In-pipe robot positioning method and system suitable for trenchless deep-buried pipelines

Abstract

The present invention discloses a method and system for positioning an in-pipe robot suitable for trenchless deep-buried pipelines. The method relates to the field of robot positioning technology and can be applied to the field of pipeline detection. The main purpose is to solve the problem that the existing in-pipe robot cannot balance the endurance and signal detection strength, resulting in low applicability to different pipeline detection scenarios. The method mainly includes the following steps: the in-pipe robot synchronously receives electromagnetic signals sent by the auxiliary inspection robot outside the pipe through a transmitter array through multiple receivers carried by the in-pipe robot; the relative position coordinates of the in-pipe robot and the auxiliary inspection robot outside the pipe are calculated based on the reception time of all electromagnetic signals received by each receiver to obtain the target relative position coordinates; the in-pipe positioning coordinates are calculated based on each group of relative position coordinates, and the weighted average calculation is performed based on the in-pipe positioning coordinates and the in-pipe positioning coordinates of the positioning sensor to obtain the target in-pipe positioning coordinates. The method is mainly used for in-pipe robot positioning.

Description

Technical Field

[0001] The present invention relates to the field of robot positioning technology and can be applied to the field of pipeline detection, and in particular to an in-pipe robot positioning method and system suitable for trenchless deep-buried pipelines. Background Art

[0002] Pipelines carry the vital task of transporting energy, offering low transportation costs and ensuring safety and reliability. Oil and gas pipeline accidents caused by leaks are common, making regular maintenance and repair crucial. Currently, a widely used maintenance method involves using in-pipeline detection robots equipped with relevant equipment to detect pipeline defects, followed by in-pipeline repair robots that repair the defects. Extremely low frequency (ELF) communication technology, due to its high penetration and ability to overcome electromagnetic shielding to a certain extent, is widely used for in-pipeline robot positioning.

[0003] Currently, pipeline robot positioning methods based on ELF communication technology primarily include patching and in-pipe signaling. Patching involves installing an ELF signaling system at a location on the pipeline corresponding to the defect detected by the pipeline inspection robot. When the in-pipe robot passes this location, it receives the transmitter signal and locates itself. However, this method is only applicable in trenching scenarios. In-pipe signaling involves the pipeline repair robot carrying an ELF signaling and receiving system, which periodically transmits ELF signals. An antenna array outside the pipeline receives the ELF signal, locates its source, and transmits this location data back to the in-pipe robot. While this method is applicable in trenchless scenarios, due to the limited energy storage of the in-pipe robot, continuous ELF signaling significantly reduces its flight time. To ensure the robot's endurance as much as possible, the ELF signaling system it carries is mostly low-power. The transmitted signal is attenuated by media such as the pipe wall and soil. The signal strength received at the antenna array is extremely low and is also extremely weak compared to the background noise of the same frequency. This places high demands on the resolution capability and detection algorithm of the antenna array, making it impossible to balance the endurance of the robot in the pipe and the signal detection strength, resulting in low applicability to different pipeline detection scenarios. Summary of the Invention

[0004] In view of this, the present invention provides an in-pipe robot positioning method and system suitable for trenchless deep-buried pipelines. The main purpose is to solve the problem that the existing ELF-based robot detection method cannot balance the robot's endurance and signal detection strength, resulting in low applicability to different pipeline detection scenarios.

[0005] According to one aspect of the present invention, a method for positioning a robot in a trenchless deep-buried pipeline is provided, comprising:

[0006] The electromagnetic signals sent by the auxiliary inspection robot outside the pipe through the transmitter array are synchronously received by the multiple receivers carried by the robot inside the pipe;

[0007] Calculating the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe according to the reception time of all electromagnetic signals received by different receivers to obtain the relative position coordinates of the target;

[0008] When the target relative position coordinates meet a preset relative offset threshold, calculating the auxiliary positioning coordinates outside the tube according to the target relative position coordinates;

[0009] A weighted average calculation is performed based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the target positioning coordinates inside the tube.

[0010] Furthermore, the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe are calculated based on the reception time of all electromagnetic signals received by the different receivers to obtain the target relative position coordinates, including:

[0011] For each receiver, the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe are calculated based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter arrays, and multiple groups of initial relative position coordinates determined according to the electromagnetic signals emitted by different transmitter arrays under each receiver are obtained;

[0012] All of the initial relative position coordinates are converted to the same coordinate system, and the multiple sets of initial relative position coordinates after the coordinate conversion are processed by least square method to obtain the target relative position coordinates.

[0013] Furthermore, the calculation of the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter array includes:

[0014] Calculating the reception time difference of each of the peripheral transmitters relative to the central transmitter;

[0015] Constructing a surface equation based on the reception time difference of each peripheral transmitter, the relative distance of the peripheral transmitter to the central transmitter, the electromagnetic wave propagation velocity in the soil, and the relative position coordinate variables corresponding to the transmitter array to obtain a surface equation between each peripheral transmitter and the receiver;

[0016] With the goal of minimizing the sum of squared errors between each surface equation and the approximate intersection point, the relative position coordinate variables in the surface equation are approximately solved using the least squares method to obtain the initial relative position coordinates determined based on the electromagnetic signal emitted by the transmitter array.

[0017] Furthermore, the weighted average calculation is performed based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the target positioning coordinates inside the tube, including:

[0018] Retrieving weights corresponding to the odometer sensor group, the inertial sensor group, and the receiver respectively;

[0019] The target in-pipe positioning coordinates are obtained by performing a weighted average calculation based on the real-time in-pipe positioning coordinates collected by different positioning sensor groups and their corresponding weights, as well as the auxiliary positioning coordinates outside the pipe and the weights corresponding to the receivers.

[0020] Furthermore, after performing weighted average calculation based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the target positioning coordinates inside the tube, the method further includes:

[0021] During the process of the in-tube robot moving along the moving trajectory determined by the target in-tube positioning coordinates, the robot continuously calculates the auxiliary positioning coordinates outside the tube, and collects the in-tube positioning coordinates in real time through the different types of positioning sensor groups carried by the robot;

[0022] When the travel distance reaches a preset distance, the historical external auxiliary positioning coordinates and historical internal positioning coordinates within the preset distance are obtained, as well as the real-time external auxiliary positioning coordinates and real-time internal positioning coordinates;

[0023] For each type of positioning sensor group, a weight update calculation is performed based on the historical in-tube positioning coordinate data, the real-time in-tube positioning coordinates, and the corresponding weights to obtain a first target update weight;

[0024] Performing a weight update calculation based on the real-time off-pipeline auxiliary positioning coordinates, the historical off-pipeline auxiliary positioning coordinates, and the weight of the corresponding receiver to obtain a second target update weight;

[0025] The weights corresponding to the different types of positioning sensor groups in the weighted average calculation process are updated using the first target update weight, and the weights corresponding to the receivers are updated using the second target update weight.

[0026] Furthermore, the method further comprises:

[0027] Obtain the odometer positioning coordinates from the odometer carried by the in-tube robot;

[0028] When the difference between the odometer positioning coordinates and the auxiliary positioning coordinates outside the tube is greater than the preset deviation threshold, a position adjustment instruction is sent to the auxiliary inspection robot outside the tube. After receiving the position adjustment instruction, the auxiliary inspection robot outside the tube moves within a preset radius with the real-time position coordinates of the robot inside the tube as the center of the circle, and transmits an electromagnetic signal to the robot inside the tube at each moving point, so that the robot inside the tube repeats the step of calculating the target relative position coordinates based on the received electromagnetic signal until the target relative position coordinates meet the preset relative offset threshold.

[0029] Furthermore, before the electromagnetic signals transmitted by the auxiliary inspection robot outside the pipeline through the transmitter array are synchronously received by the multiple receivers carried by the in-pipeline robot, the method further includes:

[0030] The mobile positioning base station selects a stop position, continuously tracks satellite signals after moving to the stop position, and sends the satellite signals to the auxiliary inspection robot outside the pipe;

[0031] The auxiliary inspection robot outside the pipeline performs differential positioning calibration based on the satellite signal received from the mobile positioning base station, and after the differential positioning calibration, sends an electromagnetic signal to the robot inside the pipeline;

[0032] The process of selecting the location of the mobile positioning base station includes:

[0033] Determine the target operation section in which the robot in the tube is expected to operate;

[0034] Divide the projection of the target running section relative to the ground into multiple sections according to a preset interval, and obtain a two-dimensional coordinate lattice consisting of each segmentation node;

[0035] With the goal of minimizing the sum of the Euclidean distances from each point in the two-dimensional coordinate lattice to the target point, an optimization algorithm is used to solve the target point, and the target point is used as the stop position of the mobile positioning base station.

[0036] According to another aspect of the present invention, there is provided a robot positioning system for trenchless deep-buried pipelines, comprising:

[0037] The system includes an in-pipe robot and an auxiliary inspection robot outside the pipe, and the in-pipe robot performs in-pipe positioning according to the electromagnetic signal sent by the auxiliary inspection robot outside the pipe;

[0038] The in-pipe robot is used to synchronously receive the electromagnetic signals sent by the out-pipe auxiliary inspection robot through the transmitter array through the multiple receivers it carries; calculate the relative position coordinates of the in-pipe robot and the out-pipe auxiliary inspection robot based on the reception time of all electromagnetic signals received by different receivers to obtain the target relative position coordinates; when the target relative position coordinates meet the preset relative offset threshold, calculate the out-pipe auxiliary positioning coordinates based on the target relative position coordinates, and perform weighted average calculation based on the out-pipe auxiliary positioning coordinates and the real-time in-pipe positioning coordinates collected by different positioning sensor groups to obtain the target in-pipe positioning coordinates.

[0039] By means of the above technical solution, the technical solution provided by the embodiment of the present invention has at least the following advantages:

[0040] The present invention provides a method and system for positioning an in-pipe robot suitable for trenchless deep-buried pipelines. In an embodiment of the present invention, multiple receivers carried by the in-pipe robot synchronously receive electromagnetic signals transmitted by an external auxiliary inspection robot via a transmitter array. The relative position coordinates of the in-pipe robot and the external auxiliary inspection robot are calculated based on the reception time of all electromagnetic signals received by the different receivers to obtain the target relative position coordinates. When the target relative position coordinates meet a preset relative offset threshold, the external auxiliary positioning coordinates are calculated based on the target relative position coordinates. The target in-pipe positioning coordinates are obtained by performing a weighted average calculation based on the external auxiliary positioning coordinates and the real-time in-pipe positioning coordinates collected by different positioning sensor groups. The high-energy transmitter array is carried by the external auxiliary inspection robot, which ensures the endurance of the in-pipe robot while meeting the electromagnetic signal emission intensity. Furthermore, the accuracy of the in-pipe robot's positioning is ensured, thereby balancing the robot's endurance and signal detection intensity, and improving the in-pipe robot's applicability to different pipeline detection scenarios.

[0041] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0043] Figure 1 A flow chart of a method for positioning a robot in a trenchless deep-buried pipeline provided by an embodiment of the present invention is shown;

[0044] Figure 2 A flow chart of another in-pipe robot positioning method applicable to trenchless deep-buried pipelines provided by an embodiment of the present invention is shown;

[0045] Figure 3 The block diagram shows a composition of an in-pipe robot positioning system applicable to trenchless deep-buried pipelines provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0046] Exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided to enable a more thorough understanding of the present disclosure and to fully convey the scope of the present disclosure to those skilled in the art.

[0047] The problem of being unable to balance the robot's endurance and signal detection strength, resulting in low applicability to different pipeline detection scenarios. The embodiment of the present invention provides a method for positioning a robot in a trenchless deep-buried pipeline, such as Figure 1 As shown, the method includes:

[0048] 101. The robot inside the pipe synchronously receives the electromagnetic signals sent by the auxiliary inspection robot outside the pipe through the transmitter array through the multiple receivers it carries.

[0049] In an embodiment of the present invention, the pipeline in which the in-pipe robot operates is a trenchless deep-buried pipeline. The auxiliary inspection robot outside the pipe moving on the ground is equipped with a transmitter array, and the in-pipe robot moving in the pipe is equipped with a receiver. With the positioning information of the auxiliary inspection robot outside the pipe as the accurate position, the relative position between the auxiliary inspection robot outside the pipe and the robot inside the pipe is determined through the propagation of electromagnetic signals, thereby realizing the self-positioning of the robot inside the pipe. Specifically, in the process of the auxiliary inspection robot outside the pipe moving along the pre-loaded ground route, the electromagnetic signal is sent to the robot inside the pipe through the transmitter array, so that the robot inside the pipe calculates the relative coordinates between the auxiliary inspection robot outside the pipe and the robot inside the pipe based on the time difference when the electromagnetic signal is received by the receiver, thereby realizing its own positioning based on the relative coordinates and the real-time position of the auxiliary inspection robot outside the pipe. Among them, the ground route is the projection of the in-pipe route to the target defect point inside the pipe on the ground.

[0050] It should be noted that the transmitter array is an extremely low frequency (ELF) transmitter, meaning it emits electromagnetic waves in the frequency range of 3 Hz to 30 Hz. Continuous ELF transmission consumes a significant amount of power. By equipping the ground-based auxiliary inspection robots outside the pipeline with the transmitter array, the impact of transmission on the endurance of the robots inside the pipeline can be reduced. Furthermore, there's no need to use low-power transmission to avoid rapid battery consumption, thereby maintaining electromagnetic signal strength.

[0051] 102. Calculate the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe based on the reception time of all electromagnetic signals received by the different receivers to obtain the target relative position coordinates.

[0052] In this embodiment of the present invention, the in-pipeline robot is equipped with multiple receivers. Each receiver receives the same electromagnetic signal, the full electromagnetic signal transmitted by the auxiliary inspection robot outside the pipeline. The relative position coordinates of the in-pipeline robot and the auxiliary inspection robot outside the pipeline are calculated based on the reception time of the electromagnetic signal received by each receiver. Because there are multiple receivers, the target relative position coordinates are ultimately obtained.

[0053] 103. When the target relative position coordinates meet a preset relative offset threshold, calculate the auxiliary positioning coordinates outside the tube according to the target relative position coordinates.

[0054] In an embodiment of the present invention, after calculating the target relative position coordinates, it is necessary to determine whether the relative distance between the in-pipe robot and the auxiliary inspection robot outside the pipe represented by the target relative position coordinates meets the preset relative offset threshold. If the relative distance is less than or equal to the preset relative offset threshold, the target relative position coordinates are deemed to meet the preset relative offset threshold; if the relative distance is greater than the preset relative offset threshold, indicating that the offset between the in-pipe robot and the auxiliary inspection robot outside the pipe is large, the preset relative offset threshold is not met. Through the above judgment based on the preset relative offset threshold, it can be ensured that the distance and connection angle between the auxiliary inspection robot and the in-pipe robot will not be too large, thereby ensuring the accuracy of the relative position coordinates determined by the electromagnetic signal, and further ensuring the accuracy of the positioning of the in-pipe robot.

[0055] 104. Perform weighted average calculation based on the auxiliary positioning coordinates outside the pipe and the real-time positioning coordinates inside the pipe collected by different positioning sensor groups to obtain the target positioning coordinates inside the pipe.

[0056] In an embodiment of the present invention, different positioning sensor groups may include different types of positioning sensor groups such as odometer wheel sensors and inertial sensors, and each type of positioning sensor group is not limited to one. The positioning sensor group also continuously collects the real-time in-tube positioning coordinates of the in-tube machine during the movement of the in-tube robot. According to the weights corresponding to different positioning coordinates, the weighted average calculation is performed on the auxiliary positioning coordinates outside the tube and the real-time in-tube positioning coordinates collected by different positioning sensor groups, and the multi-dimensional positioning coordinates are fused as the final positioning coordinates of the in-tube robot, that is, the target in-tube positioning coordinates. By fusing the positioning coordinates of multiple sensors, the accuracy of the positioning data can be further improved. Calibrating the odometer with the target in-tube positioning coordinates can ensure that the in-tube robot performs the travel task based on the most accurate in-tube positioning coordinates, thereby reaching the target defect point in the tube.

[0057] In one embodiment of the present invention, for further explanation and limitation, as Figure 2 As shown, the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe are calculated based on the reception time of all electromagnetic signals received by different receivers to obtain the target relative position coordinates, including:

[0058] 201. For each receiver, the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe are calculated based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter arrays, and multiple groups of initial relative position coordinates determined according to the electromagnetic signals emitted by different transmitter arrays under each receiver are obtained.

[0059] 202. Convert all the initial relative position coordinates into the same coordinate system, and perform least squares processing on the multiple sets of initial relative position coordinates after the coordinate conversion to obtain target relative position coordinates.

[0060] In an embodiment of the present invention, each receiver synchronously receives electromagnetic signals synchronously transmitted by multiple groups of transmitter arrays. Different receivers receive electromagnetic signals emitted by all transmitter arrays, that is, different receivers receive electromagnetic signals from the same transmitter array. Since each group of transmitter arrays includes multiple transmitters distributed at preset intervals, each transmitter synchronously sends electromagnetic signals to the receiver. Through the reception time difference between each transmitter, a set of corresponding relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe, that is, the initial relative position coordinates, can be calculated. For the electromagnetic signals of the multiple groups of transmitter arrays received by each receiver, multiple groups of initial relative position coordinates can be calculated. For example, if the number of transmitter array groups is a and the number of receivers is b, then the electromagnetic signals of different transmitter array groups under different receivers can be calculated ( ) initial relative position coordinates. The initial relative position coordinates obtained above are unified into a coordinate system and processed by the least squares method to obtain the target relative position coordinates. The calculation formula of the target relative position coordinates is expressed as:

[0061]

[0062] in, Indicates the total number of initial relative position coordinates, Indicates the The relative coordinate value of the initial relative position coordinate in the horizontal direction, Indicates the The initial relative position coordinates are relative coordinate values ​​in the vertical direction, Indicates the The relative coordinate values ​​of the initial relative position coordinates in the depth direction.

[0063] In one embodiment of the present invention, for further explanation and limitation, the calculation of the relative position coordinates of the in-pipeline robot and the auxiliary inspection robot outside the pipe based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter array includes:

[0064] Calculating the reception time difference of each of the peripheral transmitters relative to the central transmitter;

[0065] Constructing a surface equation based on the reception time difference of each peripheral transmitter, the relative distance of the peripheral transmitter to the central transmitter, the electromagnetic wave propagation velocity in the soil, and the relative position coordinate variables corresponding to the transmitter array to obtain a surface equation between each peripheral transmitter and the receiver;

[0066] With the goal of minimizing the sum of squared errors between each surface equation and the approximate intersection point, the relative position coordinate variables in the surface equation are approximately solved using the least squares method to obtain the initial relative position coordinates determined based on the electromagnetic signal emitted by the transmitter array.

[0067] In this embodiment of the present invention, the transmitter array includes a central transmitter and multiple peripheral transmitters. Each transmitter in the array transmits only one electromagnetic signal with a corresponding timestamp, with the timestamp being referenced to the central transmitter (transmitter 0) as zero. The receiver of the robot inside the tube receives the electromagnetic signals and, based on the signal time differences and timestamps between the different electromagnetic signals, calculates the distance difference between them and establishes a surface equation. For example, for a transmitter array consisting of four transmitters (one central transmitter and three peripheral transmitters), the surface equation is expressed as:

[0068] ;

[0069] ;

[0070] ;

[0071] in, is the relative coordinate of the transmitter to transmitter No. 0; are the receiving time of the corresponding transmitter signal relative to the signal of transmitter No. 0, with a negative value for the signal that lags behind No. 0 and a negative value for the signal that leads No. 0; is the propagation velocity of electromagnetic waves in soil; 、 、 It represents the relative position coordinate variable of the robot inside the pipe to the auxiliary inspection robot outside the pipe that needs to be obtained.

[0072] is the electromagnetic wave propagation velocity in the soil and can be measured before the operation begins. However, due to measurement errors, the surfaces represented by the three equations may not intersect at a single point. Therefore, the surface equations are approximated using the least squares method. Specifically, removing the square root of the surface equations above yields the following error function:

[0073]

[0074] in, 、 、 The error of the code corresponding to the surface equation. Then, with the goal of minimizing the sum of squared errors, it is transformed into an optimization problem, and the following formula is obtained:

[0075] ;

[0076] At this point, numerical optimization methods such as scipy, optimize, and least_squares can be used to solve the problem. The optimal solution for the relative position coordinate variables is the initial relative position coordinates. It should be noted that the above method calculates a set of initial relative position coordinates based on the electromagnetic signals received by any receiver from any set of transmitter arrays. Because the auxiliary inspection robot outside the pipeline is equipped with multiple transmitter arrays and the robot inside the pipeline is equipped with multiple receivers, multiple sets of initial relative position coordinates can be obtained using the above method.

[0077] In one embodiment of the present invention, for further explanation and limitation, the weighted average calculation based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the target positioning coordinates inside the tube includes:

[0078] Retrieving weights corresponding to the odometer sensor group, the inertial sensor group, and the receiver respectively;

[0079] The target in-pipe positioning coordinates are obtained by performing a weighted average calculation based on the real-time in-pipe positioning coordinates collected by different positioning sensor groups and their corresponding weights, as well as the auxiliary positioning coordinates outside the pipe and the weights corresponding to the receivers.

[0080] In an embodiment of the present invention, in addition to the auxiliary positioning coordinates outside the pipe calculated based on the electromagnetic signals emitted by the auxiliary inspection robot outside the pipe, the robot inside the pipe is also equipped with different types of positioning sensor groups, which will also collect the positioning coordinates inside the pipe, that is, the real-time positioning coordinates inside the pipe. In order to improve the positioning accuracy, the auxiliary positioning coordinates outside the pipe are used as the inside pipe positioning coordinates collected by a positioning sensor group, and the weighted average calculation is performed with the real-time inside pipe positioning coordinates collected by other positioning sensor groups, and the calculation result is used as the positioning data of the robot inside the pipe, that is, the target inside pipe positioning coordinates. Among them, the positioning sensor group specifically includes but is not limited to the odometer wheel sensor group and the inertial sensor group. Among them, the initial weights corresponding to different positioning sensor groups can be obtained by experiments before the robot inside the pipe operates. The weighted average calculation formula is expressed as:

[0081] ;

[0082] in, 、 、 Respectively represent the target tube positioning coordinates in the horizontal, vertical and depth directions; 、 、 Respectively represent the weights of any type of positioning sensor or receiver in the corresponding direction, Indicates any type of positioning sensor or receiver; Indicates the group number of positioning sensor groups (the receiver is also considered as a group of positioning sensor groups).

[0083] In one embodiment of the present invention, to further illustrate and limit the embodiment of the present invention, after performing weighted average calculation based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the target positioning coordinates inside the tube, the method further includes:

[0084] During the process of the in-tube robot moving along the moving trajectory determined by the target in-tube positioning coordinates, the robot continuously calculates the auxiliary positioning coordinates outside the tube, and collects the in-tube positioning coordinates in real time through the different types of positioning sensor groups carried by the robot;

[0085] When the travel distance reaches a preset distance, the historical external auxiliary positioning coordinates and historical internal positioning coordinates within the preset distance are obtained, as well as the real-time external auxiliary positioning coordinates and real-time internal positioning coordinates;

[0086] For each type of positioning sensor group, a weight update calculation is performed based on the historical in-tube positioning coordinate data, the real-time in-tube positioning coordinates, and the corresponding weights to obtain a first target update weight;

[0087] Performing a weight update calculation based on the real-time off-pipeline auxiliary positioning coordinates, the historical off-pipeline auxiliary positioning coordinates, and the weight of the corresponding receiver to obtain a second target update weight;

[0088] The weights corresponding to the different types of positioning sensor groups in the weighted average calculation process are updated using the first target update weight, and the weights corresponding to the receivers are updated using the second target update weight.

[0089] In an embodiment of the present invention, in order to further improve the accuracy of the target in-tube positioning coordinate calculation. After performing weighted average calculation based on the weight, it is also necessary to update the weight based on the historical out-of-tube auxiliary positioning coordinates and historical in-tube positioning coordinate data produced during this period, and the real-time out-of-tube auxiliary positioning coordinates and real-time in-tube positioning coordinates after the in-tube robot travels a preset distance. The first update is to update the preset weights, and subsequent updates are to update the weights of the last update. The weight update process is to update different weights separately. The update weights that match each type of positioning sensor group are expressed as the first target update weights. The update weights that match the out-of-tube auxiliary positioning coordinates are expressed as the second target update weights. The weight update calculation method for the first target update weight and the second target update weight is the same.

[0090] In one embodiment of the present invention, for further explanation and limitation, for each type of positioning sensor group, a weight update calculation is performed based on the historical in-pipe positioning coordinate data, the real-time in-pipe positioning coordinates, and the corresponding weights to obtain a first target update weight, including:

[0091] Calculating the mean and variance of the historical in-tube positioning coordinate data, and the difference between the real-time in-tube positioning coordinates and the target in-tube positioning coordinates;

[0092] A weight correction coefficient is calculated according to the mean, the variance and the difference, and the product of the weight correction coefficient and the weight in the weighted average calculation process is used as the updated weight.

[0093] In the embodiment of the present invention, the overall formula for weight update calculation is expressed as:

[0094] ;

[0095] ;

[0096] ;

[0097] in, Indicates the difference between the real-time in-tube positioning coordinates of the corresponding positioning sensor group and the target in-tube positioning coordinates in different coordinate directions; 、 、 is a set of weights before updating; 、 、 The updated set of weights; 、 、 It represents the overall mean of the difference between each coordinate in the historical tube positioning coordinate and the target tube positioning coordinate. 、 、 Represents the overall variance of the difference between each coordinate in the historical tube positioning coordinates and the target tube positioning coordinates; 、 、 Represents a set of weight correction coefficients. Wherein, how long is the preset distance and how many times data needs to be collected during this period can be customized according to actual application requirements and are not specifically limited in the embodiment of the present invention.

[0098] After obtaining each set of weights, the updated weights may not sum to 1. Therefore, the weights need to be normalized to obtain the first target update weight. The normalization formula for the first target update weight is:

[0099]

[0100]

[0101]

[0102] in, 、 、 Indicates the first target update weight corresponding to any type of positioning sensor group.

[0103] In one embodiment of the present invention, for further explanation and limitation, when the target relative position coordinates do not meet the preset relative offset threshold, the method further includes:

[0104] The robot inside the pipe stops moving and sends calibration instructions to the auxiliary inspection robot outside the pipe;

[0105] The auxiliary inspection robot outside the pipe moves to a preset range above the robot inside the pipe according to the projection route of the path inside the pipe on the ground and the positioning coordinates inside the target pipe, and transmits an electromagnetic signal to the robot inside the pipe.

[0106] In embodiments of the present invention, the off-pipeline auxiliary inspection robot can move intermittently, stopping after reaching a certain position and then resuming movement upon receiving a calibration command. If the target relative position coordinates do not meet a preset relative offset threshold, this indicates that the distance between the off-pipeline auxiliary inspection robot and the robot inside the pipeline is too great, affecting the accuracy of electromagnetic signal positioning. To ensure accuracy, the robot inside the pipeline must stop and, via an onboard ELF transmitter (used only for sending calibration commands), send a calibration command to the off-pipeline auxiliary inspection robot. This calibration command carries the target on-pipeline positioning coordinates. After receiving the position of the robot inside the pipeline, the off-pipeline auxiliary inspection robot moves to a preset range above the robot inside the pipeline based on its relative position to the robot inside the pipeline and the projection of the pipeline path on the ground. The preset range can be relatively small to ensure that the off-pipeline auxiliary inspection robot is as close to the robot inside the pipeline as possible. The specific value can be customized based on the application scenario and is not specifically limited in embodiments of the present invention.

[0107] In one embodiment of the present invention, for further illustration and limitation, the method further includes:

[0108] Obtain the odometer positioning coordinates from the odometer carried by the in-tube robot;

[0109] When the difference between the odometer positioning coordinates and the auxiliary positioning coordinates outside the tube is greater than the preset deviation threshold, a position adjustment instruction is sent to the auxiliary inspection robot outside the tube. After receiving the position adjustment instruction, the auxiliary inspection robot outside the tube moves within a preset radius with the real-time position coordinates of the robot inside the tube as the center of the circle, and transmits an electromagnetic signal to the robot inside the tube at each moving point, so that the robot inside the tube repeats the step of calculating the target relative position coordinates based on the received electromagnetic signal until the target relative position coordinates meet the preset relative offset threshold.

[0110] In an embodiment of the present invention, the odometer is calibrated based on the target in-pipe positioning coordinates, but when the relative position between the in-pipe robot and the auxiliary inspection robot outside the pipe is inappropriate, a large deviation will appear between the positioning coordinates output by the odometer and the auxiliary positioning coordinates outside the pipe. Since the running path of the in-pipe robot is limited to the pipeline path, when the difference between the odometer positioning coordinates and the auxiliary positioning coordinates outside the pipe is greater than the preset deviation threshold, a position adjustment instruction is sent to the auxiliary inspection robot outside the pipe to adjust the position of the auxiliary inspection robot outside the pipe. The specific adjustment method is: when the in-pipe robot detects that the difference is greater than the preset deviation threshold, a position adjustment instruction is sent to the auxiliary inspection robot outside the pipe. After receiving the instruction, the auxiliary inspection robot outside the pipe changes its position multiple times in a circular area with the ground as the center above the received coordinates of the in-pipe robot, and transmits an electromagnetic signal to the in-pipe robot at each moving point, so that the in-pipe robot repeats the step of calculating the target relative position coordinates based on the received electromagnetic signal until the target relative position coordinates meet the preset relative offset threshold.

[0111] In one embodiment of the present invention, for further explanation and limitation, before the electromagnetic signals transmitted by the auxiliary inspection robot outside the pipeline through the transmitter array are synchronously received by the multiple receivers carried by the in-pipeline robot, the method further includes:

[0112] The mobile positioning base station selects a stop position, continuously tracks satellite signals after moving to the stop position, and sends the satellite signals to the auxiliary inspection robot outside the pipe;

[0113] The auxiliary inspection robot outside the pipe performs differential positioning calibration based on the satellite signal received from the mobile positioning base station, and after the differential positioning calibration, sends an electromagnetic signal to the robot inside the pipe.

[0114] In an embodiment of the present invention, the auxiliary inspection robot outside the pipe is based on satellite positioning of the mobile positioning base station. The auxiliary inspection robot outside the pipe needs to perform differential positioning calibration based on the satellite signals received by the mobile positioning base station, and after the differential positioning calibration, send electromagnetic signals to the robot inside the pipe. This requires the mobile positioning base station to select a suitable position to ensure the strength of the satellite signal and the accuracy of the satellite positioning data transmission. The position selection process of the mobile positioning base station includes: determining the target operation section in which the robot inside the pipe is expected to operate; dividing the projection of the target operation section relative to the ground into multiple sections according to the preset spacing, and obtaining a two-dimensional coordinate lattice composed of each segmentation node. The goal is to minimize the sum of the Euclidean distances from each point in the two-dimensional coordinate lattice to the target point, and use the optimization algorithm to solve the target point, and use the target point as the stop position of the mobile positioning base station. Let the optimal point be , there are N points in the two-dimensional coordinate matrix, and the sum of their Euclidean distances to all points is expressed as:

[0115] ;

[0116] in, Represents the sum of the Euclidean distances of all points in the two-dimensional coordinate lattice to the optimal point, ( , ) represents the coordinates of the i-th point in the two-dimensional coordinate matrix. The above formula is calculated by the optimization algorithm Minimum The value of is used to obtain the location of the mobile positioning base station.

[0117] The present invention provides a method for positioning an in-pipe robot suitable for trenchless deep-buried pipelines. In an embodiment of the present invention, multiple receivers carried by the in-pipe robot synchronously receive electromagnetic signals transmitted by an external auxiliary inspection robot via a transmitter array. The relative position coordinates of the in-pipe robot and the external auxiliary inspection robot are calculated based on the reception time of all electromagnetic signals received by the different receivers to obtain target relative position coordinates. When the target relative position coordinates meet a preset relative offset threshold, the external auxiliary positioning coordinates are calculated based on the target relative position coordinates. A weighted average calculation is performed based on the external auxiliary positioning coordinates and the real-time in-pipe positioning coordinates collected by different positioning sensor groups to obtain the target in-pipe positioning coordinates. The high-energy transmitter array is carried by the external auxiliary inspection robot. This ensures the endurance of the in-pipe robot while meeting the emission intensity of the electromagnetic signal. Furthermore, the accuracy of the in-pipe robot's positioning is ensured, thereby balancing the robot's endurance with signal detection intensity and improving the applicability of the in-pipe robot to different pipeline detection scenarios.

[0118] Furthermore, as a response to the above Figure 1 The embodiment of the present invention provides a robot positioning system for deep buried pipelines without excavation, such as Figure 3 As shown, the system includes: an in-pipe robot 31 and an auxiliary inspection robot 32 outside the pipe. The in-pipe robot 31 performs in-pipe positioning according to the electromagnetic signal sent by the auxiliary inspection robot 32 outside the pipe.

[0119] The in-pipe robot 31 is used to synchronously receive the electromagnetic signals sent by the out-pipe auxiliary inspection robot through the transmitter array through the multiple receivers it carries; calculate the relative position coordinates of the in-pipe robot and the out-pipe auxiliary inspection robot 32 based on the reception time of all electromagnetic signals received by different receivers to obtain the target relative position coordinates; when the target relative position coordinates meet the preset relative offset threshold, calculate the out-pipe auxiliary positioning coordinates based on the target relative position coordinates, and perform weighted average calculation based on the out-pipe auxiliary positioning coordinates and the real-time in-pipe positioning coordinates collected by different positioning sensor groups to obtain the target in-pipe positioning coordinates.

[0120] Furthermore, the in-pipe robot 31 is further configured to calculate the relative position coordinates of the in-pipe robot 31 and the auxiliary inspection robot outside the pipe based on the reception time of all electromagnetic signals received by the different receivers to obtain the target relative position coordinates, including:

[0121] For each receiver, the relative position coordinates of the in-pipeline robot 31 and the auxiliary inspection robot 32 outside the pipe are calculated based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter arrays, and multiple groups of initial relative position coordinates determined by the electromagnetic signals emitted by different transmitter arrays at each receiver are obtained;

[0122] All of the initial relative position coordinates are converted to the same coordinate system, and the multiple sets of initial relative position coordinates after the coordinate conversion are processed by least square method to obtain the target relative position coordinates.

[0123] Furthermore, the in-tube robot 31 is specifically used to calculate the reception time difference of each of the peripheral transmitters relative to the central transmitter;

[0124] Constructing a surface equation based on the reception time difference of each peripheral transmitter, the relative distance of the peripheral transmitter to the central transmitter, the electromagnetic wave propagation velocity in the soil, and the relative position coordinate variables corresponding to the transmitter array to obtain a surface equation between each peripheral transmitter and the receiver;

[0125] With the goal of minimizing the sum of squared errors between each surface equation and the approximate intersection point, the relative position coordinate variables in the surface equation are approximately solved using the least squares method to obtain the initial relative position coordinates determined based on the electromagnetic signal emitted by the transmitter array.

[0126] Furthermore, the in-tube robot 31 is further used to retrieve the weights corresponding to the odometer sensor group, the inertial sensor group and the receiver respectively;

[0127] The target in-pipe positioning coordinates are obtained by performing a weighted average calculation based on the real-time in-pipe positioning coordinates collected by different positioning sensor groups and their corresponding weights, as well as the auxiliary positioning coordinates outside the pipe and the weights corresponding to the receivers.

[0128] Furthermore, the in-tube robot 31 is further configured to continuously calculate auxiliary positioning coordinates outside the tube while the in-tube robot 31 is moving along a moving trajectory determined according to the target in-tube positioning coordinates, and to collect the in-tube positioning coordinates in real time through different types of positioning sensor groups carried thereon;

[0129] When the travel distance reaches a preset distance, the historical external auxiliary positioning coordinates and historical internal positioning coordinates within the preset distance are obtained, as well as the real-time external auxiliary positioning coordinates and real-time internal positioning coordinates;

[0130] For each type of positioning sensor group, a weight update calculation is performed based on the historical in-tube positioning coordinate data, the real-time in-tube positioning coordinates, and the corresponding weights to obtain a first target update weight;

[0131] Performing a weight update calculation based on the real-time off-pipeline auxiliary positioning coordinates, the historical off-pipeline auxiliary positioning coordinates, and the weight of the corresponding receiver to obtain a second target update weight;

[0132] The weights corresponding to the different types of positioning sensor groups in the weighted average calculation process are updated using the first target update weight, and the weights corresponding to the receivers are updated using the second target update weight.

[0133] Furthermore, the in-tube robot 31 is further configured to calculate the mean and variance of the historical in-tube positioning coordinate data, and the difference between the real-time in-tube positioning coordinates and the target in-tube positioning coordinates;

[0134] A weight correction coefficient is calculated according to the mean, the variance and the difference, and the product of the weight correction coefficient and the weight in the weighted average calculation process is used as the updated weight.

[0135] Furthermore, the in-pipe robot 31 is further configured to send a calibration instruction to the auxiliary inspection robot 32 outside the pipe when the target relative position coordinates do not meet a preset relative offset threshold, wherein the calibration instruction carries the target in-pipe positioning coordinates;

[0136] The auxiliary inspection robot 32 outside the pipe is used to move to a preset range above the robot 31 inside the pipe according to the projection route of the path inside the pipe on the ground and the positioning coordinates inside the target pipe, and transmit electromagnetic signals to the robot 31 inside the pipe.

[0137] Furthermore, the in-tube robot 31 is also used to obtain the odometer positioning coordinates from the odometer carried;

[0138] When the difference between the odometer positioning coordinates and the auxiliary positioning coordinates outside the pipeline is greater than a preset deviation threshold, a position adjustment instruction is sent to the auxiliary inspection robot outside the pipeline 32;

[0139] The auxiliary inspection robot 32 outside the pipe is also used to move within a preset radius with the real-time position coordinates of the robot 31 inside the pipe as the center of the circle after receiving the position adjustment instruction, and to transmit an electromagnetic signal to the robot 31 inside the pipe at each moving point, so that the robot 31 inside the pipe repeats the step of calculating the target relative position coordinates based on the received electromagnetic signal until the target relative position coordinates meet the preset relative offset threshold.

[0140] Furthermore, the system also includes a mobile positioning base station,

[0141] The mobile positioning base station is used to select a stop position, continuously track satellite signals after moving to the stop position, and send the satellite signals to the auxiliary inspection robot 32 outside the pipeline;

[0142] The auxiliary inspection robot 32 outside the pipe is further used to perform differential positioning calibration based on the satellite signals received from the mobile positioning base station, and after the differential positioning calibration, send an electromagnetic signal to the robot 31 inside the pipe;

[0143] The process of selecting the location of the mobile positioning base station includes:

[0144] Determine a target operation section in which the in-tube robot 31 is expected to operate;

[0145] Divide the projection of the target running section relative to the ground into multiple sections according to a preset interval, and obtain a two-dimensional coordinate lattice consisting of each segmentation node;

[0146] With the goal of minimizing the sum of the Euclidean distances from each point in the two-dimensional coordinate lattice to the target point, an optimization algorithm is used to solve the target point, and the target point is used as the stop position of the mobile positioning base station.

[0147] The present invention provides an in-pipe robot positioning system suitable for trenchless deep-buried pipelines. In an embodiment of the present invention, multiple receivers carried by the in-pipe robot synchronously receive electromagnetic signals transmitted by the external auxiliary inspection robot via a transmitter array. The relative position coordinates of the in-pipe robot and the external auxiliary inspection robot are calculated based on the reception time of all electromagnetic signals received by the different receivers to obtain the target relative position coordinates. When the target relative position coordinates meet a preset relative offset threshold, the external auxiliary positioning coordinates are calculated based on the target relative position coordinates. The target in-pipe positioning coordinates are obtained by performing a weighted average calculation based on the external auxiliary positioning coordinates and the real-time in-pipe positioning coordinates collected by different positioning sensor groups. The high-energy transmitter array is carried by the external auxiliary inspection robot. This ensures the endurance of the in-pipe robot while meeting the electromagnetic signal emission intensity requirements. Furthermore, the accuracy of the in-pipe robot positioning is ensured, thereby balancing the robot's endurance with signal detection intensity and improving the applicability of the in-pipe robot to different pipeline detection scenarios.

[0148] Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented using a general-purpose computing system. They can be centralized on a single computing system or distributed across a network of multiple computing systems. Alternatively, they can be implemented using program code executable by a computing system, and thus, they can be stored in a storage system and executed by the computing system. In some cases, the steps shown or described herein can be performed in a different order than that shown, or they can be fabricated into separate integrated circuit modules, or multiple modules or steps can be fabricated into a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0149] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A method for positioning a robot inside a trenchless deep-buried pipeline, characterized in that: The robot inside the pipe performs positioning inside the pipe based on the electromagnetic signal sent by the auxiliary inspection robot outside the pipe, and the method includes: The electromagnetic signals sent by the auxiliary inspection robot outside the pipe through the transmitter array are synchronously received by the multiple receivers carried by the robot inside the pipe; Calculating the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe according to the reception time of all electromagnetic signals received by different receivers to obtain the relative position coordinates of the target; When the target relative position coordinates meet a preset relative offset threshold, calculating the auxiliary positioning coordinates outside the tube according to the target relative position coordinates; Performing weighted average calculation based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the target positioning coordinates inside the tube; During the process of the in-tube robot moving along the moving trajectory determined by the target in-tube positioning coordinates, the robot continuously calculates the auxiliary positioning coordinates outside the tube, and collects the in-tube positioning coordinates in real time through the different types of positioning sensor groups carried by the robot; When the travel distance reaches a preset distance, the historical external auxiliary positioning coordinates and historical internal positioning coordinates within the preset distance are obtained, as well as the real-time external auxiliary positioning coordinates and real-time internal positioning coordinates; For each type of positioning sensor group, a weight update calculation is performed based on the historical in-tube positioning coordinate data, the real-time in-tube positioning coordinates, and the corresponding weights to obtain a first target update weight; Performing a weight update calculation based on the real-time off-pipeline auxiliary positioning coordinates, the historical off-pipeline auxiliary positioning coordinates, and the weight of the corresponding receiver to obtain a second target update weight; The weights corresponding to the different types of positioning sensor groups in the weighted average calculation process are updated using the first target update weight, and the weights corresponding to the receivers are updated using the second target update weight.

2. The method according to claim 1, characterized in that Each of the receivers synchronously receives electromagnetic signals synchronously transmitted by a plurality of transmitter arrays, wherein each transmitter array comprises a plurality of transmitters distributed at a preset interval, and each transmitter synchronously transmits electromagnetic signals to the receiver; The method of calculating the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe based on the reception time of all electromagnetic signals received by the different receivers to obtain the target relative position coordinates includes: For each receiver, the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe are calculated based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter arrays, and multiple groups of initial relative position coordinates determined according to the electromagnetic signals emitted by different transmitter arrays under each receiver are obtained; All of the initial relative position coordinates are converted to the same coordinate system, and the multiple sets of initial relative position coordinates after the coordinate conversion are processed by least square method to obtain the target relative position coordinates.

3. The method according to claim 2, characterized in that The transmitter array includes a central transmitter and multiple peripheral transmitters. The calculation of the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe based on the reception time difference between the multiple electromagnetic signals received by each group of the transmitter array includes: Calculating the reception time difference of each of the peripheral transmitters relative to the central transmitter; Constructing a surface equation based on the reception time difference of each peripheral transmitter, the relative distance of the peripheral transmitter to the central transmitter, the electromagnetic wave propagation velocity in the soil, and the relative position coordinate variables corresponding to the transmitter array to obtain a surface equation between each peripheral transmitter and the receiver; With the goal of minimizing the sum of squared errors between each surface equation and the approximate intersection point, the relative position coordinate variables in the surface equation are approximately solved using the least squares method to obtain the initial relative position coordinates determined based on the electromagnetic signal emitted by the transmitter array.

4. The method according to claim 1, wherein The positioning sensor group includes an odometer sensor group and an inertial sensor group. The weighted average calculation is performed based on the auxiliary positioning coordinates outside the pipe and the real-time positioning coordinates inside the pipe collected by different positioning sensor groups to obtain the target positioning coordinates inside the pipe, including: Retrieving weights corresponding to the odometer sensor group, the inertial sensor group, and the receiver respectively; The target in-pipe positioning coordinates are obtained by performing a weighted average calculation based on the real-time in-pipe positioning coordinates collected by different positioning sensor groups and their corresponding weights, as well as the auxiliary positioning coordinates outside the pipe and the weights corresponding to the receivers.

5. The method according to claim 1, wherein For each type of positioning sensor group, performing weight update calculation based on the historical in-pipe positioning coordinate data, the real-time in-pipe positioning coordinates, and corresponding weights to obtain a first target update weight includes: Calculating the mean and variance of the historical in-tube positioning coordinate data, and the difference between the real-time in-tube positioning coordinates and the target in-tube positioning coordinates; A weight correction coefficient is calculated according to the mean, the variance and the difference, and the product of the weight correction coefficient and the weight in the weighted average calculation process is used as the updated weight.

6. The method according to claim 1, wherein When the target relative position coordinates do not meet a preset relative offset threshold, the method further includes: The robot inside the pipe stops moving and sends a calibration instruction to the auxiliary inspection robot outside the pipe, wherein the calibration instruction carries the target positioning coordinates inside the pipe; The auxiliary inspection robot outside the pipe moves to a preset range above the robot inside the pipe according to the projection route of the path inside the pipe on the ground and the positioning coordinates inside the target pipe, and transmits an electromagnetic signal to the robot inside the pipe.

7. The method according to claim 1, characterized in that The method further comprises: Obtain the odometer positioning coordinates from the odometer carried by the in-tube robot; When the difference between the odometer positioning coordinates and the auxiliary positioning coordinates outside the pipeline is greater than a preset deviation threshold, a position adjustment instruction is sent to the auxiliary inspection robot outside the pipeline; After receiving the position adjustment instruction, the auxiliary inspection robot outside the pipe moves within a preset radius with the real-time position coordinates of the robot inside the pipe as the center of the circle, and transmits an electromagnetic signal to the robot inside the pipe at each moving point, so that the robot inside the pipe repeats the step of calculating the target relative position coordinates based on the received electromagnetic signal until the target relative position coordinates meet the preset relative offset threshold.

8. The method according to claim 1, characterized in that Before synchronously receiving, by the multiple receivers carried by the in-pipeline robot, the electromagnetic signal transmitted by the auxiliary inspection robot outside the pipe through the transmitter array, the method further comprises: The mobile positioning base station selects a stop position, continuously tracks satellite signals after moving to the stop position, and sends the satellite signals to the auxiliary inspection robot outside the pipe; The auxiliary inspection robot outside the pipeline performs differential positioning calibration based on the satellite signal received from the mobile positioning base station, and after the differential positioning calibration, sends an electromagnetic signal to the robot inside the pipeline; The process of selecting the location of the mobile positioning base station includes: Determine the target operation section in which the robot in the tube is expected to operate; Divide the projection of the target running section relative to the ground into multiple sections according to a preset interval, and obtain a two-dimensional coordinate lattice consisting of each segmentation node; With the goal of minimizing the sum of the Euclidean distances from each point in the two-dimensional coordinate lattice to the target point, an optimization algorithm is used to solve the target point, and the target point is used as the stop position of the mobile positioning base station.

9. A robot positioning system for trenchless deep-buried pipelines, characterized in that: The system includes an in-pipe robot and an auxiliary inspection robot outside the pipe, and the in-pipe robot performs in-pipe positioning according to the electromagnetic signal sent by the auxiliary inspection robot outside the pipe; The in-pipeline robot is used to synchronously receive, through the multiple receivers carried thereon, electromagnetic signals sent by the auxiliary inspection robot outside the pipe through the transmitter array; Calculating the relative position coordinates of the robot inside the pipe and the auxiliary inspection robot outside the pipe according to the reception time of all electromagnetic signals received by different receivers to obtain the relative position coordinates of the target; When the relative position coordinates of the target meet the preset relative offset threshold, the auxiliary positioning coordinates outside the tube are calculated according to the relative position coordinates of the target, and the weighted average calculation is performed based on the auxiliary positioning coordinates outside the tube and the real-time positioning coordinates inside the tube collected by different positioning sensor groups to obtain the positioning coordinates inside the tube of the target; The in-tube robot is further configured to continuously calculate auxiliary positioning coordinates outside the tube while moving along a moving trajectory determined by the target in-tube positioning coordinates, and to collect the in-tube positioning coordinates in real time through different types of positioning sensor groups carried thereon; When the travel distance reaches a preset distance, the historical external auxiliary positioning coordinates and historical internal positioning coordinates within the preset distance are obtained, as well as the real-time external auxiliary positioning coordinates and real-time internal positioning coordinates; For each type of positioning sensor group, a weight update calculation is performed based on the historical in-tube positioning coordinate data, the real-time in-tube positioning coordinates, and the corresponding weights to obtain a first target update weight; Performing a weight update calculation based on the real-time off-pipeline auxiliary positioning coordinates, the historical off-pipeline auxiliary positioning coordinates, and the weight of the corresponding receiver to obtain a second target update weight; The weights corresponding to the different types of positioning sensor groups in the weighted average calculation process are updated using the first target update weight, and the weights corresponding to the receivers are updated using the second target update weight.

Images