A method for synchronously erecting multiple hydraulic cylinders

Abstract

The application relates to the field of rocket launching, and particularly discloses a synchronous erecting control method for multiple hydraulic cylinders, which comprises a simulation calculation process; a control system discriminates and operates the values of strain flowers A and the values of strain flowers B; the difference range epsilon threshold of the values of strain flowers A and the values of strain flowers B in the same group of erecting oil cylinders in the control system is measured 实测1 , epsilon 实测2 , epsilon 实测N / 2 , epsilon 实测1 , epsilon 实测2 , epsilon 实测N / 2 When the measured absolute value is greater than the epsilon threshold, the control system automatically and real-timely feeds back and controls the erecting oil cylinder. The scheme directly monitors the deformation and stress conditions of the left and right sides of the final erecting arm, and most truly reflects the erecting arm state, and is applicable to different mass center offset errors of different missile types without the need of re-adjustment, so that the adjustment efficiency is improved.

Description

Technical Field

[0001] This invention relates to the field of rocket launch technology, and in particular to a method for synchronous erection control of multiple hydraulic cylinders. Background Technology

[0002] Existing launching equipment typically uses either a single hydraulic cylinder or a double hydraulic cylinder for erection. When using a double hydraulic cylinder, the synchronization of the cylinders must be considered. Current technology for synchronizing double-cylinder erection primarily employs closed-loop PID control. Furthermore, the valve group and control system are customized and designed based on the required synchronization accuracy. The erecting arm also possesses a certain degree of rigidity, which allows for relatively good motion synchronization accuracy during double-cylinder erection.

[0003] Ultimately, the existing control method only ensures that the extension of the two cylinders is consistent. When the stiffness of the erecting arm is poor, it is also difficult to ensure that the internal forces or deformations of multiple erecting arms are consistent from left to right. When erecting various projectiles of different specifications, the projectile's center of gravity is unevenly loaded. If the same erection control parameters are still used, a radial deviation of the projectile's own center of gravity will occur during the erection process. At the same time, there will also be a slight deviation in the mounting hinge point between the cylinder and the erecting arm. Therefore, simply ensuring that the extension of the two hydraulic cylinders is consistent is not enough to ensure the left-right force balance of the erecting arm. It is impossible to completely eliminate the internal forces or deformations on the erecting arm and to guarantee the safety of the projectile during erection.

[0004] Meanwhile, in the existing launch commissioning phase, there is no monitoring and real-time feedback on the deformation of the erecting arm. For types such as 4-cylinder, 6-cylinder, and 8-cylinder erecting arms, the control and feedback logic is complex, resulting in poor projectile installation accuracy and a long commissioning time, which is also not conducive to ensuring reliability during use. Summary of the Invention

[0005] To address the shortcomings of existing technologies, this invention provides a method for synchronous erection control of multiple hydraulic cylinders. This method solves the problems that when using multiple cylinders such as 4-cylinder, 6-cylinder, or 8-cylinder erection systems to erect rockets, the control and feedback logic of the multi-cylinder structure is complex, resulting in poor rocket body installation accuracy, long debugging time, and compromised reliability during use.

[0006] To achieve the above objectives, the basic solution of the present invention is as follows: a method for controlling the synchronous erection of multiple hydraulic cylinders, comprising the following steps:

[0007] Preparation steps: Prepare the control system, install the erecting arm of the rocket body, several erecting cylinders that support the change of the erecting arm angle, and the hinges located between the erecting arm and the erecting cylinders. The erecting cylinders are symmetrically arranged along the vertical center plane of the erecting arm. The hinges correspond one-to-one with the erecting cylinders. The number of erecting cylinders is even. The control system is electrically connected to the erecting cylinders.

[0008] Strain gauge installation steps: Strain gauge A, which can fit with the erecting arm, is installed on the side of the hinge seat near the erecting arm; strain gauge B, which can fit with the hinge seat, is installed on the side of the hinge seat near the erecting arm; several erecting cylinders are controlled by the closed-loop control system.

[0009] Simulation calculation process: The control system synchronously starts several erecting cylinders to support and erect the erecting arm and rocket body. The control system obtains the values ​​ε1, ε2, ε3...ε of several strain gauges A installed on one side of the erecting cylinder of the erecting arm. N-1 ε N The control system obtains the values ​​β1, β2, β3...β of several strain gauges B installed on the erecting cylinder on the other side of the erecting boom. N-1 β N N is an even number; values ​​ε1 and ε2 are a symmetrically arranged set of erecting cylinders, with strain gauge A containing ε1 located inside the hinge and strain gauge A containing ε2 located outside the hinge; ε3 and ε4 are a symmetrically arranged set of erecting cylinders, with strain gauge A containing ε3 located inside the hinge and strain gauge A containing ε4 located outside the hinge; ... ε N-1 and ε N A set of symmetrically arranged lifting cylinders, ε N-1 The strain rosette A is located inside the hinge, ε N The strain gauge A is located outside the hinge seat; the control system performs discrimination calculations on the values ​​of strain gauge A and strain gauge B, and the difference range ε ​​between the values ​​of strain gauge A and strain gauge B in the same group of erecting cylinders within the control system is determined.

[0010] in:

[0011] ε 实测1 = ;ε 实测2 = ····

[0012] ε 实测N / 2 = ;

[0013] When ε 实测1 ε 实测2 ····ε 实测N / 2 When the measured absolute value is greater than the ε threshold, the control system automatically provides real-time feedback to control the lifting speed of the lifting cylinder until the cylinder is fully erected; when ε 实测1 ε 实测2 ····ε 实测N / 2 When the measured absolute value is less than the ε threshold, the control system automatically controls the erecting cylinder to continue erecting until it is in place.

[0014] The technical principle of this invention is as follows: In this control method, there is no need to extract and calculate data such as the shaft angle difference (corresponding to speed), the integral of the angle difference (corresponding to the extension length), or the derivative of the angle difference (corresponding to the rate of change of speed) between the cylinders. Instead, the stress and strain near the connection between the erecting arm and the erecting cylinder side is analyzed through a simulation calculation process using strain rosettes A and B. This stress change is directly fed back to the control system through strain rosettes A and B. The control system then processes the values ​​ε1, ε2, ε3...ε N-1 ε N and the values ​​β1, β2, β3····β N-1 β N Calculations were performed to obtain the measured value ε. 实测1 ε 实测2 ····ε 实测N / 2 The control system can compare with the ε threshold and then feed back to the control system. The control system can speed up or slow down the erection by controlling the erection cylinder on one side. By controlling the extension speed of the erection cylinder, the force and deformation on the left and right sides of the erection arm can be made to be close to the same. From the most fundamental level, the synchronization of the erection cylinder is solved, ensuring that the rocket body on the erection arm is not damaged.

[0015] During the strain gauge installation process, the connection between the hinge and the erecting arm is selected as a strain / stress monitoring point. Since stress is calculated by equivalent strain, only the strain value needs to be processed. First, the strain values ​​on both sides of the erecting arm are subtracted. Based on the Laplace and Fourier transform, the required input values ​​are obtained for the control system, along with the subtraction threshold set in the system. During the step extension of the erecting cylinder, real-time feedback is provided and it is determined whether the strain difference exceeds the threshold until the erection is completed.

[0016] Throughout the process, the ε threshold is a value set according to simulation calculations, which is ε. 实测1 ε 实测2 ····ε 实测N / 2 It provides a reference for value judgment; at the same time, it can monitor and control the erecting arm in real time. This monitoring and feedback control method can solve the problem of low synchronization of erecting accuracy caused by the torsional stiffness of the left and right sides of the erecting arm, the installation accuracy of the erecting cylinder, and the center of gravity offset caused by different projectiles. It can significantly improve the synchronization of erection and the adjustment rate of synchronization.

[0017] Furthermore, during the simulation calculation, when ε 实测1 ε 实测2 ····ε 实测N / 2 When the value is negative, the control system controls ε1, ε3...ε N-1 The lifting cylinder on one side slows down the lifting action; when ε 实测1 ε 实测2 ····ε 实测N / 2When the value is positive, the control system controls ε2, ε4...ε N The lifting cylinder on one side slows down the lifting action.

[0018] With the above settings, it is possible to determine the measured ε 实测1 ε 实测2 ····ε 实测N / 2 In numerical conditions, the control system can selectively control the adjusted erecting cylinders in real time, quickly controlling the strain / stress at the side of the erecting arm. The control speed is fast, ε 实测1 ε 实测2 ····ε 实测N / 2 The numerical feedback is also fast, which can effectively improve the synchronization of multi-cylinder erection.

[0019] Furthermore, when N is greater than or equal to 4, the control system obtains ε 实测1 and ε 实测N / 2 Data, when ε 实测1 and ε 实测N / 2 When the value is negative, the control system controls ε1, ε3...ε N-1 The lifting cylinder on one side slows down the lifting action; when ε 实测1 and ε 实测N / 2 When the value is positive, the control system controls ε2, ε4...ε N The lifting cylinder on one side slows down the lifting action.

[0020] With the above settings, compared with the traditional closed-loop PID control method, the number of iterations is reduced, the system feedback calculation time is reduced, and the reliability and simplicity of the control system are improved.

[0021] Furthermore, in the strain rose installation process, strain rose A is a triaxial 45° strain rose.

[0022] With the above settings, strain gauge A can measure parameters such as principal stress, shear stress, principal stress direction, and equivalent stress at the connection between the erecting arm and the hinge seat, which has a relatively complex structure. The measurement is highly accurate and efficient, making it more suitable for the field of rocket launch.

[0023] Furthermore, in the strain rose installation process, strain rose B is a triaxial 45° strain rose.

[0024] With the above settings, strain gauge B can measure parameters such as principal stress, shear stress, principal stress direction, and equivalent stress at the connection between the erecting arm and the hinge seat, which has a relatively complex structure. The measurement is highly accurate and efficient, making it more suitable for the field of rocket launch.

[0025] Furthermore, during the strain gauge installation process, strain gauge A is located on the upper side of the erecting arm.

[0026] With the above settings, the strain / stress changes between the erecting arm and the hinge can be accurately obtained, and the uniformity of strain / stress on the side of the erecting arm can be precisely controlled, reflecting the state of the erecting arm in the most realistic way. It is applicable regardless of whether it is an installation error or a centroid offset error of different spring types, and no readjustment is required. Attached Figure Description

[0027] Figure 1 This is a control flowchart of a method for synchronous erection control of multiple hydraulic cylinders in Embodiment 1 of the present invention.

[0028] Figure 2 This is a structural diagram of the erecting arm, rocket body, two erecting cylinders, and two hinge seats.

[0029] Figure 3 for Figure 2 Enlarged view of the position of the upper hinge seat of the central lifting cylinder from the main view direction.

[0030] Figure 4 This is a control flowchart of a method for synchronously raising multiple hydraulic cylinders in Embodiment 2 of the present invention.

[0031] In the above attached diagram: 1. Erection arm; 2. Erection cylinder; 3. Rocket body; 4. Hinge seat; 5. Strain gauge. Detailed Implementation

[0032] The technical solutions of the present invention will be further described below with reference to the accompanying drawings and embodiments.

[0033] Example 1

[0034] This embodiment is basically as follows: Figure 1 As shown in the figure, this invention proposes a method for controlling the synchronous erection of multiple hydraulic cylinders, which specifically includes the following steps:

[0035] Preparation steps: Prepare as follows Figure 2 The control system shown includes an erecting arm 1 that mounts the rocket body 3, several erecting cylinders 2 that support the erecting arm 1 to change its angle, and a hinge 4 located between the erecting arm 1 and the erecting cylinders 2. Several erecting cylinders 2 are symmetrically arranged along the vertical center plane of the erecting arm 1. The hinge 4 corresponds one-to-one with the erecting cylinder 2. There are two erecting cylinders 2. The erecting cylinders 2 are controlled by the closed-loop control system.

[0036] Strain rosette installation steps: Strain rosette A5, which can fit snugly against the erecting arm 1, is installed on the side of hinge 4 closest to the erecting arm 1. Strain rosette B, which can fit snugly against the hinge 4, is installed on the side of hinge 4 closest to the erecting arm 1. Both strain rosette A5 and strain rosette B are triaxial 45° strain rosettes. Figure 3 As shown, strain gauge A5 is located on the upper side of the erecting arm 1; several strain gauges A5 and several strain gauges B are electrically connected to the control system.

[0037] Simulation calculation process: such as Figure 1 As shown, the control system controls several erecting cylinders 2 to start synchronously, supporting and erecting the erecting arm 1 and the rocket body 3. The control system obtains the values ​​ε1 of several strain gauges A5 and β1 of several strain gauges B. The values ​​ε1 and ε2 are a symmetrically arranged set of erecting cylinders 2. The strain gauge A containing ε1 is located inside the hinge, and the strain gauge A containing ε2 is located outside the hinge. The control system performs discrimination calculations on the values ​​of strain gauges A5 and B. Within the same set of erecting cylinders 2, the difference range ε ​​is the threshold value.

[0038] in:

[0039] ε 实测1 = ;

[0040] Meanwhile, the ε threshold is a numerical value based on simulation calculations. This value requires the use of at least two different software programs, such as WORKBENCH and ABAQUS. When using software for simulation calculations, the "mesh quality" parameter in the software program must be selected at least at the "fine" level. Then, the simulation value A is obtained, and the simulation value A and the measured value ε are compared at that location based on multiple erections of the structure. 实测 Empirical fitting was performed to make the simulated value A closely approximate the measured value ε. 实测 The results are basically consistent, and the simulation value A is reliable;

[0041] When ε 实测1 When the measured absolute value is greater than the ε threshold, the control system automatically provides real-time feedback control to the erecting cylinder 2 until it is erected in place; when ε 实测1 When the value is negative, the control system controls the lifting cylinder 2 on the ε1 side to slow down the lifting action. At this time, the lifting cylinder 2 where ε1 is located is on the right side of the lifting arm 1; when ε 实测1 When the value is positive, the control system controls the lifting cylinder 2 on the ε2 side to slow down the lifting action. At this time, the lifting cylinder 2 where ε2 is located is on the left side of the lifting arm 1.

[0042] When ε 实测1 When the measured absolute value is less than the ε threshold, the control system automatically controls the erecting cylinder 2 to continue erecting until it is in place.

[0043] In this embodiment, the stress and strain near the connection between the lifting arm 1 and the lifting cylinder 2 are first analyzed through simulation calculations using strain gauges A5 and B. This stress variation is directly fed back to the control system via strain gauges A5 and B. The control system then calculates the values ​​ε1 and β1 to obtain the measured value ε. 实测1The control system can compare with the ε threshold and then feed back to the control system. The control system can speed up or slow down the erection by controlling the erection cylinder 2 on one side. By controlling the extension speed of the erection cylinder 2, the force and deformation on the left and right sides of the erection arm 1 can be made to be close to the same. From the most fundamental level, the synchronization of the erection cylinder 2 is solved, ensuring that the various projectiles on the erection arm 1 are not damaged.

[0044] Meanwhile, this control method eliminates the need for data extraction and calculation based on the shaft angle difference (corresponding to speed), integral of the angle difference (corresponding to extension length), or derivative of the angle difference (corresponding to the rate of change of speed) between cylinders, thus improving debugging efficiency and accuracy. When the launch device has limited volume space for the erecting arm 1, the erecting arm 1 cannot be made robust, and the stiffness of the left and right torsional trend cannot be guaranteed. In this embodiment, the connection between the hinge 4 and the erecting arm 1 is selected as the strain / stress monitoring point. Since stress is calculated by equivalent strain, only the strain value needs to be processed. First, the strain values ​​on both sides of the erecting arm 1 are subtracted. Based on the Laplace and Fourier transforms, the required input values ​​for the control system are obtained, along with the subtraction threshold set in the system. During the step extension process of the erecting cylinder, real-time feedback and judgment are made on whether the strain difference exceeds the threshold until the erection is completed. The stress-strain closed-loop feedback control method can directly and fundamentally reduce the requirements for the left and right torsional stiffness of the erecting arm 1, or even eliminate the requirements altogether.

[0045] Meanwhile, traditional control methods require debugging and parameter adjustment of the control system for specific projectile types before use. The purpose is to compensate for the offset of the center of gravity of the rocket body 3 and the installation error between the upper and lower hinge points on the left and right sides of the erecting cylinder 2 and the erecting arm 1 under that specific state. The installation and adjustment of the rocket body 3 and the erecting cylinder 2 are time-consuming and labor-intensive. The problems solved by debugging are only for the same type of rocket body 3 center of gravity offset or erecting cylinder 2 installation misalignment. When a different rocket body 3 is used and the center of gravity offset of the rocket body 3 is different, it is necessary to readjust. However, in this embodiment, the deformation and stress of the left and right sides of the final erecting arm 1 are directly monitored, which most realistically reflects the state of the erecting arm 1. Regardless of whether it is an installation error, it can also be directly adjusted for the center of gravity offset error of different projectile types. It is applicable when erecting different rocket bodies 3 and does not require readjustment.

[0046] Example 2

[0047] The differences between Example 2 and Example 1 are basically as follows: Figure 4 As shown, when N equals 8, the control system obtains ε 实测1 and ε 实测4 Data, when ε 实测1 When the value is negative, the control system controls the lifting cylinder 2 on the side of ε1 to slow down the lifting action. The lifting cylinder 2 where ε1 is located is on the right side of the lifting arm 1; when ε实测4 When the value is negative, the control system controls the lifting cylinder 2 on the ε7 side to slow down the lifting action. The lifting cylinder 2 containing ε7 is located on the right side of the lifting arm 1; when ε 实测1 When the value is positive, the control system controls the erecting cylinder 2 on the ε2 side to slow down the erecting action; the erecting cylinder 2 containing ε2 is located on the left side of the erecting arm 1. 实测4 When the value is positive, the control system controls the lifting cylinder 2 on one side of ε8 to slow down the lifting action. The lifting cylinder 2 where ε8 is located is on the left side of the lifting arm 1.

[0048] In a traditional control scheme, the synchronization monitoring of the lifting cylinders 2 requires monitoring and iteration in pairs. For example, if 8 lifting cylinders 2 are lifting synchronously, each step requires 28 (7+6+5+4+3+2+1) iterations. This not only prevents the lifting speed of the lifting cylinders 2 from being increased, but also places higher demands on the reliability of the entire control system. However, with this embodiment, if 8 cylinders are lifting, it is only necessary to monitor the stress and strain at the two symmetrically arranged lifting cylinders 2, hinge 4, and lifting arm 1 on the outermost and innermost sides. That is, each step only requires 2 iterations, which greatly improves the simplicity and reliability of the control logic of the control system.

[0049] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for controlling the synchronous erection of multiple hydraulic cylinders, characterized in that, Includes the following steps: Preparation steps: Prepare the control system, install the erecting arm of the rocket body, several erecting cylinders that support the change of the erecting arm angle, and the hinges located between the erecting arm and the erecting cylinders. The erecting cylinders are symmetrically arranged along the vertical center plane of the erecting arm. The hinges correspond one-to-one with the erecting cylinders. The number of erecting cylinders is even. The erecting cylinders are controlled by the closed loop control system. Strain gauge installation steps: Install strain gauge A, which can fit against the erecting arm, on the side of the hinge seat near the erecting arm. Install strain gauge B, which can fit against the hinge seat, on the side of the hinge seat near the erecting arm. Several strain gauges A and several strain gauges B are electrically connected to the control system. Simulation calculation process: The control system synchronously starts several erecting cylinders to support and erect the erecting arm and rocket body. The control system obtains the values ​​ε1, ε2, ε3...ε of several strain gauges A installed on one side of the erecting cylinder of the erecting arm. N-1 ε N The control system obtains the values ​​β1, β2, β3...β of several strain gauges B installed on the erecting cylinder on the other side of the erecting boom. N-1 β N N is an even number; values ​​ε1 and ε2 are a symmetrically arranged set of erecting cylinders, with strain gauge A containing ε1 located inside the hinge and strain gauge A containing ε2 located outside the hinge; ε3 and ε4 are a symmetrically arranged set of erecting cylinders, with strain gauge A containing ε3 located inside the hinge and strain gauge A containing ε4 located outside the hinge; ... ε N-1 and ε N A set of symmetrically arranged lifting cylinders, ε N-1 The strain rosette A is located inside the hinge, ε N The strain gauge A is located outside the hinge seat; the control system performs discrimination calculations on the values ​​of strain gauge A and strain gauge B, and the difference range ε ​​between the values ​​of strain gauge A and strain gauge B in the same group of erecting cylinders within the control system is determined. in: e 实测1 = ; e 实测2 = ···· e 实测N / 2 = ; When ε 实测1 ε 实测2 ····ε 实测N / 2 When the measured absolute value is greater than the ε threshold, the control system automatically provides real-time feedback to control the lifting speed of the lifting cylinder until the cylinder is fully erected; when ε 实测1 ε 实测2 ····ε 实测N / 2 When the measured absolute value is less than the ε threshold, the control system automatically controls the erecting cylinder to continue erecting until it is in place.

2. The method for synchronous erection control of multiple hydraulic cylinders as described in claim 1, characterized in that, During the simulation calculation process, when ε 实测1 ε 实测2 ····ε 实测N / 2 When the value is negative, the control system controls ε1, ε3...ε N-1 The lifting cylinder on one side slows down the lifting action; when ε 实测1 ε 实测2 ····ε 实测N / 2 When the value is positive, the control system controls ε2, ε4...ε N The lifting cylinder on one side slows down the lifting action.

3. The method for synchronous erection control of multiple hydraulic cylinders as described in claim 2, characterized in that, When N is greater than or equal to 4, the control system obtains ε 实测1 and ε 实测N / 2 Data, when ε 实测1 and ε 实测N / 2 When the value is negative, the control system controls ε1, ε3...ε N-1 The lifting cylinder on one side slows down the lifting action; when ε 实测1 and ε 实测N / 2 When the value is positive, the control system controls ε2, ε4...ε N The lifting cylinder on one side slows down the lifting action.

4. The method for synchronous erection control of multiple hydraulic cylinders as described in claim 2, characterized in that, In the strain rose installation step, strain rose A is a triaxial 45° strain rose.

5. The method for synchronous erection control of multiple hydraulic cylinders as described in claim 4, characterized in that, In the strain rose installation step, strain rose B is a triaxial 45° strain rose.

6. The method for synchronous erection control of multiple hydraulic cylinders as described in claim 5, characterized in that, In the strain gauge installation step, strain gauge A is located on the upper side of the erecting arm.

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