Moment compensation-based balanced distribution method for intelligent tunneling oil pressure of shield tunneling machine

Abstract

Disclosed is a moment compensation-based balanced distribution method for the intelligent tunneling oil pressure of a shield tunneling machine. The method comprises: firstly establishing a space rectangular coordinate system, and determining a first target deviation-correction moment Mx, a second target deviation-correction moment My, and a required target total thrust Ft; then, compensating for the first target deviation-correction moment Mx and the second target deviation-correction moment My and then converting same into corresponding corrected moments; by means of regarding as adjustable the oil pressure of each oil cylinder group which is uniformly distributed on a circumference, and by means of using an obliquely-truncated cylinder mathematical model, performing balanced distribution on the oil pressure of each oil cylinder group under the condition that oil pressure vector endpoints of the oil cylinder groups are coplanar; and then taking as a final partition oil pressure the mean value of the oil pressures which are distributed to all the oil cylinder groups in a partition. Thus, an optimal distribution result can be accurately and efficiently obtained, and a technical foundation is provided for automatic / intelligent control over the attitude of a shield tunneling machine. The distribution result conforms to the balance in a geometric space while meeting distribution targets, thereby facilitating the protection of segment rings during tunneling construction.

Description

Intelligent tunneling oil pressure balance distribution method for shield machine based on torque compensation Technical Field

[0001] The present invention relates to the technical field of shield machine control, and in particular to a shield machine intelligent tunneling oil pressure balancing distribution method based on moment compensation. Background Art

[0002] A shield machine is a tunnel boring machine that uses the shield method. Its basic working principle is that a cylindrical steel component is pushed forward along the axis of the tunnel while excavating the soil, and supporting segments are laid during the excavation process. The circumference of the shield body of the shield machine is usually evenly equipped with several thrust cylinder groups. The support shoe at the top of the piston rod of the thrust cylinder group is against the end face of the pipe ring, and the shield machine is pushed in the reverse direction of excavation by slowly extending the piston rod. Several cylinder groups arranged at equal intervals in the circumference are usually divided into multiple zones with independently adjustable oil pressure, and the number of cylinder groups in each zone can vary. According to engineering requirements, a single group or multiple groups of adjacent thrust cylinder groups are connected in parallel as a zone, and the oil pressure is uniformly controlled by the same valve group. Therefore, the oil pressure of each cylinder pair in the same zone should be the same.

[0003] In recent years, the equipment and construction methods used in shield tunneling projects have been developing towards automation and intelligence. A crucial aspect of this is the automatic control of the shield machine's tunneling posture. To achieve the desired posture or planned alignment, the shield machine's intelligent tunneling system can sense the machine's operating environment and parameters and recommend a target total thrust and target corrective torque for correcting the machine's posture. This target value is then decomposed into a target oil pressure for each zone. By adjusting the zone oil pressure of each thrust cylinder in the shield machine, the intensity and direction of the corrective torque are adjusted, thereby achieving the desired posture correction. However, under the same total thrust and corrective torque conditions, numerous combinations of zone oil pressure values ​​are possible. In engineering practice, this control is typically performed by the operator based on their experience and habits. Different operators have different operating techniques, resulting in significant variations in the resulting zone oil pressure distribution under the same conditions, making it difficult to provide a useful reference for the development of automatic / intelligent shield machine posture control technology.

[0004] Furthermore, the distribution of oil pressure also needs to take into account the requirement for balance. Figure 1(a) shows irregular zone oil pressure distribution, while Figure 1(b) shows balanced oil pressure distribution. Based on actual construction practices, the industry generally believes that the smaller the difference in oil pressure between adjacent zones, the smaller the bending moment on the segment at the zone's junction, which in turn reduces segment damage. Therefore, under the premise of the same total thrust and corrective torque, the more balanced the oil pressure in each zone, the better. That is, the distribution result is optimal if the gradient of the zone oil pressure changes consistently along the target corrective torque.

[0005] A shield machine has three degrees of freedom: pitch, yaw, and fore-aft translation. However, the number of thrust cylinders is far greater than three, leading to overdrive. To achieve the shield machine's kinematic mechanics, it's necessary to coordinate and distribute the oil pressure of the redundant thrust cylinders. This problem, similar to redundancy issues encountered in aviation, navigation, and automotive fields, is known as the control allocation problem. Currently, the main algorithms for solving the control allocation problem include:

[0006] (1) Explicit combination method: The explicit combination method uses a pre-designed combination method to produce a single control effect by coordinating multiple actuator structures. This method is easy to implement in engineering and is suitable for overdrive systems with obvious and limited combination methods. However, it cannot effectively handle constraints or optimize performance. When an actuator fails, the designed combination scheme will fail. It has no adaptive redistribution capability and is not suitable for systems with high redundancy.

[0007] This method requires pre-setting combinations to produce a single control action. However, the thrust of a shield machine is continuous within the feasible range, the corrective torque is also continuous within the range, and the corresponding oil pressure changes in each cylinder are also stable and continuous. Using the "explicit combination method" it is difficult to design countless multi-cylinder oil pressure combinations within the feasible domain and achieve continuously changing target thrust and torque. Therefore, the explicit combination method is not suitable for solving the problem of zoned oil pressure distribution in shield machines.

[0008] (2) Cascade Chain Method: Assuming the system's actuators are hierarchical, the core idea of ​​the cascade chain control allocation method is to quickly activate the next-level actuator to compensate for the required control quantity if the previous-level actuator is saturated. The cascade chain control allocation algorithm has the advantages of simple engineering implementation, fast allocation speed, and reliable use, but it also has the problem of actuator saturation.

[0009] This method can easily lead to the oil pressure / thrust of some actuators (thrust cylinders) that are activated first reaching their limit, which is unacceptable in shield construction. Therefore, the series chain method is not suitable for solving the problem of zoned oil pressure distribution in shield machines.

[0010] (3) Direct allocation method: The direct allocation method was proposed by Duaham and is a geometric algorithm. In the process, a control pseudo-instruction W is given and a suitable control input *R is obtained so that the pseudo-control input W*=LR* has the largest amplitude in the W direction.

[0011] Bodson transforms direct assignment into the form of solving an optimization problem, by giving ɑ, R*, and solving:

[0012] The direct allocation algorithm seeks to maximize the amplitude of the allocation result in the desired direction, and needs to use the optimization problem solving method to solve it, which is relatively cumbersome and not accurate enough.

[0013] (4) Generalized inverse allocation method: The generalized inverse control allocation algorithm introduces the minimum norm constraint, which can be expressed as The explicit solution of this formula is R = L + W, where L + =L T (LL T ) -1 is the pseudo-inverse matrix of L.

[0014] This method solves the movement amount of each actuator through generalized inverse, and pursues the minimum comprehensive output of the actuator. However, for the case of uneven distribution of the shield machine's propulsion cylinders - when the lever arms differ greatly, it can ensure that the distribution results meet the total thrust and torque requirements, but the maximum partition oil pressure may be adjacent to the minimum partition oil pressure, and the distribution results cannot be guaranteed to be balanced, which affects the force on the segments and poses potential risks.

[0015] Among traditional control allocation algorithms, in addition to the ones listed above, there is also a fixed-point iterative algorithm proposed by Burken for solving weighted optimal control allocation problems. This algorithm is similar to the iterative algorithm of gradient search and has global convergence, but if unreachable instructions are given, the algorithm may be slow. In addition, there are interior point algorithms for solving quadratic programming and effective set algorithms for solving small to medium-sized quadratic programming problems. Both interior point algorithms and effective set algorithms transform the control allocation problem into a quadratic programming problem, and their purpose is to solve the optimal solution that meets the objective function and constraints. Using quadratic programming to solve the control allocation problem generally seeks to minimize the objective function under the constraints. This approach can achieve oil pressure distribution in each partition that meets the target total thrust and corrective torque, but it cannot guarantee a balanced distribution result.

[0016] Summary of the Invention

[0017] The present invention is made to solve the above problems, and its purpose is to provide a shield machine intelligent tunneling oil pressure balancing distribution method based on torque compensation.

[0018] To achieve the above objectives, the present invention provides the following technical solutions:

[0019] A method for balancing oil pressure during intelligent tunneling of a shield machine based on torque compensation is disclosed. The propulsion system of the shield machine includes a plurality of cylinder groups uniformly distributed along the circumference within an installation plane. The thrust direction of each cylinder group is perpendicular to the installation plane. All cylinder groups are divided into multiple partitions, including:

[0020] Step S1: First determine the total number of cylinder groups n, the number of partitions m, and the number of cylinder groups in each partition n. jAnd the radius R of the circle where the cylinder group is located, then take the center of the circle as the origin O, establish the spatial rectangular coordinate system O-xyz and make the x-axis and y-axis located in the installation plane, and further determine the first target correction torque M of all partitions in the x direction relative to the origin O x and the second target correcting moment M in the y direction y And the target total thrust F that the propulsion system needs to achieve t ;

[0021] Step S2: Calculate the first target correction torque M according to the total number of cylinder groups, the central angle of each cylinder group, the number of partitions, and the number of cylinder groups in each partition. x and the second target correcting torque M y The arrival rate of the target is used to determine the corresponding correction coefficient, and the correction coefficient is used to adjust the first target correction torque M x and the second target correcting torque M y Compensate and get the first correction torque M x_corrected and the second correction moment M y_corrected ;

[0022] Step S3: Using the first correction moment M x_corrected , the second correction moment M y_corrected and the target total thrust F t To achieve the distribution goal, the mathematical model of the truncated cylinder is used to evenly distribute the oil pressure of each cylinder group under the condition that the end points of the oil pressure vectors of each cylinder group are coplanar.

[0023] Step S4: Calculate the average of the oil pressures allocated to all cylinder groups in each partition as the corresponding partition oil pressure to obtain the final partition oil pressure balanced distribution result.

[0024] Furthermore, in step S1, the positive direction of the z-axis of the spatial rectangular coordinate system O-xyz is perpendicular to the installation plane from the origin O to the shield machine's excavation direction, the positive direction of the y-axis is from the origin O in the installation plane to the shield machine's zenith direction, and the positive direction of the x-axis is determined according to the right-hand rule.

[0025] Furthermore, in step S2, the first target correction torque M x The corresponding first torque arrival rate Ra x The calculation formula is: The corresponding correction factor is 1 / Ra x , the first correction torque after compensation The second target correcting torque M y The corresponding second torque arrival rate Ra y The calculation formula is: The corresponding correction factor is 1 / Ra y , the second correction torque after compensation Among them, θ i is the central angle corresponding to the center of the i-th cylinder group, n j is the number of cylinder groups in the jth partition.

[0026] Furthermore, step S3 includes the following sub-steps:

[0027] Step S3-1: Establish a mathematical model of the truncated cylinder. Correspond the geometric constraints that any generatrix length of the truncated cylinder should meet with the oil pressure vector length of the cylinder group. It is deduced that when the end points of the oil pressure vectors of each cylinder group are coplanar, the constraint condition that the oil pressure of each cylinder group should meet is: P i =P b +R·cos(θ i -α)·tanβ, where P i is the oil pressure of the i-th cylinder group; the reference oil pressure P b is a virtual vector that is consistent with the direction of each oil pressure vector, with its starting point at the origin O and its end point at the target plane where the end points of each oil pressure vector are located; θ i is the central angle corresponding to the center of the i-th cylinder group, α is the direction angle of the projection of the major semi-axis of the elliptical oblique section in the oblique cylinder mathematical model on the installation plane, and tanβ is the inclination of the target plane where the end point of the oil pressure vector of each cylinder group is located;

[0028] Step S3-2: The sum of the thrusts of all cylinder groups is equal to the target total thrust F t The reference oil pressure is obtained by the equivalent relationship Where K is the conversion coefficient between oil pressure and thrust;

[0029] Step S3-2: According to the first correction moment M x_corrected , the second correction moment M y_corrected Determine the correction torque Then, the direction angle of the projection of the major axis of the elliptical oblique section in the mathematical model of the oblique cylinder in the installation plane and the correction moment M are used to correct the deviation. t_corrected The corresponding relationship between the direction angles is obtained

[0030] Step S3-3: The sum of the thrust moments of each cylinder group in the α direction is equal to the correction torque M t_corrected The equivalent relationship is obtained

[0031] Step S3-4, P b , α, and tanβ are substituted into the constraints of step S3-1 to obtain the equation for the variable θ. i The formula for calculating the oil pressure of the cylinder group is:

[0032] Substitute the central angle θ corresponding to each cylinder group in turn i , calculate the oil pressure allocated to each cylinder group respectively.

[0033] Furthermore, K = F max / P max , F max The oil pressure of a single cylinder group reaches the maximum value P max The corresponding maximum thrust.

[0034] Furthermore, in step S4, the calculation formula of the zone oil pressure is: Where, P zone_j is the oil pressure of the jth partition, P i is the oil pressure of the i-th cylinder group, n j is the number of cylinder groups in the jth partition.

[0035] The present invention has the following beneficial effects:

[0036] 1. The shield machine intelligent tunneling oil pressure balancing distribution method based on torque compensation of the present invention is to achieve the first target deviation correction torque M x and the second target correcting torque M y After compensation, it is converted into the corresponding correction torque. The oil pressure of each cylinder group evenly distributed on the circumference is regarded as adjustable to distribute the oil pressure, which simplifies the distribution conditions. The average of the oil pressures allocated to all cylinder groups in the partition is then used as the final partition oil pressure, which can obtain the distribution result simply and efficiently.

[0037] 2. The invention discloses a shield machine intelligent tunneling oil pressure balancing distribution method based on torque compensation, which distributes the oil pressure of the m partitions of the shield machine to meet the given target total thrust F. t , the first target correction torque M x And the second target correction torque M y At the same time, the oil pressure distribution of the m partitions conforms to the balance in the geometric space. The oil pressure gradient of each partition after distribution is uniform, and the difference between the oil pressures of adjacent partitions is smaller, which can effectively reduce the bending moment of the pipe segments at the junction of the partitions, thereby reducing the damage to the pipe segments and facilitating the protection of the pipe ring during tunneling construction.

[0038] 3. The torque-compensated shield machine intelligent tunneling oil pressure balancing distribution method of the present invention accurately and efficiently obtains the optimal oil pressure distribution result through theoretical calculation, laying a technical foundation for the automatic / intelligent control of the shield machine posture. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] FIG1 is a schematic diagram of oil pressure distribution by zones in an embodiment of the present invention;

[0040] FIG2 is a schematic diagram of the distribution of the shield machine propulsion cylinder group in an embodiment of the present invention;

[0041] 3 is a flow chart of oil pressure balancing distribution in intelligent tunneling zones of a shield machine based on moment compensation in an embodiment of the present invention;

[0042] FIG4 is a schematic diagram of a mathematical model of a truncated cylinder in an embodiment of the present invention;

[0043] FIG5 is a simulation diagram of the oil pressure vector spatial distribution in an embodiment of the present invention;

[0044] FIG6 is a simulation diagram of the oil pressure distribution effect in an embodiment of the present invention. DETAILED DESCRIPTION

[0045] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the following embodiments and the accompanying drawings specifically illustrate the shield machine intelligent tunneling oil pressure balancing distribution method based on torque compensation of the present invention.

[0046] <Example>

[0047] As shown in Figures 1 and 2, in this embodiment, the propulsion system of the shield machine includes a plurality of propulsion cylinder groups uniformly distributed along the circumferential direction within the installation plane. The thrust direction of each cylinder group is perpendicular to the installation plane, and all cylinder groups are divided into multiple partitions.

[0048] As shown in FIG3 , the shield machine intelligent tunneling oil pressure balancing distribution method based on torque compensation of this embodiment includes the following steps:

[0049] Step S1: First determine the total number of cylinder groups n, the number of partitions m, and the number of cylinder groups in each partition n. j And the radius R of the circle where the cylinder group is located, then take the center of the circle as the origin O, establish the spatial rectangular coordinate system O-xyz and make the x-axis and y-axis located in the installation plane, and further determine the first target correction torque M of all partitions in the x direction relative to the origin O x and the second target correcting moment M in the y direction y And the target total thrust F that the propulsion system needs to achieve t ;

[0050] Step S2: Calculate the first target correction torque M according to the total number of cylinder groups, the central angle of each cylinder group, the number of partitions, and the number of cylinder groups in each partition. x and the second target correcting torque M y The arrival rate of the target is used to determine the corresponding correction coefficient, and the correction coefficient is used to adjust the first target correction torque M x and the second target correcting torque M y Compensate and get the first correction torque M x_corrected and the second correction moment M y_corrected ;

[0051] Step S3: Using the first correction moment M x_corrected , the second correction moment M y_corrected and the target total thrust F t To achieve the distribution goal, the mathematical model of the truncated cylinder is used to evenly distribute the oil pressure of each cylinder group under the condition that the end points of the oil pressure vectors of each cylinder group are coplanar.

[0052] Step S4: Calculate the average of the oil pressures allocated to all cylinder groups in each partition as the corresponding partition oil pressure to obtain the final partition oil pressure balanced distribution result.

[0053] Furthermore, in step S1, the positive direction of the z-axis in the spatial rectangular coordinate system O-xyz is perpendicular to the installation plane from the origin O to the shield machine's excavation direction, the positive direction of the y-axis is from the origin O in the installation plane to the shield machine's zenith direction, and the x-axis direction is determined according to the right-hand rule.

[0054] Specifically, in this embodiment, the center O1 of the circle containing the partition's equivalent force points is used as the origin O, and the horizontal and vertical corrective torques are used to describe the torques generated by the thrust cylinders. From the perspective of an observer facing the tunneling direction, the y-axis points vertically upward from the center O1, and the x-axis points horizontally to the right, perpendicular to the y-axis.

[0055] As shown in Figures 1 and 2, it is assumed that the radius of the circle where each cylinder group (root center) in the shield machine is located is R; the target correction torques expected to be achieved by all cylinder groups in the horizontal direction (i.e., x direction) and the vertical direction (i.e., y direction) are M respectively. x 、M y .

[0056] Furthermore, in step S2, the first target correction torque M x The corresponding first torque arrival rate Ra x The calculation formula is: The corresponding correction factor is 1 / Ra x , the first correction torque after compensation The second target correcting torque M y The corresponding second torque arrival rate Ra y The calculation formula is: The corresponding correction factor is 1 / Ra y , the second correction torque after compensation Among them, θ i is the central angle corresponding to the center of the i-th cylinder group, n j is the number of cylinder groups in the jth partition.

[0057] Furthermore, step S3 includes the following sub-steps:

[0058] Step S3-1: Establish a mathematical model of a truncated cylinder. Correspond the geometric constraints that any generatrix length of the truncated cylinder should meet to the oil pressure vector length of the cylinder group. Derived, when the end points of the oil pressure vectors of each cylinder group are coplanar, the constraints that the oil pressure of each cylinder group should meet are obtained.

[0059] Specifically, as shown in Figure 1(b) and Figure 4, the circle O1 (located in the installation plane) where the center of each cylinder group of the shield machine is located, the oil pressure vector of each cylinder group, and the ellipse O2 (located in the target plane) formed by the vector vertex can be abstracted as a truncated cylinder. The highest point of the truncated cylinder is denoted as C. The generatrix passing through point C intersects with the circle O1 at point B. Then the plane O1O2CB is the symmetry plane of the truncated cylinder. The angle between this plane and the positive direction of the X-axis is denoted as α. Then α is the direction angle of the projection O1B of the major semi-axis O2C of the elliptical oblique section in the mathematical model of this truncated cylinder in the installation plane. Any generatrix AG intersects with the circle O1 at point A and intersects with the elliptical surface at point G. The angle between the straight line O1A and the positive direction of the X-axis is denoted as θ i The angle between the elliptical surface and the circular surface of the truncated cylinder is denoted as β.

[0060] From this, we can get the corresponding relationship between the mathematical model of the oblique truncated cylinder and the oil pressure vector distribution model of each partition: the oil pressure vector length of each cylinder group is equal to the length of the corresponding position busbar, and the target total thrust F t The magnitude is equal to the sum of the thrusts of each partition, that is, the sum of the thrusts of all cylinder groups. i is the central angle corresponding to the center of the i-th cylinder group, and tanβ is the inclination of the target plane where the end point of the oil pressure vector of each cylinder group is located.

[0061] Taking any busbar AG as an example, we deduce the geometric constraints that the busbar length complies with when its vertices are coplanar. Figure 4 shows that |AG| = |AD| + |DG|, where |AD| = |O1O2|. This shows that if the line segment O1O2 is known, the length of line segment DG is sufficient to calculate the length of AG.

[0062] Since plane O1O2CB is perpendicular to the circular and elliptical end faces of the obliquely truncated cylinder, and planes AHFG, O1O2CB, and the plane containing circle O1 are perpendicular to each other, quadrilateral AHFG is a rectangle. Furthermore, quadrilateral DEFG is also a rectangle, so |DG| = |EF|. The length of line segment EF can be found within △EO2F using the formula EF| = |O2E|·tanβ. In rectangle O1O2EH, |O2E| = |O1H|, and the length of line segment O1H can be found within △O1HA using the formula |O1H| = |O1A|·cos(θ i -α) solution.

[0063] Therefore, it can be deduced that the geometric constraint that any generatrix length AG in the mathematical model of the oblique cylinder should satisfy is:i =|AG|=|O1O2|+R·cos(θ i -α)·tanβ.

[0064] The geometric constraints that the truncated cylinder generatrix length in the truncated cylinder mathematical model should meet are mapped to the oil pressure vector distribution model of each cylinder group. It is deduced that when the end points of the oil pressure vectors of each cylinder group are coplanar, the oil pressure P of the i-th cylinder group is i The constraints that must be met are:

[0065] Among them, Q i =R·cos(θ i -α),

[0066] Where, P i is the oil pressure of the i-th cylinder group; the reference oil pressure P b It is a virtual vector that is consistent with the direction of each oil pressure vector. Its starting point is located at the origin O, and its end point is located at the target plane where the end point of each oil pressure vector is located.

[0067] Step S3-2: The sum of the thrusts of all cylinder groups is equal to the target total thrust F t The reference oil pressure is obtained by the equivalent relationship of .

[0068] Specifically, assuming that the thrust corresponding to the i-th cylinder group is F i ,but:

[0069] Since the cylinder groups are evenly distributed along the circumference, it can be deduced that:

[0070] Therefore, F t =P b nK, solve for the reference oil pressure Where K is the conversion coefficient between oil pressure and thrust.

[0071] Furthermore, K = F max / P max , F max The oil pressure of a single group of cylinders reaches the maximum value P max The conversion factor K is determined according to the actual configuration of the shield machine hydraulic system.

[0072] Step S3-2: According to the first correction moment M x_corrected , the second correction moment M y_corrected Determine the correction torque M t_corrected Then, the direction angle of the projection of the long semi-axis of the elliptical oblique section in the mathematical model of the oblique cylinder on the installation plane and the correction moment M are used to correct the deviation. t_corrected The corresponding relationship between the direction angles is solved to obtain α.

[0073] Specifically, the first correction moment M is known to be x_corrected , the second correction moment M y_corrected Correcting the resultant torque, we can get the corrected resultant torque:

[0074] Since the centers of the cylinder groups are equally spaced along the circumferential direction in the installation plane, the direction angle of the projection O1B of the major axis O2C of the elliptical oblique section in the mathematical model of the oblique cylinder in the installation plane is equal to the direction angle of the correction torque, that is, there is

[0075] Step S3-3: The sum of the thrust moments of each cylinder group in the α direction is equal to the correction torque M t_corrected Solving the equivalent relationship of tanβ gives tanβ.

[0076] Specifically, according to the equivalent relationship, we can get:

[0077] Since the cylinder groups are evenly distributed along the circumference, it can be deduced that: and

[0078] therefore, The solution is

[0079] Step S3-4, P b , α, and tanβ are substituted into the constraints of step S3-1 to obtain the equation for the variable θ. i The formula for calculating the oil pressure of the cylinder group is:

[0080] Substitute the central angle θ corresponding to each cylinder group in turn i , calculate the oil pressure allocated to each cylinder group respectively.

[0081] Furthermore, in step S4, the calculation formula of the zone oil pressure is:

[0082] Where, P zone_j is the oil pressure of the jth partition, P i is the oil pressure of the i-th cylinder group, n j is the number of cylinder groups in the jth partition.

[0083] Finally, the oil pressure values ​​of the m partitions are calculated in sequence according to the partition oil pressure calculation formula, which is the final partition oil pressure balance distribution result.

[0084] To prove that the final distribution result of the shield machine intelligent tunneling oil pressure balance distribution method based on torque compensation can meet the first target correction torque M x, the second target correction torque M y and the target total thrust F t , the following is verified by theoretical deduction:

[0085] (1) Regarding torque

[0086] In step S3, assuming that the oil pressure of each cylinder group is adjustable independently, after the oil pressure of each cylinder group is evenly distributed, the theoretical moments in the x and y directions are:

[0087] However, since the smallest unit that can actually adjust the oil pressure is a zone, the average of the oil pressures of all cylinders in the same zone is used as the oil pressure of the zone. The actual moments in the x and y directions are:

[0088] Then we can get:

[0089] Therefore, in this embodiment, it is assumed that the oil pressure of each cylinder group can be adjusted independently to compensate for the first correction torque Second correction torque As the goal, the oil pressure of each cylinder group is evenly distributed to make M x_target =M x_corrected , M y_target =M y_corrected Then, the average oil pressure allocated to all cylinder groups in the same partition under the assumed conditions is used as the actual partition oil pressure allocated to the partition, and M can be finally achieved. x_act =M x , M y_act =M y .

[0090] It can be proved that the partitioned oil pressure finally distributed by the shield machine intelligent tunneling oil pressure balanced distribution method based on torque compensation of the present invention can meet the given first target correction torque M x and the second target correcting torque M y .

[0091] (2) About total thrust

[0092] In step S4, the average of the oil pressures assigned to all cylinder groups in each partition is used as the corresponding partition oil pressure. The total thrust actually generated is:

[0093] It can be proved that the partitioned oil pressure finally distributed by the shield machine intelligent tunneling oil pressure balanced distribution method based on torque compensation of the present invention can meet the given target total thrust F t .

[0094] To further verify the effectiveness of balanced oil pressure distribution, a simulation experiment was conducted. Taking a 9-meter-class shield machine as an example, the shield machine propulsion system consists of 19 groups of cylinders, each group consisting of two cylinders physically connected to the top of the cylinder telescopic rods via grippers. The oil pressure-to-thrust conversion coefficient for each cylinder group is K = 2*(2000-0) / (35-0), in kN / MPa. The parameters of the 19 groups of cylinders are shown in the table:

[0095] Assume that the number of partitions m = 6, and the number of cylinder groups in each partition is 3, 3, 3, 4, 3, 3, and the number of cylinder groups in the lower partition is 4. t =22489kN, first target correcting moment M x =-13493.4kN·m and the second target correcting torque M y =-17991.2 kN·m as the target value, and the oil pressure distribution is divided into different zones. The distribution results are simulated, and the thrust vector spatial distribution simulation results are shown in Figure 5. The oil pressure values ​​corresponding to the six zones are: 14.70446043, 9.92416454, 5.53585978, 6.14874373, 11.68480322, and 15.54530372, respectively, in MPa.

[0096] The distribution results were verified: the sum of the thrusts of each partition was calculated to be 22489.0 kN, which is equal to the target total thrust. The thrust of each partition was multiplied by the coordinates of the equivalent effective point corresponding to the partition, and the horizontal and vertical correction moments corresponding to the oil pressure distribution results were obtained to be -13493.399999999996 kN·m and 17991.199999999993 kN·m, respectively, which are in line with the target correction moments (the very small error caused by the loss of precision during the computer calculation process can be ignored).

[0097] Set the target total thrust F t = 22489kN. With a radius of 1m, the equivalent force application point of the total thrust circles around the center of the circle where the propulsion cylinder is located. The corresponding corrective torque changes with the equivalent force application point, which can be calculated by the following formula:

[0098] Where ω∈(0,2π), r=1m.

[0099] The total thrust and corrective torque corresponding to each point are used as target values ​​to distribute the oil pressure in different zones. The changes in the total thrust, corrective torque and related quantities corresponding to the distribution results are verified, and the simulation results are shown in Figure 6. It can be seen that the center of force moves along the circumference while the total thrust remains unchanged, and the distribution result meets the target total thrust F tAccording to the distribution results, the torque and target correction torque M are calculated. x 、M y The difference is close to zero, which can meet the thrust distribution requirements.

[0100] In summary, the shield machine intelligent tunneling oil pressure balancing distribution method based on torque compensation of the present invention distributes the oil pressure of each partition under the premise of a given target total thrust and a target correction torque, simplifies the distribution conditions by means of torque compensation, and obtains a single and definite balanced distribution result under the premise of meeting the distribution target, so as to achieve uniform oil pressure gradient in each partition after distribution, which is beneficial to the protection of the pipe ring during tunneling construction. It has strong practicality and high promotion and application value, and can lay a technical foundation for automatic / intelligent control of the shield machine posture.

[0101] The above embodiments are preferred examples of the present invention and are not intended to limit the scope of protection of the present invention.

Claims

1. A shield machine intelligent tunneling oil pressure balancing distribution method based on moment compensation, wherein the propulsion system of the shield machine includes a plurality of cylinder groups evenly distributed along the circumferential direction in the installation plane, the thrust direction of each cylinder group is perpendicular to the installation plane, and all cylinder groups are divided into a plurality of partitions, characterized in that: include: Step S1, first determine the total number of cylinder groups n, the number of partitions m, the number of cylinder groups in each partition, and the radius R of the circle where the cylinder groups are located, then establish a spatial rectangular coordinate system O-xyz with the center of the circle as the origin O and make the x-axis and y-axis located in the installation plane, and further determine the first target correction torque M of all partitions in the x direction relative to the origin O x and the second target correcting moment M in the y direction y And the target total thrust F that the propulsion system needs to achieve t ; Step S2: Calculate the first target deviation correction moment M according to the total number of cylinder groups, the central angle of each cylinder group, the number of partitions, and the number of cylinder groups in each partition. x and the second target correcting moment M y The arrival rate of the first target correction moment M is determined by the correction coefficient. x and the second target correcting moment M y Compensation is performed to obtain the first correction moment M x_corrected and the second correction moment M y_corrected ; Step S3: Using the first correction moment M x_corrected , the second correction moment M y_corrected And the target total thrust F t To achieve the distribution target, the mathematical model of the oblique truncated cylinder is used to evenly distribute the oil pressure of each cylinder group under the condition that the end points of the oil pressure vectors of each cylinder group are coplanar. Step S4: Calculate the average of the oil pressures allocated to all cylinder groups in each partition as the corresponding partition oil pressure to obtain the final partition oil pressure balanced distribution result.

2. The method for balancing oil pressure of intelligent tunneling of a shield machine based on moment compensation according to claim 1 is characterized in that: In step S1, the positive direction of the z-axis of the spatial rectangular coordinate system O-xyz is perpendicular to the installation plane from the origin O to the tunneling direction of the shield machine, the positive direction of the y-axis is from the origin O in the installation plane to the zenith direction of the shield machine, and the positive direction of the x-axis is determined according to the right-hand rule.

3. The method for balancing oil pressure of intelligent tunneling of a shield machine based on moment compensation according to claim 1 is characterized in that: In step S2, the first target correction torque M x The corresponding first torque arrival rate Ra x The calculation formula is: The corresponding correction factor is 1 / Ra x , the first correction torque after compensation The second target correcting moment M y The corresponding second torque arrival rate Ra y The calculation formula is: The corresponding correction factor is 1 / Ra y , the second correction torque after compensation Among them, θ i is the central angle corresponding to the center of the i-th cylinder group, n j is the number of cylinder groups in the jth partition.

4. The method for balancing oil pressure of intelligent tunneling of a shield machine based on moment compensation according to claim 1 is characterized in that: Step S3 includes the following sub-steps: Step S3-1, establish a mathematical model of the truncated cylinder, correspond the geometric constraints that any generatrix length of the truncated cylinder should meet to the oil pressure vector length of the cylinder group, and deduce that when the end points of the oil pressure vectors of each cylinder group are coplanar, the constraint conditions that the oil pressure of each cylinder group should meet are: Where P i is the oil pressure of the i-th cylinder group; the reference oil pressure P b is a virtual vector that is consistent with the direction of each oil pressure vector, with its starting point located at the origin O and its end point located at the target plane where the end points of each oil pressure vector are located; θ i is the central angle corresponding to the center of the i-th cylinder group, α is the direction angle of the projection of the major semi-axis of the elliptical oblique section in the oblique cylinder mathematical model on the installation plane, and tanβ is the inclination of the target plane where the end point of the oil pressure vector of each cylinder group is located; Step S3-2, according to the sum of the thrusts of all cylinder groups being equal to the target total thrust F t The reference oil pressure is obtained by the equivalent relationship In the formula, K is the conversion factor between oil pressure and thrust; Step S3-2, according to the first correction moment M x_corrected , the second correction moment M y_corrected Determine the correction torque Then, the direction angle of the projection of the major semi-axis of the elliptical oblique section in the mathematical model of the oblique cylinder on the installation plane and the correction torque M are used to calculate the t_corrected The direction angle between The corresponding relationship is obtained Step S3-3, according to the sum of the thrust moments of each cylinder group in the α direction is equal to the correction correction moment M t_corrected The equivalent relationship is Step S3-4, P b Substituting α, tanβ into the constraint conditions of step S3-1, we can obtain the i The calculation formula of the oil pressure of the cylinder group is: Substitute the center angle θ corresponding to each cylinder group in turn i , calculate the oil pressure assigned to each cylinder group respectively.

5. The method for balancing oil pressure of intelligent tunneling of a shield machine based on moment compensation according to claim 4 is characterized in that: in, K=F max / P max , F max The oil pressure of a single cylinder group reaches the maximum value P max The maximum thrust corresponding to .

6. The method for balancing oil pressure of intelligent tunneling of a shield machine based on moment compensation according to claim 1 is characterized in that: In step S4, the calculation formula of the zone oil pressure is: Where P zone_j is the oil pressure of the jth partition, P i is the oil pressure of the i-th cylinder group, n j is the number of cylinder groups in the jth partition.

Images