Concrete modular building hoisting precision docking device based on visual positioning

Abstract

The application relates to the technical field of building hoisting, and particularly relates to a concrete modular building hoisting precise butt joint device based on visual positioning, which comprises a main hanger, mounting plates, binocular cameras and a rollable lens protection assembly. The main hanger is provided with a rectangular frame, the two sides of the rectangular frame are respectively provided with the mounting plates, each mounting plate is respectively provided with a camera mounting box, and the binocular cameras are installed in the camera mounting boxes. The rollable lens protection assembly comprises upper and lower mounting boxes and an optical-grade polycarbonate film. The upper and lower mounting boxes are respectively fixed to the upper and lower ends of the camera mounting box. A supply winding drum is installed in the upper mounting box, a winding drum is installed in the lower mounting box, one end of the optical-grade polycarbonate film is wound on the supply winding drum, the other end of the optical-grade polycarbonate film is wound on the winding drum, and the optical-grade polycarbonate film covers the front of the binocular camera lens. The application can quickly replace the contaminated film section, does not need to climb, the replacement process does not interrupt the hoisting operation, and the hoisting construction work efficiency and safety are improved.

Description

Technical Field

[0001] This invention relates to the field of building hoisting technology, specifically a visual positioning-based precision docking device for hoisting modular concrete buildings. Background Technology

[0002] With the rapid development of industrialized construction, modular concrete buildings have been widely used in residential buildings, hospitals, schools, and other fields due to their advantages such as fast construction speed, controllable quality, and environmental friendliness. Hoisting and docking is the core process in the construction of modular concrete buildings, and its accuracy and efficiency directly affect the project quality and schedule.

[0003] In recent years, the technology of precise hoisting and docking based on vision positioning has developed rapidly, gradually replacing the traditional operation method of rough alignment adjustment relying on manual crowbars. This technology sets visual targets on the hoisting module and the installed module, uses a binocular camera to collect target images, and combines target feature extraction algorithms and PnP spatial pose calculation algorithms to calculate the three-dimensional spatial deviation between the upper and lower modules in real time. It then drives the horizontal fine-tuning actuator to complete precise positioning, realizing a fundamental shift in the hoisting and docking process from "human experience-oriented" to "data-driven", significantly improving docking accuracy and operational safety.

[0004] However, in the actual application of this type of vision-based hoisting precision docking device on concrete construction sites, there is a fatal flaw that has long remained unresolved: due to the extremely harsh environment of modular concrete construction sites, there are multiple complex working conditions such as continuous high-concentration alkaline concrete dust, large amounts of cement slurry splashing during concrete pouring and module joint treatment, and rainwater intrusion under open-air conditions. These pollutants will quickly adhere to, accumulate, and contaminate the surface of the binocular camera lens. Actual engineering statistics show that under continuous construction conditions, the camera lens surface is usually severely contaminated within 2 to 3 hours, resulting in a sharp drop in the visual target image recognition rate and a serious deviation in pose calculation accuracy from the normal range, which in turn causes the entire hoisting docking system to fail and make it impossible to continue to complete the precision docking operation.

[0005] To address the above problems, the existing technologies mainly employ the following solutions: Firstly, a single transparent protective film is installed in front of the camera lens. When the protective film is contaminated, it is necessary to climb up and manually remove the old film and replace it with a new one. Although this method can play a certain role in lens protection, the replacement process involves multiple steps such as removing the old protective film, aligning and installing the new protective film, and tightening the fasteners. The overall operation takes a long time and the ongoing hoisting operation must be suspended, which seriously disrupts the continuous operation rhythm of modular hoisting construction. Secondly, the maintenance method of manually wiping the lens surface regularly is adopted. However, since the camera is installed at a high altitude under the gantry, each maintenance requires operators to use climbing equipment to work at height. This not only poses a great risk to personal safety, but also has a high maintenance frequency and high labor costs. During rainy weather or peak concrete pouring periods, the lens contamination speed increases dramatically, and the maintenance frequency can even increase to once per hour, which greatly restricts the overall efficiency of hoisting construction. Third, a few solutions attempted to use airflow purging devices to clean the lens surface, but in high humidity environments and under conditions of cement slurry splashing, airflow purging could not effectively remove the adhering slurry contaminants, and the cleaning effect was extremely limited.

[0006] Therefore, there is an urgent need in this field for a precise docking device that can achieve long-term automatic protection of the lens in harsh concrete construction environments, without the need for manual intervention at height and without interrupting the hoisting operation. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide a visual positioning-based precision docking device for concrete modular building hoisting. This device can effectively solve the problem that existing precision docking devices are prone to visual positioning failure due to dust and cement slurry contamination of camera lenses in concrete construction environments. While ensuring the long-term stable operation of the visual positioning system, it significantly improves the overall operational efficiency and safety of hoisting construction.

[0008] The technical solution adopted by this invention to solve its technical problem is: A visual positioning-based concrete modular building hoisting precision docking device includes a main hanger, mounting plates, binocular cameras, and retractable lens protection components. A rectangular frame is set below the main hanger, and mounting plates are set on both sides of the lower end of the rectangular frame. A camera mounting box is set on the inner side of each mounting plate, and the binocular camera is installed in the camera mounting box. The retractable lens protection assembly includes an upper mounting box, a lower mounting box, and an optical-grade polycarbonate film. The upper and lower mounting boxes are respectively sealed and fixed to the upper and lower ends of the camera mounting box. The feed drum is rotatably installed inside the upper mounting box, and the take-up drum is rotatably installed inside the lower mounting box. One end of the optical-grade polycarbonate film is wound onto the feed drum, and the other end is wound onto the take-up drum. The optical-grade polycarbonate film covers the front of the binocular camera lens.

[0009] Compared with the prior art, the beneficial effects of the present invention are: This invention uses a miniature DC geared motor to drive the feed drum and take-up drum, and in conjunction with a photoelectric positioning sensor, it precisely controls the film rolling length. It can automatically complete the replacement of contaminated film within 1 to 2 seconds, eliminating the need for manual climbing and ensuring that the replacement process does not interrupt the hoisting operation. While ensuring the long-term stable operation of the visual positioning system, it significantly improves the overall work efficiency and safety of hoisting construction.

[0010] As a preferred embodiment, a further technical solution of the present invention is: Preferably, the front end of the camera mounting box is provided with a square plate, and a round hole is provided on the square plate, which corresponds to the position of the lens of the binocular camera; a through groove is also provided on the square plate for the optical grade polycarbonate film to pass through.

[0011] Preferably, the side of the optical-grade polycarbonate film facing away from the binocular camera lens is coated with an alkali-resistant dual-hydrophobic nano-ceramic coating.

[0012] Preferably, a miniature DC geared motor is fixedly installed on the upper mounting box and the lower mounting box respectively, and the output shaft of the miniature DC geared motor is connected to the feed drum and the take-up drum respectively.

[0013] Preferably, at least one micro DC geared motor is equipped with a photoelectric positioning sensor at its output end for controlling the rolling length of the optical-grade polycarbonate film.

[0014] Preferably, a control box is provided at one end of the mounting plate, and a PLC control panel is provided inside the control box. Each micro DC geared motor and photoelectric positioning sensor is electrically connected to the PLC control panel.

[0015] Preferably, the thickness of the optical grade polycarbonate film is 0.15 mm.

[0016] Preferably, the dimensions of the optical-grade polycarbonate film are adapted to the slot dimensions of the through groove. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the overall left-side structure of the present invention; Figure 3 This is a schematic diagram of the camera mounting box structure of the present invention; Figure 4This is a schematic diagram of the structure of the miniature DC geared motor of the present invention; Figure 5 This is a schematic diagram of the retractable lens protection assembly of the present invention; Figure 6 This is a schematic diagram of the square plate structure of the present invention; Explanation of reference numerals in the attached drawings: 1. Main hanger; 2. Mounting plate; 3. Control box; 4. Retractable lens protection assembly; 401. Upper mounting box; 402. Lower mounting box; 403. Square plate; 404. Optical grade polycarbonate film; 405. Feed drum; 406. Take-up drum; 407. Through slot; 408. Round hole; 5. Rectangular frame; 6. Camera mounting box; 7. Miniature DC geared motor. Detailed Implementation

[0019] The present invention will be further illustrated below with reference to specific embodiments. The purpose of this illustration is solely to provide a better understanding of the invention. Therefore, the examples given do not limit the scope of protection of the present invention.

[0020] like Figures 1 to 6 As shown, a visual positioning-based concrete modular building hoisting precision docking device consists of a main hanger 1, a mounting plate 2, a binocular camera, and a retractable lens protection assembly 4.

[0021] The main hanger 1 is connected to an X and Y horizontal translation stage below. The X and Y horizontal translation stages are existing technology; for example, they can be composed of mutually perpendicular X-axis linear guides and Y-axis linear guides. A rectangular frame 5 is installed at the bottom of the horizontal translation stage. The rectangular frame 5 can be moved horizontally in two dimensions by means of the X and Y horizontal translation stages.

[0022] Mounting plates 2 are provided on both sides of the lower end of the rectangular frame 5, and a camera mounting box 6 is provided on the inner side of each mounting plate 2.

[0023] The binocular camera is installed inside the camera mounting box 6. During use, a target feature detection module is fixedly installed inside the camera mounting box 6. The target feature detection module is electrically connected to the image output terminal of the binocular camera, and the signal output terminal of the target feature detection module is electrically connected to the PLC control panel to detect the target recognition rate in real time and output a film replacement trigger signal. The above content is existing technology, and the specific principle will not be elaborated here.

[0024] The retractable lens protection assembly 4 consists of an upper mounting box 401, a lower mounting box 402, a square plate 403, and an optical-grade polycarbonate film 404. The upper mounting box 401 and the lower mounting box 402 are made of stainless steel. The upper mounting box 401 and the lower mounting box 402 are respectively sealed and fixed to the upper and lower ends of the camera mounting box 6. The feed drum 405 is rotatably installed inside the upper mounting box 401, and the take-up drum 406 is rotatably installed inside the lower mounting box 402. A miniature DC geared motor 7 is fixedly installed on the upper mounting box 401 and the lower mounting box 402, and the output end of the miniature DC geared motor 7 is connected to the feed drum 405 and the take-up drum 406 respectively.

[0025] One end of the optical-grade polycarbonate film 404 is wound onto the feed spool 405, and the other end is wound onto the take-up spool 406. The optical-grade polycarbonate film 405 covers the front of the binocular camera lens.

[0026] The square plate 403 is fixedly installed on the front end of the camera mounting box 6, and the two ends of the square plate 403 are respectively fixedly connected to the upper mounting box 401 and the lower mounting box 402.

[0027] A circular hole 408 is provided on the square plate 403, and the position of the circular hole 408 corresponds to the position of the binocular camera lens. A through groove 407 is vertically provided on the side of the square plate 403 near the binocular camera lens. The outer dimensions of the optical grade polycarbonate film 404 are adapted to the groove size of the through groove 407 to ensure that the optical grade polycarbonate film 404 can be rolled smoothly without jamming or deviation, so that the optical grade polycarbonate film 404 is attached to the lens.

[0028] In this embodiment, the optical-grade polycarbonate film 404 is selected with a thickness of 0.15mm. This ensures high light transmittance and does not affect the imaging accuracy of the binocular camera, while also having sufficient impact resistance and wear resistance to resist the scratches of concrete particles.

[0029] The optical-grade polycarbonate film 404 has an alkali-resistant dual-repellent nano-ceramic coating sprayed on the side facing away from the binocular camera lens. When concrete dust or cement slurry splashes onto the outer surface of the film, the dual-repellent coating exhibits low surface energy properties, making it difficult for pollutants to adhere or roll off on their own, effectively delaying film contamination. The side close to the binocular camera lens is not coated, maintaining the original high light transmittance and low haze of the optical-grade polycarbonate, avoiding the slight scattering effect that the coating may have on the imaging light path, and maximizing the target recognition accuracy of the binocular camera.

[0030] At least one miniature DC geared motor 7 has a photoelectric positioning sensor at its output end, which is used to control the rolling length of the optical-grade polycarbonate film 404. In this embodiment, a photoelectric positioning sensor can be set at the output end of one of the miniature DC geared motors 7 to control the rolling length of the optical-grade polycarbonate film 404.

[0031] A control box 3 is fixedly installed on one end of the mounting plate 2. The control box 3 contains a PLC control panel. Each micro DC geared motor 7, photoelectric positioning sensor, and X and Y horizontal translation stage is electrically connected to the PLC control panel.

[0032] Based on the above structure, the working principle of this device during use is as follows: Before hoisting operations begin, the main hoist 1 should be rigidly connected to the tower crane hook to complete the overall hoisting and fixing of the device. Subsequently, visual positioning targets of preset specifications were affixed to the four corners of the mating surfaces of the upper precast concrete module to be hoisted and the lower installed module. The initial parameter calibration of the binocular camera and the system self-test were completed through the PLC control panel in the control box 3 to ensure that all electrical components were operating normally. During operation, the tower crane first roughly lifts the upper precast concrete module to directly above the target docking position, completing the manual-assisted rough positioning. At this time, the binocular cameras installed in the camera mounting boxes 6 on both sides of the lower end of the rectangular frame 5 begin to collect target images of the docking surface of the upper and lower modules in real time, and transmit the image data to the PLC control panel for processing. The controller calculates the translational deviation, horizontal rotation deviation, and docking surface tilt deviation between the upper and lower modules in the X and Y horizontal directions through the subpixel-level target center extraction algorithm and the PnP pose calculation algorithm. The deviation signals are converted into control commands and sent to the X and Y horizontal translation stage to drive the rectangular frame 5 and the precast modules suspended below to perform precise fine-tuning in the horizontal direction, preparing for the subsequent precise placement. Throughout the entire hoisting and docking process, the retractable lens protection assembly 4 provides continuous all-weather protection for the binocular camera lens. The upper mounting box 401 and the lower mounting box 402 are sealed and fixed to the upper and lower ends of the camera mounting box 6, forming an IP67-level protection space, which effectively prevents external concrete dust, cement slurry, and rainwater from entering the mounting box and contaminating the supply drum 405, take-up drum 406, and transmission components. Optical grade polycarbonate film 404 is drawn out from feed spool 405, passes through through slot 407 at the upper end of square plate 403 and is wound onto take-up spool 406, flatly covering square plate 403 and in front of binocular camera lens, completely physically isolating binocular camera lens from harsh external environment, and preventing contaminants from directly contacting lens surface. When the target recognition rate drops below 85%, the system automatically determines that the current film segment has exceeded the contamination standard and then triggers the automatic replacement program. The PLC control panel sends drive signals to two miniature DC geared motors 7 synchronously. The two miniature DC geared motors 7 drive the feed drum 405 and the take-up drum 406 to rotate synchronously at the same speed through the coupling. The feed drum 405 releases the clean film segment at a uniform speed, and the take-up drum 406 synchronously and neatly winds up the contaminated film segment. The photoelectric positioning sensor installed at the output of the miniature DC geared motor 7 detects the number of rotations of the motor and sends a feedback signal to the PLC control panel to determine the precise length of movement of the optical-grade polycarbonate film 404. When the clean film segment moves precisely to the position where it is completely aligned with the binocular camera lens, the PLC control panel immediately controls the motor to stop rotating, completing one automatic film replacement.

[0033] The entire replacement process takes only 1 to 2 seconds and is completed automatically during the intervals of hoisting operations. There is no need to stop the hoisting construction or for operators to work at heights. This solves the problem of frequent maintenance of binocular camera lenses and realizes unmanned and automated lens protection. While ensuring visual positioning accuracy, it significantly improves the continuity of hoisting operations and overall construction efficiency.

[0034] The above description is merely a preferred embodiment of the present invention and does not limit the scope of the present invention. All equivalent changes made based on the description and drawings of the present invention are included within the scope of the present invention.

Claims

1. A vision-based positioning-based precision docking device for hoisting modular concrete buildings, characterized in that: It includes a main hanger, mounting plates, a binocular camera, and a retractable lens protection assembly. A rectangular frame is set below the main hanger, and mounting plates are set on both sides of the lower end of the rectangular frame. A camera mounting box is set on the inner side of each mounting plate, and the binocular camera is installed in the camera mounting box. The retractable lens protection assembly includes an upper mounting box, a lower mounting box, and an optical-grade polycarbonate film. The upper and lower mounting boxes are respectively sealed and fixed to the upper and lower ends of the camera mounting box. The feed drum is rotatably installed inside the upper mounting box, and the take-up drum is rotatably installed inside the lower mounting box. One end of the optical-grade polycarbonate film is wound onto the feed drum, and the other end is wound onto the take-up drum. The optical-grade polycarbonate film covers the front of the binocular camera lens.

2. The visual positioning-based concrete modular building hoisting and precision docking device according to claim 1, characterized in that: The front end of the camera mounting box is provided with a square plate, and a round hole is opened on the square plate, which corresponds to the position of the lens of the binocular camera; a through groove is also opened on the square plate for the optical grade polycarbonate film to pass through.

3. The visual positioning-based concrete modular building hoisting and precision docking device according to claim 1, characterized in that: The side of the optical-grade polycarbonate film facing away from the binocular camera lens is coated with an alkali-resistant dual-hydrophobic nano-ceramic coating.

4. The visual positioning-based concrete modular building hoisting and precision docking device according to claim 1, characterized in that: Miniature DC geared motors are fixedly installed on the upper and lower mounting boxes, and the output shafts of the miniature DC geared motors are respectively connected to the feed drum and the take-up drum.

5. The visual positioning-based concrete modular building hoisting precision docking device according to claim 4, characterized in that: At least one miniature DC geared motor is equipped with a photoelectric positioning sensor at its output end for controlling the rolling length of the optical-grade polycarbonate film.

6. The visual positioning-based concrete modular building hoisting precision docking device according to claim 5, characterized in that: A control box is located at one end of the mounting plate. Inside the control box is a PLC control panel, and each miniature DC geared motor and photoelectric positioning sensor is electrically connected to the PLC control panel.

7. The visual positioning-based concrete modular building hoisting precision docking device according to claim 1, characterized in that: The thickness of the optical grade polycarbonate film is 0.15 mm.

8. The visual positioning-based concrete modular building hoisting precision docking device according to claim 2, characterized in that: The dimensions of the optical-grade polycarbonate film are matched with the slot dimensions of the through groove.

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