Shield tunneling axis trajectory planning method and system based on deviation rectification capability constraint

Abstract

The invention belongs to the technical field of shield construction, and discloses a shield tunneling axis track planning method based on deviation rectification capability constraint, which comprises the following steps: substituting limit deviation rectification moment which can be provided by a thrust cylinder at present into a mechanical model in the tunneling process of a shield tunneling machine, and calculating the minimum deviation rectification radius under the constraint of a mechanical level. And the minimum deviation rectifying radius of the shield tunneling machine at the current position is obtained by combining the minimum deviation rectifying radius of the geometric layer and the minimum deviation rectifying radius of the mechanical layer. According to the method, trajectory planning is carried out based on the deviation rectification capability evaluation model, trajectory deviation rectification under various conditions can be adapted, the model considers constraints of a geometric level and a mechanical level on the minimum deviation rectification radius at the same time, the obtained minimum deviation rectification radius is high in accuracy, and reliable support is provided for subsequent trajectory planning. And meanwhile, a quintic polynomial curve is sampled for fitting, so that continuous and smooth track, continuous track curvature and continuous curvature change rate can be achieved, the motion characteristics of the shield tunneling machine are met, and the thrust oil cylinder is easy to control deviation rectifying torque following.

Description

Technical Field

[0001] The invention belongs to the technical field of shield construction, and in particular relates to a shield tunneling axis trajectory planning method and system based on deviation correction capability constraints. Background Art

[0002] Shield technology is a safe, efficient, environmentally friendly, highly applicable and high-quality tunneling method. With its many advantages, this technology has been widely used in tunnel projects such as subways, railways, highways, and hydropower. However, during the construction of shield tunnels, due to changes in geological conditions and the complexity of the construction environment, the shield tunneling trajectory is often difficult to keep consistent with the design axis, and trajectory deviations such as upward, knocking, serpentine and horizontal deviation often occur. This deviation phenomenon not only causes tunnel overrun accidents and significantly reduces construction efficiency, but also leads to difficulties in segment assembly, damage and failure of shield tail seals, and even leads to the abandonment of the formed tunnel, causing construction failure and huge economic losses.

[0003] In the existing shield deviation correction trajectory planning methods, some omit the trajectory planning part, and directly control the excavation parameters by analyzing the shield machine's posture deviation to return the shield machine to the correct position. CN202111203818.X proposes an intelligent decision-making method for shield excavation correction based on reinforcement learning. This method establishes a shield deviation correction decision-making model, conducts multiple rounds of training in a simulation environment, and optimizes the final model. However, the original training simulation environment is not suitable for all tunnel conditions. The geological conditions and other environmental factors of different tunnels are different. When the model is applied to the construction of a new tunnel, it is necessary to rebuild the simulation environment and retrain the model, which leads to the lack of versatility and interpretability of this method. In other trajectory planning methods, a comprehensive and accurate evaluation of the current deviation correction capability of the shield machine is required. However, existing methods only consider the constraints on the deviation correction capability at the geometric level (shield tail gap, thrust cylinder stroke difference, etc.), while ignoring the limitations on the deviation correction capability at the mechanical level (limit deviation correction torque). This will affect the accuracy of the current deviation correction capability evaluation and blur the constraints of subsequent deviation correction trajectory planning. At the same time, most of the deviation correction curves are selected from cubic polynomials or circular curve splicing combinations, which will lead to discontinuous curvature at the connection, which is not conducive to the shield machine controlling the cylinder advancement, and will also cause sudden changes in centrifugal force during excavation, affecting the quality of tunnel construction.

[0004] In view of the above problems, it is particularly important to invent a shield axis correction trajectory planning method that has strong versatility, smooth trajectory, and meets the motion characteristics of the shield machine.

[0005] Through the above analysis, the problems and defects of the prior art are as follows:

[0006] The universality of the model training method is low, and the model needs to be retrained in the new environment. The correction ability evaluation model of the correction curve method is not sound, the trajectory curvature is discontinuous, the smoothness is low, and it does not meet the motion characteristics of the shield machine. Summary of the invention

[0007] In view of the problems existing in the prior art, the present invention provides a shield tunneling axis trajectory planning method based on deviation correction capability constraints.

[0008] The present invention is implemented in this way: a shield tunneling axis trajectory planning method based on deviation correction capability constraint includes:

[0009] S1. Evaluate the shield machine's deviation correction capability with the minimum turning radius, obtain the shield machine's shield tail gap, thrust cylinder stroke difference, and articulated device related information, and calculate the minimum deviation correction radius under geometric constraints;

[0010] S2, by substituting the current limit deviation correction torque that the propulsion cylinder can provide into the mechanical model of the shield machine during excavation, the minimum deviation correction radius under the mechanical constraint is calculated;

[0011] S3. Combining the minimum correction radius at the geometric level and the mechanical level, the minimum correction radius of the shield machine at the current position is obtained, and it is used as the correction capacity constraint for trajectory planning;

[0012] S4, obtaining the posture information of the shield machine at the current position, obtaining the position information of the design axis DTA; establishing the Frenet coordinate system with the design axis DTA as the reference line;

[0013] S5. Perform trajectory planning in the Frenet coordinate system, take the current position of the shield machine as the starting point for deviation correction, take points with equal distances in a suitable interval along the DTA as the end point of the deviation correction trajectory, use a quintic polynomial curve to fit the start and end points, and obtain a deviation correction trajectory group; according to the minimum deviation correction radius constraint, find the deviation correction trajectory that first meets the constraint along the excavation direction, and take the interval between the end point of the trajectory and the adjacent end point of the trajectory on the left as the new planning interval, and continue to take points with equal distances in the new planning interval as the end point of the trajectory, repeat the above steps and keep subdividing the interval until the final point is found;

[0014] S6. Convert the deviation correction trajectory corresponding to the final point from the Frenet coordinate system to the rectangular coordinate system to obtain the deviation correction trajectory of the shield axis.

[0015] Furthermore, in step S1, the geometric constraints are divided into shield tail gap, thrust cylinder stroke difference, and shield articulation device; the minimum correction radius R under the shield tail gap constraint mj The calculation process is:

[0016]

[0017] Where R1 is the segment radius, δ is the shield tail gap, and l is the length of the shield tail part;

[0018] Minimum deviation correction radius R under the constraint of propulsion cylinder stroke difference mF The calculation process is:

[0019]

[0020] Where R F is the cylinder installation radius, δ F is the maximum stroke difference of the thrust cylinder, is the deflection angle of the cutter head centerline when the thrust cylinder is at the maximum stroke difference, l s The radius R of the shield machine mF The rotation angle is Distance traveled

[0021] Minimum deviation correction radius R under the constraint of the articulated device mc The calculation process is:

[0022]

[0023] Where D is the diameter of the shield machine, (x H ,y H ) is the coordinate of the shield tail point in the coordinate system established with the cutter head center as the origin;

[0024] Then the minimum correction radius under geometric constraints is obtained;

[0025] R jmin =max{R mj ,R mc ,R mF}.

[0026] Furthermore, in step S2, the mechanical constraint is the limit deviation correction torque that the propulsion cylinder can provide. The limit deviation correction torque is introduced into the mechanical model of the shield machine. In the mechanical model, the torque on the shield machine is the resistance torque M of the cutterhead excavation. D , the force and moment of the surrounding soil M RV , shield machine gravity moment M G , Propulsion cylinder correction torque T RV , the shield machine moves very slowly during the excavation process, and the moment of force on the shield machine can be considered balanced. According to the formula:

[0027] M G +M D +M RV +T RV =0

[0028] Thus, the minimum correction radius R under mechanical constraints is calculated. Lmin .

[0029] Furthermore, in step S3, the minimum deviation correction radius r of the current position of the shield machine is the minimum deviation correction radius R under the geometric level constraint. jmin and the minimum correction radius R under mechanical constraints Lmin The maximum value in, that is, r = max{R jmin ,R Lmin}, and use r as a constraint to carry out the next step of trajectory planning.

[0030] Further, in step S4, the position information of the current position of the shield machine specifically includes: the coordinates of the shield machine (x, y, z), the direction angle θ of the shield machine in the xoy plane, the direction angle θ of the shield machine in the xoz plane The current curvature κ of the shield machine's excavation axis; The location information of DTA is the point obtained by discretizing DTA according to a fixed mileage; The establishment of the Frenet coordinate system is to decouple the three-dimensional space into xoy and xoz planes, plan on the two planes, and establish the Frenet coordinate system with the projection of DTA on the two planes as the reference line.

[0031] Further, in step S5, trajectory planning is performed in the Frenet coordinate system, and the current posture of the shield machine is projected from the Cartesian coordinate system to the Frenet coordinate system. The projection process is: [x, y, θ, k]→[s0, l0, l′0, l″0], where s0 and l0 are coordinates in the Frenet coordinate system, and l0′, l0″, l0″′ are the first-order derivative, second-order derivative, and third-order derivative of l0 with respect to s0; a suitable interval is taken along the excavation direction on the DTA, and points are taken at equal distances in the interval as the end points of the deviation correction trajectory, and the current position of the shield machine [s0, l0, l′0, l″0] and the point [s1, l1, l1′, l1″] are connected with a quintic polynomial curve as the deviation correction trajectory;

[0032] l(s)=a5s 5 +a4s 4 +a3s 3 +a2s 2 +a1s+a0

[0033] According to the start and end point information:

[0034]

[0035] The coefficients of the quintic polynomial [a1, a2, a3, a4, a5] can be solved. Each point corresponds to a quintic polynomial curve, forming a correction trajectory group. According to the minimum correction radius constraint, find the correction trajectory that first meets the constraint along the excavation direction, and use the interval between the end point of the trajectory and the left adjacent trajectory end point as the new planning interval. Continue to take points with equal distances as the trajectory end points in the new planning interval and repeat the above steps to continuously subdivide the interval until the final point is found.

[0036] In step S6, the trajectory corresponding to the final point is converted from the Frenet coordinate system to the Cartesian coordinate system to obtain the shield axis correction trajectory; this trajectory is the trajectory with the minimum mileage projected on the DTA that meets the minimum correction radius constraint of the shield machine.

[0037] Another object of the present invention is to provide a shield tunneling axis trajectory planning system based on deviation correction capability constraint, comprising:

[0038] The calculation module is used to evaluate the shield machine's deviation correction capability based on the minimum turning radius, obtain information related to the shield tail gap, thrust cylinder stroke difference, and articulation device, and thus calculate the minimum deviation correction radius under geometric constraints;

[0039] A substitution module is used to substitute the limit deviation correction torque that the propulsion cylinder can currently provide into the mechanical model of the shield machine during excavation, thereby calculating the minimum deviation correction radius under the constraints of the mechanical level;

[0040] The trajectory planning module is used to combine the minimum correction radius at the geometric level and the mechanical level to obtain the minimum correction radius of the shield machine at the current position, and use it as the correction capacity constraint for trajectory planning;

[0041] The coordinate system establishment module is used to obtain the posture information of the shield machine at the current position and the position information of the design axis DTA; the Frenet coordinate system is established with the design axis DTA as the reference line;

[0042] The fitting module is used to plan the trajectory in the Frenet coordinate system. The current position of the shield machine is used as the starting point of the correction. Points with equal distances are taken along the DTA as the end points of the correction trajectory. The starting point and the end point are fitted with a quintic polynomial curve to obtain the correction trajectory group. According to the minimum correction radius constraint, the correction trajectory that first meets the constraint is found along the excavation direction. The interval between the end point of the trajectory and the adjacent end point on the left is used as the new planning interval. Points with equal distances are taken in the new planning interval as the end point of the trajectory. The above steps are repeated to continuously subdivide the interval until the final point is found.

[0043] The conversion module is used to convert the correction trajectory corresponding to the final point from the Frenet coordinate system to the rectangular coordinate system to obtain the shield axis correction trajectory.

[0044] Another object of the present invention is to provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the shield tunneling axis trajectory planning method based on the correction capability constraint.

[0045] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to execute the steps of the shield tunneling axis trajectory planning method based on correction capability constraints.

[0046] Another object of the present invention is to provide an information data processing terminal, which is used to implement the shield tunneling axis trajectory planning system based on the correction capability constraint.

[0047] In combination with the above technical solutions and the technical problems solved, the advantages and positive effects of the technical solutions to be protected by the present invention are as follows:

[0048] First, the shield machine correction capability evaluation model sampled by the present invention calculates the correction capability at the geometric and mechanical levels, which is more accurate than the previous method that only considers geometric constraints, making subsequent trajectory planning more realistic and preventing the shield machine from being unable to move forward along the planned trajectory.

[0049] 1. The present invention adopts a quintic polynomial curve for trajectory planning, which can adapt to trajectory correction in various situations.

[0050] 2. The present invention samples a quintic polynomial curve for trajectory planning, which can achieve continuous and smooth trajectory, continuous trajectory curvature, and continuous curvature change rate. It conforms to the motion characteristics of the shield machine and is easy to follow the correction torque of the propulsion cylinder control.

[0051] The present invention uses DTA as a reference line to establish a Frenet coordinate system, and can simply use longitudinal displacement and lateral displacement based on DTA to represent the current position, thereby reducing the complexity and difficulty of trajectory planning.

[0052] The optimal trajectory found by the present invention is the trajectory that meets the minimum curvature radius requirement and has the least mileage s of the point on the DTA. Unlike the previous evaluation criteria of arc length, the present invention uses the mileage of the point on the DTA as the evaluation criteria. The less mileage the deviation correction trajectory projects onto the DTA, the sooner the shield machine returns to the DTA, and the higher the quality of the target project.

[0053] Second, as auxiliary evidence of the inventiveness of the claims of the present invention, it is also reflected in the following important aspects:

[0054] (1) The expected benefits and commercial value of the technical solution of the present invention after transformation are as follows: During the tunneling process, the shield machine is affected by various sudden changes in environmental conditions, which inevitably causes the tunneling direction of the shield machine to deviate from the DTA. Manual operation is usually required for correction, and manual operation relies entirely on proficiency and experience, and mistakes are inevitable, resulting in serious consequences. This limitation seriously affects the efficiency and safety of construction. The shield tunneling axis trajectory planning method based on the correction capability constraint adopted by the present invention effectively overcomes this challenge, ensuring that when the shield machine deviates from the DTA, a correction trajectory that conforms to its motion characteristics can be planned in real time, guiding the shield machine back to the DTA, and realizing the posture correction of the shield machine without manual control. This innovation not only improves the construction efficiency, but also enhances the safety of operation, thus having significant economic value. According to the data of the Tunneling Machinery Branch of the China Construction Machinery Industry Association, the annual output of shield machines is about 700 units. The correction trajectory planning system designed by the present invention is expected to create an annual economic value of about RMB 35 million.

[0055] (2) Whether the technical solution of the present invention solves the technical problems that people have been eager to solve but have never succeeded in solving: The present invention solves the problems of unreasonable evaluation of shield machine correction ability and discontinuous curvature of correction trajectory in the existing shield machine correction trajectory planning technology. The current shield machine correction trajectory planning method only considers the constraints on geometric dimensions for the correction ability, and does not consider the constraints on the mechanical level of the shield machine. In addition, the correction curve linear shape used in the existing trajectory planning method adopts cubic polynomials, reverse double arcs, etc. These linear shapes will cause discontinuity of curvature at connection points such as the starting and ending points.

[0056] The present invention establishes a mechanical model of a shield machine, analyzes the constraints of the shield machine's deviation correction capability at the mechanical level, and accurately calculates the minimum turning radius of the shield machine under the mechanical constraints.

[0057] In addition, the present invention adopts a quintic polynomial curve as the deviation correction line shape, thereby ensuring that the curvature on the entire deviation correction track is continuous everywhere.

[0058] (3) Whether the technical solution of the present invention overcomes technical prejudice: BRIEF DESCRIPTION OF THE DRAWINGS

[0059] Figure 1 It is a flow chart of a shield tunneling axis trajectory planning method based on deviation correction capability constraints provided in an embodiment of the present invention.

[0060] Figure 2 It is a structural block diagram of a shield tunneling axis trajectory planning system based on deviation correction capability constraints provided in an embodiment of the present invention.

[0061] Figure 3It is a schematic diagram of the conversion from a rectangular coordinate system to a Frenet coordinate system provided by an embodiment of the present invention.

[0062] Figure 4 It is a schematic diagram of a correction trajectory group generated in the Frenet coordinate system provided in an embodiment of the present invention.

[0063] Figure 5 It is a schematic diagram of trajectory group screening and transition interval determination in the Frenet coordinate system provided by an embodiment of the present invention.

[0064] Figure 6 This is a schematic diagram of the optimal trajectory provided by an embodiment of the present invention.

[0065] Figure 7 Effect diagram of the embodiment of the present invention compared with manual correction. DETAILED DESCRIPTION

[0066] In order to make the purpose, technical solution and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0067] like Figure 1 As shown, a shield tunneling axis trajectory planning method based on deviation correction capability constraint provided by an embodiment of the present invention includes the following steps:

[0068] S1. Evaluate the shield machine's deviation correction capability with the minimum turning radius, obtain the shield machine's shield tail gap, thrust cylinder stroke difference, and articulated device related information, and calculate the minimum deviation correction radius under geometric constraints;

[0069] S2, by substituting the current limit deviation correction torque that the propulsion cylinder can provide into the mechanical model of the shield machine during excavation, the minimum deviation correction radius under the mechanical constraint is calculated;

[0070] S3. Combining the minimum correction radius at the geometric level and the mechanical level, the minimum correction radius of the shield machine at the current position is obtained, and it is used as the correction capacity constraint for trajectory planning;

[0071] S4, obtaining the posture information of the shield machine at the current position, obtaining the position information of the design axis DTA; establishing the Frenet coordinate system with the design axis DTA as the reference line;

[0072] S5. Perform trajectory planning in the Frenet coordinate system, take the current position of the shield machine as the starting point for deviation correction, take points with equal distances in a suitable interval along the DTA as the end point of the deviation correction trajectory, use a quintic polynomial curve to fit the start and end points, and obtain a deviation correction trajectory group; according to the minimum deviation correction radius constraint, find the deviation correction trajectory that first meets the constraint along the excavation direction, and take the interval between the end point of the trajectory and the adjacent end point of the trajectory on the left as the new planning interval, and continue to take points with equal distances in the new planning interval as the end point of the trajectory, repeat the above steps and keep subdividing the interval until the final point is found;

[0073] S6. Convert the deviation correction trajectory corresponding to the final point from the Frenet coordinate system to the rectangular coordinate system to obtain the deviation correction trajectory of the shield axis.

[0074] The shield machine's deviation correction capability is subject to geometric and mechanical constraints. At the geometric level, the minimum turning radius that the shield machine can achieve is determined by calculating the shield tail gap, the thrust cylinder stroke difference, and the relevant parameters of the articulated device. This minimum turning radius defines the minimum trajectory bending capability that the shield machine can achieve under geometric conditions. At the mechanical level, by establishing a mechanical model of the shield machine and substituting the limit deviation correction torque provided by the thrust cylinder, the minimum deviation correction radius that the shield machine can achieve during the excavation process is calculated. These two constraints jointly determine the minimum deviation correction radius of the shield machine's current excavation position, thereby defining the deviation correction capability of the shield machine.

[0075] Based on the minimum correction radius at the geometric and mechanical levels, combined with the current position of the shield machine and the position information of the design axis DTA, a Frenet coordinate system is established around the design axis DTA. Trajectory planning starts from the current position of the shield machine (the starting point of the correction), takes equally spaced points along the DTA direction as the end points of the correction trajectory, and uses a quintic polynomial curve to fit the path between the starting point and the end point to generate a set of candidate trajectory paths. In the generated correction trajectory, check one by one whether the trajectory meets the current minimum correction radius constraint, and select the trajectory that first meets the constraint.

[0076] For the trajectory group that meets the correction radius constraint, select the trajectory endpoint that meets the constraint and form an interval between it and the adjacent trajectory endpoint on the left. Further subdivide the interval to take points at equal intervals, recalculate the new correction trajectory, and use the same screening method to find a more accurate trajectory endpoint. By gradually narrowing the planning interval and subdividing the trajectory endpoint, the final correction trajectory is iteratively calculated to ensure that the trajectory meets the correction radius constraint and achieves the minimum trajectory deviation.

[0077] The final selected deviation correction trajectory is expressed in the Frenet coordinate system to facilitate optimization relative to the design axis. However, in order to achieve actual tunneling control, the final trajectory needs to be converted from the Frenet coordinate system to the rectangular coordinate system. The shield axis deviation correction trajectory obtained after the conversion can be directly used to guide the tunneling operation of the shield machine, ensuring that the shield machine corrects along the optimized trajectory, improving tunneling accuracy and reducing construction risks.

[0078] In step S1 provided in the embodiment of the present invention, the geometric constraints are divided into the shield tail gap, the thrust cylinder stroke difference, and the shield articulation device; the minimum deviation correction radius R under the shield tail gap constraint mj The calculation process is:

[0079]

[0080] Where R1 is the segment radius, δ is the shield tail gap, and l is the length of the shield tail part;

[0081] Minimum deviation correction radius R under the constraint of propulsion cylinder stroke difference mF The calculation process is:

[0082]

[0083] Where R F is the cylinder installation radius, δ F is the maximum stroke difference of the thrust cylinder, is the deflection angle of the cutter head centerline when the thrust cylinder is at the maximum stroke difference, l s The radius R of the shield machine mF The rotation angle is Distance traveled

[0084] Minimum deviation correction radius R under the constraint of the articulated device mc The calculation process is:

[0085]

[0086] Where D is the diameter of the shield machine, (x H ,y H ) is the coordinate of the shield tail point in the coordinate system established with the cutter head center as the origin;

[0087] Then the minimum correction radius under geometric constraints is obtained;

[0088] R jmin =max{R mj ,R mc ,R mF}.

[0089] In step S2 provided in the embodiment of the present invention, the constraint at the mechanical level is the limit deviation correction torque that the propulsion cylinder can provide. The limit deviation correction torque is introduced into the mechanical model of the shield machine. In the mechanical model, the torque on the shield machine is the resistance torque M on the cutterhead excavation. D , the force and moment of the surrounding soil M RV , shield machine gravity moment M G , Propulsion cylinder correction torque T RV , the shield machine moves very slowly during the excavation process, and the moment of force on the shield machine can be considered balanced. According to the formula:

[0090] M G +M D +M RV +T RV =0

[0091] Thus, the minimum correction radius R under mechanical constraints is calculated. Lmin .

[0092] In step S3 provided in the embodiment of the present invention, the minimum deviation correction radius r of the current position of the shield machine is the minimum deviation correction radius R under the geometric level constraint. jmin and the minimum correction radius R under mechanical constraints Lmin The maximum value in, that is, r = max{R jmin ,R Lmin}, and use r as a constraint to carry out the next step of trajectory planning.

[0093] In step S4 provided in the embodiment of the present invention, the position information of the current position of the shield machine specifically includes: the coordinates of the shield machine (x, y, z), the direction angle θ of the shield machine in the xoy plane, the direction angle θ of the shield machine in the xoz plane The current curvature κ of the shield machine's excavation axis; The location information of DTA is the point obtained by discretizing DTA according to a fixed mileage; The establishment of the Frenet coordinate system is to decouple the three-dimensional space into xoy and xoz planes, plan on the two planes, and establish the Frenet coordinate system with the projection of DTA on the two planes as the reference line.

[0094] In step S5 provided by the embodiment of the present invention, trajectory planning is performed in the Frenet coordinate system, and the current posture of the shield machine is projected from the Cartesian coordinate system to the Frenet coordinate system. The projection process is: [x, y, θ, k]→[s0, l0, l′0, l″0], wherein s0 and l0 are coordinates in the Frenet coordinate system, and l0′, l0″, l0″′ are the first-order derivative, second-order derivative, and third-order derivative of l0 with respect to s0; a suitable interval is taken along the excavation direction on the DTA, and points are taken at equal distances in the interval as the end points of the deviation correction trajectory, and the current position of the shield machine [s0, l0, l′0, l″0] and the taken point [s1, l1, l1′, l1″] are connected with a quintic polynomial curve as the deviation correction trajectory;

[0095] l(s)=a5s 5 +a4s 4 +a3s 3 +a2s 2 +a1s+a0

[0096] According to the start and end point information:

[0097]

[0098] The coefficients of the quintic polynomial [a1, a2, a3, a4, a5] can be solved. Each point corresponds to a quintic polynomial curve, forming a correction trajectory group. According to the minimum correction radius constraint, find the correction trajectory that first meets the constraint along the excavation direction, and use the interval between the end point of the trajectory and the left adjacent trajectory end point as the new planning interval. Continue to take points with equal distances as the trajectory end points in the new planning interval and repeat the above steps to continuously subdivide the interval until the final point is found.

[0099] In step S6, the trajectory corresponding to the final point is converted from the Frenet coordinate system to the Cartesian coordinate system to obtain the shield axis correction trajectory; this trajectory is the trajectory with the minimum mileage projected on the DTA that meets the minimum correction radius constraint of the shield machine.

[0100] like Figure 2 As shown, a shield tunneling axis trajectory planning system based on deviation correction capability constraint provided by an embodiment of the present invention includes:

[0101] The calculation module is used to evaluate the shield machine's deviation correction capability based on the minimum turning radius, obtain information related to the shield tail gap, thrust cylinder stroke difference, and articulation device, and thus calculate the minimum deviation correction radius under geometric constraints;

[0102] A substitution module is used to substitute the limit deviation correction torque that the propulsion cylinder can currently provide into the mechanical model of the shield machine during excavation, thereby calculating the minimum deviation correction radius under the constraints of the mechanical level;

[0103] The trajectory planning module is used to combine the minimum correction radius at the geometric level and the mechanical level to obtain the minimum correction radius of the shield machine at the current position, and use it as the correction capacity constraint for trajectory planning;

[0104] The coordinate system establishment module is used to obtain the posture information of the shield machine at the current position and the position information of the design axis DTA; the Frenet coordinate system is established with the design axis DTA as the reference line;

[0105] The fitting module is used to plan the trajectory in the Frenet coordinate system. The current position of the shield machine is used as the starting point of the correction. Points with equal distances are taken along the DTA as the end points of the correction trajectory. The starting point and the end point are fitted with a quintic polynomial curve to obtain the correction trajectory group. According to the minimum correction radius constraint, the correction trajectory that first meets the constraint is found along the excavation direction. The interval between the end point of the trajectory and the adjacent end point on the left is used as the new planning interval. Points with equal distances are taken in the new planning interval as the end point of the trajectory. The above steps are repeated to continuously subdivide the interval until the final point is found.

[0106] The conversion module is used to convert the correction trajectory corresponding to the final point from the Frenet coordinate system to the rectangular coordinate system to obtain the shield axis correction trajectory.

[0107] Another object of the present invention is to provide a computer device, which includes a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the shield tunneling axis trajectory planning method based on the correction capability constraint.

[0108] Another object of the present invention is to provide a computer-readable storage medium storing a computer program, which, when executed by a processor, enables the processor to execute the steps of the shield tunneling axis trajectory planning method based on correction capability constraints.

[0109] Another object of the present invention is to provide an information data processing terminal, which is used to implement the shield tunneling axis trajectory planning system based on the correction capability constraint.

[0110] The present invention is specifically implemented:

[0111] Example 1: In a tunnel excavation project, the shield machine deviates from the DTA and the shield axis needs to be corrected.

[0112] According to the method flow chart, the specific steps are as follows:

[0113] S1. Use the minimum turning radius to evaluate the shield machine's ability to correct deviations, obtain information about the shield machine's tail clearance, thrust cylinder stroke difference, and articulated device, and thereby calculate the minimum correction radius under geometric constraints.

[0114] S2. Substitute the ultimate deviation correction torque that the thrust cylinder can currently provide into the mechanical model of the shield machine during excavation, thereby calculating the minimum deviation correction radius under mechanical constraints.

[0115] S3. Combining the minimum correction radius at the geometric level and the mechanical level, the minimum correction radius of the shield machine at the current position is obtained, and it is used as the correction capacity constraint for trajectory planning.

[0116] S4. Obtain the posture information of the shield machine at the current position, obtain the position information of the design axis DTA, and establish the Frenet coordinate system with the design axis DTA as the reference line.

[0117] like Figure 4 As shown, S5, trajectory planning is performed in the Frenet coordinate system, the current position of the shield machine is used as the correction starting point, and points are taken at equal distances in a suitable interval along the DTA as the correction trajectory end point, and the starting point and end point are fitted using a quintic polynomial curve to obtain a correction trajectory group. According to the minimum correction radius constraint, the correction trajectory that first meets the constraint is found along the excavation direction, and the interval between the end point of the trajectory and the adjacent trajectory end point on the left is used as the new planning interval. In the new planning interval, points are taken at equal distances as the trajectory end point. Repeat the above steps and keep subdividing the interval until the final point is found.

[0118] like Figure 3 As shown, S6, the deviation correction trajectory corresponding to the final point is converted from the Frenet coordinate system to the rectangular coordinate system to obtain the deviation correction trajectory of the shield axis.

[0119] Among them, in step S1, the minimum shield tail gap δ is 20 cm, the segment width B is 2 meters, the shield tail length l is 3 meters, and the segment radius R1 is 14.8 meters. According to the formula:

[0120]

[0121] Calculate the minimum correction radius R under the shield tail gap constraint mj It is 239 meters.

[0122] Maximum cylinder stroke difference δ F 0.1m, the shield machine rotation angle The length of the arc l s The cylinder installation radius R is 1 meter. F is 14.6 meters, according to the formula:

[0123]

[0124] Calculate the minimum correction radius R under the constraint of cylinder stroke difference mF It is 292 meters.

[0125] The shield machine has no articulated device, the length of the shield machine L0 is 80 meters, the single forward excavation stroke S of the shield machine is 2 meters, and the maximum lateral displacement δ of a excavation stroke is 10 meters. According to the formula:

[0126]

[0127] Calculate the minimum correction radius R without articulated constraints mc The minimum correction radius R at the geometric level can be obtained. jmin =max{R mj ,R mF ,R mc}=355 meters.

[0128] Among them, in step S2, according to the mechanical model of the shield machine, the resistance torque M of the cutterhead excavation is D , the force and moment of the surrounding soil M RV , shield machine gravity moment M G , Propulsion cylinder correction torque T RV , according to the formula:

[0129] M D +M RV +M G +T RV =0

[0130] Thus, the minimum correction radius R under mechanical constraints is calculated. Lmin It is 245 meters.

[0131] Among them, in step S3, the minimum correction radius under the constraints of the comprehensive mechanical level and geometric level can be obtained as 355 meters for the shield machine, which provides constraints for the subsequent trajectory planning.

[0132] Among them, the posture information of the current position of the shield machine in step S4 specifically includes: the shield machine coordinates (0, 0.05, 0.05) in m, the direction angle θ of the shield machine in the xoy plane = 1.5°, the direction angle in the xoz plane The current curvature of the tunneling axis of the shield machine is κ = 1 / 500m. DTA is a straight line segment, and its direction is along the x-axis. Decouple the three-dimensional space into xoy and xoz planes, and plan on the xoy plane first. The Frenet coordinate system uses DTA as a reference line to transform the shield machine posture information from the Cartesian coordinate system to the Frenet coordinate system. The conversion process is:

[0133] [x,y,θ,k]→[s0,l0,l′0,l″0]

[0134] [s0,l0,l′0,l′0]=[0,0.05,0,0]

[0135] Where x, y are the coordinates of the shield machine in the xoy plane, θ is the direction angle of the shield machine in the xoy plane, κ is the current curvature of the actual excavation axis of the shield machine, s0 is the horizontal coordinate of the shield machine in the Frenet coordinate system, also known as the mileage coordinate, l0 is the vertical coordinate in the Frenet coordinate system, that is, the distance from the point to the DTA, l′0 is the derivative of l0 with respect to s0, and l″0 is the second-order derivative of l0 with respect to s0.

[0136] Similarly, plan on the xoz plane and establish the Frenet coordinate system. The position information of the shield machine in the Frenet coordinate system:

[0137] [x,z,θ,k]→[s0,l0,l′0,l″0]

[0138] [s0,l0,l′0,l″0]=[0,0.05,0,0]

[0139] like Figure 5 As shown, in step S5, in the Frenet coordinate system, an interval of 6m to 26m is taken along the S axis in the DTA excavation direction, ten points are taken at equal distances in the interval, and the current position of the shield machine [s0, l0, l0′, l0″] and the taken point [s1, l1, l1′, l1″] are connected by a quintic polynomial curve as the deviation correction trajectory. Suppose the expression of the quintic polynomial curve is:

[0140] l(s)=a5s 5 +a4s 4 +a3s 3 +a2s 2 +a1s+a0

[0141] According to the start and end point information:

[0142]

[0143] The coefficients of the quintic polynomial [a1, a2, a3, a4, a5] can be solved, and each point corresponds to a quintic polynomial curve, forming a correction trajectory group. It is known that the minimum correction radius of the shield machine is 355m. In the correction trajectory group, according to the minimum correction radius constraint, find the correction trajectory that first meets the constraint along the excavation direction, and use the interval between the end point of the trajectory and the left adjacent trajectory end point as the new planning interval. Continue to take points at equal distances in the new planning interval as the trajectory end point and repeat the above steps to continuously subdivide the interval until the final point is found.

[0144] According to the above scheme, in step S6, the deviation correction trajectory corresponding to the final point is converted from the Frenet coordinate system to the rectangular coordinate system to obtain the shield axis deviation correction trajectory as follows: Figure 6 shown.

[0145] 1. Specific application fields or related products of the present invention.

[0146] The present invention is applied to the construction sites of Chongtai Tunnel, Jinwei Tunnel and Tongsu Jiayong Tunnel. The trajectory correction software is integrated on the Jetson Nano AI embedded development board. The development board reads the shield machine posture and DTA and other related information, calculates the optimal correction trajectory, and transmits the trajectory information to the shield machine propulsion system to guide the shield machine back to the DTA. No manual assistance is required throughout the process, and the automatic driving of the shield machine is realized, which greatly improves the construction safety and work efficiency, and saves about 10% of the operating cost.

[0147] 2. Relevant evidence of the technical effects obtained by the embodiments of the present invention.

[0148] At the construction site, the algorithm of the present invention is used to correct the deviation according to different deviation conditions, and the obtained correction information table and correction trajectory diagram are shown as follows:

[0149]

[0150] Figure 7 As shown, compared with manual deviation correction, the length of the deviation correction track planned by the present invention is reduced by about one tenth.

[0151] It should be noted that the embodiments of the present invention can be implemented by hardware, software, or a combination of software and hardware. The hardware part can be implemented using dedicated logic; the software part can be stored in a memory and executed by an appropriate instruction execution system, such as a microprocessor or dedicated design hardware. It can be understood by a person of ordinary skill in the art that the above-mentioned devices and methods can be implemented using computer executable instructions and / or contained in a processor control code, such as a carrier medium such as a disk, CD or DVD-ROM, a programmable memory such as a read-only memory (firmware), or a data carrier such as an optical or electronic signal carrier. Such code is provided on the carrier medium. The device and its modules of the present invention can be implemented by hardware circuits such as very large-scale integrated circuits or gate arrays, semiconductors such as logic chips, transistors, etc., or programmable hardware devices such as field programmable gate arrays, programmable logic devices, etc., can also be implemented by software executed by various types of processors, and can also be implemented by a combination of the above-mentioned hardware circuits and software, such as firmware.

[0152] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any modifications, equivalent substitutions and improvements made by any technician familiar with the technical field within the technical scope disclosed by the present invention and within the spirit and principle of the present invention should be covered by the protection scope of the present invention.

Claims

1. A shield tunneling axis trajectory planning method based on deviation correction capability constraint, characterized in that: The following steps are involved: S1. Evaluate the shield machine's deviation correction capability with the minimum turning radius, obtain the shield machine's shield tail gap, thrust cylinder stroke difference, and articulated device related information, and calculate the minimum deviation correction radius under geometric constraints; S2, by substituting the current limit deviation correction torque that the propulsion cylinder can provide into the mechanical model of the shield machine during excavation, the minimum deviation correction radius under the mechanical constraint is calculated; S3. Combining the minimum correction radius at the geometric level and the mechanical level, the minimum correction radius of the shield machine at the current position is obtained, and it is used as the correction capacity constraint for trajectory planning; S4, obtaining the posture information of the shield machine at the current position, and obtaining the position information of the design axis DTA; Establish the Frenet coordinate system with the design axis DTA as the reference line; S5. Perform trajectory planning in the Frenet coordinate system, take the current position of the shield machine as the starting point for deviation correction, take points with equal distances in a suitable interval along the DTA as the end point of the deviation correction trajectory, use a quintic polynomial curve to fit the start and end points, and obtain a deviation correction trajectory group; according to the minimum deviation correction radius constraint, find the deviation correction trajectory that first meets the constraint along the excavation direction, and take the interval between the end point of the trajectory and the adjacent end point of the trajectory on the left as the new planning interval, and continue to take points with equal distances in the new planning interval as the end point of the trajectory, repeat the above steps and keep subdividing the interval until the final point is found; S6. Convert the deviation correction trajectory corresponding to the final point from the Frenet coordinate system to the rectangular coordinate system to obtain the deviation correction trajectory of the shield axis.

2. The shield tunneling axis trajectory planning method based on deviation correction capability constraint as claimed in claim 1 is characterized in that: In step S1, the geometric constraints are divided into shield tail gap, thrust cylinder stroke difference, and shield articulation device; the minimum correction radius R under the shield tail gap constraint mj The calculation process is: Where R1 is the segment radius, δ is the shield tail gap, and l is the length of the shield tail part; Minimum deviation correction radius R under the constraint of propulsion cylinder stroke difference mF The calculation process is: Where R F is the cylinder installation radius, δ F is the maximum stroke difference of the thrust cylinder, is the deflection angle of the cutter head centerline when the thrust cylinder is at the maximum stroke difference, l s The radius R of the shield machine mF The rotation angle is Distance traveled Minimum deviation correction radius R under the constraint of the articulated device mc The calculation process is: Where D is the diameter of the shield machine, (x H ,y H ) is the coordinate of the shield tail point in the coordinate system established with the cutter head center as the origin; Then the minimum correction radius under geometric constraints is obtained; R jmin =max{R mj ,R mc ,R mF }。 3. The shield tunneling axis trajectory planning method based on deviation correction capability constraint as claimed in claim 1 is characterized in that: In step S2, the mechanical constraint is the limit deviation correction torque that the propulsion cylinder can provide. The limit deviation correction torque is introduced into the mechanical model of the shield machine. In the mechanical model, the torque on the shield machine is the resistance torque M of the cutterhead excavation. D , the force and moment of the surrounding soil M RV , shield machine gravity moment M G , Propulsion cylinder correction torque T RV , the shield machine moves very slowly during the excavation process, and the moment of force on the shield machine can be considered balanced. According to the formula: M G +M D +M RV +T RV =0 Thus, the minimum correction radius R under mechanical constraints is calculated. Lmin .

4. The shield tunneling axis trajectory planning method based on deviation correction capability constraint as claimed in claim 1 is characterized in that: In step S3, the minimum deviation correction radius r of the current position of the shield machine is the minimum deviation correction radius R under the geometric level constraint. jmin and the minimum correction radius R under mechanical constraints Lmin The maximum value in, that is, r = max{R jmin ,R Lmin }, and use r as a constraint to carry out the next step of trajectory planning.

5. The shield tunneling axis trajectory planning method based on deviation correction capability constraint as claimed in claim 1, characterized in that: In step S4, the position information of the current position of the shield machine specifically includes: the coordinates of the shield machine (x, y, z), the direction angle θ of the shield machine in the xoy plane, the direction angle θ of the shield machine in the xoz plane The current curvature κ of the shield machine's excavation axis; The location information of DTA is the point obtained by discretizing DTA according to a fixed mileage; The establishment of the Frenet coordinate system is to decouple the three-dimensional space into xoy and xoz planes, plan on the two planes, and establish the Frenet coordinate system with the projection of DTA on the two planes as the reference line.

6. The shield tunneling axis trajectory planning method based on deviation correction capability constraint as claimed in claim 1, characterized in that: In the step S5, trajectory planning is performed in the Frenet coordinate system, and the current posture of the shield machine is projected from the Cartesian coordinate system to the Frenet coordinate system. The projection process is: [x, y, θ, k]→[s0, l0, l0′, l0″]; a suitable interval is taken along the excavation direction on the DTA, and points are taken at equal distances in the interval as the end points of the deviation correction trajectory, and the current position of the shield machine [s0, l0, l0′, l0″] and the point [s1, l1, l1′, l1″] are connected with a quintic polynomial curve as the deviation correction trajectory; l(s)=a5s 5 +a4s 4 +a3s 3 +a2s 2 +a1s+a0 According to the start and end point information: The coefficients of the quintic polynomial [a1, a2, a3, a4, a5] can be solved. Each point corresponds to a quintic polynomial curve, forming a correction trajectory group. According to the minimum correction radius constraint, find the correction trajectory that first meets the constraint along the excavation direction, and use the interval between the end point of the trajectory and the left adjacent trajectory end point as the new planning interval. Continue to take points with equal distances as the trajectory end points in the new planning interval and repeat the above steps to continuously subdivide the interval until the final point is found. In step S6, the trajectory corresponding to the final point is converted from the Frenet coordinate system to the Cartesian coordinate system to obtain the shield axis correction trajectory; this trajectory is the trajectory with the minimum mileage projected on the DTA that meets the minimum correction radius constraint of the shield machine.

7. A shield tunneling axis trajectory planning system based on deviation correction capability constraint that implements the shield tunneling axis trajectory planning method based on deviation correction capability constraint as described in any one of claims 1 to 6, characterized in that: The shield tunneling axis trajectory planning system based on deviation correction capability constraint includes: The calculation module is used to evaluate the shield machine's deviation correction capability based on the minimum turning radius, obtain information related to the shield tail gap, thrust cylinder stroke difference, and articulation device, and thus calculate the minimum deviation correction radius under geometric constraints; A substitution module is used to substitute the limit deviation correction torque that the propulsion cylinder can currently provide into the mechanical model of the shield machine during excavation, thereby calculating the minimum deviation correction radius under the constraints of the mechanical level; The trajectory planning module is used to combine the minimum correction radius at the geometric level and the mechanical level to obtain the minimum correction radius of the shield machine at the current position, and use it as the correction capacity constraint for trajectory planning; The coordinate system establishment module is used to obtain the posture information of the shield machine at the current position and the position information of the design axis DTA; the Frenet coordinate system is established with the design axis DTA as the reference line; The fitting module is used to plan the trajectory in the Frenet coordinate system. The current position of the shield machine is used as the starting point of the correction. Points with equal distances are taken along the DTA as the end points of the correction trajectory. The starting point and the end point are fitted with a quintic polynomial curve to obtain the correction trajectory group. According to the minimum correction radius constraint, the correction trajectory that first meets the constraint is found along the excavation direction. The interval between the end point of the trajectory and the adjacent end point on the left is used as the new planning interval. Points with equal distances are taken in the new planning interval as the end point of the trajectory. The above steps are repeated to continuously subdivide the interval until the final point is found. The conversion module is used to convert the correction trajectory corresponding to the final point from the Frenet coordinate system to the rectangular coordinate system to obtain the shield axis correction trajectory.

8. A computer device, characterized in that: The computer device includes a memory and a processor, the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the shield tunneling axis trajectory planning method based on correction capability constraints as described in any one of claims 1-6.

9. A computer-readable storage medium storing a computer program, wherein when the computer program is executed by a processor, the processor executes the steps of the shield tunneling axis trajectory planning method based on correction capability constraint as described in any one of claims 1 to 6.

10. An information data processing terminal, characterized in that: The information data processing terminal is used to implement the shield tunneling axis trajectory planning system based on correction capability constraints as described in claim 7.

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