CN115046488B - Space measurement method for grid construction nodes - Google Patents
Space measurement method for grid construction nodes Download PDFInfo
- Publication number
- CN115046488B CN115046488B CN202210681992.3A CN202210681992A CN115046488B CN 115046488 B CN115046488 B CN 115046488B CN 202210681992 A CN202210681992 A CN 202210681992A CN 115046488 B CN115046488 B CN 115046488B
- Authority
- CN
- China
- Prior art keywords
- laser
- range finder
- laser range
- bolt ball
- distance
- 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
- 238000010276 construction Methods 0.000 title claims abstract description 15
- 238000000691 measurement method Methods 0.000 title description 5
- 238000000034 method Methods 0.000 claims abstract description 20
- 238000001514 detection method Methods 0.000 claims description 23
- 229910000831 Steel Inorganic materials 0.000 claims description 7
- 239000010959 steel Substances 0.000 claims description 7
- 238000005259 measurement Methods 0.000 description 6
- 238000004364 calculation method Methods 0.000 description 5
- 238000012544 monitoring process Methods 0.000 description 4
- 230000002159 abnormal effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000009435 building construction Methods 0.000 description 1
- 238000013135 deep learning Methods 0.000 description 1
- 230000001419 dependent effect Effects 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 238000013507 mapping Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
Classifications
-
- 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
- G01B11/14—Measuring arrangements characterised by the use of optical techniques for measuring distance or clearance between spaced objects or spaced apertures
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Length Measuring Devices By Optical Means (AREA)
Abstract
The invention discloses a method for measuring the distance between grid construction nodes, which comprises the following steps of; step 1): resetting the equipment; step 2): collecting an image of a net rack building, and detecting adjacent bolt balls in the image; step 3): adjusting the posture of the laser range finder to enable the laser spots of the laser range finder to coincide with the circle center of the bolt ball; step 4): obtaining the distance from the laser range finder to the bolt ball, and calculating the horizontal angle and the vertical angle of the attitude sensor to obtain a vector; step 5): adjusting the posture of the laser range finder to enable the laser spot of the laser range finder to coincide with the center of the nearest bolt ball at the left lower part of the bolt ball; step 6): obtaining the distance from the laser range finder to the bolt ball, and calculating the horizontal angle and the vertical angle of the attitude sensor to obtain a vector; step 7): the distance between the two bolt balls is obtained through the distance and the vector in the step 4, and the distance and the vector in the step 6.
Description
Technical Field
The invention relates to the technical field of computer vision, in particular to a method for measuring the distance between grid construction nodes.
Background
Along with the increasing scale of net rack building construction, the number is more and more, and accidents frequently occur due to the lack of necessary safety monitoring and early warning measures, so that great losses are caused to people, life and property and economic property of the country. Therefore, the space measuring method of the grid structure nodes is researched, the safety condition of the grid structure is measured and evaluated, potential safety hazards are found in time, and the important social and economic significance is provided for guaranteeing the safety operation of the large-scale grid structure. At present, engineering quality acceptance is difficult to carry out after the net rack building is built, and after a certain period of use, the quality of the net rack building cannot be evaluated, because the method mainly comprises the following steps: the manual detection method not only needs a large amount of manpower and material resources, but also can only realize the spot inspection, so that the comprehensive quality of the net rack building cannot be ensured, but the collapse of the whole building is caused once three nodes of the net rack building are in question; the nondestructive ultrasonic crack detection has higher accuracy, but is limited by the complex structure of the grid structure, so that the nondestructive ultrasonic crack detection is not suitable for all grid structure detection; the foreign net rack detection equipment is expensive and is not suitable for all enterprises.
Disclosure of Invention
In order to overcome the technical problems, the invention aims to provide the space measurement method for the grid construction nodes, which can acquire steel structure images through a variable-focus high-definition camera, then realize high-precision space measurement for the grid construction nodes by adopting a target detection algorithm, a laser range finder and an attitude sensor, further judge whether the grid construction structure is abnormal or not based on the space data, and ensure the real-time performance and the accuracy of safety monitoring of a large-scale grid construction. In addition, the space data of the grid construction nodes are analyzed by utilizing edge calculation in a multi-dimensional mode, valuable information is deeply mined, and unsafe factors of the grid construction are eliminated to a great extent.
In order to achieve the above purpose, the technical scheme adopted by the invention is as follows:
a space measurement method of grid construction nodes comprises the following steps of;
Step 1): resetting the variable-focus high-definition camera, the laser range finder and the gesture sensor device;
step 2): loading a target detection model, collecting an image of a net rack building by using a variable-focus high-definition camera, and detecting adjacent bolt balls Q 1 and Q 2 in the image by using the loaded target detection model;
Step 3): adjusting the posture of the laser range finder by the relative positions of the bolt ball and the laser spot of the laser range finder in the image of the grid frame building, and finally enabling the laser spot of the laser range finder to coincide with the circle center of the bolt ball Q 1;
Step 4): obtaining the distance L 1 from the laser range finder to the bolt ball Q 1, calculating the horizontal angle theta 1 and the vertical angle theta 2 of the attitude sensor to obtain a vector
Step 5): adjusting the posture of the laser range finder by the relative positions of the bolt ball and the laser spot of the laser range finder in the image of the grid frame building, and finally enabling the laser spot of the laser range finder to coincide with the center of the nearest bolt ball Q 2 at the left lower part of the bolt ball Q 1;
Step 6): obtaining the distance L 2 from the laser range finder to the bolt ball Q 2, calculating the horizontal angle theta 3 and the vertical angle theta 4 of the attitude sensor to obtain a vector
Step 7): through the distance L 1 and the vector in the step 4Distance L 2 and vector/>, above in step 6And calculating the distance L of the steel beam between the two bolt balls, so as to judge whether the steel beam is deformed.
The step1 of collecting the image of the net rack building by using the variable-focus high-definition camera specifically comprises the following steps:
step 1.1: resetting the focal length of the variable-focus high-definition camera, and resetting a motor M 1 of a hollow rotary platform where the variable-focus high-definition camera is positioned;
step 1.2: resetting the laser focal length of the laser range finder and resetting a motor M 2、M3 of a hollow rotating platform where the laser sensor is positioned;
Step 1.3: resetting the whole hollow rotary platform motor M 4 where the variable-focus high-definition camera and the laser range finder are positioned;
step 1.4: the variable-focus high-definition camera starts to adjust the focal length and collect images.
The step 2 of detecting the adjacent bolt balls Q 1 and Q 2 in the image by using the loaded object detection model specifically includes:
Step 2.1: loading target detection model weights by using an embedded AI core plate;
Step 2.2: the focal length of the variable-focus high-definition camera is adjusted, meanwhile, an image of a net rack building is collected, the collected image is input into a target detection network to carry out target detection until 5-8 target bolt balls are detected;
Step 2.3: and determining bolt balls Q 1 and Q 2 to be detected, and fine-adjusting the focal length of the variable-focus high-definition camera to enable the bolt ball Q 1 to clearly appear in the field of view of the variable-focus high-definition camera.
The step 3 is to make the laser spot of the laser range finder coincide with the center of the circle where the bolt ball Q 1 is located specifically:
Step 3.1: adjusting the motors M 2 and M 3 until the laser beam of the laser ranging can be mapped to the bolt ball;
Step 3.2: adjusting the focal length of the laser beam of the laser range finder to reduce the spots of the laser beam;
step 3.3: the motors M 2, M 3 are adjusted until the laser beam of the laser rangefinder can be mapped to the center of the bolt ball.
The vector is calculated in the step 4The method comprises the following steps:
x1＝L1*cosθ1cosθ2
y1＝L1*sinθ1cosθ2
z1＝L1*sinθ2
x 1: vector quantity X-axis coordinates of (a)
Y 1: vector quantityY-axis coordinates of (c)
Z 1: vector quantityIs the z-axis coordinate of (2)
The specific step of enabling the laser spot of the laser range finder to coincide with the center of the nearest bolt ball Q 2 of the bolt ball Q 1 in the step 5 is as follows:
step 5.1: judging the relative position of the bolt ball Q 2 and the laser spot through the image;
step 5.2: adjusting the motors M 2 and M 3 until the laser beam of the laser ranging can be mapped to the spherical center direction of the bolt ball Q 2;
Step 5.3: adjusting the focal length of the laser beam to reduce the spot of the laser beam;
step 5.4: motor M 2 is adjusted and motor M 3 is adjusted until the laser beam of the laser range can be mapped to the center of bolt ball Q 2.
The vector is calculated in the step 6The method comprises the following steps:
x2＝L2*cosθ3cosθ4
y2＝L2*sinθ3cosθ4
z2＝L2*sinθ4
x 2: vector quantity X-axis coordinates of (a)
Y 2: vector quantityY-axis coordinates of (c)
Z 2: vector quantityIs the z-axis coordinate of (2)
The calculation formula of the distance L in the step7 is as follows:
The invention has the beneficial effects that:
According to the invention, the high-precision laser range finder, the multi-axis 0.001-degree attitude sensor and the deep learning target detection algorithm are effectively combined, so that the measurement method of the grid building nodes is not dependent on manual monitoring, the measurement efficiency and the measurement precision are improved, the high-precision measurement of the grid building node spacing is realized, whether the grid building structure is abnormal or not is judged based on the spacing data, and the real-time performance and the accuracy of the safety monitoring of the large grid building are ensured. In addition, the measuring method is not limited by application scenes, and can be suitable for various complex environments and scenes which cannot be monitored manually.
The method provided by the invention has the advantages of high measurement precision, low time cost and economic cost, and can realize high-precision measurement of the spacing between grid construction nodes in a complex environment.
Drawings
FIG. 1 is a flow chart of the method of the present invention.
Fig. 2 is a schematic diagram of calculating an adjustment angle of a laser range finder according to the present invention.
FIG. 3 is a schematic illustration of the calculation of the spacing between adjacent bolt balls according to the present invention.
Detailed Description
The present invention will be described in further detail with reference to examples.
Detailed description of specific steps of the present invention will be described with reference to fig. 1,2 and 3, fig. 1 being a flow chart of the present method.
Step 1): resetting equipment such as a camera, a laser range finder, an attitude sensor and the like;
Step 1.1: resetting the focal length of the camera, resetting a motor M1 of a hollow rotary platform where the camera is positioned, and enabling reset photoelectric switching light corresponding to the hollow rotary platform to be in a closed state;
Step 1.2: resetting the laser focal length of the laser range finder to enable the laser beam to be in a divergent state, resetting a motor M 2、M3 of a hollow rotating platform where the laser sensor is located to enable the hollow rotating platforms of the two devices to be in a resetting state;
step 1.3: resetting the whole hollow rotary platform motor M 4 where the camera and the laser range finder are positioned;
step 1.4: the camera begins to intermittently expand the focal length and capture images.
Step 2): loading a target detection model, acquiring an image of a net rack building by using a variable-focus high-definition camera, and detecting adjacent bolt balls Q 1 and Q 2 in the image by using the loaded target detection model;
Step 2.1: loading YOLOv bolt ball target detection model by using a Hua HISI3519 embedded AI core plate;
Step 2.2: the focal length of the variable-focus high-definition camera is adjusted, an image of a net rack building is collected, the collected image is sent to a target detection network for identification until the number of bolt balls in the image is more than 5 and less than 8, and the image is shown in a flow chart of FIG. 1;
Step 2.3: the bolt balls Q 1 and Q 2 to be detected are determined, and the focal length of the camera is finely tuned so that the bolt ball Q 1 can appear clearly in the field of view of the camera.
Step 3): adjusting the posture of the laser range finder by the relative positions of the bolt ball and the laser spot of the laser range finder in the steel structure image, and finally enabling the laser spot of the laser range finder to coincide with the circle center of the bolt ball Q 1;
Step 3.1: adjusting the motor M 2 and the motor M 3 until the laser beam of the laser ranging can be mapped to the bolt ball;
step 3.2: gradually reducing the focal length of the laser beam and reducing the spots of the laser beam;
Step 3.3: repeating steps 3.1 and 3.2 until the laser beam of the laser range finder can be completely mapped to the sphere center of the bolt ball and the laser beam of the laser range finder is focused to the minimum state;
Step 4): obtaining the distance L 1 from the laser range finder to the bolt ball Q 1, calculating the horizontal angle theta 1 and the vertical angle theta 2 of the attitude sensor to obtain a vector As shown in fig. 2;
The coordinates of the vector are calculated by the following formula:
x1＝L1*cosθ1cosθ2
y1＝L1*sinθ1cosθ2
z1＝L1*sinθ2
step 4.1: calculating the mapping of the laser beam in the horizontal direction to obtain the horizontal direction distance:
L11＝L1*cosθ2
and (5) obtaining vertical direction coordinates:
z1＝L1*sinθ2
Coordinates in the x-axis and y-axis directions are calculated from the distance L 11 in the horizontal direction:
x1＝L11*cosθ1
y1＝L11*sinθ1
Step 5): and adjusting the posture of the laser range finder by the relative positions of the bolt ball in the steel structure image and the laser spot of the laser range finder in the image, and finally enabling the laser spot of the laser range finder to coincide with the center of the nearest bolt ball Q 2 of the bolt ball Q 1.
Step 5.1: judging the relative position of the bolt ball Q 2 and the laser spot through the image, so as to judge the direction of the laser gesture to be adjusted;
Step 5.2: adjusting the motor M 3 and the motor M 4 until the laser beam of the laser ranging can be mapped to the spherical center direction of the bolt ball Q 2;
Step 5.3: adjusting the focal length of the laser beam to reduce the spot of the laser beam;
Step 5.4: motor M 3 is adjusted and motor M 4 is adjusted until the laser beam of the laser range can be mapped to the center of bolt ball Q 2.
Step 6): obtaining the distance L 2 from the laser range finder to the bolt ball Q 2, calculating the horizontal angle theta 3 and the vertical angle theta 4 of the attitude sensor to obtain a vectorThe calculation mode is the same as that of the step 4;
step 7): through the distance L 1 and the vector in the step 4 Distance L 2 and vector/>, above in step 6The distance L between the two bolt balls is obtained, a schematic diagram is shown in fig. 3, and the calculation formula is as follows:
the vector calculated by step 4 and step 6 And calculating a cosine value cos theta of the vector included angle, and then calculating the other side length of the space plane triangle by using a cosine theorem.
Claims (8)
1. The method for measuring the space between the grid construction nodes is characterized by comprising the following steps of;
Step 1): resetting the variable-focus high-definition camera, the laser range finder and the gesture sensor device;
step 2): loading a target detection model, collecting an image of a net rack building by using a variable-focus high-definition camera, and detecting adjacent bolt balls Q 1 and Q 2 in the image by using the loaded target detection model;
Step 3): adjusting the posture of the laser range finder by the relative positions of the bolt ball and the laser spot of the laser range finder in the image of the grid frame building, and finally enabling the laser spot of the laser range finder to coincide with the circle center of the bolt ball Q 1;
Step 4): obtaining the distance L 1 from the laser range finder to the bolt ball Q 1, calculating the horizontal angle theta 1 and the vertical angle theta 2 of the attitude sensor to obtain a vector
Step 5): adjusting the posture of the laser range finder by the relative positions of the bolt ball and the laser spot of the laser range finder in the image of the grid frame building, and finally enabling the laser spot of the laser range finder to coincide with the center of the nearest bolt ball Q 2 at the left lower part of the bolt ball Q 1;
Step 6): obtaining the distance L 2 from the laser range finder to the bolt ball Q 2, calculating the horizontal angle theta 3 and the vertical angle theta 4 of the attitude sensor to obtain a vector
Step 7): through the distance L 1 and the vector in the step 4Distance L 2 and vector/>, above in step 6And calculating the distance L of the steel beam between the two bolt balls, so as to judge whether the steel beam is deformed.
2. The method for measuring the space between nodes of a network frame building according to claim 1, wherein the step 1 of capturing the image of the network frame building by using the variable-focus high-definition camera specifically comprises:
step 1.1: resetting the focal length of the variable-focus high-definition camera, and resetting a motor M 1 of a hollow rotary platform where the variable-focus high-definition camera is positioned;
step 1.2: resetting the laser focal length of the laser range finder and resetting a motor M 2、M3 of a hollow rotating platform where the laser sensor is positioned;
Step 1.3: resetting the whole hollow rotary platform motor M 4 where the variable-focus high-definition camera and the laser range finder are positioned;
step 1.4: the variable-focus high-definition camera starts to adjust the focal length and collect images.
3. The method for measuring the distance between nodes of a grid structure according to claim 1, wherein the step 2 uses the loaded object detection model to detect the adjacent bolt balls Q 1 and Q 2 in the image specifically comprises:
Step 2.1: loading target detection model weights by using an embedded AI core plate;
Step 2.2: the focal length of the variable-focus high-definition camera is adjusted, meanwhile, an image of a net rack building is collected, the collected image is input into a target detection network to carry out target detection until 5-8 target bolt balls are detected;
Step 2.3: and determining bolt balls Q 1 and Q 2 to be detected, and fine-adjusting the focal length of the variable-focus high-definition camera to enable the bolt ball Q 1 to clearly appear in the field of view of the variable-focus high-definition camera.
4. The method for measuring the distance between grid construction nodes according to claim 1, wherein the step 3 is characterized in that the overlapping of the laser spot of the laser range finder and the center of the circle where the bolt ball Q 1 is located is specifically:
Step 3.1: adjusting the motors M 2 and M 3 until the laser beam of the laser ranging can be mapped to the bolt ball;
Step 3.2: adjusting the focal length of the laser beam of the laser range finder to reduce the spots of the laser beam;
step 3.3: the motors M 2, M 3 are adjusted until the laser beam of the laser rangefinder can be mapped to the center of the bolt ball.
5. The method for measuring the distance between nodes of a grid structure according to claim 1, wherein the vector is calculated in the step 4The method comprises the following steps:
x1＝L1*cosθ1cosθ2
y1＝L1*sinθ1cosθ2
z1＝L1*sinθ2
x 1: vector quantity X-axis coordinates of (a)
Y 1: vector quantityY-axis coordinates of (c)
Z 1: vector quantityIs defined by the z-axis coordinate of (c).
6. The method for measuring the space between grid construction nodes according to claim 1, wherein the specific step of overlapping the laser spot of the laser range finder with the center of the nearest bolt ball Q 2 of the bolt ball Q 1 in step 5 is:
step 5.1: judging the relative position of the bolt ball Q 2 and the laser spot through the image;
step 5.2: adjusting the motors M 2 and M 3 until the laser beam of the laser ranging can be mapped to the spherical center direction of the bolt ball Q 2;
Step 5.3: adjusting the focal length of the laser beam to reduce the spot of the laser beam;
step 5.4: motor M 2 is adjusted and motor M 3 is adjusted until the laser beam of the laser range can be mapped to the center of bolt ball Q 2.
7. The method for measuring the distance between nodes of a grid structure according to claim 1, wherein the vector is calculated in the step 6The method comprises the following steps:
x2＝L2*cosθ3cosθ4
y2＝L2*sinθ3cosθ4
z2＝L2*sinθ4
x 2: vector quantity X-axis coordinates of (a)
Y 2: vector quantityY-axis coordinates of (c)
Z 2: vector quantityIs defined by the z-axis coordinate of (c).
8. The method for measuring the distance between nodes of a grid structure according to claim 1, wherein the distance L in the step 7 is calculated as follows:
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210681992.3A CN115046488B (en) | 2022-06-16 | 2022-06-16 | Space measurement method for grid construction nodes |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210681992.3A CN115046488B (en) | 2022-06-16 | 2022-06-16 | Space measurement method for grid construction nodes |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN115046488A CN115046488A (en) | 2022-09-13 |
| CN115046488B true CN115046488B (en) | 2024-06-14 |
Family
ID=83160754
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210681992.3A Active CN115046488B (en) | 2022-06-16 | 2022-06-16 | Space measurement method for grid construction nodes |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115046488B (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105444687A (en) * | 2015-11-30 | 2016-03-30 | 中国人民解放军国防科学技术大学 | Relative pose change measuring method based on eye-to-eye shooting measurement and laser ranging |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| AT506110B1 (en) * | 2007-12-12 | 2011-08-15 | Nextsense Mess Und Pruefsysteme Gmbh | DEVICE AND METHOD FOR DETECTING BODY MEASURE DATA AND CONTOUR DATA |
| CN105787933B (en) * | 2016-02-19 | 2018-11-30 | 武汉理工大学 | Water front three-dimensional reconstruction apparatus and method based on multi-angle of view point cloud registering |
| CN110360957B (en) * | 2019-08-22 | 2021-06-08 | 惠州市新一代工业互联网创新研究院 | Angular deformation measuring method for H-shaped steel structure in hot working process |
-
2022
- 2022-06-16 CN CN202210681992.3A patent/CN115046488B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN105444687A (en) * | 2015-11-30 | 2016-03-30 | 中国人民解放军国防科学技术大学 | Relative pose change measuring method based on eye-to-eye shooting measurement and laser ranging |
Non-Patent Citations (1)
| Title |
|---|
| 激光测距仪与相机信息融合过程中位姿标定方法;王鹤;李泽明;;红外与激光工程;20200425(第04期);全文 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN115046488A (en) | 2022-09-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR101309443B1 (en) | Apparatus and method for monitoring a structure using motion capture method | |
| Poorghasem et al. | Review of robot-based automated measurement of vibration for civil engineering structures | |
| CN105547635A (en) | Non-contact type structural dynamic response measurement method for wind tunnel test | |
| Chen et al. | Color and depth data fusion using an RGB‐D sensor for inexpensive and contactless dynamic displacement‐field measurement | |
| CN110186383B (en) | Monocular camera deflection measuring method based on target point elevation angle change | |
| CN113793367B (en) | Visual measurement and power identification system and method for engineering structure corner displacement | |
| CN104063863B (en) | The lower facedown binocular vision system and image processing method monitored for river course | |
| CN106096207A (en) | A kind of rotor wing unmanned aerial vehicle wind resistance appraisal procedure based on multi-vision visual and system | |
| CN111385558B (en) | TOF camera module precision measurement method and system thereof | |
| Zhang et al. | Multi-point displacement monitoring based on full convolutional neural network and smartphone | |
| CN113884011A (en) | Non-contact concrete surface crack measuring equipment and method | |
| CN103954220A (en) | Ship motion state digital image measuring method in bridge collision test | |
| CN112330740A (en) | Pseudo-binocular dynamic distance measurement method based on monocular video | |
| Yan et al. | Multi-line laser structured light fast visual positioning system with assist of TOF and CAD | |
| CN118500353A (en) | Hyperbolic cooling tower inclination state identification method based on laser point cloud data | |
| CN115046488B (en) | Space measurement method for grid construction nodes | |
| Jiang et al. | Bridge Deformation Measurement Using Unmanned Aerial Dual Camera and Learning‐Based Tracking Method | |
| CN113777111A (en) | Multi-dimensional detection device for structural defects of large-diameter diversion tunnel | |
| WO2024067435A1 (en) | Video-based multi-object displacement tracking monitoring method and apparatus | |
| Li et al. | Self-calibrating technique for 3D displacement measurement using monocular vision and planar marker | |
| CN106323335B (en) | Reconfigurable indoor mobile robot navigation performance evaluation instrument and evaluation method thereof | |
| Zhang et al. | A cross structured light sensor for weld line detection on wall-climbing robot | |
| Lee et al. | Vision-based 6-DOF displacement measurement of structures with a planar marker | |
| CN205300519U (en) | Iron tower warp measuring device | |
| Lim et al. | Differential settlement monitoring system using inverse perspective mapping |
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 |