High-precision and rapid positioning method for pipe joint sinking process based on fusion of GPS and inertial navigation system

Abstract

The application discloses a high-precision and rapid positioning method for pipe joint sinking based on GPS and inertial navigation system fusion, and comprises the following steps: constructing a dynamic monitoring system for the structure position and posture of a moving object, wherein the monitoring system comprises at least one GPS and inertial navigation system; processing observation data obtained by the GPS and inertial navigation system to obtain a high-precision and continuously-distributed data sequence; constructing a rigid body motion model of the pipe joint and a coordinate dynamic conversion mode, and using the observation data of the GPS and the observation data of the inertial navigation system to rapidly calculate underwater control point engineering coordinates. According to the application, underwater environment simulation driven by monitoring data and real-time visual intelligent control of docking states are realized, and microsecond-level high-precision synchronization of observation data is realized.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tunnel water pipe installation, and particularly relates to a high-precision and rapid positioning method for pipe section sinking process based on GPS and inertial navigation system fusion. BACKGROUND

[0002] The underwater butt joint of the immersed tube tunnel pipe section has high precision requirements, and the installation and lamination technology of the butt joint section and the waterproof joint is difficult. On the other hand, during the pipe section sinking installation process, due to the complexity of the wind wave flow environmental factors, the coordinate position and the spatial posture of the pipe section have randomness and uncertainty, and in addition, the conventional measurement method is difficult to obtain coordinate data meeting the construction requirements after the structure is sunk underwater, so the pipe section sinking process depends on the diving detection operation to a certain extent, which makes the pipe section sinking installation in the complex flow field uncertain and has great risk hidden dangers.

[0003] The immersed tube tunnel pipe section has a huge volume and quality, and the dragging and sinking movement in the water has a large inertia, and in addition, the stress and displacement of the dragging system have hysteresis characteristics, so once the position of the butt joint control point is abnormal and deviates when approaching, it will be difficult to correct immediately and cause large installation splicing errors or even technical failures. In the engineering, high-precision coordinate values (relative position and posture) of the underwater butt joint control point need to be obtained in time in order to quickly feedback and pre-control the movement trend of the pipe section, so as to achieve intelligent feedback control and avoid deviation overrun.

[0004] In view of the above, it is urgent to develop a high-precision and rapid positioning and real-time visualization intelligent measurement and control method for pipe section sinking process without relying on ground measurement base points. SUMMARY

[0005] In view of the deficiencies in the prior art, the purpose of the present application is to provide a high-precision and rapid positioning method for pipe section sinking process based on GPS and inertial navigation system fusion, to realize underwater environment simulation and real-time visualization intelligent control of butt joint state driven by monitoring data, and to realize microsecond-level high-precision synchronization of observation data. In order to achieve the above purposes and other advantages according to the present application, a high-precision and rapid positioning method for pipe section sinking process based on GPS and inertial navigation system fusion is provided, comprising:

[0006] A dynamic monitoring system for the position and posture of a moving object structure is constructed, the monitoring system comprising at least one GPS and inertial navigation system; the GPS and inertial navigation system are installed on the pipe section set position at the same time, respectively connected to the data terminal control computer, and the time trigger, sampling time interval and synchronization accuracy are set on the two systems to realize microsecond-level high-precision synchronization of observation data.

[0007] The observation data obtained by the GPS and inertial navigation system are processed to obtain a high-precision continuous distributed data sequence; on the basis of fault tolerance tolerance processing of observation data, a quadratic spline regression fusion Gaussian interpolation method is used to realize high-precision of massive data and dynamic continuous reconstruction of sequence integrity.

[0008] The rigid body motion model and coordinate dynamic conversion mode of the pipe section are constructed, the influence of deformation observation accuracy is ignored, the rigid body motion model and coordinate dynamic conversion mode of the pipe section are constructed, and the observation data of the GPS and inertial navigation system are directly used for rapid calculation of underwater control point engineering coordinates.

[0009] The tunnel site area electronic chart and the pipe section 3D design chart are connected to the database and connected to the engineering coordinate system, the digital twin and the pipe section model are realized by using the VTK and PSM systems, the underwater environment simulation driven by the monitoring data and the real-time visual intelligent control of the docking state are realized, the pipe section docking state is fed back to the construction in the form of relative coordinates and simulation video in real time, and the visual intelligent control of the pipe section sinking and docking process is realized.

[0010] i) the GPS and the inertial navigation system are combined to realize high-precision synchronization of position and attitude coordinate data at the microsecond level; ii) the spline regression and the Gaussian interpolation are combined to process random errors and data sample loss, and a high-precision continuous distributed data sequence is obtained; iii) the rigid body motion model and the coordinate conversion method of the pipe section are used to establish a rapid calculation method of underwater control point engineering coordinates; iv) the underwater environment simulation and the real-time visual intelligent control of the docking state.

[0011] The application is suitable for real-time visual monitoring of underwater installation of a immersed tube tunnel project, and fills the gap of related technologies at home and abroad. BRIEF DESCRIPTION OF DRAWINGS

[0012] Figure 1 It is a structure schematic diagram of the GPS and the inertial navigation system combined according to the pipe section sinking process high-precision rapid positioning method based on fusion of the GPS and the inertial navigation system of the application;

[0013] Figure 2 It is a data processing method schematic diagram of the pipe section sinking process high-precision rapid positioning method based on fusion of the GPS and the inertial navigation system of the application;

[0014] Figure 3 It is a pipe section coordinate system schematic diagram of the pipe section sinking process high-precision rapid positioning method based on fusion of the GPS and the inertial navigation system of the application;

[0015] Figure 4A tunnel pipe section GPS monitoring point arrangement schematic diagram for the high-precision and rapid positioning method of pipe section sinking process based on GPS and inertial navigation system fusion according to the application;

[0016] Figure 5 A pipe section end face control point position and coordinate schematic diagram for the high-precision and rapid positioning method of pipe section sinking process based on GPS and inertial navigation system fusion according to the application;

[0017] Figure 6 A pipe section sinking process high-precision and rapid positioning method based on GPS and inertial navigation system fusion according to the application. DETAILED DESCRIPTION

[0018] The technical solutions in the embodiments of the application will be clearly and completely described below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, rather than all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative efforts fall within the protection scope of the application.

[0019] Reference Figure 1 The high-precision and rapid positioning method of pipe section sinking process based on GPS and inertial navigation system fusion comprises the following steps.

[0020] High-precision synchronous monitoring system: a dynamic monitoring system of motion object structure position and attitude independent of ground measurement reference points is constructed by combining GPS and inertial navigation system. The system is composed of two GPS receiving antennas and one inertial navigation system, which are respectively installed on the measurement towers after pipe section outfitting, are respectively connected to a data terminal control computer, and are set with time triggering, sampling time interval and synchronization accuracy on the two systems to realize microsecond-level high-precision synchronization of multi-sequence observation data. Real-time dynamic coordinates of the pipe section are determined through GNSS and inertial navigation synchronous data coordination algorithm and error analysis processing method. Figure 1

[0021] High-precision and continuous data samples: due to the precision and environmental factors (for example, bad weather, etc.) of GPS and inertial navigation system, system errors, accidental errors and gross errors exist in GNSS and inertial navigation observation data, or accidental factors will cause data loss. These abnormal data must be processed scientifically. The application sets a fault tolerance mode to effectively filter signal noise. Then, the observation data samples after signal noise cleaning processing are supplemented with missing data by Gauss interpolation, and random error processing and data sequence continuous distribution reconstruction are performed through spline regression to obtain high-precision and continuous distribution data sequence. The calculation model and method are shown in Figure 2

[0022] ​​Underwater coordinate calculation based on observation data and rigid body motion model:

[0023] Ignoring the influence of pipe segment deformation on the monitoring results, a pipe segment rigid body motion model and coordinate dynamic conversion method are constructed, and GNSS and inertial navigation observation data of the surface measurement tower are used for rapid calculation of underwater control point engineering coordinates. Specifically, i) according to the size and geometric shape of the pipe segment, a local coordinate system of the pipe segment is established and an underwater positioning control point is set, and the engineering coordinate system (engineering regional coordinates based on WGS-84) is obtained through coordinate transformation. According to the real-time synchronous observation data of GPS and inertial navigation and the pipe segment rigid body coordination calculation method, the dynamic coordinates (x i ,y i ,z i ) of each positioning point at the same step (i = 1, 2, 3,..., n) and the coordinate difference (Δx i ,Δy i ,Δz i ) with the fixed end are calculated rapidly, as shown in Figures 3-5 .

[0024] Real-time visualization of environmental simulation and docking state: The tunnel site area is modeled as an electronic chart, the pipe segment design CAD drawing and underwater foundation groove design drawing are 3D modeled in the engineering coordinate system, connected to the database and connected to the engineering coordinate system, the local environment of the engineering area is reconstructed and high-precision data is imported in real time, and the computer interface displays the pipe segment position, attitude, coordinate increment between docking points, etc. in real time; at the same time, VTK and PSM systems are used to realize digital twin and real-time driving of pipe segment model, realize real-time visualization, remote sharing and intelligent control of underwater environment simulation and docking state driven by monitoring data. As shown in Figure 6 .

[0025] Example 1

[0026] 1. Monitoring system

[0027] Considering that the pipe segment of the immersed tunnel is in a moving state in water during the installation process, the position and attitude change with time and are affected by the flow field and the towing traction system, and the high-precision measurement of the underwater positioning point is difficult. The present application adopts the combination of GPS (Beidou) and inertial navigation system to jointly constitute a real-time monitoring system for the position and attitude of the pipe segment during the sinking process. Two GNSS measurement antennas and one inertial navigation system are installed on the front and rear measurement towers after pipe segment outfitting, as shown in the figure.

[0028] The monitoring system simultaneously excites the GPS and inertial navigation system through the satellite electronic clock, realizes high-frequency and high-precision synchronous data acquisition of the position coordinates of the two monitoring points and the rotational displacement of the inertial system monitoring point around the three orthogonal coordinate axes (i.e. the attitude of the pipe segment).

[0029] System structure module composition and function:

[0030] (1) GPS: responsible for reading data from GPS surveying instrument and writing into local database.

[0031] (2) Inertial navigation system: responsible for reading data from inertial navigation system and writing into local database.

[0032] (3) Local database (SQL Server): save new surveying data but not uploaded to central database.

[0033] (4) Surveying agent: responsible for reading data from local database and uploading to central database. The agent accesses remote surveying data service through SOAP WebService protocol. If network connection is not available, the agent will try to reconnect periodically, and once the connection is available, the agent will upload all data saved in local database.

[0034] (5) Surveying data service: responsible for listening and receiving data uploaded from surveying agent and saving to central database. The service runs in Tomcat Server and exposes interface through SOAP WebService.

[0035] (6) Central database (SQL Server): responsible for saving all field surveying data.

[0036] 2. High-precision serialization processing of monitoring data

[0037] Surveying errors are divided into systematic errors, accidental errors and gross errors.

[0038] Based on error theory analysis, according to the design specification requirements of pipe joint sinking, the application constructs a fault-tolerant method, filters gross errors and accidental errors of large order of magnitude. For the data missing (or data missing caused by system failure or environmental factors in the collection process) in the original data sequence formed after the gross error elimination and accidental error removal, the time sequence integrity of the data sequence sample number is tested, then the missing data is supplemented by Gaussian interpolation, and then the random error processing and data sequence continuous distribution reconstruction are performed through spline regression, to obtain a high-precision continuous distribution data sequence. The calculation model and method are as shown in Figure 6 .

[0039] Based on the conditions of limited sample space and sample number, the application uses mean error as a numerical standard for measuring observation accuracy, also known as "standard deviation" or "root mean square error" of limited test. Since the true error is not easy to obtain, the observation value correction number obtained by the least square method is used to replace the true error. The size of the mean error is used to evaluate the accuracy of the observation value, and the calculation formula is as shown in (1):

[0040]

[0041] 3. Pipe segment underwater positioning point coordinate calculation

[0042] 1) Pipe segment rigid body motion model

[0043] Ignoring the influence of pipe segment deformation on the monitoring results, a pipe segment rigid body motion model and coordinate dynamic conversion method are constructed, and GNSS and inertial navigation observation data of the surface measurement tower are used for rapid calculation of underwater control point engineering coordinates through rigid body displacement transmission mode.

[0044] 2) Pipe segment centroid coordinates

[0045] Considering that the engineering independent coordinate system is (X s ,Y s ,Z s ), taking the pipe segment centroid as the coordinate origin, the pipe segment coordinate system is (X c ,Y c ,Z c ). As shown in Figure 3 .

[0046] According to the monitoring scheme, 2 GPS measurement points and 1 attitude observation point are set on each pipe segment. As shown in Figure 4 .

[0047] The corresponding pipe segment coordinates are P1(X c ,Y c ,Z c ) and P2(X c ,Y c ,Z c ). The corresponding engineering coordinates (GPS measurement conversion results) are P1(X s ,Y s ,Z s ) and P2(X s ,Y s ,Z s ). The coordinate rotation based on the engineering coordinate system obtained by the inertial navigation is (α, β, θ).

[0048] According to the coordinate conversion relationship:

[0049]

[0050] Then the engineering coordinate value of the pipe segment centroid is:

[0051]

[0052] In the above formula, r ij (1,2,3) is the rotation matrix. Let R(α), R(β), and R(θ) be the rotation matrices around the X, Y, and Z axes of the engineering coordinate, respectively, and the total rotation matrix is as follows.

[0053]

[0054] Substitute the above equation into equation (2) to obtain the centroid coordinates (X co ,Y co ,Z co ) of the pipe section corresponding to the engineering coordinates as the coordinates of the model driving points.

[0055] 3) Calculation of the coordinates of the specific points of the pipe section cross section

[0056] The control points of the pipe section end face are shown in the following table. Figure 5

[0057] Suppose the nominal size of the pipe section is [L, D, h] (for non-rectangular planar pipe sections, the prismatic body with four corner points can be calculated), and the coordinate values of the control points corresponding to the coordinate system of the pipe section are k1(L / 2, D / 2, 0), k2(L / 2, 0, h / 2), k3(L / 2, -D / 2, 0), and k4(L / 2, 0, -h / 2), respectively.

[0058] Take (X co ,Y co ,Z co ) obtained by the above calculation as the coordinate translation values, and the coordinate values of the control points corresponding to the engineering coordinate system can be calculated using the following equations, respectively.

[0059]

[0060] In equation (5), for the same sampling time, the calculation method and result of the rotation matrix remain unchanged, and the coordinate origin corresponding to the pipe section coordinate system remains unchanged (dynamic coordinate system - changes with the sampling time).

[0061] 4. Environmental simulation

[0062] 1) 3D modeling of drawing data

[0063] The 3D digital model is configured using the PSM file mode. The environmental related drawing data of the immersed tube structure, river bed, and surrounding buildings are 3D modeled and integrated into the engineering coordinate system. This includes: i) design drawing data such as tunnel site surrounding floatation route design drawings and immersed tube pipe section structure design CAD drawings, foundation trench and sinking control design process drawings; ii) construction process and environmental related data such as electronic charts and scene photographic images; iii) pipe section position and state related data such as GPS monitoring data and inertial navigation data.

[0064] 2) 3D graphics rendering

[0065] ​A unified 3D simulation graphics is built based on the third-party library VTK. An external application module organizes three-dimensional data into a data structure recognized by the rendering engine according to the requirements of the rendering engine, and then transmits the three-dimensional data to the rendering engine; the rendering engine calls the device management module as needed; finally, a virtual device encapsulating hardware APIs such as DirectX and OpenGL draws three-dimensional graphics on the screen.

[0066] Real-time visualization of the docking state

[0067] The tunnel address area is modeled into an electronic sea chart, the pipe joint design CAD chart and the underwater foundation trench design chart are modeled into 3D models in the engineering coordinate system, connected to the database and connected to the engineering coordinate system, the local environment of the engineering area is reconstructed, and high-precision data is imported in real time, and the computer interface displays the pipe joint position, posture, coordinate increment between docking points, etc. in real time; at the same time, the Windows Form system is used to realize digital twin and real-time driving of the pipe joint model, realize underwater environment simulation driven by monitoring data, real-time visualization of the docking state, remote sharing and intelligent control.

[0068] 1) Subprogram composition

[0069] The visualization module is an independent executable application program, which is composed of the following subprograms.

[0070] (1) Software interface: The main interface of the application program is based on Windows Form technology.

[0071] (2) Model management and import: A set of extensible model management system and import function implementation is established, and model information is configured in detail based on an externally configurable psm file.

[0072] (3) Graph rendering module: Fast and efficient implementation of three-dimensional model rendering is one of the key modules of the entire program, which is built based on the third-party library VTK.

[0073] (4) Data acquisition module integration and model driving: This sub-module is the core of the entire program, and is also the data source for data analysis and construction guidance. This module directly accesses the real-time database of the immersed tube.

[0074] (5) Real-time data generation: Based on the data acquisition module, this sub-module can dynamically output construction-related data to guide construction, and is one of the key modules of the system.

[0075] (6) Relationship diagram between various modules of the system: as shown in Figure 6 .

[0076] 2) Model management and import

[0077] The three-dimensional model of the sinking site is established, which will greatly improve the visualization of the floating and sinking process. In order to improve the authenticity of visualization, not only the actual monitoring of the sinking pipe model needs to be established, but also the related tower, cable, dry hole, foundation trench and surrounding environmental facilities are involved.

[0078] However, if the relevant model information is constructed in the application program, the coupling between the application program and the model information is greatly improved, so that the application program cannot be realized. Therefore, how to reduce the coupling between the core code of the application program and the model is the premise of software scalability. Of course, the scalability of the application program to the model will greatly improve the possibility of software application to other projects.

[0079] 3) Data acquisition module integration and model driving

[0080] When the system is running in real-time monitoring mode, the data acquisition module will monitor the sinking pipe database every 100 ms (program set time density), and once new data is generated, the system will be notified and the latest data will be transmitted to the system. When the system runs in the playback monitoring model, the data acquisition model will not actively notify the system, but the system will query the sinking pipe database and obtain related information according to the current user specified playback time. As shown in Figure 6

[0081] The number of devices and the scale of processing described herein are used to simplify the description of the present application, and the application, modification and change of the present application are obvious to those skilled in the art. Although the embodiments of the present application have been disclosed as above, it is not limited to the application and modification listed in the specification and the embodiment, and it can be fully applied to various fields suitable for the present application, and other modifications can be easily realized by those skilled in the art, therefore, the present application is not limited to specific details and the figures shown and described herein, without departing from the general concept defined by the claims and the equivalent scope.​

Claims

1. A high-precision and rapid positioning method for pipe segment placement based on the fusion of GPS and inertial navigation system, characterized by: include: Constructing a dynamic monitoring system for the structural position and attitude of a moving object, the monitoring system including at least one GPS and an inertial navigation system; Processing the observation data obtained by the GPS and inertial navigation system to obtain a high-precision continuously distributed data sequence; Construct a rigid body motion model for pipe segments and a dynamic coordinate conversion method, and use GPS observation data and inertial navigation system observation data for rapid calculation of engineering coordinates of underwater control points; Electronic nautical charts of the tunnel site area and 3D design drawings of pipe segments were connected to the database and the engineering coordinate system. VTK and PSM systems were used to implement real-time drive of digital twins and pipe segment models, enabling underwater environment simulation driven by monitoring data and real-time visual intelligent control of docking status. The processing of the observed data is specifically to perform signal-noise cleaning on the observed data, and then use Gaussian interpolation to supplement the cleaned missing data, and then use spline regression to process random errors and reconstruct the continuous distribution of the data sequence to obtain a high-precision continuously distributed data sequence; The method of using the GPS observation data and the inertial navigation system observation data for the rapid calculation of the engineering coordinates of the underwater control points is specifically as follows: According to the size and geometry of the pipe segment, establish the local coordinate system of the pipe segment and set the underwater positioning control points; Obtain engineering coordinate system through coordinate transformation; Based on the real-time synchronous observation data of GPS and inertial navigation system and the coordinated calculation method of pipe segment rigid body, the dynamic coordinates of each positioning point at the same time and the coordinate difference between the pipe segment and other fixed ends are quickly calculated.

2. The high-precision and rapid positioning method for pipe segment sinking process based on the fusion of GPS and inertial navigation system according to claim 1 is characterized in that: The GPS and inertial navigation system are installed on the measuring tower after the pipe segment is outfitted, and the GPS and inertial navigation system are respectively connected to the data terminal control computer, and the time excitation, sampling interval and synchronization accuracy are set on the two systems. The real-time dynamic coordinates of the pipe segment are determined through the coordination algorithm and error analysis processing method of the GPS and inertial navigation system synchronization data.

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