Shield machine posture measurement and guidance method without moving station

Abstract

The present invention discloses a shield machine posture measurement and guidance method without moving the station. By setting the prism position and performing periodic alternating measurement with a total station, the method solves the technical problems of high measurement cost and low reliability in the prior art. The method comprises the following steps: (1) setting a laser target; (2) staggering the prisms in front and back; (3) setting the total station on the supporting frame behind the shield machine; (4) setting the station for the first time; (5) observing the laser target with the total station; (6) setting the station again and judging whether the searched prism is correct; (7) observing according to the alternating observation method to complete the resetting of the station; (8) repeating steps (5) and (7) to guide the forward posture of the shield machine according to the measurement results of the laser target. The method has the advantages of low cost of the measurement and guidance device, simple layout operation and high reliability of the results.

Description

Technical Field

[0001] The present invention relates to the field of measurement technology, and in particular to a shield posture measurement and guidance method without station moving. Background Art

[0002] Tunnel shield excavation has gradually become the main means of urban underground engineering construction. During the forward advancement and turning process of the shield machine, the position information of the shield machine must be monitored at all times through the guidance system to determine the tunneling axis of the shield machine. By adjusting the tunneling posture of the shield machine, the tunneling axis is ensured to be as consistent as possible with the designed theoretical axis.

[0003] The existing technology mainly uses laser guidance system to manage the posture of shield machine, see Figure 1 It mainly consists of a total station, a laser target and a rearview prism. The total station is fixedly connected to the tunnel segments, and the laser target is fixedly connected to the shield of the shield machine. During the turning process, as the shield machine moves forward, the position of the total station remains unchanged, while the laser target fixed on the shield will move farther and farther away from the total station. After excavating a certain distance and angle, due to angle deviation or obstruction by the internal equipment of the shield machine, the laser target cannot capture the laser emitted by the total station. At this time, the total station needs to be moved forward. After the total station is moved, its position coordinates must be recalibrated, which is a complicated operation. If it is on a small radius curve, due to the small measurement window, the total station needs to be positioned as far forward as possible. However, since the newly assembled segments will float or rotate, the position of the total station will also change, causing the laser total station to exceed the coordinate error, requiring personnel to recalibrate its coordinates, and causing a certain positioning error.

[0004] The inventor is aware of a shield guide system (CN215057377U) that does not require station change. The guide system discloses that an automatic leveling base is fixed to the bottom of the total station, the total station is fixedly mounted on a trolley via the automatic leveling base, and a vertical mechanism is provided on the top of the rearview prism.

[0005] However, in the process of implementing the technical solutions in the embodiments of the present application, the inventors of the present application found that the above technology has at least the following technical problems: the equipment is complex and has low reliability; the rearview prism in the technical solution is a motor prism, which needs to be connected to the total station through a communication interface for control during measurement, which not only increases the cost but also increases the failure rate of the guidance system.

[0006] The information disclosed in this background technology section is only used to deepen the understanding of the background technology of the present disclosure and should not be regarded as an admission or any form of suggestion that the information constitutes the prior art known to those skilled in the art. Summary of the Invention

[0007] In view of at least one of the above technical problems, the present disclosure provides a shield posture measurement and guidance method without moving the station, which solves the technical problems of high measurement cost and low reliability in the existing technology through the setting of prism positions and periodic alternating measurement of the total station.

[0008] According to one aspect of the present disclosure, a shield machine posture measurement and guidance method without moving the station is provided, comprising the following steps:

[0009] (1) Place a laser target in the shield machine's measurement window and adjust the laser target so that its axis is parallel to the shield machine's axis;

[0010] (2) Fix prism 1 and prism 2 on the tunnel wall, and the prisms are staggered in front and back in the direction of shield advance;

[0011] (3) The total station is set on the supporting frame behind the shield machine through the automatic leveling base, and a shock-absorbing bolt is provided between the automatic leveling base and the total station;

[0012] (4) For the initial station setting, the total station is set up using the resection method. The total station is driven to observe the two prisms separately to obtain the distances S1 and S2 between the total station and the two prisms and the angle α;

[0013] (5) Drive the total station to observe the laser target and obtain the shield machine posture information;

[0014] (6) Set up the station again. The total station automatically searches for the two prisms based on the initial observation angle, and estimates the distance between the total station and the two prisms by the total station's forward distance L. =S1+L, =S2+L, according to the difference in distance between the total station and the two staggered prisms, determine whether the searched prism is correct. If the search is correct, repeat step (5), otherwise record the measurement information under the other prism, and estimate the distance S between the two prisms. and Angle , and drives the total station to rotate Angle to find another prism;

[0015] (7) Based on the last observed prism of the previous station setting, make three observations in the alternating observation method of prism 1-prism 2-prism 1 or prism 2-prism 1-prism 2. Perform average calculation on the prism information of repeated observations, and complete the station setting again based on the averaged result and the measurement information of another prism;

[0016] (8) Repeat steps (5) to (7) to guide the forward posture of the shield machine according to the measurement results of the laser target.

[0017] In some embodiments of the present disclosure, in step (2), the difference in front-to-back distance between the two prisms along the shield's advancing direction is 30-50 m.

[0018] In some embodiments of the present disclosure, in step (3), the total station is installed in a position that ensures that the field of view between it and the two prisms is clear and unobstructed.

[0019] In some embodiments of the present disclosure, in step (6), whether the searched prism is correct is determined by comparing the actual observed distance of the prism with the estimated distance. If the difference between the two is less than 0.02m, the search is considered correct.

[0020] In some embodiments of the present disclosure, in step (6), the angle .

[0021] In some embodiments of the present disclosure, in step (7), the averaging calculation includes calculating the average of two observed distance values and calculating the average of two observed azimuth angles.

[0022] In some embodiments of the present disclosure, in step (8), if the shield machine turns and there is no transparency between the total station and any prism, or when the total station has a prism search error for more than three consecutive times and it is confirmed that there is no obstruction between the total station and the prism, it is necessary to move the prism forward according to the deployment method described in step (2).

[0023] One or more technical solutions provided in the embodiments of this application have at least any of the following technical effects or advantages:

[0024] 1. Before re-setting the station, an estimated calculation is made based on the distance the total station has traveled along the shield machine, and the prisms are staggered in front and behind along the shield machine's direction of travel, providing a basis for judging the prism search results. This effectively solves the problems of cumbersome installation and wiring, tedious and complicated operations during movement, increased costs, and increased system failure rates caused by the use of motor prisms in the existing technology, thereby achieving the replacement of motor prisms with ordinary prisms, reducing construction costs while ensuring measurement guidance effects.

[0025] 2. The alternating measurement method was adopted to set up the station, and the dynamic process of the total station moving along with the shield machine was introduced. By averaging the first and last sets of measurement data of the same prism, the measurement error caused by the movement of the total station position was effectively reduced, thus ensuring the reliability of the measurement data.

[0026] 3. The total station and the automatic leveling base are connected with shock-absorbing bolts, which greatly reduces the impact of tunneling vibration on the stability of the total station. It solves the technical problem that the automatic leveling base can only be adjusted at a large tilt angle and cannot achieve shock absorption. It achieves the maintenance of a relatively stable state of the total station, thereby ensuring the continuity and stability of the guidance system. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 This is a schematic diagram of the structure of the existing shield attitude guidance system.

[0028] Figure 2 This is a flow chart of the shield posture free station guidance method in one embodiment of the present application.

[0029] Figure 3 This is a schematic diagram of the connection structure between the total station and the automatic leveling base in one embodiment of the present application.

[0030] Figure 4 Schematic diagram of the layout of the total station, prism and laser target in one embodiment of the present application.

[0031] Figure 5 Schematic diagram of prism layout and estimation algorithm in one embodiment of the present application.

[0032] In the above figures, 1 is the tunnel wall, 2 is the cutterhead of the shield machine, 3 is the rear-view prism, 31 is prism 1, 32 is prism 2, 4 is the total station, 40 is the moved total station, 5 is the laser target, 6 is the central control box, 7 is the industrial computer, 8 is the wireless transceiver module, 9 is the automatic leveling base, 10 is the shock-absorbing bolt, and 11 is the rear frame of the shield machine. DETAILED DESCRIPTION

[0033] In the description of this application, it should be understood that the terms "up", "down", "front", "back", "left", "right", "top", "bottom", "inside", "outside", "vertical", "horizontal", "clockwise", "counterclockwise", etc., indicating directions or positional relationships, are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device referred to must have a specific direction, and therefore cannot be understood as a limitation on this application.

[0034] The programs involved or relied upon in the following embodiments are all conventional or simple programs in the technical field, and those skilled in the art can make conventional selections or adaptive adjustments according to specific application scenarios.

[0035] Unless otherwise specified, the devices involved in the following embodiments are conventional commercially available products.

[0036] In order to better understand the technical solution of the present application, the above technical solution will be described in detail below with reference to the accompanying drawings and specific implementation methods.

[0037] This example discloses a shield posture measurement and guidance method without moving the station, see Figure 2 , including the following steps:

[0038] (1) Set the laser target in the shield machine measurement window and adjust the laser target so that its axis is parallel to the shield machine axis.

[0039] During the design and manufacture of a shield machine, a measurement window is reserved for measuring the shield machine's excavation posture. In this embodiment, a laser target is installed in the shield machine's measurement window, and the laser beam emitted by the total station is used to determine the shield machine's forward angle and distance. When installing the laser target, its axis needs to be adjusted to be roughly parallel to the shield machine's axis, with an inclination value of less than 1 degree. It is also necessary to ensure that the total station's incident angle when measuring the laser target remains within a reliable measurement range, with a lateral deviation of no more than 12 cm per meter and a slope of no more than 15 cm per meter. This avoids the problem of an excessively large incident angle causing an excessively large light spot, which in turn affects measurement accuracy.

[0040] (2) Prism 1 and prism 2 are fixed on the tunnel wall, and the prisms are staggered in front and back in the direction of shield advance.

[0041] In this embodiment, two prisms are used for station setup and measurement, and the total station uses corner intersection for station setup. The two prisms are mounted on either side of the tunnel wall, maximizing the angle between them and the total station to avoid measurement errors caused by a small angle that makes observation difficult for the total station. Each prism must be positioned so that it has a clear field of view with the total station to prevent other facilities or structures within the tunnel from interfering with the total station's observation of the prisms. The two prisms are conventional prisms, requiring no wiring or communication operations, effectively reducing installation workload and the incidence of failures. The two prisms can be directly bolted to the tunnel wall via corresponding frames. They are staggered in a front-to-back arrangement along the direction of travel of the shield machine, with a front-to-back distance difference of 30-50 meters. This allows the total station to accurately search for the prisms during operation. In this embodiment, the distance difference between the two prisms along the direction of travel of the shield machine is set to 40 meters.

[0042] In some other embodiments, three prisms are set in the tunnel to improve the measurement accuracy. The three prisms are staggered front and back along the forward direction of the shield machine. The front and back distance difference between any two adjacent prisms along the forward direction of the shield machine is 30-50m, and the angle between any two prisms and the total station is set to the maximum as much as possible to avoid measurement errors caused by the difficulty of observation of the total station due to the small angle. The layout position of each prism needs to be transparent to the field of view of the total station to avoid other facilities or structures in the inner tunnel affecting the observation of each prism by the total station.

[0043] (3) The total station is set on the supporting frame behind the shield machine through the automatic leveling base, and shock-absorbing bolts are provided between the automatic leveling base and the total station.

[0044] In order to avoid the complicated relocation operation caused by the multiple relocation of the total station fixed on the pipe wall, and the impact on the construction progress caused by the shield machine downtime caused by the comparison of the measurement results before and after the relocation of the total station, see Figure 3 Therefore, the total station is set on the supporting frame behind the shield machine, and it continues to move forward as the shield machine excavates, and it is necessary to ensure that the field of view between the total station and the prisms on the pipe wall is transparent. Figure 4 , to avoid the equipment on the frame blocking the observation line of sight. Since the frame is affected by the flatness when moving in the tunnel, it will tilt during the movement of the frame, which will cause the level bubble of the total station to move back and forth and fail to meet the working requirements. Therefore, an automatic leveling base is set between the total station and the frame to offset the tilt of the frame and ensure that the level bubble of the total station is always in the center. In addition, the automatic leveling base does not have a shock-absorbing effect. When the shield machine is excavating, the cutterhead cutting the rock will cause vibration. This vibration will be transmitted along the frame to the total station, causing measurement errors or even measurement failures. Therefore, shock-absorbing bolts are set between the total station and the automatic leveling base to reduce the impact of vibration on the stability of the total station during excavation.

[0045] (4) When setting up the station for the first time, the total station is set up using the rear intersection method. The total station is driven to observe the two prisms separately to obtain the distances S1 and S2 between the total station and the two prisms and the angle α.

[0046] Once the prisms, laser targets, and total station are installed and set up, measurement can begin. Initially, the coordinates of each prism's position are recorded in the total station based on the known points on the control network. The total station is then manually operated to perform a rough aiming operation on prisms one and two. The total station automatically searches for the prisms, obtaining the distance S1 from the total station to prism one, the distance S2 from the total station to prism two, and the angle α between the total station and the two prisms. The total station's resection function then automatically calculates the coordinates of the total station's position.

[0047] (5) Drive the total station to observe the laser target and obtain the shield machine posture information.

[0048] According to the coordinate position information of the total station in step (4), that is, the determined coordinate information of the total station is known, the total station is driven to observe the laser target, and the laser target position information such as the horizontal angle and the distance L are obtained, and then it is judged whether the actual forward posture of the shield machine is consistent with the designed forward curve, and corresponding adaptive adjustments are made.

[0049] (6) Set up the station again. The total station automatically searches for the two prisms based on the initial observation angle, and estimates the distance between the total station and the two prisms by the total station's forward distance L. =S1+L, =S2+L, according to the difference in distance between the total station and the two staggered prisms, determine whether the searched prism is correct. If the search is correct, repeat step (5), otherwise record the measurement information under the other prism, and estimate the distance S between the two prisms. and Angle , and drives the total station to rotate Angle to find another prism.

[0050] Since the total station is set on the supporting frame behind the shield machine, it will move forward with the shield machine, so the coordinate position of the total station will change. Therefore, it is impossible to observe the laser target based on the total station coordinate position information obtained during the initial station setting. The total station needs to be set up again to obtain the total station coordinate position information again, and the laser target is observed with the latest station setting data to obtain the forward posture information of the shield machine.

[0051] When setting up the station again, it is still necessary to observe the two prisms. However, due to the limitations of the shield machine's external environment or the long distance of advancement, the angle between the two prisms and the total station will be too small, resulting in the total station searching for the wrong target prism. Figure 5 In order to ensure the accuracy of the total station in searching for the target prism, it is necessary to estimate the position of the target prism. Since the total station moves with the shield machine and the moving distance is L, the distance between the total station and the two prisms after the movement is estimated. =S1+L, =S2+L, and use this as a basis to judge the correctness of the prism search.

[0052] Since the two prisms are staggered in front and back along the shield machine's forward direction, the difference in distance between the total station and the two staggered prisms is used to determine whether the searched prism is the target prism. The total station automatically rotates to the corresponding position based on the angle used when observing the prism at the initial station setting, and automatically searches for prisms near the position. After searching for the prism, it measures and compares the measured information with the corresponding estimated distance. If the difference between the measured distance and the estimated distance is less than 0.02m, it can be determined that the search is correct. Otherwise, the measurement information is recorded under the information of another prism different from the target prism, and the distance S between the two prisms is obtained from the known coordinates of the control network and estimated according to the cosine theorem. and Angle Using this angle as the search basis, the total station is driven to rotate the corresponding angle to search for the target prism. Because the two prisms are staggered in front and behind, and the distance difference is 30-50 meters, this large distance difference ensures the accuracy of the judgment, improves its reliability, avoids the use of complex prism devices, and reduces workload and error rate.

[0053] (7) Based on the last observed prism of the previous station setting, three observations are carried out according to the alternating observation method of prism 1-prism 2-prism 1 or prism 2-prism 1-prism 2. The prism information of the repeated observations is averaged and calculated. The station setting is completed again based on the averaged result and the measurement information of the other prism.

[0054] According to step (6), the two prisms can be re-measured. However, since the total station is not in a stationary state during the measurement of the two prisms, it moves forward with the shield machine. Therefore, in order to ensure the accuracy of the station setting, the alternating observation method is used for measurement. The observation is carried out in the order of prism 1-prism 2-prism 1 or prism 2-prism 1-prism 2. Since the first and last prisms are the same prism, the starting and ending position information of the dynamic process is introduced. The observation information of the same prism at the beginning and end is averaged, that is, the distance observation value and the horizontal angle observation value are averaged respectively. The averaged result and the measurement information of the other prism are used to complete the re-station setting with higher reliability.

[0055] In some other embodiments, three rear-view prisms are provided. When the alternating observation method is used for re-stationing, observations are performed in the order of prism one - prism two - prism three - prism one - prism two or prism three - prism one - prism two - prism three, and the average value of the prism information repeatedly measured at the beginning and end is taken to complete the re-stationing.

[0056] (8) Repeat steps (5) to (7) to guide the forward posture of the shield machine according to the measurement results of the laser target.

[0057] Once the station is set up again, the laser target can be observed using this station information to guide the shield machine's posture adjustments. However, if the shield machine's long excavation distance results in a small angle between the total station and the prisms, making rearview difficult, or if the total station cannot observe the rearview prisms due to the shield machine's turns on a curved route, the positions of the prisms need to be adjusted, moving them forward while maintaining the same staggered arrangement and distance. This allows for low-cost, highly reliable measurement and guidance of the shield machine's forward posture.

[0058] Although some preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention.

[0059] Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if such changes and modifications of the present invention fall within the scope of the claims and their equivalents, the present invention is intended to include such changes and modifications.

Claims

1. A shield posture measurement and guidance method without moving the station, characterized in that: The steps include: (1) Place a laser target in the shield machine's measurement window and adjust the laser target so that its axis is parallel to the shield machine's axis; (2) Fix prism 1 and prism 2 on the tunnel wall, and the prisms are staggered in front and back in the direction of shield advance; (3) The total station is set on the supporting frame behind the shield machine through the automatic leveling base, and a shock-absorbing bolt is provided between the automatic leveling base and the total station; (4) For the initial station setting, the total station is set up using the resection method. The total station is driven to observe the two prisms respectively to obtain the distances S1 and S2 between the total station and the two prisms and the angle α between the total station and the two prisms. (5) Drive the total station to observe the laser target and obtain the shield machine posture information; (6) Set up the station again. The total station automatically searches for the two prisms based on the initial observation angle of the station, and estimates the distance between the total station and the two prisms S1'=S1+L and S2'=S2+L based on the total station's forward distance L. According to the difference in the distance between the total station and the two staggered prisms, it is judged whether the searched prism is correct. If the search is correct, repeat step (5). Otherwise, this measurement information is recorded under another prism, and according to the distance S between the two prisms, the angle α' between S1' and S2' is estimated, and the total station is driven to rotate the angle α' to find another prism. (7) Based on the last observed prism of the previous station setting, make three observations in the alternating observation method of prism 1-prism 2-prism 1 or prism 2-prism 1-prism 2. Perform average calculation on the prism information of repeated observations, and complete the station setting again based on the averaged result and the measurement information of another prism; (8) Repeat steps (5) to (7) to guide the forward posture of the shield machine according to the measurement results of the laser target.

2. The shield posture measurement and guidance method without moving the station according to claim 1 is characterized in that: In step (2), the difference in front-to-back distance between the two prisms along the shield's forward direction is 30-50m.

3. The shield posture measurement and guidance method without moving the station according to claim 1 is characterized in that: In step (3), the total station is installed in a position that ensures that the field of view between it and the two prisms is clear and unobstructed.

4. The shield posture measurement and guidance method without moving the station according to claim 1 is characterized in that: In step (6), whether the searched prism is correct is determined by comparing the actual observation distance of the prism with the estimated distance S1' / S2'. If the difference between the two is less than 0.02m, the search is determined to be correct.

5. The shield posture measurement and guidance method without moving the station according to claim 1 is characterized in that: In the step (6), the angle .

6. The shield posture measurement and guidance method without moving the station according to claim 1 is characterized in that: In the step (7), the averaging calculation includes calculating the average of the two observed distance values and calculating the average of the two observed azimuth angles.

7. The shield posture measurement and guidance method without moving the station according to claim 1 is characterized in that: In step (8), if the shield machine turns and the total station and any prism are not transparent, or when the total station has a prism search error for more than three times in a row and it is confirmed that there is no obstruction between the total station and the prism, it is necessary to move the prisms forward according to the layout method of step (2).

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