3D visual guidance steel box girder pushing and positioning method based on Beidou positioning

Abstract

The invention discloses a 3D visual guidance steel box girder pushing and position adjusting method based on Beidou positioning. The method comprises the steps that a Beidou positioning device and an inclinometer are installed at a positioning datum point and a horizontal datum point of a steel box girder respectively; feature identifiers are installed on the box girder segments, and visual devices are correspondingly installed on the outer sides of the box girder segments and are used for monitoring three-dimensional displacement of the feature identifiers in the pushing process in real time; monitoring data of the Beidou positioning device, the inclinometer and the visual device are collected in real time, a dynamic three-dimensional model of the steel box girder is established, and the pushing posture and the pushing stroke of the steel box girder are adjusted on the basis of the dynamic three-dimensional model till the current box girder section reaches the designed mileage. According to the method, the dynamic characteristics of the steel box girder are perfected by taking the Beidou positioning data as the reference and utilizing the visual monitoring data and the inclination angle monitoring data, and the steel box girder pushing dynamic three-dimensional model is established, so that the pushing posture and the pushing stroke of the steel box girder can be automatically and accurately adjusted in the pushing process, and the efficiency and the safety of pushing construction are ensured.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge construction, and more specifically to a method for pushing and adjusting a steel box girder under 3D vision guidance based on Beidou positioning. Background Art

[0002] During the box girder jacking process, visual monitoring methods based on manual or equipment are usually used to judge the current jacking construction progress and jacking error and adjust the box girder. This method requires the arrangement of static and relatively stable monitoring reference points on the outside of the box girder. However, when faced with complex construction conditions and harsh construction conditions, the locations where monitoring reference points can be arranged are limited, and visual monitoring equipment cannot be installed on a large scale. The box girder displacement data that can be collected are relatively small and their accuracy cannot be guaranteed. If additional temporary supports are added to achieve full coverage of monitoring points, although the adequacy of monitoring data is guaranteed, the arrangement of visual monitoring equipment not only requires a lot of manpower and material resources, greatly increases construction time and cost, but also the classification, processing, screening and calculation of a large amount of monitoring data are relatively complex and cumbersome, which can easily affect the timeliness, authenticity and reliability of the final jacking data. In addition, manual visual observation methods also have the same limitations. When monitoring personnel observe the jacking status and position, they cannot convert them into effective control instructions in real time to control the jacking equipment, and frequent adjustments can easily affect the efficiency of jacking construction. The jacking situation judged manually has subjective factors and its accuracy cannot be guaranteed. This close-range manual monitoring method not only increases labor costs but also has greater safety risks.

[0003] To solve the above problems, it is necessary to design a 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning, so as to improve the accuracy of box girder jacking while ensuring the efficiency and safety of jacking construction. Summary of the invention

[0004] The purpose of the present invention is to provide a 3D vision-guided steel box girder jacking adjustment method based on Beidou positioning. Taking Beidou positioning data as a benchmark, visual monitoring data and inclination monitoring data are used to supplement and improve the dynamic characteristics of the steel box girder, and a dynamic three-dimensional model of the steel box girder jacking is established. The method can realize automatic and precise adjustment of the steel box girder jacking posture and jacking stroke during the jacking process, thereby ensuring the efficiency and safety of the jacking construction.

[0005] In order to achieve these purposes and other advantages according to the present invention, a 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning is provided, comprising: S1. Divide the steel box girder to be pushed into multiple box girder segments. After the pushing equipment and the steel box girder are in place, install the Beidou positioning device and the inclinometer at the positioning reference point and the horizontal reference point of the steel box girder respectively, and use the Beidou positioning technology to calibrate the position of the steel box girder and the installation position of the characteristic mark on each box girder segment; S2. Install a characteristic mark at the marked position of the first box girder segment, and install a corresponding visual device on the fixed structure outside the box girder segment, which is configured to monitor the displacement of the characteristic mark in three directions of length, width and height of the bridge in real time during the jacking process; S3, according to the design requirements, the current box girder segment is pushed forward, the monitoring data of the Beidou positioning device, the inclinometer and the visual device are collected in real time, and the dynamic three-dimensional model of the steel box girder in the pushing process is established in combination with the design parameters of the steel box girder, and the pushing posture and pushing stroke of the steel box girder are adjusted based on this, until the current box girder segment reaches the designed pushing mileage; S4, moving the characteristic mark to the calibration position of the next box girder segment, and repeating the step of S3 until the jacking construction of all the box girder segments is completed.

[0006] Preferably, in the 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning, in S1, the positioning reference point is set at the middle of the guide beam of the steel box girder, and the horizontal reference point is set at the outer end of the guide beam of the steel box girder.

[0007] Preferably, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, in S2, the feature identification includes two groups of target devices, which are symmetrically arranged on both sides of the box girder segment, and any one group of target devices is arranged on the corresponding steel box girder side wall. The one group of target devices includes multiple target devices, which are staggered in the length direction and height direction of the bridge, and any one target device is arranged parallel to the corresponding steel box girder side wall and a target point is provided at the center position; the visual device includes two 3D industrial cameras, which are arranged on both sides of the steel box girder corresponding to the two groups of target devices, and the detection direction of any one of the 3D industrial cameras is facing the side wall of the steel box girder.

[0008] Preferably, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, the target device and the 3D industrial camera are both installed through an adjusting bracket, and the adjusting bracket includes a magnetic base, which is equipped with a switch for controlling the magnetic state; a support rod, which is fixed on the magnetic base; an adjusting rod, one end of which is slidably connected to the support rod along the length direction through a positioning mechanism, and the other end is used to install the target device or the 3D industrial camera.

[0009] Preferably, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, a protective cover is provided on the outside of the 3D industrial camera, which includes a base plate, which is configured to support and fix the 3D industrial camera; an outer shell, which is fixed to the base plate and covers the outside of the 3D industrial camera, and the outer shell is provided with a through hole corresponding to the lens of the 3D industrial camera and for the visual light source to pass through.

[0010] Preferably, in the 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning, in S3, the designed jacking mileage of each box girder segment is determined according to the design parameters of the visual device and the jacking equipment, and the designed jacking mileage of any box girder segment corresponds to one or more jacking strokes of the jacking equipment.

[0011] Preferably, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, in S3, the method for adjusting the pushing posture of the steel box girder based on the dynamic three-dimensional model of the steel box girder includes: comparing the steel box girder posture data displayed in real time by the dynamic three-dimensional model with the steel box girder posture data in the initial calibration state; when the real-time steel box girder posture deviation exceeds the set deflection control threshold, pausing the pushing, and adjusting the lifting height of each point of the pushing equipment; and continuing the original pushing action after the steel box girder posture is re-leveled; the steel box girder posture data includes the deflection angle of the center line of the steel box girder along the length direction relative to the horizontal plane, and the deflection angle of the mid-perpendicular line of the steel box girder relative to the vertical plane.

[0012] Preferably, in the 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning, laser ranging devices are respectively installed at both ends of the jacking equipment, which are fixed on the pier and used to measure the jacking height of the jacking equipment during the jacking process; In S3, the method for adjusting the jacking posture of the steel box girder based on the dynamic three-dimensional model of the steel box girder also includes: real-time acquisition of measurement data of the laser ranging device, and in the jacking state, when the deviation between the measurement data of any laser ranging device and the preset jacking height value or the difference between the measurement data of the two laser ranging devices exceeds the set height difference control threshold, suspending the jacking, and adjusting the jacking height of each point of the jacking equipment, and continuing the original jacking action after the posture of the steel box girder is re-leveled.

[0013] Preferably, the method for jacking and adjusting the steel box girder based on Beidou positioning and 3D vision guidance, and the method for adjusting the jacking stroke of the steel box girder based on the dynamic three-dimensional model of the steel box girder include: S31, dividing the designed jacking mileage of the current box girder segment into a plurality of jacking sections according to a single jacking stroke of the jacking equipment, and presetting the three-dimensional coordinates of the characteristic mark in each jacking section; S32, after a jacking operation of the jacking device is completed, calculating the deviation value of the current jacking mileage according to the difference between the actual coordinates of the feature mark on the dynamic three-dimensional model and the preset coordinates in S31; S33, correcting the pushing stroke of the pushing device in the next pushing action by using the deviation value calculated in S32, and controlling the pushing device to perform the next pushing action according to the corrected stroke value; S34, repeating the steps of S32-S33 until all the pushing operations in the pushing sections are completed.

[0014] The present invention has at least the following beneficial effects: 1. The present invention uses Beidou positioning data as a benchmark, visual monitoring data and inclination monitoring data to supplement and improve the dynamic characteristics of the steel box girder, and establishes a dynamic three-dimensional model of the steel box girder jacking, which can realize automatic and accurate adjustment of the jacking posture and jacking stroke of the steel box girder during the jacking process, guide the execution of the jacking action according to a variety of positioning and monitoring data, and improve the accuracy of the box girder jacking in place while ensuring the efficiency and safety of the jacking construction; 2. The present invention adopts Beidou positioning device, inclinometer and visual device, and feature identification to realize full-range monitoring of the jacking status of steel box girder, and realizes the construction of dynamic three-dimensional model through the combination of multiple monitoring data. Under the condition of ensuring continuous and sufficient monitoring data, the number of points used for monitoring is reduced as much as possible, the installation steps of monitoring equipment are simplified, and the installation difficulty is reduced, thereby effectively reducing the equipment and labor costs in the jacking construction of steel box girder and further improving the jacking construction efficiency.

[0015] Other advantages, objectives and features of the present invention will be embodied in part through the following description, and in part will be understood by those skilled in the art through study and practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a schematic diagram of the plan structure of a 3D vision-guided steel box girder jacking monitoring and positioning system based on Beidou positioning according to an embodiment of the present invention; Figure 2 It is a schematic diagram of the structure of the connection between the target device and the adjustment bracket in the above embodiment; Figure 3 is a schematic structural diagram of the housing described in the above embodiment; Figure 4 4 is a control structure diagram of the control system described in the above embodiment.

[0017] Description of reference numerals: 1. Steel box girder; 2. Guide beam; 3. Pushing equipment; 4. Lifting mechanism; 5. Target device; 6. 3D industrial camera; 7. Beidou positioning device; 8. Inclinometer; 9. Magnetic base; 10. Support rod; 11. Adjustment rod; 12. Outer shell; 13. Through hole; 14. Laser ranging device. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with the accompanying drawings so that those skilled in the art can implement the invention with reference to the description.

[0019] It should be noted that the experimental methods described in the following embodiments are conventional methods unless otherwise specified, and the reagents and materials are commercially available unless otherwise specified; in the description of the present invention, the terms "lateral", "longitudinal", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0020] like Figure 1-4 As shown, a 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning includes: S1. Divide the steel box girder 1 to be pushed into multiple box girder segments. After the pushing equipment 3 and the steel box girder 1 are in place, install the Beidou positioning device 7 and the inclinometer 8 at the positioning reference point and the horizontal reference point of the steel box girder 1 respectively, and use the Beidou positioning technology to calibrate the position of the steel box girder and the installation position of the characteristic mark on each box girder segment; S2. Install a feature mark at the calibrated position of the first box girder segment, and install a corresponding visual device on the fixed structure outside the box girder segment, which is configured to monitor in real time the displacement of the feature mark in the three directions of length, width and height of the bridge during the jacking process; the displacement of the feature mark in the three directions of length, width and height of the bridge can be used as the displacement of the corresponding feature point on the steel box girder (the feature mark installation point calibrated on the current box girder node) in the three directions of length, width and height; S3, according to the design requirements, the current box girder segment is pushed forward, the monitoring data of the Beidou positioning device 7, the inclinometer 8 and the visual device are collected in real time, and the dynamic three-dimensional model of the steel box girder 1 in the pushing process is established in combination with the design parameters of the steel box girder 1, and the pushing posture and pushing stroke of the steel box girder are adjusted based on this, until the current box girder segment reaches the designed pushing mileage; Among them, when establishing the dynamic three-dimensional model of the steel box girder, the basic framework of the model is established based on the coordinate changes of the steel box girder design structure and the positioning reference points fed back by the Beidou positioning device. The coordinate changes of the feature identifiers collected by the visual device are used to improve and optimize (correct) the coordinate data of the corresponding feature identifier installation points on the model. The inclination data of the steel box girder in different directions collected by the inclinometer are then used to improve and optimize (correct) the overall posture changes of the model, thereby obtaining a dynamic three-dimensional model of the steel box girder.

[0021] S4, moving the characteristic mark to the calibration position of the next box girder segment, and repeating the step of S3 until the jacking construction of all the box girder segments is completed.

[0022] In the above technical solution, a control system is provided, which includes a controller and a display. The monitoring data collected by each monitoring device (Beidou positioning device, inclinometer, visual device) are transmitted to the control system in real time through electrical signals or network signals, and the controller performs data processing, analysis and calculation. The controller is also equipped with a modeling platform (such as 3d Max, etc.) for establishing a dynamic three-dimensional model of the jacking process of the steel box girder based on a variety of monitoring data. The display can display the digital dynamic three-dimensional model and key jacking control parameters (such as real-time jacking mileage and deviation of the steel box girder, lateral displacement of the steel box girder, and inclination angles of the steel box girder in all directions). The controller is also connected to each actuator of the jacking device through electrical signals or network signals, and the working state of the jacking device can be controlled and adjusted according to the value of the above jacking control parameters to control the jacking posture and jacking stroke of the steel box girder during the jacking process, so as to ensure that the steel box girder can be accurately jacked into place according to the designed posture. The display is also equipped with an external input device (such as a keyboard, etc.) and has an input function. Construction personnel can remotely monitor the status of the jacking construction through the data displayed on the display, and send corresponding control instructions to the controller through the external input device via the display, so as to manually assist in guiding the jacking construction and ensure the smooth and safe progress of the jacking construction.

[0023] In S1, before the inclinometer is installed, it is necessary to first use a level meter or other device to measure the horizontality of the steel box girder in the initial state and level it (the horizontality of the steel box girder can be corrected by a leveling steel plate or other structure) to ensure the validity and reliability of the inclination data fed back after the inclinometer is installed. During calibration, if it is found that the position of the steel box girder in the initial state (i.e., the three-dimensional coordinates received by the Beidou positioning device) deviates from the design initial coordinates of the positioning reference point, it is necessary to first correct the initial position of the steel box girder through a jacking device or other auxiliary positioning devices (each direction cylinder, jack, etc.) so that the coordinates of the positioning reference point measured in real time by the Beidou positioning device coincide with its design coordinates; during the steel box girder position correction process, the measurement data of the inclinometer is collected in real time, and the inclination angle of the characteristic plane represented by the horizontal reference point in the front and back, left and right directions is calculated, and the deflection control threshold in each direction is set. When the inclination angle in any direction exceeds the corresponding deflection control threshold, the steel box girder can be re-leveled through the jacking mechanisms of the jacking device.

[0024] In S3, a dynamic three-dimensional model is constructed by combining multiple monitoring data. While ensuring continuous and sufficient monitoring data, the number of monitoring points is reduced as much as possible, the installation steps of the monitoring equipment are simplified, and the installation difficulty is reduced. This effectively reduces the equipment and labor costs in the steel box girder jacking construction and improves the jacking construction efficiency.

[0025] The present invention takes Beidou positioning data as a benchmark, uses visual monitoring data and inclination monitoring data to supplement and improve the dynamic characteristics of the steel box girder, and establishes a dynamic three-dimensional model of the steel box girder jacking. It can realize automatic and precise adjustment of the jacking posture and jacking stroke of the steel box girder during the jacking process, and guides the execution of the jacking action according to a variety of positioning and monitoring data, thereby improving the accuracy of the box girder jacking into place while ensuring the efficiency and safety of the jacking construction.

[0026] In another technical solution, in the method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning, in S1, the positioning reference point is set at the middle of the guide beam 2 of the steel box girder 1, and the horizontal reference point is set at the outer end of the guide beam 2 of the steel box girder 1. The positioning reference point and the horizontal reference point are both located on the center line of the steel box girder along the length direction, so as to obtain more representative positioning and inclination data, and also facilitate the calculation of the theoretical positions of other feature points on the steel box girder.

[0027] The measurement data of the inclinometer 8 and the Beidou positioning device 7 can be transmitted to the control system in real time by wireless transmission. In this embodiment, the inclinometer adopts a wireless inclination sensor, which is installed at the front end of the top surface of the leading beam of the steel box girder, and the Beidou positioning device adopts a high-precision GNSS receiver, which is installed in the middle of the top surface of the leading beam.

[0028] In another technical solution, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, in S2, the feature identification includes two groups of target devices 5, which are symmetrically arranged on both sides of the box girder segment, and any one group of target devices is arranged on the corresponding steel box girder side wall. The one group of target devices includes multiple target devices 5, which are staggered in the length direction and height direction of the bridge, and any one target device is arranged parallel to the corresponding steel box girder side wall and a target point is provided at the center position; the visual device includes two 3D industrial cameras 6, which are arranged on both sides of the steel box girder corresponding to the two groups of target devices 5, and the detection direction of any one of the 3D industrial cameras 6 is facing the side wall of the steel box girder 1.

[0029] In the above technical solution, the 3D industrial camera actually measures the three-dimensional displacement data of multiple target points in a corresponding set of target devices. The 3D industrial camera uses a conventional commercially available model and can achieve three-dimensional ranging through binocular stereo vision or laser triangulation or structured light technology. For example, when a 3D structured light camera is used, it projects light with certain structural characteristics onto the corresponding target device through a near-infrared laser. This light with a certain structure will collect different image phase information due to the depth change of the object being photographed. The change of this structure can be converted into depth information through the built-in computing unit, and then combined with the displacement of the target point along the horizontal longitudinal direction (bridge length direction) and the height direction, the coordinate change information of the corresponding target point in the horizontal transverse direction (bridge width direction) can be calculated. The feature identifier and the visual device are symmetrically arranged on both sides of the box girder, which is convenient for the visual device to measure the corresponding feature identifier position information. At the same time, the setting of the two sets of target devices can represent the dynamic position change of the contour lines on both sides of the box girder. Combined with the coordinate information of the single point (positioning reference point) monitored by the Beidou positioning device, the three-dimensional position information database of the steel box girder under the three-dimensional structure can be obtained. Therefore, under the condition of a limited number of monitoring points, dynamic three-dimensional modeling of steel box girders with high accuracy can be achieved. The positioning reference points, horizontal reference points and feature identifiers are all directly installed on the steel box girder. The visual device only needs to set up one monitoring point on each side of the steel box girder, and a set of fixed structures (such as temporary piers, etc.) for installing the monitoring points are also required. By changing the position of the feature identifier on the steel box girder, 3D visual inspection of the entire length of the steel box girder during jacking can be achieved. There is no need to set up a large number of additional temporary supports, which effectively simplifies the steps of monitoring equipment layout, reduces construction costs, and further improves construction efficiency.

[0030] In another technical solution, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, the target device 5 and the 3D industrial camera 6 are both installed through an adjusting bracket, and the adjusting bracket includes a magnetic base 9, which is equipped with a switch for controlling the magnetic state; a support rod 10, which is fixed on the magnetic base; an adjusting rod 11, one end of which is slidably connected to the support rod 10 along the length direction through a positioning mechanism, and the other end is used to install the target device 5 or the 3D industrial camera 6.

[0031] Among them, the magnetic base 9 is a magnetically adjustable device. When the switch is in the on state, the N or S pole of the magnet in the magnetic base faces the surface of the soft magnetic material, making it have strong magnetism and able to be stably adsorbed on the steel surface; when the switch is in the off state, the middle of the NS pole of the magnet faces the surface of the soft magnetic material. At this time, the soft magnetic material will not be magnetized, and there is almost no magnetic force on the base, so the magnetic base can be easily removed from the steel surface. Therefore, when the target device and the 3D industrial camera are installed, the above-mentioned monitoring equipment can be quickly installed at the specified position according to the set orientation, which is also conducive to the rapid and convenient switching of the target device between different box beam sections. In addition, the adjusting rod 11 and the supporting rod 10 are arranged perpendicular to each other, one end of the positioning mechanism is fixedly mounted on the adjusting rod 11, and the other end is slidably connected to the supporting rod 10, and the position of the positioning mechanism on the supporting rod 10 can be locked by a limiting device such as a bolt. Therefore, after the target device 5 or the 3D industrial camera 6 is adsorbed to the corresponding monitoring point (installation point) through the magnetic base 9, the installation position (mileage, height, etc.) of the target device or the 3D industrial camera can still be fine-tuned by the positioning mechanism, which is conducive to achieving precise alignment of the target device and the corresponding visual device, and ensuring the accuracy and reliability of subsequent visual monitoring data.

[0032] In another technical solution, in the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, a protective cover is provided on the outside of the 3D industrial camera, which includes a base plate, which is configured to support and fix the 3D industrial camera; an outer shell 12, which is fixed on the base plate and covers the outside of the 3D industrial camera, and the outer shell is provided with a through hole 13 corresponding to the lens of the 3D industrial camera and for the visual light source to pass through.

[0033] The 3D industrial camera 6 is first installed on the bottom plate, and then the housing 12 is installed, so that a relatively closed space is formed between the housing 12 and the bottom plate to protect the 3D industrial camera from external interference during operation. Since the 3D industrial camera has a visual light source (generally a laser emitting device), in addition to the lens opening, an additional through hole is required on the housing to allow light from the visual light source to pass through.

[0034] In another technical solution, in the 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning, in S3, the designed jacking mileage of each box girder segment is determined according to the design parameters of the visual device and the jacking equipment 3, and the designed jacking mileage of any box girder segment corresponds to one or more jacking strokes of the jacking equipment 3.

[0035] In the above technical scheme, the jacking action performed by the jacking equipment is actually a cycle of multiple jacking strokes. In any jacking stroke, the jacking mechanism 4 of the jacking equipment 3 first lifts the steel box girder 1 to a set height to separate it from the support seat, and then drives the steel box girder 1 to move forward as a whole through the action of the jacking mechanism. The maximum distance allowed for forward movement is determined by the design parameters of the jacking mechanism (the jacking stroke is selected within this range). After moving forward the set stroke, the jacking mechanism 4 is reset to place the steel box girder 1 back on the original support seat. Thereafter, the jacking mechanism is reset, completing a jacking stroke. Among them, the jacking mechanism 4 can adopt a vertical jacking cylinder, and the jacking mechanism can adopt a horizontal jack. Both the jacking mechanism and the jacking mechanism on the jacking equipment 3 can be arranged in multiples. In this embodiment, if Figure 1 As shown, two groups of jacking mechanisms 4 are arranged at intervals along the length direction of the bridge, and any group of jacking mechanisms includes two jacking mechanisms 4 arranged at intervals along the width direction of the bridge, so that when a bridge posture deviation is detected, the bridge can be re-leveled by different jacking mechanisms.

[0036] The design parameters of the visual device include the distance between the visual device and the steel box girder, the performance parameters of the visual device, etc. The maximum visual range of the visual device in the length direction of the bridge is calculated based on the various parameters, and then the design jacking mileage (distance) of the box girder segment is determined in combination with the design parameters of the jacking equipment (single jacking stroke) to ensure that during the jacking process of the box girder segment, the characteristic mark is always within the field of view of the corresponding visual device, and the design jacking mileage of a box girder segment is an integer multiple of the single jacking stroke of the jacking equipment, which is convenient for controlling the entire jacking process of a single box girder segment.

[0037] The length of the box girder segment and the installation position of the characteristic mark on each box girder segment should be selected according to the following principle: when the previous box girder segment reaches the designed jacking mileage (i.e., when it moves the set distance) under jacking, the installation position of the characteristic mark on the next box girder segment enters the field of view of the corresponding visual device. It is worth noting that before the first box girder segment is jacked, the installation device of its characteristic mark is located within the field of view of the corresponding visual device.

[0038] In another technical solution, the 3D vision-guided steel box girder pushing and positioning method based on Beidou positioning, in S3, the method for adjusting the pushing posture of the steel box girder based on the dynamic three-dimensional model of the steel box girder includes: comparing the steel box girder posture data displayed in real time by the dynamic three-dimensional model with the steel box girder posture data in the initial calibration state; when the real-time steel box girder posture deviation exceeds the set deflection control threshold, suspending the pushing, and adjusting the lifting height of each point of the pushing equipment; and continuing the original pushing action after the steel box girder posture is re-leveled; the steel box girder posture data includes the deflection angle of the center line of the steel box girder along the length direction relative to the horizontal plane, and the deflection angle of the mid-perpendicular line of the steel box girder relative to the vertical plane.

[0039] Among them, the structural design parameters of the steel box girder, the theoretical coordinates (design coordinates) of each characteristic point on the steel box girder during the jacking process, and the monitoring data generated during the jacking process are all stored in the database of the control system. In addition, according to the requirements of construction accuracy control, control thresholds are also preset for each key parameter (steel box girder deflection / inclination angle in each direction, jacking height difference, box girder segment jacking mileage deviation, etc.). After establishing the dynamic three-dimensional model of the steel box girder, the controller automatically analyzes and compares the difference between the real-time posture data of the steel box girder and the posture data of the steel box girder in the initial calibration state through the built-in module. When the deflection angle in a certain direction exceeds the set deflection control threshold, it is judged that the inclination angle of the steel box girder in this direction has exceeded the allowable deviation range. The posture of the steel box girder needs to be corrected according to the specific difference. The steel box girder can be re-leveled through the jacking mechanism at different positions. After the real-time posture data of the steel box girder meets the design requirements, the original jacking action can be continued.

[0040] In another technical solution, the 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning is provided with laser ranging devices 14 installed at both ends of the jacking equipment, which are fixed on the pier and used to measure the jacking height of the jacking equipment during the jacking process; In S3, the method for adjusting the jacking posture of the steel box girder based on the dynamic three-dimensional model of the steel box girder also includes: real-time acquisition of measurement data of the laser ranging device 14, and in the jacking state, when the deviation between the measurement data of any laser ranging device 14 and the preset jacking height value or the difference between the measurement data of the two laser ranging devices 14 exceeds the set height difference control threshold, suspending the jacking, and adjusting the jacking height of each point (each jacking mechanism) of the jacking equipment 3, and continuing the original jacking action after the posture of the steel box girder is re-leveled.

[0041] In the above technical solution, the laser distance measuring device 14 can be a commercially available laser distance measuring device, which is installed at the front and rear ends of the jacking device, that is, the two laser distance measuring devices 14 are respectively located in front and behind the jacking device 3 along the jacking direction. Any laser distance measuring device is fixed on the pier and is located in the same plane as the mounting seat of the jacking device. The laser emission direction of the laser distance measuring device is vertically upward and is set directly opposite to the bottom of the steel box girder. Therefore, the two laser distance measuring devices can respectively measure the actual lifting height at different length positions of the steel box girder located in front and behind the jacking device. The jacking state is the continuous working state from the jacking mechanism of the jacking device to the reset (before the reset action is performed) after the jacking mechanism of the jacking device is lifted into place (the jacking action is completed). By setting up a laser distance measuring device, the posture deviation of the steel box girder caused by the execution error of the jacking device itself (such as the action error of the jacking mechanism, the control synchronization error, etc.) can be judged more intuitively, accurately and quickly, and corrected in time.

[0042] The above-mentioned jacking height difference control based on the laser ranging device and the deflection control based on the dynamic three-dimensional model are carried out simultaneously. When any judgment criterion exceeds the set control threshold value, the jacking action needs to be stopped, the steel box girder needs to be re-leveled and then the original action can be continued to ensure the stability of the steel box girder posture during the jacking process, thereby ensuring the accuracy of the jacking distance control of the steel box girder.

[0043] In another technical solution, the method for jacking and adjusting the steel box girder based on Beidou positioning and 3D vision guidance, and the method for adjusting the jacking stroke of the steel box girder based on the dynamic three-dimensional model of the steel box girder include: S31, dividing the designed jacking mileage of the current box girder segment into a plurality of jacking sections according to a single jacking stroke of the jacking equipment, and presetting the three-dimensional coordinates of the characteristic mark in each jacking section; S32, after a jacking operation of the jacking device is completed, calculating the deviation value of the current jacking mileage according to the difference between the actual coordinates of the feature mark on the dynamic three-dimensional model and the preset coordinates in S31; S33, correcting the pushing stroke of the pushing device in the next pushing action by using the deviation value calculated in S32, and controlling the pushing device to perform the next pushing action according to the corrected stroke value; S34, repeating the steps of S32-S33 until all the pushing operations in the pushing sections are completed.

[0044] In S34, if a jacking mileage deviation still occurs in the last jacking action corresponding to the current box girder segment, after the jacking actions in all jacking segments are completed, first determine whether the mileage difference between the actual coordinates of the feature identifier on the dynamic three-dimensional model and the preset coordinates in S31 exceeds the set mileage deviation threshold. If so, the difference is substituted into the first jacking action of the next box girder segment for correction; if not, the jacking construction of the next box girder segment can be carried out normally.

[0045] In this embodiment, a 3D vision-guided steel box girder jacking and positioning system based on Beidou positioning includes: A Beidou positioning receiver is installed in the middle of the leading guide beam of the steel box girder to be pushed; A wireless inclination sensor is installed at the front end of the front guide beam of the steel box beam to be pushed; Two laser rangefinders, which are located at both ends of the jacking device and installed on the pier; Two sets of target devices are respectively installed on the side walls of the steel box girder to be pushed through adjusting brackets, and each target device includes a target plate with a target point at the center; Two 3D industrial cameras are arranged corresponding to the two groups of target devices, and any one of the 3D industrial cameras is fixed on a temporary pier outside the steel box girder through an adjustable bracket, and a protective cover is arranged outside the 3D industrial camera; The adjustment bracket includes a magnetic base, a support rod and an adjustment rod; Control system, which includes a monitoring host, a controller, and a communication module (including but not limited to a 5G module and a wireless communication module); Among them, the signal of the wireless inclination sensor is received by the wireless receiver and then converted into a network signal and transmitted to the controller and monitoring host. The signal of the Beidou positioning receiver is directly transmitted to the controller. The signals of the laser rangefinder and 3D industrial camera are transmitted to the controller and monitoring host via the network. The various actuators of the jacking equipment also exchange information with the controller and monitoring host through the network connection.

[0046] In actual construction, after the jacking equipment and the steel box girder are in place, the 3D vision-guided box girder jacking and positioning system based on Beidou positioning is installed to a suitable position, and the subsequent jacking and positioning steps are performed according to the technical solution of the present invention.

[0047] Although the embodiments of the present invention have been disclosed as above, they are not limited to the applications listed in the specification and the implementation modes, and they can be fully applied to various fields suitable for the present invention. For those familiar with the art, additional modifications can be easily implemented. Therefore, without departing from the general concept defined by the claims and the scope of equivalents, the present invention is not limited to the specific details and the illustrations shown and described herein.

Claims

1. A 3D vision-guided steel box girder jacking and positioning method based on Beidou positioning, characterized in that: include: S1. Divide the steel box girder to be pushed into multiple box girder segments. After the pushing equipment and the steel box girder are in place, install the Beidou positioning device and the inclinometer at the positioning reference point and the horizontal reference point of the steel box girder respectively, and use the Beidou positioning technology to calibrate the position of the steel box girder and the installation position of the characteristic mark on each box girder segment; S2. Install a characteristic mark at the marked position of the first box girder segment, and install a corresponding visual device on the fixed structure outside the box girder segment, which is configured to monitor the displacement of the characteristic mark in three directions of length, width and height of the bridge in real time during the jacking process; S3, according to the design requirements, the current box girder segment is pushed forward, the monitoring data of the Beidou positioning device, the inclinometer and the visual device are collected in real time, and the dynamic three-dimensional model of the steel box girder in the pushing process is established in combination with the design parameters of the steel box girder, and the pushing posture and pushing stroke of the steel box girder are adjusted based on this, until the current box girder segment reaches the designed pushing mileage; S4, moving the characteristic mark to the calibration position of the next box girder segment, and repeating the step of S3 until the jacking construction of all box girder segments is completed.

2. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 1 is characterized in that: In S1, the positioning reference point is set at the middle of the guide beam of the steel box beam, and the horizontal reference point is set at the outer end of the guide beam of the steel box beam.

3. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 1 is characterized in that: In S2, the feature identification includes two groups of target devices, which are symmetrically arranged on both sides of the box girder segment, and any one group of target devices is arranged on the corresponding side wall of the steel box girder. The one group of target devices includes multiple target devices, which are staggered in the length direction and height direction of the bridge. Any one target device is arranged parallel to the corresponding side wall of the steel box girder and a target point is provided at the center position; the visual device includes two 3D industrial cameras, which are arranged on both sides of the steel box girder corresponding to the two groups of target devices, and the detection direction of any one of the 3D industrial cameras is facing the side wall of the steel box girder.

4. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 3 is characterized in that: The target device and the 3D industrial camera are both installed through an adjustment bracket, which includes a magnetic base, which is equipped with a switch for controlling the magnetic state; a support rod, which is fixed on the magnetic base; an adjustment rod, one end of which is slidably connected to the support rod along the length direction through a positioning mechanism, and the other end is used to install the target device or the 3D industrial camera.

5. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 3 is characterized in that: A protective cover is provided on the outside of the 3D industrial camera, which includes a base plate, which is configured to support and fix the 3D industrial camera; an outer shell, which is fixed to the base plate and covers the outside of the 3D industrial camera, and the outer shell is equipped with a through hole corresponding to the lens of the 3D industrial camera and for the visual light source to pass through.

6. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 1, characterized in that: In S3, the designed jacking mileage of each box girder segment is determined according to the design parameters of the visual device and the jacking equipment, and the designed jacking mileage of any box girder segment corresponds to one or more jacking strokes of the jacking equipment.

7. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 1, characterized in that: In S3, the method for adjusting the jacking posture of the steel box girder based on the dynamic three-dimensional model of the steel box girder includes: comparing the steel box girder posture data displayed in real time by the dynamic three-dimensional model with the steel box girder posture data in the initial calibration state; when the real-time steel box girder posture deviation exceeds the set deflection control threshold, suspending the jacking, and adjusting the jacking height of each point of the jacking equipment; and continuing the original jacking action after the steel box girder posture is re-leveled; the steel box girder posture data includes the deflection angle of the center line of the steel box girder along the length direction relative to the horizontal plane, and the deflection angle of the median perpendicular line of the steel box girder relative to the vertical plane.

8. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 7, characterized in that: Laser distance measuring devices are respectively installed at both ends of the jacking device, which are fixed on the pier and used to measure the lifting height of the jacking device during the jacking process; In S3, the method for adjusting the jacking posture of the steel box girder based on the dynamic three-dimensional model of the steel box girder also includes: real-time acquisition of measurement data of the laser ranging device, and in the jacking state, when the deviation between the measurement data of any laser ranging device and the preset jacking height value or the difference between the measurement data of the two laser ranging devices exceeds the set height difference control threshold, suspending the jacking, and adjusting the jacking height of each point of the jacking equipment, and continuing the original jacking action after the posture of the steel box girder is re-leveled.

9. The method for pushing and adjusting the steel box girder using 3D vision guidance based on Beidou positioning as claimed in claim 1, characterized in that: The method for adjusting the jacking stroke of the steel box girder based on the dynamic three-dimensional model of the steel box girder includes: S31, dividing the designed jacking mileage of the current box girder segment into a plurality of jacking sections according to a single jacking stroke of the jacking equipment, and presetting the three-dimensional coordinates of the characteristic mark in each jacking section; S32, after a jacking operation of the jacking device is completed, calculating the deviation value of the current jacking mileage according to the difference between the actual coordinates of the feature mark on the dynamic three-dimensional model and the preset coordinates in S31; S33, correcting the pushing stroke of the pushing device in the next pushing action by using the deviation value calculated in S32, and controlling the pushing device to perform the next pushing action according to the corrected stroke value; S34, repeating the steps of S32-S33 until all the pushing operations in the pushing sections are completed.

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