A method for calculating the thrust force redistribution of a shield propulsion system in a push-assemble synchronization mode

Abstract

The application provides a kind of push-pull synchronization mode under the shield propulsion system propulsion force redistribution calculation method, comprising the following steps: S1: according to the shield guidance system obtains historical shield pose information;S2: determine the shield pose change matrix;S3: determine the shield propulsion system structure parameters and segment structure parameters;S4: obtain all the cylinder thrust under push-pull alternation mode;S5: establish the force transmission equation of shield propulsion system;S6: establish the partition thrust redistribution equation under push-pull synchronization mode;S7: according to the thrust redistribution optimization principle, the partition thrust is optimized and solved, so as to obtain the redistribution thrust of the remaining cylinder when some cylinder group is missing. Realize the shield push-pull synchronization mode under the shield propulsion force redistribution, which can consider the shield tunneling pose, the shield propulsion system different partition mode and different missing cylinder group, ensure the equivalent driving force unchanged before and after thrust redistribution, and ensure that the shield machine can continue to advance along the established trajectory under push-pull synchronization mode.

Description

Technical Field

[0001] The present invention belongs to the field of shield construction, and in particular relates to a method for calculating propulsion force redistribution of a shield propulsion system in a push-and-splice synchronous mode. Background Art

[0002] Under normal circumstances, after a shield machine excavates one ring, it needs to stop for segment assembly. The specific assembly process is as follows: when assembling a certain segment in the shield tail, the propulsion system needs to withdraw the cylinder in the corresponding assembly area to leave working space for the segment assembly. After the segment is assembled, the retracted propulsion cylinder in the area is re-extended to press against the assembled segment. Then, the "withdraw-assemble-extend" cycle is carried out in the assembly order until all the segments of the ring are assembled into a ring, and then the next ring excavation operation is carried out. This propulsion method is also called "push-and-assemble alternately" or "propulsion-stop-assembly" operation method. Since the shield machine needs to stop frequently during the excavation process, it seriously restricts construction efficiency.

[0003] For this purpose, the shield's "push-and-splice synchronization" mode came into being. This mode means that during the assembly of a certain segment, the propulsion system withdraws the cylinder corresponding to the segment assembly area and leaves at least a ring of segment width space in which the segments are assembled. At the same time, the shield machine does not stop, and the propulsion system continues to rely on other hydraulic cylinders that have not been withdrawn to provide driving force, using their remaining stroke to advance forward, thereby achieving synchronous segment assembly during shield excavation, essentially improving construction efficiency. However, since the cylinder group corresponding to the segment assembly area has been withdrawn, resulting in the absence of the cylinder group in this area, how to ensure that the equivalent driving force of the remaining cylinder propulsion force is consistent with the equivalent driving force of all the original cylinder propulsion forces is the key significance of the shield thrust redistribution in the push-and-splice synchronization mode.

[0004] Most existing shield thrust distribution methods in the synchronous push-and-spin mode directly distribute the thrust of the missing cylinder group to the remaining cylinders through incremental or gradient distribution, ensuring only that the magnitude and point of application of the total thrust remain unchanged. This approach is feasible under the assumption that the shield propulsion cylinders are parallel to the shield axis. However, due to posture adjustments during shield tunneling, the shield propulsion cylinders are not completely parallel to the shield axis. In other words, the force system formed by the thrust of the shield hydraulic cylinders is not a spatially parallel force system. Therefore, it is unreasonable to simplify the thrust distribution directly to the center of the propulsion cylinders without considering their direction. Furthermore, as a redundant drive system, the shield propulsion system only ensures that the magnitude and point of application of the total thrust of the propulsion system remain unchanged, resulting in non-unique thrust distribution results. Improper thrust distribution settings can cause the shield propulsion mechanism to bear large internal forces, resulting in not only wasted hydraulic cylinder thrust but also potential damage to the shield propulsion mechanism. Therefore, while ensuring that the redistributed thrust of the shield propulsion system can balance the shield load, it is necessary to optimize the shield propulsion system's thrust redistribution.

[0005] Therefore, the prior art has the following problems:

[0006] (1) The existing thrust distribution method of the shield propulsion system in the push-and-spin synchronization mode cannot take into account the impact of the shield posture adjustment on the thrust direction of the cylinder, resulting in inaccurate thrust distribution.

[0007] (2) The existing thrust distribution method of the shield propulsion system in the push-and-spin synchronization mode does not optimize the distributed thrust, which may cause the shield propulsion mechanism to bear a large internal force, which not only wastes the thrust of the hydraulic cylinder, but also may damage the shield propulsion mechanism. Summary of the Invention

[0008] The present invention aims to provide a method for calculating the propulsion force redistribution of a shield propulsion system in a push-and-splice synchronous mode, so as to solve the above problems.

[0009] The technical solution of the present invention is:

[0010] A method for calculating propulsion force redistribution of a shield propulsion system in a push-and-spin synchronous mode comprises the following steps:

[0011] S1: Obtain historical shield posture information based on the shield guidance system;

[0012] S2: Determine the shield posture change matrix;

[0013] S3: Determine the structural parameters of the shield propulsion system and the segment structure parameters;

[0014] S4: Obtain the thrust of all cylinders in the push-and-spin alternating mode;

[0015] S5: Establish the force transfer equation of shield propulsion system;

[0016] S6: Establishing the partition thrust redistribution equation in the push-and-spin synchronization mode;

[0017] S7: Optimize and solve the partitioned thrust according to the thrust redistribution optimization principle to obtain the redistributed thrust of the remaining cylinders when some cylinder groups are missing.

[0018] Preferably, the historical shield posture information in S1 specifically includes: shield posture vector q = [xyz ψ θ φ] T ;

[0019] Among them, (x, y, z) represents the position coordinates of the center of the spherical joint distribution circle in front of the shield machine's propulsion cylinder; (ψ, θ, φ) represents the three attitude angles of the shield machine: roll angle, pitch angle and yaw angle.

[0020] Preferably, the shield posture change matrix calculation formula in S2 is:

[0021]

[0022] wherein, and respectively represent the posture matrix and position vector of the shield, and the calculation formulae are

[0023]

[0024] wherein, c represents the cosine function cos; s represents the sine function sin.

[0025] Preferably, the structure parameters of the shield propulsion system and the segment structure parameters in S3 specifically include: determining the shield propulsion system parameters according to the engineering data: the rear spherical hinge B of the propulsion oil cylinder i coordinate, i = 1, 2, 3, … n; n is the total number of the propulsion oil cylinder; and the segment is divided into blocks.

[0026] Preferably, the propulsion force vector composed of all the propulsion forces of the oil cylinders of the shield propulsion system in S4 is F d = [F1 F2…F n ] T .

[0027] Preferably, the force transmission equation of the shield propulsion system in S5 is obtained according to the static balance characteristics of the shield machine by using the virtual work principle; and the force transmission equation of the shield propulsion system is:

[0028] J T F d +F e = 0 (4)

[0029] wherein, F e is the equivalent load received in the shield tunneling process; J is the velocity Jacobian matrix of the shield propulsion mechanism, and the calculation formula is as follows:

[0030]

[0031] wherein, A u i is the unit direction vector of the i-th propulsion oil cylinder, and the calculation formula is:

[0032]

[0033] J T F d is the target equivalent driving force of the propulsion force of the shield propulsion system that is,

[0034]

[0035] wherein, G = J T represents the force Jacobian matrix of the shield propulsion mechanism, and is represented as

[0036] G=[G1 G2 … G n ] (8)

[0037] Preferably, S6 establishes a partition thrust redistribution equation in the push-and-spin synchronization mode, which is expressed as follows:

[0038]

[0039] in, It is defined as the reconstructed force Jacobian matrix of the shield propulsion mechanism, indicating that there is a missing cylinder group G in the shield propulsion system. j The force Jacobian matrix when , is the thrust vector of the redistributed cylinder that needs to be solved; The specific form is

[0040]

[0041] j is the missing cylinder group G j The corresponding segment model to be assembled is

[0042] j={F,L1,L2,B1,B2,…,BN r -3}

[0043] Among them, N r is the total number of segments in a ring;

[0044] Assume that cylinder group G is missing j The set of propulsion cylinder numbers in

[0045] G j ={j1,j2,…,j m} (11)

[0046] Where m is the missing cylinder group G j The number of oil cylinders included;

[0047] Due to the absence of cylinder group G j The thrust of the cylinder in the reconstructed force Jacobian matrix is ​​0, so the columns corresponding to the multiplication of the thrust of the missing cylinder group should be 6-dimensional 0 vectors, that is,

[0048]

[0049] Assume that the number of shield propulsion system partitions is N (3≤N≤n), and name the different partitions P1, P2, ..., PN in sequence. Assume that there are n partitions in the kth partition, that is, partition Pk. k propulsion cylinders, and the cylinder numbers are n in this partition k The thrust of the propulsion cylinders is the same, so there is

[0050]

[0051] wherein,

[0052]

[0053] The partitioned thrust redistribution equation of the shield propulsion system in the thrust-pushing synchronization mode is represented as

[0054]

[0055] wherein, H Gj is the reconstruction force Jacobian matrix of the shield propulsion mechanism partition, H Gj = [H P1 H P2 …H PN ], is the partitioned thrust formed by the redistribution of the thrust of all partitioned propulsion oil cylinders,

[0056] Preferably, S7 specifically comprises:

[0057] According to the number N of different partitions of the propulsion system, the shield redistribution of the partitioned thrust is discussed in different cases:

[0058] (1) When 3≤N<6

[0059] At this time, formula (16) is an over-determined equation, and the approximate solution is obtained by using the least square method. The optimization problem is described as:

[0060]

[0061] wherein, F max is the hydraulic oil cylinder thrust threshold;

[0062] (2) When N=6

[0063] At this time, formula (16) is a well-posed equation, and the optimization problem is described as:

[0064]

[0065] (3) When 6<N≤n

[0066] At this time, formula (16) is an under-determined equation, so that there are infinite solutions for the redistribution of the partitioned thrust. In order to avoid the waste or even damage of the shield propulsion mechanism caused by the excessive thrust, the force optimization is performed on the propulsion synchronization redistribution of the partitioned thrust by using the minimum force two-norm method, and the optimization problem is described as:

[0067]

[0068] In the formula, W is an N-order unit matrix;

[0069] According to the shield propulsion mechanism partition situation, the formula (17), (18) or (19) is optimized and solved to obtain the cylinder group G j When the position is missing, the remaining cylinders will redistribute the thrust of the partition

[0070] The beneficial effects of the present invention are:

[0071] The present invention provides a method for calculating the propulsion force redistribution of a shield propulsion system in a push-and-splice synchronous mode, which realizes the thrust redistribution in the push-and-splice mode taking into account the shield posture, different partition modes of the propulsion system, and different vacancy groups, and provides a theoretical basis for the design of the partition form of the propulsion system and the calculation of the redistributed thrust in the push-and-splice synchronous mode of the shield propulsion system. BRIEF DESCRIPTION OF THE DRAWINGS

[0072] Figure 1 A flowchart of a method for calculating propulsion force redistribution of a shield propulsion system in a push-and-splice synchronization mode provided by an embodiment of the present invention;

[0073] Figure 2 A zoning layout diagram of the hydraulic cylinders of a shield propulsion system according to a method for calculating propulsion force redistribution of a shield propulsion system in a push-and-splice synchronization mode provided by an embodiment of the present invention;

[0074] Figure 3 A schematic diagram of the multi-step prediction results of the shield tunneling posture of a shield propulsion system propulsion force redistribution calculation method in a push-and-splice synchronization mode provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0075] The present invention will be further described below with reference to the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it. The embodiments of the present invention are not limited thereto.

[0076] Example 1

[0077] like Figure 1 As shown, a method for calculating propulsion force redistribution of a shield propulsion system in a push-and-splice synchronous mode includes the following steps:

[0078] S1: Obtain historical shield posture information based on the shield guidance system;

[0079] S2: Determine the shield posture change matrix;

[0080] S3: Determine the structural parameters of the shield propulsion system and the segment structure parameters;

[0081] S4: Obtain the thrust of all cylinders in the push-and-spin alternating mode;

[0082] S5: Establish the force transfer equation of shield propulsion system;

[0083] S6: Establishing the partition thrust redistribution equation in the push-and-spin synchronization mode;

[0084] S7: Optimize and solve the partitioned thrust according to the thrust redistribution optimization principle to obtain the redistributed thrust of the remaining cylinders when some cylinder groups are missing.

[0085] Historical shield posture information in S1, specifically including: shield posture vector q = [xyz ψ θ φ] T ;

[0086] Among them, (x, y, z) represents the position coordinates of the center of the spherical joint distribution circle in front of the shield machine's propulsion cylinder; (ψ, θ, φ) represents the three attitude angles of the shield machine: roll angle, pitch angle and yaw angle.

[0087] The calculation formula of shield posture change matrix in S2 is:

[0088]

[0089] in, and Represent the shield's posture matrix and position vector respectively, and the calculation formula is:

[0090]

[0091] Among them, c represents the cosine function cos; s represents the sine function sin.

[0092] The shield propulsion system structural parameters and segment structural parameters in S3 include: Determine the shield propulsion system parameters based on engineering data: Propulsion cylinder rear ball joint B i Coordinate, i=1,2,3,...n; n is the total number of thrust cylinders; the pipe segment is divided into blocks.

[0093] The propulsion force vector of all cylinder propulsion forces of the shield propulsion system in S4 is F d =[F1 F2 … F n ] T .

[0094] The force transfer equation of the shield propulsion system in S5 is obtained based on the static equilibrium characteristics of the shield machine and the principle of virtual work; the force transfer equation of the shield propulsion system is:

[0095] J T F d +F e =0 (23)

[0096] Among them, F e is the equivalent load received during shield tunneling; J is the Jacobian matrix of shield propulsion velocity, and its calculation formula is as follows:

[0097]

[0098] in, A u i is the unit direction vector of the i-th propulsion cylinder, and its calculation formula is:

[0099]

[0100] Definition J T F d The target equivalent driving force for the shield propulsion system Right now

[0101]

[0102] Where G = J T The force Jacobian matrix of the shield propulsion mechanism is expressed as

[0103] G=[G1 G2 … G n ] (27)

[0104] S6 establishes the partition thrust redistribution equation in the push-and-spin synchronization mode, which is expressed as:

[0105]

[0106] in, It is defined as the reconstructed force Jacobian matrix of the shield propulsion mechanism, indicating that there is a missing cylinder group G in the shield propulsion system. j The force Jacobian matrix when , is the thrust vector of the redistributed cylinder that needs to be solved; The specific form is

[0107]

[0108] j is the missing cylinder group G j The corresponding segment model to be assembled is

[0109] j={F,L1,L2,B1,B2,…,BN r -3}

[0110] Among them, N r is the total number of segments in a ring;

[0111] Assume that cylinder group G is missing j The set of propulsion cylinder numbers in

[0112] G j ={j1,j2,…,j m} (30)

[0113] Where m is the missing cylinder group G j The number of oil cylinders included;

[0114] Due to the absence of cylinder group G j The thrust of the cylinder in the reconstructed force Jacobian matrix is ​​0, so the columns corresponding to the multiplication of the thrust of the missing cylinder group should be 6-dimensional 0 vectors, that is,

[0115]

[0116] Assume that the number of shield propulsion system partitions is N (3≤N≤n), and name the different partitions P1, P2, ..., PN in sequence. Assume that there are n partitions in the kth partition, that is, partition Pk. k propulsion cylinders, and the cylinder numbers are n in this partition k The thrust of the propulsion cylinders is the same, so there is

[0117]

[0118] in,

[0119]

[0120] The thrust redistribution equation of the shield propulsion system in the push-and-spin synchronization mode is expressed as follows:

[0121]

[0122] Among them, H Gj is the Jacobian matrix of the shield propulsion mechanism partition, H Gj =[H P1 H P2 … H PN ], Redistribute the thrust of all partitions to form a thrust vector.

[0123] S7 specifically includes:

[0124] According to the number of different partitions N of the propulsion system, the optimization problem of shield redistribution thrust is discussed in different situations:

[0125] (1) When 3≤N<6

[0126] At this time, formula (35) is an overdetermined equation, and the least square method is used to obtain an approximate solution. The optimization problem is described as:

[0127]

[0128] Among them, F max is the hydraulic cylinder thrust threshold;

[0129] (2) When N = 6

[0130] At this time, formula (35) is a well-posed equation, and the optimization problem is described as:

[0131]

[0132] (3) When 6 < N ≤ n

[0133] At this time, formula (35) is an underdetermined equation, so that there are infinite solutions for the redistribution of the partition thrust; in order to avoid excessive thrust waste and even damage to the shield propulsion mechanism, the force optimization of the propulsion synchronization redistribution partition thrust is carried out by using the force two-norm minimization method, and the optimization problem is described as:

[0134]

[0135] In the formula, W is an N-order unit matrix;

[0136] According to the partition of the shield propulsion mechanism, formula (36), (37) or (38) is optimized and solved, so that the oil cylinder group G j When some oil cylinder groups are missing, the redistribution of the remaining oil cylinder groups

[0137] Example 2

[0138] A shield propulsion system propulsion force redistribution calculation method in a push-assemble synchronization mode, comprising the following steps:

[0139] S1: obtaining historical shield pose information according to a shield guiding system;

[0140] S2: determining a shield pose change matrix;

[0141] S3: determining shield propulsion system structure parameters and segment structure parameters;

[0142] S4: obtaining all oil cylinder thrusts in a push-assemble alternating mode;

[0143] S5: establishing a shield propulsion system force transmission equation;

[0144] S6: establishing a partition thrust redistribution equation in a push-assemble synchronization mode;

[0145] S7: optimizing and solving the partition thrust according to the thrust redistribution optimization principle, so as to obtain the redistribution thrust of the remaining oil cylinder groups when some oil cylinder groups are missing.

[0146] The shield guiding system in step one obtains historical shield pose information, including a shield pose vector q = [x y z ψ θ φ] TThe above parameters are collected and obtained through the shield machine guidance system; in this example, q0 = [2.5m 0m 0m 2°0°0°] T .

[0147] The shield posture change matrix in step 2 is determined according to formula (1):

[0148]

[0149] According to formulas (2) and (3), and Determined

[0150]

[0151] The structural parameters of the shield propulsion system in step 3 are determined based on engineering data: the propulsion cylinder rear spherical joint coordinate Bi is determined by the propulsion system cylinder layout plan. The shield propulsion system adopts a 28-double cylinder layout and a six-zone control mode (N=6). The segment adopts a 9+1 block mode, namely "7B(38.571°)+2L(39.171°)+F(11.657°)", such as Figure 2 shown.

[0152] In step 4, the propulsion force vector composed of all cylinder thrusts in the push-and-spin alternating mode is determined as F d =1.6×10 6 ×I 56 , I 56 Represents a 56-dimensional column vector whose components are all 1.

[0153] The calculation results of the shield propulsion system force transfer equation in step 5 are as follows:

[0154]

[0155] The determination in step 6 then includes the following equations for partition thrust redistribution in the push-pull synchronization mode:

[0156] Assume that the cylinder group corresponding to the B4 segment in the propulsion system is missing, that is, the missing cylinder group is numbered G. B4 , and the cylinder number in the missing cylinder group is G B4 ={54,55,56,1,2,3}.

[0157]

[0158] Among them, the solution is

[0159]

[0160] The optimization solution for redistributing the partition thrust in step seven includes:

[0161] The number of shield propulsion system partitions N = 6, so the formula (18) is used to optimize the solution The thrust calculation result of redistribution partition is

[0162]

[0163] Figure 3 A schematic diagram of the shield machine's thrust redistribution calculation results is provided. This shows that the proposed method for redistributing thrust of a shield propulsion system in the push-and-splice synchronization mode can accurately and reasonably distribute the thrust of the remaining cylinders when a cylinder group is missing, ensuring that the equivalent driving force of the front and rear cylinders is consistent, allowing the shield machine to continue advancing along its intended trajectory.

[0164] Those skilled in the art will understand that the accompanying drawings are merely schematic diagrams of an embodiment, and the processes in the accompanying drawings are not necessarily required to implement the present invention.

Claims

1. A method for calculating propulsion force redistribution of a shield propulsion system in a push-and-spin synchronous mode, characterized in that: The following steps are involved: S1: Obtain historical shield posture information based on the shield guidance system; S2: Determine the shield posture change matrix; S3: Determine the structural parameters of the shield propulsion system and the segment structure parameters; S4: Obtain the thrust of all cylinders in the push-and-spin alternating mode; S5: Establish the force transfer equation of shield propulsion system; S6: Establishing the partition thrust redistribution equation in the push-and-spin synchronization mode; S7: Optimize and solve the partitioned thrust according to the thrust redistribution optimization principle to obtain the redistributed thrust of the remaining cylinders when some cylinder groups are missing; The historical shield posture information in S1 specifically includes: shield posture vector q = [xyz ψ θ φ] T ; Where (x, y, z) represents the position coordinates of the center of the spherical joint distribution circle in front of the shield machine's propulsion cylinder; (ψ, θ, φ) represents the three attitude angles of the shield machine: roll angle, pitch angle and yaw angle; Among them, S6 is specifically: The partition thrust redistribution equation in the push-and-spin synchronization mode is established and expressed as follows: in, It is defined as the reconstructed force Jacobian matrix of the shield propulsion mechanism, indicating that there is a missing cylinder group G in the shield propulsion system. j The force Jacobian matrix when , is the thrust vector of the redistributed cylinder that needs to be solved; The specific form is j is the missing cylinder group G j The corresponding segment model to be assembled is j={F,L1,L2,B1,B2,…,BN r -3} Among them, N r is the total number of segments in a ring; Assume that cylinder group G is missing j The set of propulsion cylinder numbers in G j ={j1,j2,…,j m } (3) Where m is the missing cylinder group G j The number of oil cylinders included; Due to the absence of cylinder group G j The thrust of the cylinder in the reconstructed force Jacobian matrix is ​​0, so the columns corresponding to the multiplication of the thrust of the missing cylinder group should be 6-dimensional 0 vectors, that is, [G j1 …G jm ]=[0] 6×m (4) Assume that the number of shield propulsion system partitions is N (3≤N≤n), and name the different partitions P1, P2, ..., PN in sequence. Assume that there are n partitions in the kth partition, that is, partition Pk. k propulsion cylinders, and the cylinder numbers are n in this partition k The thrust of the propulsion cylinders is the same, so there is in, The thrust redistribution equation of the shield propulsion system in the push-and-spin synchronization mode is expressed as follows: Among them, H Gj is the Jacobian matrix of the shield propulsion mechanism partition, H Gj =[H P1 H P2 …H PN ], Redistribute the thrust of all partitions to form a thrust vector.

2. The method for calculating propulsion force redistribution of a shield propulsion system in a push-and-splice synchronous mode according to claim 1 is characterized in that: The calculation formula of shield posture change matrix in S2 is: in, and Represent the shield's posture matrix and position vector respectively, and the calculation formula is: Among them, c represents the cosine function cos; s represents the sine function sin.

3. The method for calculating propulsion force redistribution of a shield propulsion system in a push-and-spin synchronous mode according to claim 1 is characterized in that: The shield propulsion system structural parameters and segment structural parameters in S3 include: Determine the shield propulsion system parameters based on engineering data: Propulsion cylinder rear ball joint B i Coordinate, i=1,2,3,...n; n is the total number of thrust cylinders; the pipe segment is divided into blocks.

4. The method for calculating propulsion force redistribution of a shield propulsion system in a push-and-spin synchronous mode according to claim 1 is characterized in that: The propulsion force vector of all cylinder propulsion forces of the shield propulsion system in S4 is F d =[F1 F2 … F n ] T .

5. The method for calculating propulsion force redistribution of a shield propulsion system in a push-and-spin synchronous mode according to claim 1 is characterized in that: The force transfer equation of the shield propulsion system in S5 is obtained based on the static equilibrium characteristics of the shield machine and the principle of virtual work; the force transfer equation of the shield propulsion system is: J T F d +F e =0 (12) Among them, F e is the equivalent load received during shield tunneling; J is the Jacobian matrix of shield propulsion velocity, and its calculation formula is as follows: in, A u i is the unit direction vector of the i-th propulsion cylinder, and its calculation formula is: Definition J T F d The target equivalent driving force for the shield propulsion system Right now Where G = J T The force Jacobian matrix of the shield propulsion mechanism is expressed as G=[G1 G2 … G n ] (16)。 6. The method for calculating propulsion force redistribution of a shield propulsion system in a push-and-spin synchronous mode according to claim 1 is characterized in that: S7 specifically includes: According to the number of different partitions N of the propulsion system, the optimization problem of shield redistribution thrust is discussed in different situations: (1) When 3≤N<6 At this time, formula (8) is an overdetermined equation, and the least squares method is used to obtain an approximate solution. The optimization problem is described as: Among them, F max is the hydraulic cylinder thrust threshold; (2) When N = 6 At this time, formula (8) is a well-posed equation, and the optimization problem is described as: (3) When 6<N≤n At this time, formula (8) is an underdetermined equation, which means that there are countless solutions for the thrust of the redistributed partitions. In order to avoid excessive thrust waste or even damage to the shield propulsion mechanism, the force of the synchronous redistributed partition thrust is optimized by minimizing the two-norm force. The optimization problem is described as: Where W is the N-order unit matrix; According to the shield propulsion mechanism partition situation, the formula (17), (18) or (19) is optimized and solved, that is, the cylinder group G is obtained j When the position is missing, the remaining cylinders will redistribute the thrust of the partition

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