A method for eliminating redundant force conflicts in statically indeterminate systems

Abstract

A method for eliminating redundant force disputes in an over-determined system relates to the field of automatic control technology. It solves the problems of poor control system accuracy, high noise, and low static output caused by redundant force disputes in existing over-determined systems. The method includes: constructing an over-determined system, wherein the over-determined system includes: a conventional rigid body position loop and a redundant force control loop; obtaining a rigid body posture decomposition factor according to the over-determined system; calculating a rigid body posture synthesis factor according to the rigid body posture decomposition factor; calculating a deformation posture decomposition factor according to the rigid body posture synthesis factor; generating a position correction control signal according to the redundant force controller and the deformation posture decomposition factor; generating a position loop control signal according to the posture controller and the rigid body posture decomposition factor; superimposing the position correction control signal and the position loop control signal as the input signal to excite the system, thereby completing the elimination of redundant force disputes. It is applied to the control of over-determined systems in ground test equipment in the fields of transportation, aerospace, civil engineering, etc.

Description

Technical Field

[0001] The present invention relates to the field of automatic control technology, and in particular to a method for eliminating redundant force disputes in a hyperstatic system. Background Art

[0002] Electromechanical systems are widely used in the control loops of typical equipment, particularly complex test equipment with heavy loads, demanding test specifications, and large load masses. Because these devices require high-precision control and multi-position motion, a single servo actuator often cannot meet the precise control requirements for multiple positions and complex paths. Therefore, to ensure the system can achieve multiple different positions, multiple servo actuators are typically deployed at each position, resulting in a statically indeterminate structure for the entire test equipment.

[0003] In this structure, the number of driven actuators far exceeds the actual number of required poses, causing the system to exhibit overconstrained characteristics. This excess number of actuators is actually the difference between the number of actuators and the number of achieved poses. The core challenge of this design is that although the number of actuators in the system exceeds the actual requirement, if the motion accuracy of these actuators is inconsistent, it may cause undesirable deformation of other poses. In other words, due to the difference in actuator accuracy, the actuators within the system may affect each other, resulting in unstable dynamic performance of the entire system.

[0004] In practical applications, unwanted deformations are often constrained by mechanical components such as hinges and springs, limiting unnecessary motion. However, this constraint mechanism cannot completely eliminate the unintended deformation caused by inconsistent motion accuracy between actuators. In this case, the deformation tendency often leads to mutual resistance between the actuators, resulting in so-called "excess force" or "internal force conflict." The generation of these excess forces directly affects the control accuracy of the system and may cause the static output force of the actuator to decrease, thereby affecting the accuracy and reliability of the entire control system.

[0005] Currently, existing technologies mainly reduce the impact of excess force in the system by improving the control accuracy of each actuator, improving the assembly process, and increasing processing accuracy. However, although these methods can improve system performance to a certain extent, they also have some limitations. For example, simply improving the accuracy of the actuator to solve the problem has certain limits, because the improvement of the accuracy of each actuator is constrained by cost, technology, and manufacturing processes. In addition, it is often difficult to maintain complete consistency in the dynamic characteristics of the actuators. Especially under complex load conditions, the response speed, inertia characteristics, and nonlinear characteristics of each actuator may vary, thus affecting the overall coordination and stability of the system.

[0006] At the same time, machining and assembly errors are also a significant concern. These errors inevitably occur during the production and assembly process and directly lead to inconsistencies between actuators. Even with high-precision manufacturing techniques, it is difficult to completely eliminate these errors. Due to these errors, the actuators may move asynchronously, generating unbalanced forces or torques in the system, further exacerbating the generation of excess forces. Summary of the Invention

[0007] The present invention addresses the problems of poor control system accuracy, high noise, and low static output caused by redundant force disputes in existing statically indeterminate systems. A method for eliminating redundant force disputes in statically indeterminate systems is proposed. The method comprises:

[0008] Constructing a hyperstatic system, the hyperstatic system comprising: a conventional rigid body position loop and a redundant force control loop;

[0009] Obtain the rigid body posture decomposition factor based on the hyperstatic system;

[0010] Calculate the rigid body posture synthesis factor according to the rigid body posture decomposition factor;

[0011] Calculate the deformation pose decomposition factor based on the rigid body pose synthesis factor;

[0012] Generate a position correction control signal based on the redundant force controller and the deformation posture decomposition factor;

[0013] Generate control signals for the position loop based on the posture controller and the rigid body posture decomposition factors;

[0014] The position correction control signal and the position loop control signal are superimposed as the input signal to excite the system and eliminate the redundant force disputes.

[0015] Furthermore, a preferred embodiment is proposed, wherein the hyperstatic system is:

[0016] KM T f c +KT T f d =Kf

[0017] Among them, M is the pose synthesis factor, f c To achieve rigid pose s c Output of the actuator, f d is the deformation pose s d The output of the actuator, K is the redundant force synthesis factor, T represents the mapping relationship from the actuator displacement to the deformed posture, and f is a vector.

[0018] Furthermore, a preferred embodiment is proposed, in which the dimension of the posture synthesis factor is n×m, wherein n represents the number of actuators and m represents the number of rigid body postures achieved.

[0019] Furthermore, a preferred method is proposed, wherein the rigid body posture synthesis factor is calculated based on the rigid body posture decomposition factor, including:

[0020] M=(N T N) -1 N T

[0021] Among them, N T is the transpose of the pose decomposition factor.

[0022] Furthermore, a preferred method is proposed, wherein the deformation posture decomposition factor is calculated based on the rigid body posture synthesis factor, including:

[0023] MJ=0

[0024] Among them, J is the posture decomposition factor of the system to achieve the deformed posture.

[0025] Furthermore, a preferred embodiment is proposed, wherein the deformation posture decomposition factor generates a position correction control signal, including:

[0026] K=J T .

[0027] Furthermore, a preferred embodiment is proposed, wherein the method further comprises: when the position correction control signal and the position loop control signal are superimposed as the input signal excitation system, the redundant force control loop force input signal is set to 0.

[0028] Based on the same inventive concept, the present invention also proposes a computer device, including a memory and a processor, wherein a computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes a method for eliminating redundant force disputes in an over-determined system according to any one of the above items.

[0029] Based on the same inventive concept, the present invention also proposes a computer-readable storage medium, which stores a computer program. When the computer program is executed by a processor, the steps of the method for eliminating redundant force disputes in an over-determined system as described in any one of the above are executed.

[0030] The present invention is beneficial in that:

[0031] The method proposed in the present invention accurately controls the posture of the rigid body by decomposing the posture factor and synthesis factor of the rigid body, ensuring that every force and constraint in the system can be correctly distributed under the action of the controller, thereby reducing the redundant force disputes in the system. By using the superposition of the position correction control signal and the position loop control signal, the oscillation and noise caused by the redundant force can be effectively eliminated, making the response of the system more stable and avoiding the strong oscillation phenomenon caused by redundant forces in traditional statically indeterminate systems. By accurately calculating the posture decomposition factor and generating the control signal according to the deformed posture decomposition factor, the controller's regulation of the redundant force can be optimized, which can improve the static output of the system and make the force output of the statically indeterminate system more effective.

[0032] The method proposed in the present invention can effectively control the position and posture of the rigid body by rationally decomposing and synthesizing the posture factors, reduce the errors caused by excess forces, and thus improve the accuracy of the control system. The excess force control loop and position correction control signal can effectively eliminate the system instability caused by the struggle of excess forces, reduce oscillations and noise, and ensure that the system runs more smoothly. Through precise posture control and correction, the distribution of force is more reasonable, ensuring that the hyperstatic system can provide sufficient static output, thereby improving the execution ability and efficiency of the system. Due to the precise control of the posture factors, combined with the superposition of the correction control signals, the system response is smoother, reducing the impact of dynamic noise on the stability of the system.

[0033] The present invention is applied to the control of hyperstatic systems in ground test equipment in the fields of transportation, aerospace, civil engineering, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 This is a flow chart of a method for eliminating redundant force disputes in an indeterminate system according to the first embodiment;

[0035] Figure 2 Schematic diagram of a hyperstatic system according to Embodiment 10;

[0036] Figure 3 Schematic diagram of deformation caused by excess force according to the tenth embodiment;

[0037] Figure 4 This is a layout diagram of a dual-channel structure of a certain type of truck-mounted crane arm according to the tenth embodiment;

[0038] Figure 5 This is a structural layout diagram of a certain type of automobile testing center according to the tenth embodiment;

[0039] Figure 6 This is a layout diagram of a certain type of statically indeterminate structure described in Embodiment 10;

[0040] Figure 7 This is a diagram showing the effect of eliminating excess force as described in the tenth embodiment. DETAILED DESCRIPTION

[0041] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in combination with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments.

[0042] Implementation method 1, see Figure 1 This embodiment describes a method for eliminating redundant force conflicts in a hyperstatic system, the method comprising:

[0043] Constructing a hyperstatic system, the hyperstatic system comprising: a conventional rigid body position loop and a redundant force control loop;

[0044] Obtain the rigid body posture decomposition factor based on the hyperstatic system;

[0045] Calculate the rigid body posture synthesis factor according to the rigid body posture decomposition factor;

[0046] Calculate the deformation pose decomposition factor based on the rigid body pose synthesis factor;

[0047] Generate a position correction control signal based on the redundant force controller and the deformation posture decomposition factor;

[0048] Generate control signals for the position loop based on the posture controller and the rigid body posture decomposition factors;

[0049] The position correction control signal and the position loop control signal are superimposed as the input signal to excite the system and eliminate the redundant force disputes.

[0050] The method proposed in this embodiment accurately controls the posture of the rigid body by decomposing the posture factor and synthesis factor of the rigid body, ensuring that every force and constraint in the system can be correctly distributed under the action of the controller, thereby reducing the redundant force disputes in the system. By using the superposition of the position correction control signal and the position loop control signal, the oscillation and noise caused by the redundant force can be effectively eliminated, making the response of the system more stable, and avoiding the strong oscillation phenomenon caused by the redundant force in the traditional hyperstatic system. By accurately calculating the posture decomposition factor and generating the control signal according to the deformed posture decomposition factor, the controller's regulation of the redundant force can be optimized, which can improve the static output of the system and make the force output of the hyperstatic system more effective.

[0051] The method proposed in this embodiment can effectively control the position and posture of the rigid body by rationally decomposing and synthesizing the posture factors, reduce the errors caused by excess forces, and thus improve the accuracy of the control system. The excess force control loop and position correction control signal can effectively eliminate the system instability caused by the struggle of excess forces, reduce oscillations and noise, and ensure that the system runs more smoothly. Through precise posture control and correction, the distribution of force is more reasonable, ensuring that the hyperstatic system can provide sufficient static output, thereby improving the execution capability and efficiency of the system. Due to the precise control of the posture factors, combined with the superposition of the correction control signals, the system response is smoother, reducing the impact of dynamic noise on the stability of the system.

[0052] Implementation 2: This implementation further limits the method for eliminating redundant force disputes in a statically indeterminate system described in Implementation 1. The statically indeterminate system is:

[0053] KM T f c +KT T f d =Kf

[0054] Among them, M is the pose synthesis factor, f c To achieve rigid pose s c Output of the actuator, f d is the deformation pose s d The output of the actuator, K is the redundant force synthesis factor, T represents the mapping relationship from the actuator displacement to the deformed posture, and f is a vector.

[0055] Implementation method three. This implementation method further limits the method for eliminating redundant force disputes in an over-determined system described in implementation method one. The dimension of the posture synthesis factor is n×m, where n represents the number of actuators and m represents the number of rigid body postures achieved.

[0056] Implementation 4: This implementation further limits the method for eliminating redundant force disputes in an indeterminate system described in Implementation 2. The calculation of the rigid body posture synthesis factor based on the rigid body posture decomposition factor includes:

[0057] M=(N T N) -1 N T

[0058] Among them, N T is the transpose of the pose decomposition factor.

[0059] Implementation 5: This implementation further limits the method for eliminating redundant force disputes in an indeterminate system described in Implementation 2. The method of calculating the deformation posture decomposition factor based on the rigid body posture synthesis factor includes:

[0060] MJ=0

[0061] Among them, J is the posture decomposition factor of the system to achieve the deformed posture.

[0062] Implementation 6: This implementation further limits the method for eliminating redundant force disputes in an indeterminate system described in Implementation 5. The deformation posture decomposition factor generates a position correction control signal, including:

[0063] K=J T .

[0064] Implementation method seven. This implementation method is a further limitation of the method for eliminating redundant force disputes in an over-determined system described in any one of implementation methods one to six. The method also includes: when the position correction control signal and the position loop control signal are superimposed as input signals to excite the system, the redundant force control loop force input signal is set to 0.

[0065] Implementation 8. A computer device described in this implementation includes a memory and a processor, wherein a computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes a method for eliminating redundant force disputes in an over-determined system according to any one of Implementation 1 to Implementation 7.

[0066] Implementation method nine: A computer-readable storage medium described in this implementation method stores a computer program, and when the computer program is executed by a processor, the steps of a method for eliminating redundant force disputes in a hyperstatic system as described in any one of implementation methods one to seven are executed.

[0067] Implementation Method 10: See Figures 2 to 7 This embodiment provides a specific example of the method for eliminating redundant force conflicts in an indeterminate system described in the first embodiment, and is also used to explain the second to seventh embodiments. Specifically:

[0068] like Figure 2 As shown in the figure, suppose there are n actuators in the hyperstatic system, and the displacement and output of each actuator are represented by y i 、f i (i=1,…,n) represents the vectors y and f. To achieve the rigid body pose s c =[s c,1 s c,2 Ks c,m ] T The number is m, then the deformation pose (such as Figure 3 (shown)s d =[s d,1 s d,2Ks d,n-m ] T The number is nm, then we have

[0069]

[0070] Among them, N and J are the posture decomposition factors of the system to realize rigid posture and deformed posture, and the dimensions are n×m and n×(nm) respectively.

[0071] Corresponding to N is the pose synthesis factor M, the dimension is m×n, and there are s c =My,MN=I m , which can be obtained by taking the pseudo-inverse of N

[0072] M=(N T N) -1 N T (2)

[0073] Multiplying both sides of equation (1) by M, we have

[0074] MJ=0 (3)

[0075] J consists of M null space basis vectors with dimension n×(nm), which can be obtained by finding the M null space rational basis.

[0076] Assume that the rigid pose s is achieved c The actuator output is expressed as f c =[f c,1 f c,2 Kf c,m ] T , the corresponding deformation pose s d The actuator output is expressed as f d =[f d,1 f d,2 Kf d,n-m ] T , then

[0077]

[0078] Let T represent the mapping relationship from actuator displacement to deformation posture, that is, s d =Ty, the dimension is (nm)×n, then equation (4) becomes

[0079] M T f c +T T f d =f (5)

[0080] Let K be the redundant force synthesis factor, which represents the mapping relationship between the actuator output and the deformation posture force, that is, f d =Kf, the dimension is (nm)×n, since fc = 0 when T T f d =f, so KT T =I n-m From equation (4), we have

[0081] KM T f c +KT T f d =Kf (6)

[0082] Therefore, equation (6) becomes KM T = 0. Considering equation (3), we have

[0083] K=J T (7)

[0084] It can be seen that in the deformed posture, the force synthesis factor K and the posture decomposition factor J are also the same as the rigid body posture, and are in a transposed relationship with each other.

[0085] The process of eliminating excess force is as follows:

[0086] 1) First, the rigid body posture decomposition factor N is given according to the specific structure of the system;

[0087] 2) Calculate the rigid body posture synthesis factor M = (N T N) -1 N T

[0088] 3) Calculate the deformation posture decomposition factor J, satisfying MJ = 0

[0089] 4) Calculate the excess force synthesis factor K = J T

[0090] Control block diagram Figure 1 As shown. The entire system control consists of two control loops: one is the conventional rigid body position loop, and the other is the redundant force control loop. In the position loop, the displacement values ​​y1, y2, ..., y collected by the displacement sensor are n , converted from the rigid body posture synthesis factor M to the posture signal s c,1 ,s c ,2,…,s c,m , and is superimposed with the posture command to form a control deviation signal. Then, the control signal of the position loop is generated through the posture controller and the rigid body posture decomposition factor N. In the redundant force control loop, the output value f1, f2, ..., f of the actuator is collected by the force sensor. n , converted from the excess force synthesis factor K to the excess force signal f d,1 ,f d,2 ,…,f d,n-m, which is superimposed on the force command signal to form a force deviation signal. This signal is then passed through the excess force controller and the deformation posture decomposition factor J to generate a position correction control signal. This position correction control signal is superimposed on the position loop control signal as the input signal to excite the system. To eliminate excess force contention in the system, the excess force control loop force input signal command is set to 0.

[0091] In order to verify the effect of this method, actual simulations were also carried out. Figure 4 As shown, actuators 1 and 2 simultaneously activate the boom of the truck crane. Before activation, the boom is locked by the truck crane system, so that the boom can only rotate in one position. Therefore, n = 2, m = 1, and the above redundant force control process is:

[0092]

[0093] In the figure, a=2, b=4.

[0094] Figure 5 In the example, actuators 1 through 8 simultaneously excite the wheelset system. Before excitation, the control system is constrained to only move along the X and Y axes and yaw along the Z axis. Therefore, n = 8 and m = 3. The redundant force control process described above is:

[0095]

[0096] Figure 6 In the example, actuators 1 to 8 simultaneously stimulate the earthquake simulation platform to simulate the six rigid body positions in space. Therefore, n = 8, m = 6, and the redundant force control process is as follows:

[0097]

[0098]

[0099] Figure 7 The effect diagram after applying the redundant force elimination method to the system shows that the redundant force is obviously eliminated by adopting this method.

[0100] Although the preferred embodiments of the present disclosure have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concepts. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present disclosure.

[0101] Obviously, those skilled in the art may make various changes and modifications to the present disclosure without departing from the spirit and scope of the present disclosure. Thus, if these modifications and variations of the present disclosure fall within the scope of the claims of the present disclosure and their equivalents, the present disclosure is intended to include these modifications and variations.

[0102] Those skilled in the art will appreciate that embodiments of the present disclosure may be provided as methods, systems, or computer program products. Thus, the present disclosure may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware. Furthermore, the present disclosure may take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0103] The present disclosure is described with reference to flowcharts and / or block diagrams of methods, devices (systems) and computer program products according to embodiments of the present disclosure. It should be understood that each process and / or block in the flowchart and / or block diagram and the combination of processes and / or blocks in the flowchart and / or block diagram can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 a process or multiple processes and / or boxes Figure 1 These computer program instructions can also be stored in a computer-readable memory that can guide a computer or other programmable data processing device to work in a specific way, so that the instructions stored in the computer-readable memory produce a product including the instruction device, which implements the function specified in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0104] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0105] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present disclosure and are not intended to limit its scope of protection. Although the present disclosure has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field should understand that after reading the present disclosure, those skilled in the art can still make various changes, modifications or equivalent substitutions to the specific implementation methods of the invention, but these changes, modifications or equivalent substitutions are all within the scope of protection of the disclosed claims.

Claims

1. A method for eliminating redundant force disputes in an indeterminate system, characterized in that: The method comprises: Constructing a hyperstatic system, the hyperstatic system comprising: a conventional rigid body position loop and a redundant force control loop; Obtain the rigid body posture decomposition factor based on the hyperstatic system; Calculate the rigid body posture synthesis factor according to the rigid body posture decomposition factor; Calculate the deformation pose decomposition factor based on the rigid body pose synthesis factor; Generate a position correction control signal based on the redundant force controller and the deformation posture decomposition factor; Generate control signals for the position loop based on the posture controller and the rigid body posture decomposition factors; The position correction control signal and the position loop control signal are superimposed as the input signal to excite the system and eliminate the redundant force disputes; The hyperstatic system is: in, M is the pose synthesis factor, To achieve rigid posture The output of the actuator, Deformed pose The output of the actuator, K It is the excess force synthesis factor, T Represents the mapping relationship from actuator displacement to deformed posture, f is a vector; The dimension of the pose synthesis factor is n × m ,in, n Indicates the number of actuators, m Indicates the number of rigid body poses achieved; Calculating the rigid body posture synthesis factor according to the rigid body posture decomposition factor includes: in, is the transpose of the pose decomposition factor; The calculation of the deformation posture decomposition factor according to the rigid body posture synthesis factor includes: in, J The pose decomposition factor that realizes the deformed pose for the system; The deformation posture decomposition factor generates a position correction control signal, including: ； The method further includes: when the position correction control signal and the position loop control signal are superimposed as the input signal to excite the system, setting the redundant force control loop force input signal to 0.

2. A computer device, characterized in that: The method comprises a memory and a processor, wherein a computer program is stored in the memory. When the processor runs the computer program stored in the memory, the processor executes the method for eliminating redundant force disputes in a hyperstatic system according to claim 1.

3. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, which, when executed by a processor, executes the steps of the method for eliminating redundant force disputes in a hyperstatic system as claimed in claim 1.

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