, so that the conventional crack meter and the manual monitoring method are not suitable for modern safety monitoring management any more.
The above prior art solutions have the following drawbacks: the conventional crack meter cannot measure the width value and the length value of a crack at one time, the efficiency is low, the collected data are not comprehensive enough, the accuracy of a deformation analysis result is reduced, major engineering crack monitoring and early warning and large-specification popularization and application are not facilitated, and an improvement space exists.
Disclosure of Invention
The invention aims to provide an automatic crack detector with a camera, which can realize the measurement of the width value and the length value of a crack at one time, improves the measurement efficiency, simultaneously has more comprehensive measured crack data, is favorable for improving the accuracy of a deformation analysis result, and is favorable for major engineering crack monitoring and early warning and large-specification popularization and application.
The above object of the present invention is achieved by the following technical solutions:
the utility model provides a crack automatic checkout appearance from taking camera, includes the support, the camera is installed on the support, be provided with on the support and be used for the drive the camera is around vertical direction pivoted first actuating mechanism and is used for making the second actuating mechanism of camera along the horizontal direction upward movement still includes the perpendicular scale mark target of pasting along cracked length direction and width direction on the wall, starts first actuating mechanism with second actuating mechanism makes the camera just carries out crack photo collection to the crack on the wall, the crack photo that the camera was shot all has perpendicular scale mark target.
By adopting the technical scheme, the first driving mechanism on the bracket drives the camera to rotate around the vertical direction so as to adjust the vertical angle of the camera facing to the crack on the wall; a second driving mechanism on the bracket drives the camera to move in the horizontal direction so as to adjust the horizontal angle of the camera from a crack on the wall; the first driving mechanism and the second driving mechanism are started, when the camera is driven to rotate to a position which is basically vertical to the wall surface and is opposite to the crack on the wall, the camera is controlled to acquire an image of the crack with the vertical scale target, and the length value and the width value of the crack are respectively read according to the vertical scale target; and then the crack automatic detector of taking the camera certainly can realize the purpose of once survey width value and the length value of crack, and measurement of efficiency improves, and simultaneously, measured crack data is more comprehensive more, is favorable to improving the accuracy of deformation analysis result, is favorable to major engineering crack monitoring early warning and big standard popularization and application.
The present invention in a preferred example may be further configured to: the intelligent crack detection device comprises a support, a main board, a camera and a data acquisition module, wherein the main board is installed on the support, a CPU runs on the main board, the camera is electrically connected with the CPU, a power source of a first driving mechanism and a power source of a second driving mechanism are electrically connected with the CPU, the main board is provided with the data acquisition module, the data acquisition module is used for learning measurement, automatically searching cracks and automatically acquiring crack pictures, the learning measurement result of the data acquisition module is input into the CPU through the main board in an electric signal mode, and the CPU sends a control signal to the power source of the first driving mechanism or the power source of the second driving mechanism according to the received electric signal to drive the camera to automatically search cracks and automatically acquire crack pictures.
By adopting the technical scheme, the data acquisition module arranged in the mainboard is used for learning measurement, automatically searching cracks and automatically acquiring cracks and photos, the data acquisition module sends an electric signal to the CPU through the mainboard, the CPU sends a control signal to the power source of the first driving mechanism and the power source of the second driving mechanism according to the received electric signal to control the power source of the first driving mechanism and the power source of the second driving mechanism to start, and then the automatic crack detector with the camera can automatically perform periodic crack data measurement without manual measurement, and is convenient to operate; meanwhile, the measured crack data are more comprehensive and more, the accuracy of the deformation analysis result is improved, and the crack monitoring and early warning method is favorable for major engineering crack monitoring and early warning and large-specification popularization and application.
The present invention in a preferred example may be further configured to: after the camera collects the first-stage picture of the crack, the data collection module automatically reads the horizontal angle and the vertical angle of the observed crack in the first-stage picture, and records and stores the horizontal angle and the vertical angle as a learning value; when a second-stage picture and a later picture of the observed crack need to be acquired, the data acquisition module transmits the stored learning value to the CPU in an electric signal mode, the CPU outputs control signals to the power source of the first driving mechanism and the power source of the second driving mechanism, the camera is driven to automatically rotate to an angle corresponding to the learning value, and the observed crack is automatically photographed for the second stage and the later.
Through adopting above-mentioned technical scheme, the data acquisition module is based on the study measurement, the horizontal angle and the vertical angle of being observed the crack in the first-phase photo are read automatically, and the record storage is as the study value, provide the basis for the camera carries out the automatic crack position of looking for next time, make CPU can be according to the result of study measurement, control first actuating mechanism and second actuating mechanism, the drive camera autogiration is to the angle that the study value corresponds, the collection of automatic crack photo carries out, high durability and convenient operation, the function in study measurement, automatic crack and automatic acquisition crack photo are sought to the realization.
The present invention in a preferred example may be further configured to: the main board is provided with a data processing module, and the data processing module adopts an affine transformation geometric correction mode to automatically correct distortion of the crack photo.
By adopting the technical scheme, the geometric correction mode of affine transformation is adopted to carry out distortion correction on the crack pictures, the uniformity of the collected pictures is ensured, the influence of influence factors such as shaking, inconsistent size proportion of the shot cracks and the like on the deformation analysis result of the images collected by the camera is reduced, and the accuracy of the deformation analysis result is improved.
The present invention in a preferred example may be further configured to: after the automatic distortion correction is carried out on the crack photo, the data processing module reads the crack width value and the crack length value on the stored photo, and the crack deformation and the accumulated deformation are calculated and stored.
By adopting the technical scheme, the data processing module arranged in the mainboard has the function of automatically acquiring and processing crack data, is convenient to operate, provides data basis for analysis of deformation results, and is favorable for timely structural deformation analysis and measures.
The present invention in a preferred example may be further configured to: the CPU is electrically connected with a display screen, and the data processing module automatically generates a crack deformation and accumulated deformation curve graph according to the stored crack deformation and accumulated deformation and displays the curve graph on the display screen.
By adopting the technical scheme, the data processing module has the function of automatically generating the crack deformation and accumulated deformation curve chart, and displays the curve chart on the display screen so as to visually acquire the deformation data information of the crack, thereby being beneficial to timely finding the deformation condition of the crack and taking measures in time.
The present invention in a preferred example may be further configured to: the CPU is also electrically connected with an alarm module, when the deformation of the crack and the accumulated deformation exceed the early warning value, the data processing module sends a control signal to the alarm module through the CPU, and the alarm module gives an alarm.
By adopting the technical scheme, the early warning value is set according to the crack deformation standard, and when the crack deformation and the accumulated deformation exceed the early warning value, the data processing module sends a control signal to the alarm module through the CPU, so that the alarm module gives an alarm to remind field workers to check the crack deformation in time and take measures.
The present invention in a preferred example may be further configured to: the CPU is also electrically connected with a data transmission module for remote data transmission.
By adopting the technical scheme, the data transmission module remotely transmits the data information acquired by the camera to the terminal, so that the remote communication function is realized, the terminal is favorable for assisting the automatic crack detector with the camera to carry out measurement, the automatic crack detector with the camera is convenient to uniformly manage, and the major engineering crack monitoring and early warning and the large-scale popularization and application are further favorable.
The present invention in a preferred example may be further configured to: the support includes bottom plate, installation frame and articulated slab, a actuating mechanism includes first pivot and first motor, the vertical setting of first pivot and rotation are connected on the bottom plate, the installation frame with first pivot fixed connection, first motor is fixed on the installation frame and with the tip fixed connection of first pivot, the articulated slab articulate in on the installation frame, the mainboard is installed on the articulated slab.
Through adopting above-mentioned technical scheme, start first motor, the output shaft of first motor rotates, drives first pivot and rotates for first pivot drives the installation frame and rotates, and then rotates around first pivot with the mainboard on the articulated slab of installation frame articulated setting, indirectly realizes the camera around vertical direction pivoted purpose, with the angle of adjustment camera towards crack on the wall.
The present invention in a preferred example may be further configured to: the second driving mechanism comprises a second rotating shaft and a second motor, the hinged plate is hinged to the installation frame through the second rotating shaft arranged horizontally, and the second motor is fixed to the installation frame and fixedly connected with the end portion of the second rotating shaft.
Through adopting above-mentioned technical scheme, start the second motor, the output shaft of second motor rotates, drives the second pivot and rotates for mainboard on the articulated slab rotates around the second pivot, and then indirectly realizes the purpose that the drive camera moved along wall body place direction, with the cracked distance on the adjustment camera distance wall.
In summary, the invention includes at least one of the following beneficial technical effects:
1. the crack automatic detector with the camera can achieve the purpose of measuring the width value and the length value of the crack at one time, the measuring efficiency is improved, meanwhile, the measured crack data are more comprehensive and more, the accuracy of a deformation analysis result is improved, and the crack automatic detector is beneficial to major engineering crack monitoring and early warning and large-specification popularization and application;
2. the CPU and the data acquisition module are used for automatically measuring the periodic crack data, manual measurement is not needed, and the operation is convenient; meanwhile, the measured crack data are more comprehensive, the accuracy of a deformation analysis result is improved, and major engineering crack monitoring and early warning and large-specification popularization and application are facilitated;
3. distortion correction is carried out on the crack photos by adopting a geometric correction mode of affine transformation, so that the uniformity of the acquired photos is ensured, and the accuracy of a deformation analysis result is improved;
4. the data processing module arranged in the camera has the function of automatically acquiring and processing crack data, is convenient to operate and provides a data basis for deformation result analysis;
5. the data processing module has the function of automatically generating a crack deformation and accumulated deformation curve chart, and displays the curve chart on a display screen so as to intuitively acquire the deformation data information of the crack, thereby being beneficial to finding out the deformation condition of the crack in time and taking measures in time;
6. when the crack deformation and the accumulated deformation exceed the early warning value, the alarm module gives an alarm to remind field workers to check the crack deformation in time and take measures;
7. the data transmission module remotely transmits data information acquired by the camera to the terminal, so that a remote communication function is realized, the terminal is favorable for assisting the automatic crack detector with the camera to perform measurement, and the automatic crack detector with the camera is convenient to perform unified management.
Drawings
FIG. 1 is a schematic diagram of an overall structure of an automatic crack detector with a camera;
FIG. 2 is a top view of an automatic crack detector with a camera;
FIG. 3 is a schematic view of the position of a crack in a wall relative to a vertical scale target;
fig. 4 is a schematic communication diagram of the data acquisition module, the data processing module, the data transmission module and the terminal.
In the figure, 1, a bracket; 101. a base plate; 102. a mounting frame; 103. a hinge plate; 2. a first rotating shaft; 3. a first motor; 4. a hinged lever; 5. mounting a plate; 6. a second rotating shaft; 7. a second motor; 8. a main board; 801. an LCD screen interface; 802. a camera interface; 803. a card slot; 804. a power supply USB port; 805. a motor power line interface; 806. a PWM signal line interface; 9. a first scale target; 10. a second scale target; 11. a camera; 12. a display screen; 13. cracking; 14. a wall body; 15. a level gauge.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings.
The present embodiment is only for explaining the present invention, and it is not limited to the present invention, and those skilled in the art can make modifications of the present embodiment without inventive contribution as needed after reading the present specification, but all of them are protected by patent law within the scope of the claims of the present invention.
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, 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 some, but not all, embodiments of the present invention. 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.
In addition, the term "and/or" herein is only one kind of association relationship describing an associated object, and means that there may be three kinds of relationships, for example, a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" herein generally indicates that the former and latter related objects are in an "or" relationship, unless otherwise specified.
The embodiments of the present invention will be described in further detail with reference to the drawings attached hereto.
Referring to fig. 1 and 2, an embodiment of the invention provides an automatic crack detector with a camera, which includes a bottom plate 101, a mounting frame 102 and a hinge plate 103, wherein the bottom plate 101, the mounting frame 102 and the hinge plate 103 form a support 1, and the support 1 is a plastic transparent support 1 and is used for placing various hardware parts of an automatic crack detector 13 of a wireless remote self-contained camera 11 with a camera 11.
Threaded holes are formed in the four corner positions of the bottom plate 101, and screws are connected in the threaded holes in a threaded mode so as to be used for fixing the position of the automatic crack 13 detector with the camera 11.
The upper surface of bottom plate 101 is put at the central point and is rotated the first pivot 2 that is connected with vertical setting, installation frame 102 is "concave" style of calligraphy, the bottom of installation frame 102 is fixed on first pivot 2, installation frame 102 and 2 fixed connection of first pivot, fixed mounting has first motor 3 on the installation frame 102, the output shaft of first motor 3 and the tip fixed connection of first pivot 2, first pivot 2 is close to the one end seal of first motor 3 and is carved with the dentate line, the dentate line threaded connection of the output shaft of first motor 3 and first pivot 2.
The first rotating shaft 2 and the first motor 3 constitute a first driving mechanism for driving the camera 11 to rotate around the vertical direction.
The hinged plate 103 comprises two hinged rods 4 and a mounting plate 5 fixedly connected between the upper ends of the two hinged rods 4, two upper ends of the mounting frame 102 and the lower ends of the two hinged rods 4 are respectively connected with a second rotating shaft 6 in a rotating mode, a second motor 7 is fixedly mounted on the inner side wall of the mounting frame 102, an output shaft of the second motor 7 is fixedly connected with one of the second rotating shafts 6, one end, close to the second motor 7, of the second rotating shaft 6 is printed with toothed grains, and the output shaft of the second motor 7 is in threaded connection with the toothed grains of the second rotating shaft 6.
The second rotating shaft 6 and the second motor 7 constitute a second driving mechanism for moving the camera 11 along the direction of the wall 14.
The mounting board 5 is fixedly provided with a main board 8, and the main board 8 is integrated with a CPU, an LCD screen interface 801, a camera 11 interface 802, a card slot 803, a power supply USB port 804, a motor power line interface 805, and a PWM signal line interface 806.
The model of the CPU is a RISC-V64 dual-core processor, the standard frequency of the CPU is 400Mhz, and the CPU runs on the mainboard 8. The LCD screen interface 801 is electrically connected to a display screen 12, and the display screen 12 is used for displaying a critical crack 13 picture, a crack 13 deformation amount, an accumulated deformation amount value and a corresponding curve graph in time.
The camera 11 is electrically connected with the camera 11 interface 802, and the camera 11 is used for collecting images of the crack 13.
The PWM signal line interface 806 is electrically connected to an antenna, which adopts a 2.4802.11. b/g/n wireless transmission function standard for wirelessly transmitting the acquired crack 13 deformation and crack 13 picture data. A TF card is installed in the card slot 803, and the TF card stores the numerical values of the deformation amount and the accumulated deformation amount of the crack 13 and the data of the crack 13 picture, and realizes a function of downloading the numerical values of the deformation amount and the accumulated deformation amount of the crack 13 and the data of the crack 13 picture.
The antenna and the TF card form a data transmission module for remote data transmission, the antenna has the functions of wirelessly transmitting data information of deformation and accumulated deformation and key crack 13 photos to the terminal, and the TF card has the function of downloading and transmitting all stored photos and information to the terminal.
The power supply USB port 804 is used to connect the USB data line to a power supply terminal to provide a working power supply for the motherboard 8.
The motor power line interface 805 is used for electrically connecting the first motor 3 and the second motor 7 with the CPU, and outputting a control electrical signal to the motors through the I/O port of the CPU to control the first motor 3 and the second motor 7 to operate.
The upper surface of the bottom plate 101 is fixedly provided with a level gauge 15 along the direction of two adjacent side lengths so as to assist the bottom plate 101 to keep a horizontal state after being installed, and further indirectly enable the camera 11 installed on the main plate 8 to keep a horizontal state when the hinged plate 103 is opposite to the wall so as to be opposite to the wall crack 13.
Referring to fig. 3, still including pasting first scale mark target 9 and the second scale mark target 10 of fixing at the length direction and the width direction of crack 13 respectively, first scale mark target 9 and second scale mark target 10 body coupling, first scale mark target 9 and second scale mark target 10 constitute perpendicular scale mark target, in this embodiment, select the perpendicular scale mark target of the take scale film of self-staining nature or the PVC material of taking the scale, through the powerful non-setting adhesive of the strenghthened type on the back strongly paste the crack 13 length direction or the width direction of fixing on the wall during the use, firmly paste with wall body 14, form integratively, have the characteristics that are difficult for droing, and convenient to use, high work efficiency, waterproof sunscreen prevents scraping and is with low costs.
Each crack 13 corresponds to a pair of vertical scale targets, the vertical scale targets are used for assisting in correcting malformation changes of the crack 13 photos, and the vertically arranged first scale target 9 and the second scale target 10 are used for calibrating deformation of the crack 13 photos caused by slight changes of shooting angles and distances of the camera 11, so that the angle and the distance of the photos of the crack 13 collected at each stage are consistent, the size error of the measured crack 13 photos is favorably reduced, and the accuracy of monitoring the crack 13 deformation is improved.
Referring to fig. 4, a software module is built in the main board 8, and the software module is used for realizing the functions of automatic image correction, crack 13 deformation calculation and deformation analysis. The software module comprises a data acquisition module and a data processing module.
The data acquisition module has the functions of learning measurement, automatically searching for a target and automatically acquiring a target photo.
Specifically, after the camera 11 is oriented to a horizontal angle in a certain direction, the shooting angle of the camera 11 is basically right opposite to the wall surface, the crack automatic detector with the camera is used for carrying out first-time observation artificial learning, the camera 11 is aligned to an observed crack 13 on the wall, the camera 11 collects a first-phase picture of the crack 13, and automatically reads a right-angle intersection point of a vertical scale target beside the observed crack 13 in the first-phase picture, namely a horizontal angle and a vertical angle of a right-angle zero point, and records and stores the right-angle intersection point as a learning value; when the second-stage picture and the later pictures of the observed crack 13 need to be acquired, the CPU outputs a control electric signal to the motor through the I/O port according to the stored learning value, and controls the output shaft of the motor to automatically rotate by an angle corresponding to the learning value, so that the camera 11 is right opposite to the observed crack 13, and the second-stage picture and the later pictures of the observed crack 13 are automatically taken.
When at least two cracks 13 exist on the same wall, or the shooting angle of the camera 11 to the cracks 13 is basically vertical to the wall surface, the crack automatic detector with the camera sequentially observes the length and width changes of all the cracks 13.
Specifically, when the crack automatic detector with the camera is used for carrying out first-time observation artificial learning, the camera 11 is sequentially aligned to the observed cracks 13 on the wall, the camera 11 sequentially collects first-phase pictures of the cracks 13, sequentially and automatically reads horizontal angles and vertical angles of the observed cracks 13 in the first-phase pictures, and sequentially records and stores the horizontal angles and the vertical angles as learning values; according to different stored learning values, the camera 11 automatically finds the crack 13 at the corresponding position to collect the second-stage picture and the later pictures.
The data processing module has the functions of automatically correcting the distortion of the crack photo, collecting the length and the width of the crack, calculating the crack deformation and the accumulated deformation, automatically generating a crack deformation and accumulated deformation curve graph, and analyzing the crack deformation precision and the deformation result.
Because the image collected by the camera 11 may have factors affecting the deformation analysis result, such as jitter and inconsistency of the size ratio of the shooting crack 13, the collected image is subjected to automatic distortion correction of the crack picture.
In this embodiment, the automatic distortion correction of the crack picture is realized by adopting a geometric correction mode of affine transformation, and the generated distorted picture is corrected by utilizing the affine transformation. It typically includes a scaling offset, a rotation. The image correction formula is as follows, and formula (1) and formula (2) are algebraic expressions and matrix expressions using affine transformation:
wherein x and y are coordinates before conversion,
in order to be able to convert the coordinates,
are affine transformation parameters.
Determining the coordinates of at least 3 control points required to be acquired by affine transformation parameters, in this embodiment, 4 to 6 control points are acquired at clear positions of vertical and horizontal scale targets on an acquired image, and then solved by using the principle of least square method
Affine transformation parameters, and then obtaining
And correcting the generated distorted image for the converted coordinates, so that the image correction achieves the best effect.
And then, collecting the length and the width of the crack of the corrected picture, and reading the length value and the width value of the crack according to the vertical scale target. Readings are taken when the scale of the vertical scale target ensures integrity. If the vertical scale target at the crack change position cracks, the length value and the width value of the crack are not recommended to be read on the vertical scale target, at the moment, the length and the width of the actual crack value can be obtained by dividing the size measured on the photo by the photo scale, and the scale is the ratio of the size measured on the scale photo to the actual scale value.
The calculation of the crack deformation amount and the accumulated deformation amount comprises the calculation of the change of the crack length L and the accumulated deformation amount and the calculation of the change of the crack width W and the accumulated deformation amount.
The specific steps of calculating the change of the crack length L are as follows:
reading two end point values of the crack on the first scale target 9
And
length of taking
Memory for recordingIs the first stage
，
The second stage is
The variable quantity is
=
The accumulated variation is
；
The third stage is
The variable quantity is
The accumulated variation is
；
The nth stage is
The amount of change is, cumulatively
The variable quantity is
。
The specific steps of calculating the change of the crack width W are as follows:
the width of the crack is read on the second scale target 10, typically at the two ends of the maximum interval
And
taking the maximum width
Is recorded as the first stage
，
The second stage is
The variable quantity is
=
Accumulated variation amount
；
The third stage is
The variable quantity is
The accumulated variation is
；
The nth stage is
The variable quantity is
The accumulated variation is
。
In this embodiment, in order to improve the accuracy of the monitoring result, a plurality of width values W including the maximum width value are read on the second scale target 10 according to the actual length of the crack
And the variation and the accumulated variation of the batch width value are monitored, so that the abnormal change of the crack 13 can be found in time.
Based on the result of the deformation calculation, the generated crack length deformation graph and crack width deformation graph are displayed on the display screen 12.
Still electrically connected has alarm module (not shown in the figure) on the mainboard 8, when the accumulative change of crack length L and the accumulative change of crack width W exceeded the early warning value, alarm module reported to the police to and remind on-the-spot staff to look over the actual conditions of crack 13 in time. The early warning value is set according to the deformation standard of the crack 13. In this embodiment, the alarm module is an LED indicator light, and the LED indicator light flashes to give an alarm.
In this embodiment, the deformation rate of the crack 13, that is, the ratio of the accumulated variation to the time, may also be used as a parameter value for measuring the deformation of the crack 13.
When the accumulated variation of the crack length L and the accumulated variation of the crack width W exceed the early warning value, corresponding crack deformation and accumulated deformation data information, corresponding first-stage photos or corresponding continuous photos are transmitted to a monitoring platform through a CPU, automatic achievement analysis is carried out on the monitoring platform, timely transmission and timely alarming are facilitated, the phenomenon that resources of the monitoring platform are occupied by transmitting a large number of photos is avoided, the processing speed of the monitoring platform is slowed, and the flow is consumed is avoided; the remaining photos may be transferred to the monitoring platform by post-download or post-lag. The monitoring platform is terminal equipment.
Referring to fig. 4, the monitoring platform performs file management by receiving data information of the antenna and the TF card through internet wireless communication. The crack automatic detector with the camera is managed in a unified mode by means of the monitoring platform, the crack automatic detector with the camera is subjected to initial setting such as coordinate system correction and measuring point, the camera 11 is arranged on the monitoring platform to conduct remote control such as periodic shooting, directional crack target point searching and the like, so that the camera is controlled to conduct learning measurement and automatic monitoring, and management work is facilitated. And the monitoring platform is based on the application server, and carries out calculation and analysis on a deformation result, such as difference processing and the like, according to the received data information, and outputs the result after obtaining the analysis result so as to assist the crack automatic detector with the camera to carry out measurement.
The monitoring platform can also directly superpose the corrected images, so that the vertical scale targets of each corrected image are superposed to generate a crack change diagram, and the change condition of the crack 13 can be observed visually. When the width or the length of the observed crack 13 changes, the image of the crack 13 shot and collected by the camera 11 changes after being superposed to form a dynamic graph; when the width and the length of the observed crack 13 are not changed, the camera 11 captures the same acquired crack 13 image as the acquired first-phase image after superposition.
The implementation principle of the embodiment is as follows: and fixedly mounting the automatic crack detector with the camera on a wall tripod, a wall or a platform opposite to the crack 13 through a screw.
The crack automatic detector with the camera automatically acquires the horizontal angle and the vertical angle of the observed crack 13 in the first-phase picture of the observed crack 13 by using the camera 11 and the data acquisition module which is arranged on the main board 8 in a built-in mode, records and stores the horizontal angle and the vertical angle as the learning value, and transmits the learning value to the CPU in an electric signal mode by using the data acquisition module to realize the purpose of learning and measuring.
When the second and later photo collection is carried out, according to the learning value, the CPU sends control signals to the first motor 3 and the second motor 7 through the I/O port, so that the first motor 3 and the second motor 7 drive the first rotating shaft 2 and the second rotating shaft 6 to rotate, the camera 11 is driven to rotate to the angle position corresponding to the learning value, the second and later photo collection is carried out on the crack 13 to be observed, and the aims of automatically searching the crack 13 and automatically collecting the crack 13 photo by the camera 11 are fulfilled.
After the acquired photo is subjected to automatic distortion correction of the crack photo through the data processing module, the width value and the length value of the crack 13 are read on the vertical scale target, the deformation and the accumulated deformation of the crack 13 can be calculated by utilizing the width value and the length value of the crack 13 acquired by the photo at each stage, and a curve graph of the deformation and the accumulated deformation of the crack 13 is automatically generated and displayed on the display screen 12.
Meanwhile, the data processing module analyzes the deformation result of the crack 13, when the deformation and the accumulated deformation of the crack 13 exceed the early warning value, the data processing module inputs a trigger signal to the CPU, and the CPU outputs a control signal to the alarm module to control the alarm module to give an alarm.
At this time, the deformation amount and the accumulated deformation amount data of the abnormal crack 13, the change curve graph and the key crack picture are transmitted to the monitoring platform in real time through the antenna for further analysis, so that the consumption of transmission flow and the occupation of bandwidth resources are reduced, and the normal work of the monitoring platform is ensured. And at the later stage, the collected related photos and all data information about the crack 13 are uploaded to a monitoring platform through a TF card or are transmitted to the monitoring platform in a delayed mode for data storage and analysis.
And then the crack automatic detector of taking the camera can realize width value and the length value of once survey crack, and measurement efficiency improves, simultaneously, carry out periodic crack data measurement automatically, and with data remote transmission to backstage of gathering, the crack automatic detector of taking the camera can be fast, effectively, realize long-range survey crack width, length variation with low costs, need not manual measurement, and convenient operation, measured crack data is more comprehensive, be favorable to improving the accuracy of deformation analysis result, be favorable to major engineering crack monitoring early warning and big standard popularization and application.
Claims (10)
1. The utility model provides a crack automatic checkout appearance from taking camera, includes support (1), install camera (11) on support (1), its characterized in that, be provided with on support (1) and be used for the drive camera (11) are around vertical direction pivoted first actuating mechanism and are used for making camera (11) are along the second actuating mechanism of horizontal direction upward movement, still include the perpendicular scale mark target of pasting along the length direction and the width direction of crack (13) respectively on the wall, start first actuating mechanism with second actuating mechanism makes camera (11) just carry out crack (13) photo collection to crack (13) on the wall, crack (13) photo that camera (11) was shot all has two perpendicular mark scale.
2. The automatic crack detector with a camera according to claim 1, a main board (8) is arranged on the bracket (1), a CPU runs on the main board (8), the camera (11) is electrically connected with the CPU, the power source of the first driving mechanism and the power source of the second driving mechanism are electrically connected with the CPU, the main board (8) is provided with a data acquisition module which is used for learning measurement, automatically searching for cracks (13) and automatically acquiring photos of the cracks (13), the learning measurement result of the data acquisition module is input into the CPU through the mainboard (8) in the form of electric signals, and the CPU sends a control signal to the power source of the first driving mechanism or the power source of the second driving mechanism according to the received electric signal to drive the camera (11) to automatically search for the crack (13) and automatically collect the picture of the crack (13).
3. The crack automatic detector with the camera is characterized in that after the camera (11) collects a first-stage picture of the crack (13), the data collection module automatically reads the horizontal angle and the vertical angle of the observed crack (13) in the first-stage picture and records and stores the horizontal angle and the vertical angle as a learning value; when a second-stage picture and a later picture of the observed crack (13) need to be acquired, the data acquisition module transmits the stored learning value to the CPU in an electric signal mode, the CPU outputs a control signal to a power source of the first driving mechanism and a power source of the second driving mechanism, the camera (11) is driven to automatically rotate to an angle corresponding to the learning value, and the second-stage and later pictures of the observed crack (13) are automatically taken.
4. The automatic crack detector with the camera as claimed in claim 2, wherein the main board (8) is provided with a data processing module, and the data processing module adopts an affine transformation geometric correction mode to automatically correct distortion of a crack (13) picture.
5. The crack automatic detector with the camera of claim 4, characterized in that after the automatic distortion correction of the crack (13) picture, the data processing module reads the width value and the length value of the crack (13) on the stored picture, calculates and stores the deformation amount and the accumulated deformation amount of the crack (13).
6. The crack automatic detector with the camera of claim 5, wherein the CPU is electrically connected with a display screen (12), and the data processing module automatically generates a crack (13) deformation amount and accumulated deformation amount curve graph according to the stored crack (13) deformation amount and accumulated deformation amount and displays the curve graph on the display screen (12).
7. The crack automatic detector with the camera as claimed in claim 5, wherein the CPU is further electrically connected with an alarm module, when the deformation and the accumulated deformation of the crack (13) exceed the pre-warning value, the data processing module sends a control signal to the alarm module through the CPU, and the alarm module gives an alarm.
8. The automatic crack detector with the camera of claim 2, wherein the CPU is further electrically connected with a data transmission module for remote data transmission.
9. The automatic crack detector with the camera of claim 2, wherein the bracket (1) comprises a bottom plate (101), a mounting frame (102) and a hinge plate (103), the first driving mechanism comprises a first rotating shaft (2) and a first motor (3), the first rotating shaft (2) is vertically arranged and is rotatably connected to the bottom plate (101), the mounting frame (102) is fixedly connected with the first rotating shaft (2), the first motor (3) is fixed on the mounting frame (102) and is fixedly connected with the end part of the first rotating shaft (2), the hinge plate (103) is hinged to the mounting frame (102), and the main plate (8) is mounted on the hinge plate (103).
10. The automatic crack detector with the camera of claim 9, wherein the second driving mechanism comprises a second rotating shaft (6) and a second motor (7), the hinge plates (103) are hinged to the mounting frame (102) through the second rotating shaft (6) horizontally arranged, and the second motor (7) is fixed on the mounting frame (102) and is fixedly connected with the end of the second rotating shaft (6).
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112033972A (en) * | 2020-09-14 | 2020-12-04 | 长安大学 | Road crack detection device |
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