An automatic cloth distributing machine and method based on infrared laser and computer vision

Abstract

This invention relates to an automatic concrete placing machine and method based on infrared laser and computer vision. The concrete placing machine includes a central shaft, a feed tube, a main telescopic arm, a rigid feed tube, infrared lasers, a camera, a drive device, and a control center. One end of the main telescopic arm and one end of the feed tube are rotatably mounted on the central shaft, while the camera and the rigid feed tube are mounted on the other end of the main telescopic arm. The rigid feed tube is perpendicular to the main telescopic arm. Two infrared lasers are mounted on both sides of the rigid feed tube. The infrared lasers and the camera collect the planar information of the rebar and transmit it to the control center, which controls the opening and closing of the drive device. Compared with the prior art, this invention can achieve concrete placing without manual operation, with a high degree of automation. This invention accurately obtains the position of the rebar and accurately places it by collecting the planar information of the rebar through the camera and infrared laser, resulting in more uniform concrete placement.

Description

Technical Field

[0001] This invention relates to construction tools, and more particularly to an automatic concrete placing machine and method based on infrared laser and computer vision. Background Technology

[0002] With the development of the construction industry, traditional construction techniques are actively transforming towards digitalization and intelligentization. In bridge construction, the pouring of bridge towers is crucial, determining the bridge's strength. The concrete placing boom is an important tool for bridge tower pouring, and its efficiency determines the construction period. Using intelligent technologies to automate the concrete placing boom can effectively improve construction efficiency.

[0003] Traditional concrete placing booms rely on manual adjustment of the placing tube. Due to uneven reinforcement distribution, it is difficult to obtain the center point during placing, which can easily lead to uneven placement and poor bridge tower quality.

[0004] Authorization notice number CN209657113U discloses a concrete placing boom control device and a concrete placing boom, which addresses the inconvenience caused by existing concrete placing boom control devices and concrete placing booms having only one control system. Furthermore, in the concrete placing boom control device and concrete placing boom, the two control systems can work independently or collaboratively, improving the flexibility of controlling the concrete placing boom. However, the control device still requires manual adjustment and is not well-suited for bridge construction.

[0005] Application publication number CN118223406A discloses a combined bridge tower pouring device and its construction method based on a large hopper and a variable-amplitude conveyor belt. The device includes a large hopper, a tower top hopper support frame, a rotatable and variable-amplitude concrete conveyor belt, and a conveyor belt support frame. This improves the efficiency of concrete pouring for combined bridge towers and the uniformity of concrete distribution, ensuring safety during tower top construction. The method uses a dual-pipe pouring system, resulting in high pouring efficiency. However, in this prior art, the material feeding pipe has poor adaptability to complex reinforcing bars, making it difficult to obtain the center point, thus affecting the uniformity of material feeding.

[0006] In summary, the technical problem that needs to be solved is how to design a fabric spreading machine that provides uniform fabric distribution and a high degree of automation. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art, such as uneven fabric distribution or low degree of automation, and to provide an automatic fabric distribution machine and method based on infrared laser and computer vision.

[0008] The objective of this invention can be achieved through the following technical solutions:

[0009] According to one aspect of the present invention, an automatic concrete placing machine based on infrared laser and computer vision is provided for placing concrete on a plane of reinforcing bars. The placing machine includes a central shaft, a material extraction tube, a main telescopic arm, a rigid material discharge tube, infrared lasers, a camera, a drive device, and a control center. One end of the main telescopic arm and one end of the material extraction tube are rotatably mounted on the central shaft, and the camera and the rigid material discharge tube are mounted on the other end of the main telescopic arm. The rigid material discharge tube is perpendicular to the main telescopic arm. Two infrared lasers are mounted on both sides of the rigid material discharge tube.

[0010] The central shaft, material extraction pipe, main telescopic arm, and rigid unloading pipe are connected to the drive device; the infrared laser, camera, and drive device are electrically connected to the control center. The infrared laser and camera collect the plane information of the steel bars and transmit it to the control center. The control center controls the opening and closing of the drive device.

[0011] As a preferred technical solution, the fabric placing machine also includes two auxiliary telescopic arms arranged symmetrically about the main telescopic arm as the axis of symmetry. One end of each auxiliary telescopic arm is connected to the central shaft, and the other end is equipped with an infrared laser. The auxiliary telescopic arms are the same length as the main telescopic arm.

[0012] As a preferred technical solution, the axis of the rigid feed tube coincides with the axis of the camera's field of view.

[0013] According to another aspect of the present invention, a fabric placement method using an automated fabric placement machine based on infrared laser and computer vision is provided, specifically including the following steps:

[0014] Step S1: The drive device drives the central shaft to rotate in the first direction, and the camera and infrared laser collect the current steel bar plane information and transmit it to the control center;

[0015] Step S2: The control center calculates the current positional relationship between the rebar plane and the concrete placing machine based on the collected information.

[0016] Step S3: The control center calculates the material feeding point based on the positional relationship and controls the drive device to drive the central shaft, main telescopic arm and rigid feeding pipe to feed material at the material feeding point;

[0017] Step S4: Determine if the central axis has rotated one revolution. If yes, proceed to step S5; otherwise, return to step S1.

[0018] Step S5: Determine whether all material feeding is complete. If yes, stop the material feeder; otherwise, change the extension length of the main telescopic arm and return to step S1.

[0019] As a preferred technical solution, step S1 specifically includes the following steps:

[0020] Step S101: The camera captures a planar image of the current reinforcing steel bars and transmits it to the control center;

[0021] Step S102: Record the current initial position, rotate the central axis, stop rotating when the infrared laser detects the rebar, and record the angle through which the central axis rotates.

[0022] As a preferred technical solution, step S2 specifically includes the following steps:

[0023] Step S201: The control center processes the current rebar plane image to obtain a rebar distribution image;

[0024] In step S202, the control center calculates the positional relationship between the current rebar plane and the concrete placing machine based on the rebar distribution image and the angle through which the infrared laser rotates.

[0025] As a preferred technical solution, step S201 specifically includes the following steps:

[0026] Step S2011: Based on the relative height difference between the camera and the bottom of the rigid feeding pipe and the camera focal length, obtain the ratio k of the distance on the image of the bottom position of the rigid feeding pipe on the rebar plane image to the actual distance.

[0027] Step S2012: Based on the Canny edge detection algorithm, extract the outline of the reinforcing bars to obtain the reinforcing bar distribution image.

[0028] As a preferred technical solution, step S202 specifically includes the following steps:

[0029] Step S2021: Based on the rebar distribution image, obtain the straight line l1 where the rebar is detected by the infrared laser, the axis O1 of the rigid feed pipe, and the axis l2 of the camera's field of view;

[0030] Step S2022: Based on plane geometry, determine the position of the central axis of the reinforcing bar in the plane, and then obtain the radius R of the reinforcing bar in the plane. 真 ;

[0031] Step S2023, according to R 真 The relationship between the fabric radius R of the fabric placing machine and the fabric distribution machine is used to obtain the dimensional correction coefficient k. 真 This allows us to obtain the positional relationship between the steel bar plane and the concrete placing machine.

[0032] As a preferred technical solution, step S3 specifically includes the following steps:

[0033] Step S301: Based on the current positional relationship between the rebar plane and the concrete placing machine, fix the length of the main telescopic arm and trace the trajectory of the rigid feeding pipe in the current rebar plane after rotating around the central axis in the first direction.

[0034] Step S302: Extract the intersection points of the reinforcing bars and the trajectory within the current reinforcing bar plane;

[0035] Step S303: The midpoint of the two nearest adjacent intersections of the rigid feed pipe in the first direction is the feeding point. The control center calculates the angle through which the central axis rotates to reach the feeding point.

[0036] Step S304: The drive device drives the central shaft and the rigid feeding pipe to convey materials.

[0037] As a preferred technical solution, in step S304, the amount M of material fed to each feeding point is: M = α 总 ·m;

[0038] Where, α 总 α is the total angle rotated through the central axis. 总 =α1+α2; m is the unit feed amount; α1 is the angle through which the central axis rotates from the current position to when the infrared laser detects the steel bar; the position of the central axis when the infrared laser detects the steel bar is defined as the first position, and α2 is the angle through which the central axis rotates from the first position to the feeding point.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] 1) The automatic material placing machine provided by this invention can place materials without manual operation, with a high degree of automation; it collects the plane information of the steel bars through a camera and an infrared laser, accurately obtains the position of the steel bars and accurately places them, resulting in more uniform material placement;

[0041] 2) The rotation of the central shaft of this invention drives the camera and infrared laser to collect information on the current position of the steel bar plane, and feeds the material according to the positional relationship between the current steel bar plane and the concrete placing machine. The material feeding position is highly accurate. The rotating method of feeding material layer by layer makes it less likely to cause omissions, which is especially suitable for the casting of circular bridge towers.

[0042] 3) The present invention determines the material quantity based on the angle through which the central axis rotates, i.e. the distance between the steel bars, which makes the material quantity more accurate and further improves the uniformity of material distribution. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the overall structure of an automatic fabric feeding machine based on infrared laser and computer vision according to the present invention.

[0044] Figure 2 This is a schematic diagram showing the arrangement of the main telescopic arm and the auxiliary telescopic arm of the present invention;

[0045] Figure 3 This is a flowchart of the fabric application method of the present invention;

[0046] Figure 4This is a schematic diagram of the outline of the reinforcing bars in this invention;

[0047] Figure 5 This is a schematic diagram illustrating the calculation of the positional relationship between the current rebar plane and the concrete placing machine according to the present invention;

[0048] Figure 6 This is a schematic diagram showing the trajectory of the rigid feed tube of the present invention in the current steel bar plane after rotating about the central axis along the first direction;

[0049] The numbers in the diagram are as follows:

[0050] 1. Central shaft, 2. Feed tube, 3. Main telescopic arm, 4. Rigid feed tube, 5. Infrared laser, 6. Camera, 7. Secondary telescopic arm. Detailed Implementation

[0051] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0052] Example 1

[0053] like Figure 1 As shown, the present invention provides an automatic material placing machine based on infrared laser and computer vision for placing material on a steel bar plane, including a central shaft 1, a material extraction pipe 2, a main telescopic arm 3, a rigid material feeding pipe 4, two infrared lasers 5, a camera 6, two auxiliary telescopic arms 7, a drive device, and a control center.

[0054] The central shaft 1 is connected to one end of the main telescopic arm 3, one end of the extraction pipe 2, and one end of the auxiliary telescopic arm 7. The central shaft 1 can rotate, which in turn can drive the main telescopic arm 3, the extraction pipe 2, and the auxiliary telescopic arm 7 to rotate.

[0055] The material extraction pipe 2 is used to extract the raw material to be laid, which is concrete in the building pouring.

[0056] The length of the main telescopic boom 3 is R, which is the material feeding radius of the concrete placing boom. The adjustable range of the boom length is R1 to R2, so the material feeding radius of the concrete placing boom is [R1, R2]. According to the actual size requirements of the steel bar plane, the material feeding range can be changed by changing the length of the main telescopic boom 3.

[0057] The rigid feeding tube 4 can prevent severe shaking during the feeding process from causing inaccurate feeding position.

[0058] Camera 6 and rigid feed tube 4 are installed at the other end of the main telescopic arm 3. To ensure sufficient stability, the rigid feed tube 4 is perpendicular to the main telescopic arm 3 and does not sway during feeding. The perpendicularity requirement is ±1°. The field of view of camera 6 is facing the plane of the steel bar, and the axis of rigid feed tube 4 coincides with the axis of the field of view of camera 6.

[0059] like Figure 2 As shown, the two auxiliary telescopic arms 7 are arranged symmetrically about the main telescopic arm 3, and the length of the auxiliary telescopic arms 7 is the same as that of the main telescopic arm 3.

[0060] Two infrared lasers 5 are distributed and installed at one end of the two auxiliary telescopic arms 7 and on both sides of the rigid feed tube 4. They include laser emitters and laser receivers and can emit and receive lasers.

[0061] The drive unit connects the central shaft 1, the material extraction pipe 2, the main telescopic arm 3, and the rigid discharge pipe 4. It is used to drive the central shaft 1 to rotate, the material extraction pipe 2 to extract material, the main telescopic arm 3 to extend and retract, and the rigid discharge pipe 4 to discharge material.

[0062] The control center is electrically connected to camera 6, infrared laser 5, and drive unit, supporting image processing and related algorithm calculations. Images captured by camera 6 and signals collected by infrared laser 5 are transmitted to the control center for determining and identifying the planar position of the rebar. The drive unit receives commands from the control center to drive the central shaft 1, the extraction tube 2, the main telescopic arm 3, and the rigid unloading tube 4. Optional component configurations for the control center include: a computing server, a storage server, and an RTX4090 GPU; other components with image processing or algorithm calculation capabilities can be arbitrarily replaced.

[0063] Example 2

[0064] like Figure 3 As shown, the present invention provides an automatic material placement method based on infrared laser and computer vision, employing an automatic material placement machine based on infrared laser and computer vision.

[0065] Step 1: The automatic concrete placing machine's camera 6 captures the current planar image of the rebar and transmits it to the control center. Based on the height difference h0 between the automatic concrete placing machine's camera 6 and the bottom of the rigid feeding tube 4, and the focal length f of the camera 6 (which can be a monocular camera), the ratio k of the distance on the image to the actual distance at the bottom of the rigid feeding tube 4 is calculated.

[0066] k = f / h0

[0067] Based on the Canny edge detection algorithm, the contours of the reinforcing bars in the image are extracted to obtain the reinforcing bar distribution image. The specific operation process is as follows:

[0068] 1) Input a planar image of the reinforcing bars, and convert the original image to grayscale using OpenCV's built-in functions;

[0069] 2) Based on Gaussian filtering, image noise is removed to avoid misidentifying noise as edges during edge detection. The 3×3 convolution kernel template is as follows:

[0070]

[0071] The dimension of the filter kernel should not be too large, otherwise it may smooth out the edge information, making the edge detection operator unable to correctly identify the edge information;

[0072] 3) First-order finite difference is used to calculate the amplitude and direction, suppressing non-maximum data. The calculation method is as follows:

[0073] Using the Sobel operator as the gradient operator, we can obtain two 3×3 matrices N of the partial derivatives of the image in the x and y directions. y and N x H(i,j) is the image to be calculated.

[0074]

[0075] Where c is the gradient to be calculated;

[0076] Find the gradients in the x and y directions:

[0077] g x =N x ·H(i,j) T g y =N y ·H(i,j) T

[0078] The gradient magnitude and direction here are:

[0079] θ = arctan(g) y / g x )

[0080] 4) Use dual thresholding to filter the binarized image. By selecting appropriate large and small thresholds, the edge image closest to the true edge of the image is obtained. The specific implementation steps are as follows:

[0081] (1) An edge image is obtained based on a high threshold. Since the threshold is high, the resulting image edges may not be closed.

[0082] (2) In the high-threshold image, the edges are linked into contours. When the endpoint of the contour is reached, the algorithm will search for a point that meets the low threshold in the 8 neighborhood points of the breakpoint, and then collect new edges based on this point until the entire image edge is closed.

[0083] Step 2: The control center controls the intermediate shaft to rotate clockwise or counterclockwise while keeping the material feeding radius unchanged. When the infrared laser 5 detects the steel bar, it stops rotating. Step 1 is executed again. The camera 6 acquires the current plane image of the steel bar and records the angle α1 through which the central shaft 1 rotates.

[0084] Based on the information collected by infrared laser 5 and the current rebar plane image collected by camera 6, the positional relationship between the current rebar plane and the concrete placing machine is calculated. The specific operation process is as follows:

[0085] 1) such as Figure 4 As shown, based on the outline of the steel bar in the image, the straight line l1 where the laser mutation point A is located in the image (i.e. the straight line where the steel bar is located detected by the infrared laser 5), the included angle α0 between the auxiliary rotating arm and the main rotating arm, the feed pipe axis O1, and the axis l2 of the field of view of the camera 6 are obtained.

[0086] 2) such as Figure 5 As shown, given α0, O1, l1, and l2, establish a rectangular coordinate system based on plane geometry and solve for the radius R of the steel reinforcement in the plane dimension. 真 ;

[0087] 3) According to R 真 The dimensional correction coefficient k is obtained by comparing it with the actual fabric radius R. 真 =R / R 真 This yields the positional relationship between the rebar plane and the concrete placing boom;

[0088] like Figure 6 As shown, given the distance R from the central axis 1 to the center of the feed tube, based on the position of the feed tube center in the image and the actual scale mapping relationship k... 真 The position O2 of the central axis 1 is obtained; with O2 as the center, R 真 Using the radius as the reference, obtain the path trajectory curve of the rigid feed tube 4 after rotating along the first direction in the current rebar plane, and then obtain the intersection point of the trajectory curve and the contour; given the two intersection points j1 and j2 on the path trajectory curve that are closest to the current position, obtain... Corresponding to the central angle α′, the next feed point position j3 is located at At the midpoint, the angle of rotation required from the current position to j3 is α2; the drive device drives the central shaft 1 and the rigid feeding tube 4 to feed materials, completing a single feeding operation, and records the rotation angle α for each feeding process. 总 =α1+α2, set the unit feed rate m, and the single feed rate M = m·α 总 Repeat steps 1 and 2 to complete the unloading within the current length range of the main telescopic arm 3;

[0089] When the cumulative rotation angle reaches 360°, that is, after the intermediate shaft has rotated one revolution, stop rotating and control the main and auxiliary telescopic arms 7 to extend and retract synchronously, changing R. The change range is controlled by the specific size of the pier and can be set to 5 levels. The radius change of each level is ΔR = (R2 - R1) / 5, where R1 and R2 are the adjustable limit values ​​of the main telescopic arm 3. Repeat steps 1 and 2 until the 5 levels of pouring are completed, and the management personnel evaluate the pouring effect.

[0090] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A fabric placement method for an automatic fabric placement machine based on infrared laser and computer vision, characterized in that... ， An automatic material placing machine based on infrared laser and computer vision is used for placing materials on a steel bar plane. The material placing machine includes a central shaft (1), a material extraction pipe (2), a main telescopic arm (3), a rigid material discharge pipe (4), an infrared laser (5), a camera (6), a drive device, and a control center. The central shaft (1) is rotatable. One end of the main telescopic arm (3) and one end of the material extraction pipe (2) are mounted on the central shaft (1), and the camera (6) and the rigid material discharge pipe (4) are mounted on the other end of the main telescopic arm (3). The rigid material discharge pipe (4) is perpendicular to the main telescopic arm (3). There are two infrared lasers (5), which are mounted on both sides of the rigid material discharge pipe (4). The central shaft (1), the material extraction pipe (2), the main telescopic arm (3) and the rigid material discharge pipe (4) are connected to the drive device; the infrared laser (5), the camera (6) and the drive device are electrically connected to the control center. The infrared laser (5) and the camera (6) collect the plane information of the steel bars and transmit it to the control center. The control center controls the opening and closing of the drive device. The fabric laying machine also includes two auxiliary telescopic arms (7) arranged symmetrically with the main telescopic arm (3) as the axis of symmetry. One end of the auxiliary telescopic arm (7) is connected to the central shaft (1), and the other end is equipped with an infrared laser (5). The auxiliary telescopic arm (7) has the same length as the main telescopic arm (3). The fabric preparation method specifically includes the following steps: Step S1: The drive device drives the central shaft (1) to rotate in the first direction, and the camera (6) and infrared laser (5) collect the current steel bar plane information and transmit it to the control center. Step S2: The control center calculates the positional relationship between the current rebar plane and the concrete placing machine based on the collected information; Step S2 specifically includes the following steps: Step S201: The control center processes the current rebar plane image to obtain a rebar distribution image; Step S202: The control center calculates the positional relationship between the current rebar plane and the concrete placing machine based on the rebar distribution image and the angle through which the infrared laser (5) rotates; Step S202 specifically includes the following steps: Step S2021: Based on the rebar distribution image, obtain the straight line where the rebar is located as detected by the infrared laser (5). Rigid feed tube (4) axis The axis of the field of view of the camera (6) ; Step S2022: Based on the plane geometry, solve for the position of the central axis (1) in the plane of the reinforcing bar, and then obtain the radius of the reinforcing bar in the plane. ; Step S2023, according to The relationship between the fabric radius R of the fabric placing machine and the fabric radius R is used to obtain the dimensional correction coefficient. This allows us to obtain the positional relationship between the steel bar plane and the concrete placing machine. Step S3: The control center calculates the material feeding point based on the positional relationship, and controls the drive device to drive the central shaft (1), main telescopic arm (3), and rigid feeding pipe (4) to feed material at the material feeding point; Step S3 is as follows: Obtain the path trajectory curve of the rigid feed tube (4) center in the current rebar plane after rotating along the first direction, and then obtain the intersection point of the trajectory curve and the contour; the two intersection points on the path trajectory curve closest to the current position are known. , ,get Corresponding central angle Next material feeding point location lie in Midpoint, current position to The required angle of rotation is The drive unit drives the central shaft (1) and the rigid feeding tube (4) to feed materials, completing a single feeding operation and recording the rotation angle of each feeding process. Set the unit feed rate m Single feeding volume ; The angle through which the central axis (1) rotates from its current position to the point where the infrared laser (5) detects the reinforcing bar; Step S4: Determine whether the central axis (1) has rotated one revolution. If yes, proceed to step S5; otherwise, return to step S1. Step S5: Determine whether all material feeding has been completed. If yes, stop the material feeder; otherwise, change the extension length of the main telescopic arm (3) and return to step S1.

2. The fabric application method according to claim 1, characterized in that, The axis of the rigid feed tube (4) coincides with the axis of the field of view of the camera (6).

3. The fabric application method according to claim 1, characterized in that, Step S1 specifically includes the following steps: Step S101: The camera (6) acquires the current planar image of the reinforcing bars and transmits it to the control center; Step S102: Record the current initial position, rotate the central axis (1), stop rotating when the infrared laser (5) detects the steel bar, and record the angle through which the central axis (1) rotates.

4. The fabric application method according to claim 1, characterized in that, Step S201 specifically includes the following steps: Step S2011: Based on the relative height difference between the bottom of the camera (6) and the rigid cutting tube (4) and the focal length of the camera (6), obtain the ratio k of the distance on the bottom position image of the rigid cutting tube (4) on the steel bar plane image to the actual distance; Step S2012: Based on the Canny edge detection algorithm, extract the outline of the reinforcing bars to obtain the reinforcing bar distribution image.

5. The fabric application method according to claim 1, characterized in that, Step S3 specifically includes the following steps: Step S301: Based on the current positional relationship between the steel bar plane and the concrete placing machine, fix the length of the main telescopic arm (3) and make the trajectory of the rigid material feeding pipe (4) in the current steel bar plane after rotating around the central axis (1) in the first direction; Step S302: Extract the intersection points of the reinforcing bars and the trajectory within the current reinforcing bar plane; Step S303: The midpoint of the two nearest adjacent intersections of the rigid feed pipe (4) in the first direction is the feeding point. The control center calculates the angle through which the central axis (1) rotates to reach the feeding point. In step S304, the drive device drives the central shaft (1) and the rigid feed tube (4) to feed materials.

6. The fabric application method according to claim 5, characterized in that, In step S304, the amount M of material fed to each feeding point is: ; in, The total angle rotated through the central axis (1) m represents the unit feed rate; Let the central axis (1) rotate from its current position to the angle through which the infrared laser (5) detects the rebar; define the position of the central axis (1) when the infrared laser (5) detects the rebar as the first position. The angle that the central axis (1) rotates from the first position to the feeding point.

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