BIM and unmanned aerial vehicle based positioning method for air installation of prefabricated bridge components

Abstract

The application relates to a kind of BIM and unmanned aerial vehicle-based prefabricated bridge component aerial installation positioning construction methods, belong to construction assembly technical field, step one: BIM model construction, according to bridge design drawing, establish the three-dimensional BIM model including all bridge components, complete the generation of construction data;Step two: unmanned aerial vehicle system configuration, according to the construction data generated by BIM model, plan the flight path and task of unmanned aerial vehicle;Step three: complete prefabricated bridge component prefabrication and transportation;Step four: unmanned aerial vehicle monitors bridge component according to flight path, ground control center fuses the monitoring data collected by unmanned aerial vehicle and BIM model through data matching and coordinate conversion algorithm, completes monitoring, in this process, ground control center judges the position of unmanned aerial vehicle during hovering process. When the drift value exceeds the threshold value, the ground control center sends a hovering correction instruction to the unmanned aerial vehicle and stops receiving the data of the unmanned aerial vehicle.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of construction assembly, and particularly relates to an assembly type bridge component aerial installation positioning construction method based on BIM and a drone. BACKGROUND

[0002] Under the background of the rapid development of current transportation infrastructure construction, the assembly type bridge has been widely applied in the field of bridge engineering due to the advantages of fast construction speed, easy quality control and small environmental impact.

[0003] During the installation stage of the prefabricated component, the hoisted prefabricated component has certain high-altitude detection risks. The use of traditional manual detection or the erection of a millimeter-level three-dimensional laser scanner for collection is not convenient for the top collection of the prefabricated component and has certain high-altitude hidden dangers, and is not suitable for manual detection. With the increase of height, the collection accuracy of the three-dimensional laser scanner is also reduced, and it is difficult to guarantee the accuracy detection requirements and the integrity of the prefabricated component. Therefore, Chinese patent CN119554967B discloses a large prefabricated component key size detection method, device, electronic equipment and storage medium. The method comprises the following steps: S1, constructing a prefabricated component BIM model based on BIM technology; S2, during the factory processing stage, constructing a millimeter-level point cloud model of the prefabricated component based on the prefabricated component BIM model, a drone and a three-dimensional laser scanner to perform prefabricated component inspection and key size precision detection; and S3, during the installation stage, constructing an overall centimeter-level, prefabricated component millimeter-level construction site large scene real scene three-dimensional model and a BIM+GIS fusion platform to realize automatic detection of key size precision during the installation stage and guarantee the compliance with the acceptance specification requirements. The application improves the large workpiece detection efficiency and detection accuracy by complementary advantages of BIM, drone aerial survey technology and three-dimensional laser scanning technology, and prevents the prefabricated component from being returned to the factory and the low installation positioning accuracy on site.

[0004] However, in the above steps, due to the inherent defects of the drone itself, such as being easily affected by the cumulative path deviation during flight or being easily blown off by the wind, the flight accuracy and coordinate accuracy of the drone cannot be compared with the completely digitally modeled BIM data, and there is a probability that the BIM model coordinate system, the drone itself coordinate system and the gimbal coordinate system, and the hoisting component coordinate system cannot be completely aligned, resulting in errors in the use process. Therefore, a BIM and drone-based assembly type bridge component aerial installation positioning construction method considering cross-platform coordinate alignment and having high detection accuracy is needed. SUMMARY

[0005] To solve the above problems existing in the prior art, the application provides an assembly type bridge component aerial installation positioning construction method based on BIM and a UAV, which has the characteristics of considering cross-platform coordinate alignment and high detection precision.

[0006] The application aims can be achieved by the following technical solutions:

[0007] The assembly type bridge component aerial installation positioning construction method based on BIM and a UAV comprises the following steps:

[0008] Step one: BIM model construction, a three-dimensional BIM model containing all bridge components is established according to bridge design drawings, and the generation of construction data is completed;

[0009] Step two: UAV system configuration, a UAV with an RTK differential positioning system is selected according to requirements, a sensor module is installed on the UAV and calibrated, and then the flight path and task of the UAV are planned in the UAV flight control system according to the construction data generated by the BIM model;

[0010] Step three: completion of assembly type bridge component prefabrication and transportation;

[0011] Step four: the UAV flies according to the preset flight path and task, real-time monitors the bridge components in hoisting, and transmits the monitoring data to the ground control center; the ground control center fuses the monitoring data collected by the UAV and the BIM model through data matching and coordinate conversion algorithms, completes monitoring, and in the process, the ground control center judges the position drift value of the UAV in the hovering process; when the drift value exceeds a threshold value, the ground control center sends a hovering correction instruction to the UAV and stops receiving the UAV data.

[0012] As a preferred technical solution of the application, step five: after the construction is completed, all monitoring data collected by the UAV in the entire construction process are sorted and analyzed, and installation position data, attitude data and construction process images are integrated from the monitoring data.

[0013] As a preferred technical solution of the application, the step four further comprises: the UAV monitors the wind speed and transmits it to the ground control center; the ground control center judges whether the wind speed exceeds a threshold value; when the threshold value is exceeded, the ground control center corrects the coordinate values displayed by the collected monitoring data according to the wind speed.

[0014] As a preferred technical solution of the application, the step two further comprises: collecting historical assembly type bridge component installation deviation data and collecting corresponding construction condition data at the same time; cleaning the data to remove noise, abnormal values and missing values, filling the missing values by using an interpolation method, and unifying the data scale through normalization processing.

[0015] As a preferred technical solution of the present application, the step five further comprises: for the part that does not pass the bridge acceptance, the unmanned aerial vehicle is used to monitor and adjust again in the rectification process.

[0016] As a preferred technical solution of the present application, the step two further comprises: the BIM model is subjected to mechanical simulation; and the step four further comprises: the monitoring data is corrected according to the mechanical simulation data.

[0017] As a preferred technical solution of the present application, the step one further comprises: one or more parts on the surface in each component are taken as feature points in advance when the BIM model is constructed; and the step four further comprises: when the bridge component in hoisting is monitored in real time, the coordinates of the feature points are identified, the position deviation of the feature points relative to the BIM model is calculated, and an alarm is given when the position deviation is too large, wherein the position deviation comprises a distance difference and an angle difference.

[0018] As a preferred technical solution of the present application, the step four further comprises: in the judgment process of the position deviation being too large, whether the distance difference is too large is judged by a pre-set distance threshold value, whether the angle difference is too large is judged by a pre-set angle threshold value, then whether the difference between the distance difference and the distance threshold value or the interpolation value between the angle difference and the angle threshold value exceeds a preset value is judged, when one of the judgment results is yes, the size of the other threshold value is reduced and secondary judgment is performed.

[0019] The present application has the following beneficial effects:

[0020] The ground control center judges the position deviation value in the hovering process of the unmanned aerial vehicle, when the deviation value exceeds a threshold value, the ground control center sends a hovering correction instruction to the unmanned aerial vehicle and stops receiving the data of the unmanned aerial vehicle, thereby avoiding the collection of data with large errors when the monitoring precision is low due to the low flight precision of the unmanned aerial vehicle, and improving the detection precision.

[0021] When judging whether the wind speed exceeds a threshold value, the ground control center corrects the coordinate value displayed by the collected monitoring data according to the wind speed, thereby reducing the influence of environmental factors on the monitoring data and further improving the monitoring precision.

[0022] By correcting the threshold value of the monitoring data according to the mechanical simulation data, the judgment standard is improved when the requirements for prestress and other parameters are higher in some parts and the requirements for the installation part are more stringent, thereby further improving the detection precision. BRIEF DESCRIPTION OF DRAWINGS

[0023] In order to facilitate the understanding of those skilled in the art, the present application will be further described below with reference to the accompanying drawings.

[0024] Figure 1 The present application is a flowchart. Detailed Implementation

[0025] To further illustrate the technical means and effects of the present invention in achieving its intended purpose, the following detailed description of the specific implementation methods, structures, features, and effects of the present invention, in conjunction with the accompanying drawings and preferred embodiments, is provided.

[0026] Please see Figure 1 A method for aerial installation and positioning of prefabricated bridge components based on BIM and drones includes the following steps:

[0027] Step 1: BIM model construction. Based on the bridge design drawings, a 3D BIM model containing all bridge components is created, and construction data is generated.

[0028] Step 2: UAV system configuration. Select a UAV with an RTK differential positioning system according to the requirements, install and calibrate the sensor module on the UAV, and then plan the flight path and mission of the UAV in the UAV flight control system based on the construction data generated by the BIM model.

[0029] Step 3: Complete the prefabrication and transportation of assembled bridge components;

[0030] Specifically, when creating a BIM model, professional BIM software such as Revit and Bentley is used. In the software, a three-dimensional BIM model containing all bridge components, including piers, beams and connectors, is created based on the bridge design drawings.

[0031] During the modeling process, information such as the geometric dimensions, material properties, installation location and connection relationship of each component is first entered. Then, the surrounding environment such as the terrain and landform of the bridge construction site is modeled to form a complete BIM model of the construction scene, which provides a data foundation for subsequent construction simulation and positioning.

[0032] Subsequently, model optimization and collision checks were performed: the collision check function of BIM software was used to detect collisions between bridge component models to check for spatial interference issues between components. Then, the construction process was simulated using BIM software to identify potential problems during construction, such as hoisting path conflicts and insufficient installation space, and corresponding optimizations and adjustments were made.

[0033] Finally, construction data related to the installation and positioning of prefabricated bridge components are extracted from the optimized BIM model, including the three-dimensional coordinates, elevation, tilt angle, and installation sequence of the components. This data is then organized and classified and exported in specific data formats, such as CSV and XML, to facilitate subsequent data interaction and processing with the UAV system.

[0034] For the selection of unmanned aerial vehicle: in this embodiment, the unmanned aerial vehicle equipped with RTK differential positioning system and camera function is preferred, for example, DJI Jingwei M300RTK unmanned aerial vehicle is adopted, which can meet the high precision requirement of bridge component installation positioning in the air, and has long endurance time and large load capacity, and can carry various sensor devices;

[0035] Subsequently, the flight path should cover all areas where bridge components need to be installed, and ensure that the unmanned aerial vehicle can safely and stably obtain the required monitoring data during flight. At the same time, the flight height, speed, hovering time and other parameters of the unmanned aerial vehicle are set to meet the monitoring needs of different construction stages. In addition, a communication link between the unmanned aerial vehicle and the ground control center is established to ensure that the unmanned aerial vehicle can transmit monitoring data in real time and receive instructions from the ground control center;

[0036] In actual use, the unmanned aerial vehicle is easily affected by the cumulative path deviation during flight, or easily deviated by wind, and the flight accuracy and coordinate accuracy of the unmanned aerial vehicle cannot be compared with the completely digital modeling BIM data, and there is a probability that the BIM model coordinate system, the unmanned aerial vehicle coordinate system and the gimbal coordinate system, and the hoisting component coordinate system cannot be completely aligned, resulting in errors in use;

[0037] Therefore, it also includes step four: the unmanned aerial vehicle flies according to the preset flight path and task, monitors the hoisted bridge component in real time, and transmits the monitoring data to the ground control center. The ground control center fuses the monitoring data collected by the unmanned aerial vehicle and the BIM model through data matching and coordinate conversion algorithm to complete monitoring;

[0038] Specifically, the unmanned aerial vehicle pre-acquires the coordinates of the surrounding environmental factors in the construction site through monitoring, for example, when there is a hilltop of a hill near the construction site in the BIM modeling, the unmanned aerial vehicle monitors the hill, compares the position data of the hill with the position of the hill modeling in the BIM model, and completes data matching and coordinate conversion;

[0039] Subsequently, the ground control center calculates the distance according to the coordinate difference between the hill position data and the position of the hill modeling in the BIM model, the distance is expressed by Euclidean distance, and the ground control center pre-enters the coordinate difference threshold value;

[0040] When the distance exceeds the coordinate difference threshold value, the monitoring data obtained in the subsequent monitoring process is subtracted by the coordinate difference;

[0041] When the distance is lower than the coordinate difference threshold value, the monitoring data obtained in the subsequent monitoring process is subtracted by half of the coordinate difference;

[0042] At this point, the fusion of monitoring data and BIM model is completed;

[0043] In actual use, although the unmanned aerial vehicle is equipped with a positioning system to monitor its own position in real time, and then inversely deduce the position of the monitored component through its own position to complete the positioning of the component during construction, the unmanned aerial vehicle is usually equipped with a hovering stabilization algorithm to offset the sway caused by wind speed, thereby avoiding excessive sway caused by wind force when hovering. For example, in some cases, the local wind speed may suddenly increase, affecting the hovering stability of the unmanned aerial vehicle and thus affecting the measurement of the position of the monitored component.

[0044] Therefore, step four further comprises: during the monitoring of the unmanned aerial vehicle, the ground control center judges the position fluctuation value during the hovering of the unmanned aerial vehicle, and when the fluctuation value exceeds a threshold value, the ground control center sends a hovering correction instruction to the unmanned aerial vehicle and stops receiving data from the unmanned aerial vehicle.

[0045] Specifically, whether the local wind speed suddenly increases is determined by collecting wind speed in real time and judging the increasing speed of the wind speed. When the increasing speed of the wind speed exceeds a threshold value, it is determined that the local wind speed suddenly increases.

[0046] By judging the position fluctuation value during the hovering of the unmanned aerial vehicle through the ground control center, when the fluctuation value exceeds a threshold value, the ground control center sends a hovering correction instruction to the unmanned aerial vehicle and stops receiving data from the unmanned aerial vehicle, thereby avoiding the collection of data with large errors when the monitoring accuracy is low due to low flight accuracy of the unmanned aerial vehicle, and improving the detection accuracy.

[0047] In actual use, for the convenience of subsequent construction, all collected monitoring data need to be arranged and analyzed. Therefore, step five is further included: after the construction is completed, all monitoring data collected by the unmanned aerial vehicle during the entire construction process are arranged and analyzed, and installation position data, attitude data, and construction process images are integrated from the monitoring data.

[0048] In addition to the above-mentioned situation that the local wind speed suddenly increases, when the wind speed slowly increases to significantly affect the measurement, it will not trigger the determination. Therefore, step four further comprises: the unmanned aerial vehicle monitors the wind speed and transmits it to the ground control center, and the ground control center judges whether the wind speed exceeds a threshold value.

[0049] When the threshold value is exceeded, there is a high probability that the measurement will be significantly affected. At this time, the ground control center corrects the coordinate values displayed by the collected monitoring data according to the wind speed.

[0050] During the correction process, the ground control center pre-enters a correction function with wind speed as the independent variable, and the output value of the correction function is used to correct the coordinate values displayed by the collected monitoring data according to the wind speed.

[0051] When the wind speed is large, the output value of the correction function is high, and the monitoring data is relatively greatly corrected.

[0052] When the wind speed is small, the correction function output value is low, and the monitoring data is relatively small in amplitude;

[0053] By correcting the coordinate values displayed by the collected monitoring data according to the wind speed when judging whether the wind speed exceeds the threshold, the ground control center reduces the influence of environmental factors on the monitoring data, and further improves the detection accuracy.

[0054] The same bridge construction steps are usually taken for the same team, and the same bridge construction steps will bring the same deviation, so historical prefabricated bridge component installation deviation data can be collected to correct this part of the error. For this purpose, step two further comprises: collecting historical prefabricated bridge component installation deviation data, while collecting corresponding construction condition data; cleaning the data, removing noise and outliers and excavating missing values, filling the missing values by interpolation method, and unifying the data scale by normalization processing;

[0055] Specifically, the data after cleaning and missing value processing is used as available deviation data, and then during construction, the available deviation data is used as the correction value during BIM modeling. For example, if the available deviation data shows that the cross beam structure has a deviation of a from the theoretical position during past construction, then during the subsequent construction process, the position of the cross beam is corrected by-a during BIM modeling;

[0056] In order to supervise the rectification process of the part of the bridge that fails to pass the acceptance test, step five further comprises: for the part of the bridge that fails to pass the acceptance test, the unmanned aerial vehicle is used to monitor and adjust again during the rectification process.

[0057] Some parts have higher requirements for prestress and the like, and the requirements for the installation part are more stringent. General BIM modeling and collision detection are difficult to cover potential defects. Therefore, step two further comprises: performing mechanical simulation on the BIM model; and step four further comprises: correcting the monitoring data according to the mechanical simulation data.

[0058] By correcting the threshold of the monitoring data according to the mechanical simulation data, the judgment standard is improved when the requirements for prestress and the like are higher in some parts, and the requirements for the installation part are more stringent, and the detection accuracy is further improved.

[0059] For monitoring, it is usually impossible to monitor the position of each part of the entire component in real time, and it is necessary to select several reference points to represent the component position. Therefore, step one further comprises: during BIM model construction, one or more parts on the surface in each component are preselected as feature points, such as bolts or fixed strips on the surface of the component, and the theoretical position and theoretical angle of the feature points are set.

[0060] Subsequently, in step four, when the bridge member in hoisting is monitored in real time, the coordinates of the feature points are identified, in the embodiment, the positions of the bolts and the fixing strips are identified, then the position deviation of the feature points relative to the BIM model is calculated, and an alarm is issued when the position deviation is too large, wherein the position deviation includes a distance difference and an angle difference;

[0061] In the process of judging whether the position deviation is too large, whether the distance difference is too large is judged by the pre-set distance threshold, and whether the angle difference is too large is judged by the pre-set angle threshold;

[0062] The control system of the ground control center is pre-set with three constants, including the distance threshold, the angle threshold and the preset value, in the embodiment, when the position of the bolt is judged, firstly, the distance difference between the position of the bolt and the theoretical position of the bolt in the BIM model is judged, then the angle difference between the angle of the bolt and the theoretical angle in the BIM model is judged, and the angle is determined by the bolt axis;

[0063] Then, whether the difference between the distance difference and the distance threshold or the difference between the angle difference and the angle threshold exceeds the preset value is judged, when one of the judgment results is yes, the size of the other threshold is reduced and the second judgment is performed, for example, when the difference between the distance difference and the distance threshold exceeds the preset value, it represents that the distance deviation is large, at this time, if the member further deviates in the angle, the risk caused by the misplacement will be multiplied, therefore, the standard of the angle judgment needs to be improved, the angle threshold is reduced to ensure that the angle does not deviate to a large extent, similarly, when the difference between the angle difference and the angle threshold exceeds the preset value, it represents that the angle deviation is large, at this time, if the member further deviates in the distance, the risk caused by the misplacement will be multiplied, therefore, the standard of the distance judgment needs to be improved, the distance threshold is reduced to ensure that the distance does not deviate to a large extent.

[0064] The above is only a preferred embodiment of the present application, and does not limit the present application in any form, although the present application has been disclosed as above with the preferred embodiment, however, it is not intended to limit the present application, any person skilled in the art, without departing from the technical solution of the present application, can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, as long as it does not deviate from the technical solution of the present application, any modification, equivalent change and modification of the above embodiment according to the technical essence of the present application, all still belong to the scope of the technical solution of the present application.

Claims

1. A BIM and UAV based prefabricated bridge component aerial installation positioning construction method, characterized in that: Comprise the following steps: Step one: BIM model construction, according to the bridge design drawings, establish three-dimensional BIM model containing all bridge components, complete the generation of construction data; Step two: unmanned aerial vehicle system configuration, according to the demand, select unmanned aerial vehicle with RTK differential positioning system, install sensor module on unmanned aerial vehicle and calibrate, then according to the construction data generated by BIM model, plan the flight path and task of unmanned aerial vehicle in unmanned aerial vehicle flight control system; Step three: complete prefabrication and transportation of prefabricated bridge components; Step four: unmanned aerial vehicle flies according to the preset flight path and task, real-time monitors the bridge components in hoisting, and transmits the monitoring data to the ground control center, the ground control center fuses the monitoring data collected by the unmanned aerial vehicle and the BIM model through data matching and coordinate conversion algorithm, completes monitoring, in the process, the ground control center judges the position drift value of the unmanned aerial vehicle in hovering, when the drift value exceeds the threshold value, the ground control center sends hovering correction instruction to the unmanned aerial vehicle, and stops receiving the data of the unmanned aerial vehicle; The step four further comprises: the unmanned aerial vehicle monitors the wind speed and transmits it to the ground control center, the ground control center judges whether the wind speed exceeds the threshold value, when it exceeds the threshold value, the ground control center corrects the coordinate value displayed by the collected monitoring data according to the wind speed; The step one further comprises: when building the BIM model, one or several parts on the surface in each component are preselected as feature points; The step four further comprises: when real-time monitoring the bridge components in hoisting, the coordinates of the feature points are identified, the position deviation of the feature points relative to the BIM model is calculated, and an alarm is issued when the position deviation is too large, wherein the position deviation includes distance difference and angle difference.

2. The BIM and UAV-based assembly bridge component aerial installation positioning construction method according to claim 1, characterized in that: Further comprising step five: after the completion of construction, all monitoring data collected by the unmanned aerial vehicle in the whole construction process are sorted and analyzed, and installation position data, attitude data and construction process images are integrated from the monitoring data.

3. The BIM and UAV-based assembly bridge component aerial installation positioning construction method according to claim 2, characterized in that: The step two further comprises: collecting historical prefabricated bridge component installation deviation data, and collecting corresponding construction condition data at the same time; cleaning the data, removing noise and outliers and excavating missing values, filling the missing values by interpolation method, and unifying the data scale by normalization processing.

4. The BIM and UAV-based assembly bridge component aerial installation positioning construction method according to claim 2, characterized in that: The step five further comprises: for the part of the bridge that does not meet the acceptance, the unmanned aerial vehicle is used for monitoring and adjusting again in the rectification process.

5. The BIM and UAV-based assembly bridge component aerial installation positioning construction method according to claim 1, characterized in that: The step two further comprises: mechanical simulation of the BIM model; The step four further comprises: correcting the monitoring data according to the mechanical simulation data.

6. The BIM and UAV-based assembly bridge component aerial installation positioning construction method according to claim 5, characterized in that: The step four further comprises: in the process of judging whether the position deviation is too large, whether the distance difference is too large is judged by the pre-set distance threshold value, whether the angle difference is too large is judged by the pre-set angle threshold value, then whether the difference between the distance difference and the distance threshold value or the interpolation value of the angle difference and the angle threshold value exceeds the preset value is judged, when one of the judgment results is yes, the size of the other threshold value is reduced and the second judgment is made.

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