A three-dimensional laser scanning device integrating spatial positioning and its positioning and orientation method

Abstract

The present invention relates to a three-dimensional laser scanning device integrated with spatial positioning and a positioning and orientation method thereof, wherein the three-dimensional laser scanning device comprises a bracket, a lifting rod supported by the bracket, a three-dimensional laser scanner, a satellite orientation and positioning device and a bracket base, wherein the bracket base is connected to the bracket, one end of the lifting rod close to the bracket base is connected to the three-dimensional laser scanner, and the other end is connected to the satellite orientation and positioning device, and the three-dimensional laser scanner and the satellite orientation and positioning device are both provided with a wireless transmission module, and the three-dimensional laser scanning device adopts RTK positioning technology for positioning and short baseline orientation technology for orientation. Compared with the prior art, when the present invention is used, the operator hardly needs to go down the well, and only needs to put the three-dimensional laser scanner below the well neck, which has the advantages of high acquisition efficiency, high acquisition data accuracy, and high equipment stability and reliability.

Description

Technical Field

[0001] The present invention relates to the field of underground cable wells, and in particular to a three-dimensional laser scanning device integrating spatial positioning and a positioning and orientation method thereof. Background Art

[0002] With the continuous development and progress of science and technology, two-dimensional graphics and image data can no longer meet the needs of people's daily production and life. After continuous development, the relevant supporting equipment of three-dimensional visualization technology has gradually improved. The use of three-dimensional visualization technology can more intuitively, conveniently and accurately display the real situation. The application field of three-dimensional visualization technology is becoming wider and wider. Therefore, the demand for three-dimensional data acquisition in various industries in society is becoming more and more prominent. In the power system, how to efficiently and accurately obtain the target three-dimensional data and use three-dimensional visualization technology to provide accurate and traceable data to operation and maintenance personnel has always been a research hotspot in related fields.

[0003] Due to the dim light, narrow space and harsh environment in underground cable shafts, it is difficult to fully understand the internal conditions of the shaft even if personnel go down the shaft. The traditional method of collecting shaft data is inefficient, the data obtained is not accurate, and the final results of obtaining three-dimensional data are not ideal.

[0004] By using panoramic images to view the internal conditions of the cable shaft, the internal structure of the shaft can be clearly seen. Not only can the use of the cross-section pipe holes be intuitively viewed, but the threading of the cables inside the shaft can also be clarified. However, due to the dim light inside the shaft, it is difficult to obtain clear panoramic images using conventional photography methods. Summary of the invention

[0005] The purpose of the present invention is to overcome the defects of the above-mentioned prior art and to provide a three-dimensional laser scanning device and its positioning and orientation method that can obtain clear panoramic images in cable wells and improve the efficiency and accuracy of data collection and integrate spatial positioning.

[0006] The purpose of the present invention can be achieved by the following technical solutions:

[0007] A three-dimensional laser scanning device integrating spatial positioning, the three-dimensional laser scanning device comprising a bracket, a lifting rod supported by the bracket, a three-dimensional laser scanner, a satellite orientation positioning device and a bracket base, the bracket base being connected to the bracket, one end of the lifting rod close to the bracket base being connected to the three-dimensional laser scanner, and the other end being connected to the satellite orientation positioning device, the three-dimensional laser scanner and the satellite orientation positioning device being both provided with a wireless transmission module for connecting to a mobile device and transmitting detection data, and the lifting rod being marked with scales.

[0008] Furthermore, the satellite orientation positioning device includes a GNSS orientation positioning module and two satellite receiving antennas, the two satellite receiving antennas are both connected to the GNSS orientation positioning module, and the satellite receiving antennas and the GNSS orientation positioning module are both connected to the lifting rod.

[0009] Furthermore, the three-dimensional laser scanning equipment also includes a directional point position identification rod, which is connected to the lifting rod, and the directional point position identification rod is respectively connected to the satellite positioning antenna and the laser point cloud scanner, so that the angles of the directional point position identification rod, the satellite positioning antenna and the laser point cloud scanner remain consistent.

[0010] Furthermore, the three-dimensional laser scanning equipment also includes an auxiliary positioning device, which includes a laser emitter.

[0011] Furthermore, the three-dimensional laser scanning device also includes a device status indicator, which is connected to the GNSS positioning and orientation module, and the device status indicator is used to display basic information, including power status, battery power, device operating status, RTK operating status and 4G base station operating status.

[0012] Furthermore, the three-dimensional laser scanner is a phase-type three-dimensional laser scanner.

[0013] The present invention also provides a positioning and orientation method using the above-mentioned three-dimensional laser scanning equipment, which uses RTK positioning technology for positioning and short baseline orientation technology for orientation.

[0014] Furthermore, the RTK positioning technology includes the following steps:

[0015] Satellite positioning step: obtain the distance between the current position of the 3D laser scanning device and at least four satellites and the satellite positioning time, and solve the current position in the earth coordinate system; calculate the current position based on multiple satellite positioning systems, and perform error analysis to obtain the accuracy of the current position data;

[0016] Differential calculation step: positioning a preset fixed base station through a satellite positioning system, obtaining a positioning deviation, and correcting the positioning result of the three-dimensional laser scanning equipment according to the positioning deviation.

[0017] Furthermore, the short baseline orientation technology specifically obtains the carrier phase, pseudorange, Doppler and ephemeris data of the current epoch, uses the pseudorange difference technology to check and eliminate the gross errors of the acquired data, and establishes the GPS double-difference observation ambiguity and random model, uses the least squares method to solve the ambiguity floating point solution, uses the LAMBDA method to search out multiple ambiguity alternative solutions, uses the cumulative RMS algorithm to select the correct ambiguity from the alternative ambiguities, and uses the ambiguity bridging technology to improve the ambiguity search efficiency, obtain the correct ambiguity, and thus solve the lateral and longitudinal angles between the two satellite receiving antennas.

[0018] The present invention also provides another positioning and orientation method using the above-mentioned three-dimensional laser scanning equipment, using a laser transmitter to mark the position of special points in the scanned area, and using a total station to position and orient the scanning data of the three-dimensional laser scanner.

[0019] Compared with the prior art, the present invention has the following advantages:

[0020] (1) The three-dimensional laser scanning equipment of the present invention is equipped with a three-dimensional laser scanner and a satellite directional positioning device, adopts three-dimensional laser scanning technology, and integrates geographic coordinate positioning technology to realize rapid scanning of panoramic images and point cloud data inside the working well. When in use, the operator almost does not need to go down the well. It only needs to put the three-dimensional laser scanner below the well neck to quickly and accurately complete the collection of all elements of the working well information, thereby improving the efficiency of the operator in collecting the working well data.

[0021] (2) The present invention uses RTK positioning technology to obtain data on the center position of the scanner, and uses an orienteering instrument to align the point cloud. If the satellite positioning signal is weak and the position accuracy of the collected data does not meet the requirements, a reference position point can be provided, and then the point cloud data can be positioned and oriented using a total station. The positioning accuracy can reach the centimeter level, thereby ensuring the accuracy of the collected data and improving the reliability and availability of the collected data.

[0022] (3) The present invention is equipped with an orientation point position identification rod on the lifting rod corresponding to the direction of the satellite positioning antenna and the laser point cloud scanner, which can ensure that the accuracy of the orientation point position reaches the centimeter level.

[0023] (4) The support base of the present invention is provided with a pulley to facilitate the movement and adjustment of the equipment and improve the work efficiency of data collection.

[0024] (5) The present invention arranges an extension rod on the lifting rod to meet various needs arising during the mining process of the working well.

[0025] (6) The lifting rod and the extension rod of the present invention are both provided with gears, which can prevent the equipment from falling and causing losses due to misoperation; the bracket is equipped with a latch self-locking device, which can prevent the lifting rod from falling and facilitate the three-dimensional laser scanner to maintain its height for a long time, thereby improving the stability and reliability of the three-dimensional laser scanning device of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 A schematic diagram of the hardware structure of a three-dimensional laser scanning device integrating spatial positioning according to the present invention;

[0027] Figure 2 This is a schematic diagram of the overall structure of the three-dimensional laser scanning device integrated with spatial positioning of the present invention. DETAILED DESCRIPTION

[0028] The present invention is described in detail below in conjunction with the accompanying drawings and specific embodiments. This embodiment is implemented based on the technical solution of the present invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0029] Example 1

[0030] like Figure 1 and Figure 2 As shown, according to the characteristics of cable well data collection, in order to achieve high efficiency and safety of data collection, the collection equipment is required to be portable and easy to use. This embodiment provides a three-dimensional laser scanning device integrating spatial positioning, including a bracket 1, a lifting rod 3 supported by the bracket, a three-dimensional laser scanner 6, a satellite directional positioning device and a bracket base 2. The bracket base is connected to the bracket, and one end of the lifting rod close to the bracket base is connected to the three-dimensional laser scanner, and the other end is connected to the satellite directional positioning device.

[0031] The following is a detailed description of each component:

[0032] 1. Bracket

[0033] In order to facilitate the carrying and storage of the equipment during the collection process, the 3D laser scanning equipment adopts a modular design. Each equipment component can be disassembled for storage and assembled by yourself when in use. The bracket of the 3D laser scanning equipment is a triangular lifting bracket, which adopts a portable and movable design. The bracket base uses a detachable universal wheel to meet the ease of use, portability and safety of the equipment during the well collection process.

[0034] 2. Lifting rod

[0035] The equipment bracket is equipped with a portable lifting rod and extension rod 4 with scales. The default rod length is 1 meter. According to the on-site data collection situation, the default lifting rod is used with the extension rod to meet various needs that arise during the well collection process. The lifting rod and the extension rod both contain gears to prevent the equipment from falling and causing losses due to misoperation. Both support manual and semi-automatic lifting. The position of the lifting rod can be conveniently controlled through the lifting rod operating device 5. The lifting rod operating device is a screwdriver or an electric screwdriver.

[0036] 3. 3D laser scanner

[0037] The 3D laser point cloud scanner (3D laser scanner) is fixed under the lifting rod through a special fixing buckle. The lifting rod can be used to control the position of the laser scanner in the work pit, which is convenient for adjustment according to the depth of the work pit. The bracket is equipped with a latch self-locking device to prevent the lifting rod from falling due to accidents, and at the same time facilitate the 3D laser scanner to maintain its height for a long time.

[0038] 4. Satellite directional positioning device

[0039] The satellite orientation positioning device includes a GNSS orientation module and two centimeter-level precision satellite receiving antennas 7 to enhance the signal for obtaining satellite data. The lifting rod is also equipped with an orientation point position identification rod corresponding to the satellite antenna to ensure that the orientation point position accuracy reaches the centimeter level. The module supports RTK positioning and 4G base station positioning. The module is provided with a device status indicator 8, which provides basic information display through a status light, such as: power status, battery power, device operating status, RTK operating status and 4G base station operating status. In addition to the GNSS orientation module, the top of the three-dimensional laser scanning device is also specially equipped with an auxiliary positioning device, which is convenient for use when the satellite signal cannot be received or the received satellite position data does not meet the accuracy requirements. The special point position is marked in the scanned area by the manual dotting method, and then the total station is used to collect the data to ensure that the collected data is true and reliable. The GNSS orientation module includes an orientator.

[0040] 5. Auxiliary positioning equipment 10

[0041] The three-dimensional laser scanning equipment of this embodiment is also specially equipped with an auxiliary positioning device, which is convenient for use when no satellite signal can be received or the received satellite position data does not meet the accuracy requirements. The auxiliary positioning device includes a laser transmitter arranged on the top of the three-dimensional laser scanning equipment. The equipment uses dot marking to cooperate with the laser transmitter to mark the position of special points, and then uses the total station collection method to ensure that the collected data is true and reliable.

[0042] The following is a detailed description of the equipment selection, positioning and orientation method, equipment software and equipment advantages of the three-dimensional laser scanning equipment of this embodiment:

[0043] 1. Selection of 3D laser scanner

[0044] The selection of 3D laser scanner should be considered from the following points:

[0045] 1) Data accuracy of 3D laser point cloud scanning.

[0046] 2) The scanning range of the 3D laser scanner.

[0047] 3) The scanning speed of the 3D laser scanner.

[0048] Existing 3D laser scanners are mainly divided into two types, pulse type and phase type. The pulse type has a longer scanning distance but lower accuracy, and is suitable for terrain surveying and mapping. The phase type has a relatively short scanning distance but the acquired data has higher accuracy, and is suitable for scanning buildings and equipment.

[0049] According to the needs of cable pipeline data scanning, the scanning distance of the work well is relatively short, and the required data accuracy is relatively high. The scanning of the cable tunnel can be performed by setting multiple collection points, and the scanned data is aligned and spliced ​​to obtain complete data. For the collection of work well data, a phase-type 3D laser scanner is more suitable. The 3D laser scanning equipment invented this time uses FARO FocusM 70, which can provide IP54 dust and water protection, HDR imaging, a high-speed acquisition speed of 50,000 points / second and a larger operating temperature range. The scanning range can reach 70 meters, and the accuracy can reach + / -3mm. It can also use third-party software packages to customize suitable workflow software, which meets the requirements for the accuracy and speed of work well data collection during use.

[0050] 2. Positioning and Orientation Methods

[0051] According to the data collection specifications for cable wells, the plane coordinate system for collected data should use the CGCS2000 coordinate system, the elevation datum should use the 1985 national elevation datum, the dimensional accuracy of pipe holes, brackets and other facility components in the well should be less than 5 cm, the plane position accuracy should be less than or equal to 15 cm, the elevation accuracy should be less than or equal to 10 cm, and the attribute information should be standard and complete.

[0052] According to the requirements of the data collection specification, the positioning accuracy of traditional GPS is poor, and the positioning error of civil GPS can be as high as more than ten meters. These errors are mostly caused by the satellite clock difference and the multi-path effect of the atmosphere on the refraction of electromagnetic waves. Although the data collection package equipment uses GNSS (GPS, GLONASS, BDS, etc.) satellite positioning technology, relying solely on satellite positioning technology cannot meet the error requirements of data collection. In this invention, the data collection package equipment integrates RTK positioning technology and short baseline orientation technology to meet the requirements of the data collection specification.

[0053] RTK positioning technology is divided into two key points: satellite positioning and differential technology.

[0054] Satellite positioning is to measure the distance between the current location and at least four satellites and the corresponding time, and then solve the equation to get the current location in the earth coordinate system [x, y, z]. In order to ensure the accuracy of the data, the device will calculate the coordinates of the current location through GPS, GLONASS, and BDS respectively, and then perform error analysis based on the number of satellites connected and each positioning technology to obtain the accuracy of the location data.

[0055] The differential technology is to calculate the errors of the data obtained by the above-mentioned various GPS. By installing a fixed base station at a reference point with a known absolute position and comparing it with the positioning result of the GPS for the fixed base station, the deviation of the positioning signal can be obtained. Then, this deviation is sent to the collection set equipment that needs to be positioned, and a relatively accurate position signal of the collection point can be obtained. After calculation by this method, the positioning accuracy can reach the centimeter level, meeting the standard requirements of data collection.

[0056] The short baseline orientation technology used in this embodiment adopts a high-precision real-time dynamic orientation algorithm based on GPS, uses pseudo-range difference technology to check and eliminate gross errors, and establishes GPS double-difference observation fuzzy and random models, uses the least squares method to solve the ambiguity floating point solution, uses the LAMBDA method to search for a certain number of ambiguity alternative solutions, uses the cumulative RMS algorithm to select the correct ambiguity from the alternative ambiguities, and uses ambiguity bridging technology to improve the search efficiency of ambiguity. After obtaining the correct ambiguity, the horizontal and vertical angles between the antennas are calculated through the baseline solution. The direction of the device's geographical location can be accurately obtained through the short baseline orientation technology.

[0057] 3. Device Software

[0058] Laser point cloud equipment manufacturers provide data collection and processing software for some point clouds, but using only the software provided by the manufacturer cannot meet the requirements for accuracy and efficiency of collection. In order to ensure the accuracy and efficiency of data collection by the package equipment, the present invention also optimizes the software for the package equipment. In the present invention, RTK positioning services are integrated on the basis of the laser point cloud equipment SDK, and mobile terminal software for data collection is provided to facilitate the control of data collection and the checking of data collection quality. Through the integration of software, human intervention in the collection process can be reduced, ensuring the accuracy and efficiency of collected data.

[0059] 1) RTK positioning service

[0060] The working principle of RTK is to place a receiver on the base station and another one or several receivers on the carrier (called a mobile station). The observation value obtained by the base station lock is compared with the known position information to obtain the GPS differential correction value. This correction value is then transmitted to the mobile station to refine its GPS observation value, thereby obtaining a high-precision real-time position of the mobile station after differential correction. Differentials are divided into three categories according to their types: pseudo-differential, coordinate differential, and carrier phase differential. The RTK positioning service in the present invention adopts carrier phase differential technology. Compared with the first two positioning errors, the correlation of the positioning errors will not decrease rapidly as the spatial distance between the base station and the mobile station increases.

[0061] The RTK software technology in the present invention integrates network RTK technology, which is a multi-base station technology that uses the joint data of multiple reference stations for data processing. Through this RTK processing technology, there is no need to set up reference stations during field data collection, which reduces the operating cost during the collection process, improves collection efficiency, expands the operating radius, and can obtain equal accuracy within the network coverage area.

[0062] 2) Data collection mobile software

[0063] In order to facilitate the control of the acquisition equipment and check the quality of the collected data in real time, the present invention has developed a software client for the package equipment. The mobile phone can be used to conveniently configure the relevant parameters of the laser scanner equipment, control the scanner equipment to scan, and view the collected point cloud image map. The accuracy of the device position can also be viewed on the mobile terminal. According to the accuracy of the collected data, it can be determined whether the position data needs to be re-collected by the total station. The work wells that need to re-collect the position need to use auxiliary positioning tools to mark the ground to ensure the accuracy of the positioning and orientation when the total station is collected.

[0064] 4. Equipment advantages

[0065] The focus of underground cable well data collection is to improve the accuracy of collected data, reduce the complexity of using collection equipment, and improve the efficiency of data collection.

[0066] The accuracy of data is an important indicator for considering the results of data collection, and it also determines the reliability and availability of the collected data. To ensure the accuracy of the collected data, the three-dimensional laser scanning equipment integrated with spatial positioning in this embodiment uses three-dimensional laser scanning technology to obtain point cloud data of the real scene in the working well, uses RTK positioning technology to obtain data at the center of the scanner, and uses the orientation instrument to align the point cloud. If the satellite positioning signal is weak and the position accuracy of the collected data does not meet the requirements, a reference position point can be provided, and then the point cloud data is positioned and oriented by the total station.

[0067] Another key point in the data collection process is to improve the efficiency of collecting well data and improve the safety of the collection process. Traditional collection methods have defects in both efficiency and safety. The 3D laser scanning equipment provided in this embodiment adopts a method that does not require manual downhole operation. It only needs to place the 3D laser scanner in the 3D laser scanning equipment below the well neck to scan the real-time cloud data in the well. At the same time, the 3D laser scanning equipment is equipped with an equipment bracket and pulley to facilitate the movement and adjustment of the equipment and improve the work efficiency of data collection.

[0068] Through actual data collection and measurement, it is found that the three-dimensional laser scanning equipment of this embodiment is used to collect data on the work well equipment, and a method of no manual downhole operation is adopted. The data collection time for a single work well is about 5 to 10 minutes, and the data accuracy of all collected data is within 5 cmm, which fully meets the requirements of efficient, safe and accurate data collection in the power system for work wells.

[0069] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A positioning and orientation method for a three-dimensional laser scanning device using fusion spatial positioning, characterized in that: The three-dimensional laser scanning device comprises a bracket, a lifting rod supported by the bracket, a three-dimensional laser scanner, a satellite orientation positioning device and a bracket base, wherein the bracket base is connected to the bracket, one end of the lifting rod close to the bracket base is connected to the three-dimensional laser scanner, and the other end is connected to the satellite orientation positioning device, and the three-dimensional laser scanner and the satellite orientation positioning device are both provided with a wireless transmission module; The positioning and orientation method adopts RTK positioning technology for positioning and short baseline orientation technology for orientation; The RTK positioning technology includes the following steps: Satellite positioning step: obtain the distance between the current position of the 3D laser scanning device and at least four satellites and the satellite positioning time, and solve the current position in the earth coordinate system; calculate the current position based on multiple satellite positioning systems, and perform error analysis to obtain the accuracy of the current position data; Differential calculation step: positioning a preset fixed base station through a satellite positioning system, obtaining a positioning deviation, and correcting the positioning result of the three-dimensional laser scanning device according to the positioning deviation; The short baseline orientation technology specifically includes: obtaining the carrier phase, pseudorange, Doppler and ephemeris data of the current epoch, using the pseudorange difference technology to check and eliminate the gross errors of the obtained data, and establishing the GPS double-difference observation ambiguity and random model, using the least squares method to solve the ambiguity floating point solution, using the LAMBDA method to search out multiple ambiguity alternative solutions, using the cumulative RMS algorithm to select the correct ambiguity from the alternative ambiguities, and using the ambiguity bridging technology to improve the ambiguity search efficiency, and obtain the correct ambiguity, so as to solve the lateral and longitudinal angles between the two satellite receiving antennas.

2. The positioning and orientation method of a three-dimensional laser scanning device using fusion spatial positioning according to claim 1, characterized in that: The satellite orientation positioning device comprises a GNSS orientation positioning module and two satellite receiving antennas, the two satellite receiving antennas are both connected to the GNSS orientation positioning module, and the satellite receiving antennas and the GNSS orientation positioning module are both connected to the lifting rod.

3. The positioning and orientation method of a three-dimensional laser scanning device using fusion spatial positioning according to claim 2, characterized in that: The three-dimensional laser scanning device also includes a directional point position identification rod, which is connected to the lifting rod. The directional point position identification rod is respectively connected to the satellite receiving antenna and the laser point cloud scanner, so that the angles of the directional point position identification rod, the satellite receiving antenna and the laser point cloud scanner remain consistent.

4. The positioning and orientation method of a three-dimensional laser scanning device using fusion spatial positioning according to claim 2, characterized in that: The three-dimensional laser scanning device also includes an auxiliary positioning device, which includes a laser emitter.

5. The positioning and orientation method of a three-dimensional laser scanning device using fusion spatial positioning according to claim 1, characterized in that: The three-dimensional laser scanning device also includes a device status indicator, which is connected to the GNSS positioning and orientation module. The device status indicator is used to display basic information, including power status, battery power, device operating status, RTK operating status and 4G base station operating status.

6. The positioning and orientation method of a three-dimensional laser scanning device using fusion spatial positioning according to claim 1, characterized in that: The three-dimensional laser scanner is a phase-type three-dimensional laser scanner.

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