High-precision modal testing method and related equipment
By introducing stress field quantification constraints during the spring design stage of modal testing instruments, the spring design variables are optimized, solving the problem of local plastic deformation caused by stress concentration in modal testing instruments and improving the accuracy and stability of modal testing.
Patent Information
- Application Number
- CN202511488519.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-17
- Publication Date
- 2026-02-10
AI Technical Summary
Springs in modal testing instruments are prone to stress concentration during the process of being subjected to force, which leads to local plastic deformation, affecting the elastic performance and stability of the spring, and thus affecting the accuracy and reliability of modal test results.
In the spring design stage of modal testing instruments, stress field quantification constraints are introduced. By calculating the characteristic parameters of the stress field and evaluating whether they meet the preset constraints, the spring design variables are optimized to reduce stress concentration and improve design accuracy and reliability.
Significantly reduces the spring design iteration cycle, improves the accuracy and stability of modal testing, and meets the design requirements of high-reliability springs.
Smart Images
Figure CN121502931A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of structural dynamics testing technology, and in particular to a high-precision modal testing method and related equipment. Background Technology
[0002] Currently, modal testing is the primary means of obtaining dynamic parameters such as the natural frequencies, damping, and mode shapes of a structure, and it is widely used in aerospace, automotive, and machinery manufacturing industries.
[0003] In related technologies, during actual testing, the springs in modal testing instruments, as support and excitation elements, are often affected by stress concentration. That is, when the spring is subjected to force, stress concentration is easily generated at the ends and support points, leading to local plastic deformation, which affects the elastic performance and stability of the spring, thereby affecting the accuracy and reliability of the modal test results.
[0004] In summary, the technical problems existing in the relevant technologies need to be improved. Summary of the Invention
[0005] This application provides a high-precision modal testing method and related equipment, which can effectively improve the spring design accuracy and reliability of modal testing instruments, significantly reduce the spring design iteration cycle, improve the accuracy and stability of modal testing, and effectively meet the design requirements of high-reliability springs.
[0006] On the one hand, embodiments of this application provide a high-precision modal testing method, the method comprising the following steps: Obtain spring design parameters and initialize spring design variables; Based on the spring design parameters and the spring design variables, the stress field characteristic parameters are calculated. The stress field characteristic parameters are evaluated based on the preset stress field constraints. If the stress field characteristic parameters satisfy the stress field constraint conditions, the spring design variables are output as the spring design result. A spring is fabricated based on the spring design results, and modal testing is performed using the spring.
[0007] Optionally, obtaining spring design parameters and initializing spring design variables includes: In response to the input spring design requirements, obtain the spring design parameters; Based on the spring design parameters, the spring design variables are initialized and calculated. The spring design parameters include the mass of the test piece in the modal test, the target modal frequency, the allowable modal frequency offset, the target stiffness, the working stroke, the rated load, the constraints of the installation space, the shear modulus, the fatigue limit, and the stress field characteristic parameter constraint threshold; the spring design variables include the effective number of coils, the mean diameter, the pitch, the radius of curvature, and the end grinding length.
[0008] Optionally, the calculation of stress field characteristic parameters based on the spring design parameters and the spring design variables includes: Calculate the Wahl correction factor based on the spring winding ratio; Based on the aforementioned Wahl correction factor, the maximum shear stress is determined, thereby calculating the maximum value of the local stress gradient; Based on the three-dimensional stress attenuation model, combined with the maximum shear stress and fatigue limit, the volume ratio of the high-stress zone is calculated. The risk of fretting is calculated based on the contact pressure and slip amplitude. The target equivalent stiffness is calculated based on the offset between the target modal frequency and the allowable modal frequency. The equivalent linearized stiffness is calculated based on the spring stiffness. The support stiffness matching coefficient is calculated based on the target equivalent stiffness and the equivalent linearized stiffness. The calculation results of the maximum value of the local stress gradient, the volume ratio of the high-stress zone, the fretting risk, and the support stiffness matching coefficient are obtained and used as the stress field characteristic parameters.
[0009] Optionally, the method further includes: If the stress field characteristic parameters do not meet the stress field constraint conditions, the spring design variables are corrected based on the preset correction rules, and the stress field characteristic parameters are recalculated. The recalculated stress field characteristic parameters are evaluated based on the preset stress field constraints.
[0010] Optionally, the step of correcting the spring design variables based on preset correction rules includes: The stress field characteristic parameters include the maximum local stress gradient, the volume ratio of the high-stress zone, the risk of fretting, and the support stiffness matching coefficient. If the maximum value of the local stress gradient is greater than the upper limit threshold of the local stress gradient, increase the radius of curvature and / or increase the end grinding length; If the volume ratio of the high-stress zone is greater than the upper limit threshold of the high-stress zone volume ratio, the effective number of rings is increased; If the micro-motion risk exceeds the upper limit threshold of the micro-motion risk, increase the pitch; If the support stiffness matching coefficient is greater than the upper limit threshold of the support stiffness matching coefficient, increase the mean diameter and / or decrease the spring wire diameter; If the support stiffness matching coefficient is less than the lower limit threshold of the support stiffness matching coefficient, reduce the mean diameter and / or increase the spring wire diameter.
[0011] Optionally, after outputting the spring design variables as the spring design result, the method further includes: Based on the spring design results, Monte Carlo load tests and fatigue life verification were conducted to obtain the reliability verification results of the spring design results.
[0012] On the other hand, embodiments of this application provide a high-precision modal testing device, the device comprising: The parameter acquisition module is used to acquire spring design parameters and initialize and generate spring design variables; The parameter calculation module is used to calculate the stress field characteristic parameters based on the spring design parameters and the spring design variables. The parameter evaluation module is used to evaluate the characteristic parameters of the stress field based on preset stress field constraints. The parameter output module is used to output the spring design variables as the spring design result when the stress field characteristic parameters satisfy the stress field constraint conditions. The modal testing module is used to prepare the spring based on the spring design results and to perform modal testing on the spring.
[0013] On the other hand, embodiments of this application provide an electronic device, which includes a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the above-described method.
[0014] On the other hand, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.
[0015] On the other hand, embodiments of this application provide a computer program product, including a computer program that, when executed by a processor, implements the above-described method.
[0016] This application embodiment introduces stress field quantification constraints during the forward design stage of the modal testing instrument spring to evaluate the characteristic parameters of the modal testing instrument spring. This can effectively improve the design accuracy and reliability of the modal testing instrument spring, significantly reduce the spring design iteration cycle, improve the accuracy and stability of modal testing, and effectively meet the design requirements of high-reliability springs. Attached Figure Description
[0017] Figure 1 This is a schematic diagram of the implementation environment of a high-precision modal testing method provided in an embodiment of this application; Figure 2 This is a flowchart illustrating a high-precision modal testing method provided in an embodiment of this application; Figure 3 This is a schematic diagram of a high-precision modal testing structure provided in an embodiment of this application; Figure 4 This is a schematic diagram of a high-precision modal testing correction process provided in an embodiment of this application; Figure 5 This is a schematic diagram of the structure of a high-precision modal testing device provided in an embodiment of this application; Figure 6 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of this application. Detailed Implementation
[0018] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of this application and are not intended to limit it. In the following description, when referring to the accompanying drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with those of this application; they are merely examples of apparatuses and methods consistent with some aspects of the embodiments of this application as detailed in the appended claims.
[0019] It is understood that the terms “first,” “second,” etc., used in this application may be used herein to describe various concepts, but unless otherwise stated, these concepts are not limited by these terms. These terms are only used to distinguish one concept from another. For example, without departing from the scope of the embodiments of this application, first information may also be referred to as second information, and similarly, second information may also be referred to as first information. Depending on the context, the words “if,” “when,” or “in response to a determination” as used herein may be interpreted as “when…” or “when…” or “in response to a determination.”
[0020] As used in this application, the terms "at least one", "multiple", "each", "any", etc., "at least one" includes one, two or more, "multiple" includes two or more, "each" refers to each of the corresponding multiples, and "any" refers to any one of the multiples.
[0021] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used herein is for the purpose of describing embodiments of this application only and is not intended to limit this application.
[0022] Currently, modal testing is the primary means of obtaining dynamic parameters such as the natural frequencies, damping, and mode shapes of a structure, and it is widely used in aerospace, automotive, and machinery manufacturing industries.
[0023] In related technologies, during actual testing, the springs in modal testing instruments, as support and excitation elements, are often affected by stress concentration. That is, when the spring is subjected to force, stress concentration is easily generated at the ends and support points, leading to local plastic deformation, which affects the elastic performance and stability of the spring, thereby affecting the accuracy and reliability of the modal test results.
[0024] In view of this, this application provides a high-precision modal testing method and related equipment. By introducing stress field quantification constraints during the spring design stage of the modal testing instrument, the characteristic parameters of the spring of the modal testing instrument are evaluated, which can effectively improve the design accuracy and reliability of the spring of the modal testing instrument, significantly reduce the spring design iteration cycle, improve the accuracy and stability of modal testing, and effectively meet the design requirements of high-reliability springs.
[0025] The specific implementation methods of the embodiments of this application will be described in detail below with reference to the accompanying drawings. First, a high-precision modal testing method provided in the embodiments of this application will be described with reference to the accompanying drawings.
[0026] Please refer to Figure 1 , Figure 1 This is a schematic diagram of the implementation environment for a high-precision modal testing method provided in this application embodiment. In this implementation environment, the main hardware and software components involved include a terminal processor 110 and a server 120.
[0027] Specifically, the terminal processor 110 may be equipped with a control program for a high-precision modal testing method, and the server 120 serves as the backend server for this control program. The terminal processor 110 and the backend server 120 are connected via a communication link. The high-precision modal testing method provided in this embodiment can be executed on the terminal processor 110 side.
[0028] Server 120 can be a standalone physical server, a server cluster or distributed system composed of multiple physical servers, or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, CDN (Content Delivery Network), and big data and artificial intelligence platforms.
[0029] In addition, server 120 can also be a node server in a blockchain network.
[0030] The terminal processor 110 and the server 120 can establish a communication connection via a wireless network. This wireless network uses standard communication technologies and / or protocols. The network can be the Internet or any other network, including but not limited to a Local Area Network (LAN), Metropolitan Area Network (MAN), Wide Area Network (WAN), mobile, or any combination of wireless networks, private networks, or virtual private networks. Furthermore, these hardware and software components can use the same or different communication connection methods; this application does not impose specific limitations in this regard.
[0031] Of course, this is understandable. Figure 1 The implementation environment described in this application is only one of the optional application scenarios for the high-precision modal testing method provided in this embodiment. The actual application is not fixed. Figure 1 The software and hardware environment shown is not specifically limited in this application.
[0032] like Figure 2 As shown, Figure 2 This is a flowchart illustrating a high-precision modal testing method provided in an embodiment of this application, specifically including but not limited to steps 100 to 400.
[0033] Step 100: Obtain spring design parameters and initialize spring design variables.
[0034] In this embodiment of the application, the design requirements of the modal testing instrument spring can be obtained to determine the spring design parameters. For example, different functional requirements such as the mass of the test piece, target modal frequency, allowable modal frequency offset, target stiffness, working stroke, and rated load of the spring can be determined to determine the spring design parameters. The spring design variables are then initialized and calculated to generate the spring design variables of the modal testing instrument spring.
[0035] Understandably, once the spring design parameters are determined based on the spring design requirements in the early stages of the design process, they generally remain unchanged. However, the spring design variables, after initialization, can be continuously iterated and optimized during the design phase to improve the reliability of the spring design in modal testing instruments.
[0036] For example, obtaining spring design parameters and initializing the generation of spring design variables includes: In response to the input spring design requirements, obtain the spring design parameters; Based on the spring design parameters, the spring design variables are initialized and calculated. The spring design parameters include the mass of the test piece in the modal test, the target modal frequency, the allowable modal frequency offset, the target stiffness, the working stroke, the rated load, the constraints of the installation space, the shear modulus, the fatigue limit, and the stress field characteristic parameter constraint threshold; the spring design variables include the effective number of coils, the mean diameter, the pitch, the radius of curvature, and the end grinding length.
[0037] In this embodiment of the application, by identifying the input spring design requirements, the spring design parameters can be further determined, specifically including the mass of the test piece for modal testing (the unit can be set to kg), the target modal frequency (the unit can be set to Hz), the allowable modal frequency offset, the target stiffness (the unit can be set to N / mm), the working stroke (the unit can be set to mm), the rated load (the unit can be set to N), the constraints of the installation space (e.g., the maximum outer diameter and the maximum free height limit), the shear modulus, the fatigue limit, and the stress field characteristic parameter constraint threshold.
[0038] Optionally, the constraint thresholds for stress field characteristic parameters can be set with upper limits for local stress gradient, high stress zone volume ratio, fretting risk, support stiffness matching coefficient, and support stiffness matching coefficient, to facilitate the setting of stress field constraint conditions. Specifically, the upper limit for local stress gradient can be set to 500 MPa / mm, the upper limit for high stress zone volume ratio can be set to 0.05, the upper limit for fretting risk can be set to 0.3, the upper limit for support stiffness matching coefficient can be set to 1.2, and the lower limit for support stiffness matching coefficient can be set to 0.8.
[0039] It is understandable that the upper limit threshold of local stress gradient, the upper limit threshold of high stress zone volume ratio, the upper limit threshold of fretting risk, the upper limit threshold of support stiffness matching coefficient, and the lower limit threshold of support stiffness matching coefficient can also be set according to the specific application scenario requirements, and this application does not impose specific restrictions on them.
[0040] Furthermore, by determining the obtained spring design parameters, the spring design variables are initialized and calculated. Specifically, the spring design variables include the effective number of coils, mean diameter, pitch, radius of curvature, and end grinding length.
[0041] The number of effective revolutions can be calculated using the following formula (1): (1) Where n is the effective number of turns; G is the shear modulus; d is the diameter of the spring wire used to produce the spring; and S is the working stroke. The mean diameter of the spring can be used as the maximum outer diameter. And the spring wire diameter d is calculated as follows, i.e. F represents the rated load.
[0042] Furthermore, the mean diameter D is taken from the mean diameter of the spring. ,Right now D = The pitch can be calculated using the following formula (2): (2) in, Pitch; This is the maximum free height limit.
[0043] Furthermore, the radius of curvature R can be calculated based on the diameter of the spring wire, i.e., R=0.6d; in addition, the end grinding length refers to the length of the area where the end of the helical spring is ground flat, which can be initially set to 270°.
[0044] In practical applications, the initial spring design variables can be quickly obtained based on historical product parameters, thereby improving spring design efficiency.
[0045] Step 200: Based on the spring design parameters and the spring design variables, calculate the stress field characteristic parameters.
[0046] In this embodiment, the stress field characteristic parameters of the spring are calculated based on the determined spring design parameters and spring design variables. By introducing stress field quantification constraints (local stress gradient, volume ratio of high stress area, fretting risk index, etc.) in the early stage of design, the rework and adjustment due to key failure factors during later optimization are avoided, which effectively improves the accuracy and efficiency of spring design and significantly reduces the design iteration time.
[0047] Optionally, as an optional implementation, the calculation of stress field characteristic parameters based on the spring design parameters and the spring design variables includes: Calculate the Wahl correction factor based on the spring winding ratio; Based on the aforementioned Wahl correction factor, the maximum shear stress is determined, thereby calculating the maximum value of the local stress gradient; Based on the three-dimensional stress attenuation model, combined with the maximum shear stress and fatigue limit, the volume ratio of the high-stress zone is calculated. The risk of fretting is calculated based on the contact pressure and slip amplitude. The target equivalent stiffness is calculated based on the offset between the target modal frequency and the allowable modal frequency. The equivalent linearized stiffness is calculated based on the spring stiffness. The support stiffness matching coefficient is calculated based on the target equivalent stiffness and the equivalent linearized stiffness. The calculation results of the maximum value of the local stress gradient, the volume ratio of the high-stress zone, the fretting risk, and the support stiffness matching coefficient are obtained and used as the stress field characteristic parameters.
[0048] In this embodiment, the stress field characteristic parameters mainly include the maximum value of local stress gradient, the volume ratio of high stress area, fretting risk, and support stiffness matching coefficient. By calculating the stress field characteristic parameters, it is possible to evaluate the stress field characteristic parameters in the future, thereby reducing the occurrence of excessive local stress when the spring is working.
[0049] Among them, the Waal correction coefficient is calculated. and maximum shear stress The maximum value of the local stress gradient can be calculated. The calculation process of the Waal correction coefficient is shown in the following formula (3): (3) in, is the Waal correction factor; C is the spring winding ratio, which is the ratio of the spring mean diameter to the spring wire diameter, specifically expressed as C=D / d.
[0050] Furthermore, based on the Wahl correction factor, the maximum shear stress can be calculated using the following formula (4): (4) in, This represents the maximum shear stress. This is the Val correction factor.
[0051] Finally, the maximum local stress gradient is calculated based on the ratio of the maximum shear stress to the radius of curvature. .
[0052] Furthermore, based on the three-dimensional stress attenuation model, combined with the maximum shear stress and fatigue limit, the volume ratio of the high-stress zone is calculated using the following formula (5): (5) in, The volume percentage of the high-stress zone; This represents the fatigue limit.
[0053] Furthermore, by calculating the contact pressure and slip amplitude, the fretting risk can be further calculated.
[0054] The contact pressure can be calculated using the following formula (6), and the slip amplitude can be calculated using the following formula (7): (6) (7) in, For contact pressure; The length of the end that has been ground flat; The slip amplitude is ΔF = 0.3F. For tangential stiffness, specifically expressed as .
[0055] Furthermore, the risk of micro-motion can be calculated using the following formula (8): (8) Where FI represents the fretting risk; μ is the friction coefficient, which can be set to 0.15 for example.
[0056] Furthermore, the equivalent linearized stiffness is calculated by summing the stiffnesses of all parallel springs, the target equivalent stiffness is calculated by the offset between the target modal frequency and the allowable modal frequency, and finally the support stiffness matching coefficient is determined based on the ratio of the equivalent linearized stiffness to the target equivalent stiffness.
[0057] The target equivalent stiffness can be calculated using the following formula (9): (9) in, The target equivalent stiffness; To allow modal frequency offset; To test the quality of the test piece using modal testing; The target modal frequency.
[0058] Furthermore, the support stiffness matching coefficient can be calculated using the following formula (10): (10) in, To support the stiffness matching coefficient; To achieve equivalent linearized stiffness; The target is the equivalent stiffness.
[0059] Ultimately, by obtaining the calculation results of the maximum local stress gradient, the volume ratio of the high-stress zone, the fretting risk, and the support stiffness matching coefficient, the stress field characteristic parameters of the modal testing instrument spring can be quickly obtained as three major failure driving indicators.
[0060] Step 300: Evaluate the stress field characteristic parameters based on the preset stress field constraint conditions.
[0061] In this embodiment, stress field constraint conditions can be set according to predetermined stress field characteristic parameter constraint thresholds, namely, the upper limit threshold of local stress gradient, the upper limit threshold of high stress zone volume ratio, and the upper limit threshold of fretting risk. For example, the stress field constraint conditions can be set as follows: the stress field characteristic parameters need to simultaneously satisfy the local stress gradient... High stress zone volume ratio The risk of micro-motion is FI ≤ 0.3 and the support stiffness matching coefficient is 0.8 ≤ ≤1.2.
[0062] In practical applications, during each design iteration verification process, the calculated stress field characteristic parameters, combined with the pre-set stress field constraints, can be used to evaluate whether the stress field characteristic parameters meet the stress field constraints.
[0063] Therefore, after quickly calculating the stress field characteristic parameters using the above formula, the stress field characteristic parameters can be quickly evaluated based on the preset stress field constraints without the need for large-scale simulation.
[0064] Step 400: If the stress field characteristic parameters satisfy the stress field constraint conditions, output the spring design variables as the spring design result.
[0065] In this embodiment of the application, if it is determined that the stress field characteristic parameters meet the preset stress field constraint conditions, it indicates that the current spring design variables meet the design requirements, and the current spring design variables can be output as the spring design result, thereby completing the forward design process of the modal testing instrument spring.
[0066] Therefore, compared to traditional spring design, the preliminary design stage often fails to fully consider key failure factors such as stress concentration, fretting wear, and stress gradient. The selection of structural parameters (such as radius of curvature, transition length, pitch, etc.) relies on experience rather than quantitative constraints, which can easily lead to excessive local stress during spring operation. This application introduces quantitative constraints on the stress field in the early stage of design, avoiding rework and adjustments due to key failure factors during later optimization, significantly reducing design iteration time. At the same time, by using stress field characteristic parameters as design input, the limitations of experience-based design are avoided, which can effectively improve the design accuracy and reliability of springs for modal testing instruments, thereby effectively meeting the design requirements of high-reliability springs.
[0067] Step 500: Prepare the spring based on the spring design results, and perform modal testing using the spring.
[0068] In this embodiment of the application, the spring can be prepared by the spring design result obtained in the above steps. When multiple springs are required for modal testing, the springs can be connected in parallel to complete the modal testing of the test piece.
[0069] For example, please refer to Figure 3 , Figure 3This is a schematic diagram of a high-precision modal test provided in an embodiment of this application. The modal test process of the test piece is completed by connecting the test piece to multiple springs. The springs prepared according to the spring design results have high stability and reliability in the modal test process, which can effectively improve the accuracy and stability of the modal test.
[0070] Specifically, as an optional implementation, the method further includes: If the stress field characteristic parameters do not meet the stress field constraint conditions, the spring design variables are corrected based on the preset correction rules, and the stress field characteristic parameters are recalculated. The recalculated stress field characteristic parameters are evaluated based on the preset stress field constraints.
[0071] In this embodiment, when the stress field characteristic parameters do not meet the stress field constraint conditions, it indicates that the current spring design variables do not meet the design requirements. The spring design variables can be further corrected based on the preset correction rules. After correcting the spring design variables, the stress field characteristic parameters are recalculated, and the recalculated stress field characteristic parameters are evaluated again to see if they meet the stress field constraint conditions. If they do, the spring design variables are output as the spring design result. If they do not meet, the above correction-evaluation steps are iterated.
[0072] For example, the correction of the spring design variables based on preset correction rules includes: The stress field characteristic parameters include the maximum local stress gradient, the volume ratio of the high-stress zone, the risk of fretting, and the support stiffness matching coefficient. If the maximum value of the local stress gradient is greater than the upper limit threshold of the local stress gradient, increase the radius of curvature and / or increase the end grinding length; If the volume ratio of the high-stress zone is greater than the upper limit threshold of the high-stress zone volume ratio, the effective number of rings is increased; If the micro-motion risk exceeds the upper limit threshold of the micro-motion risk, increase the pitch; If the support stiffness matching coefficient is greater than the upper limit threshold of the support stiffness matching coefficient, increase the mean diameter and / or decrease the spring wire diameter; If the support stiffness matching coefficient is less than the lower limit threshold of the support stiffness matching coefficient, reduce the mean diameter and / or increase the spring wire diameter.
[0073] In this embodiment of the application, when the maximum value of the local stress gradient is greater than the upper threshold of the local stress gradient, it can be corrected by increasing the radius of curvature, for example... ,in, The radius of curvature before correction. The corrected radius of curvature, or ,in, This refers to the corrected end grinding length.
[0074] In practical applications, if a problem is detected after each correction of the radius of curvature... This can terminate the correction rule on the radius of curvature, preventing structural interference. Furthermore, by increasing the correction rule on the end grinding length, the maximum end grinding length can also be set to no more than 340°.
[0075] Furthermore, when the volume ratio of the high-stress zone exceeds the upper limit threshold for the volume ratio of the high-stress zone, this can be corrected by increasing the number of effective cycles, for example, ,in, This is the corrected number of valid laps.
[0076] In practical applications, after each correction of the effective number of turns, if it is detected that the spring exceeds the maximum free height limit, If necessary, an auxiliary support ring can be added, that is, a 30° wedge angle can be embedded in the end 1.5 rings.
[0077] Furthermore, when the micro-motion risk exceeds the upper limit threshold, it can be corrected by increasing the pitch, for example, ,in, This is the corrected pitch.
[0078] In practical applications, if a problem is detected after each pitch correction... If so, a lubrication groove solution can be used, that is, a lubrication groove is added to the end of the spring.
[0079] Furthermore, when the support stiffness matching coefficient is greater than the upper limit threshold of the support stiffness matching coefficient, the number of parallel springs can be reduced or the spring mean diameter can be increased.
[0080] In practical applications, if space is limited, the stiffness matching coefficient of the support can be adjusted by reducing the diameter of the spring wire.
[0081] Furthermore, when the support stiffness matching coefficient is less than the lower limit threshold of the support stiffness matching coefficient, the number of parallel springs can be increased or the spring mean diameter can be reduced.
[0082] In practical applications, the stiffness matching coefficient of the support can also be constrained and corrected by adjusting and increasing the diameter of the spring wire.
[0083] Therefore, this application uses preset correction rules to automatically adjust the spring design variables within a reasonable range, ensuring that each iteration converges in the direction of constraint satisfaction, thereby improving the reliability of the spring design.
[0084] Specifically, as an optional implementation, after outputting the spring design variables as the spring design result, the method further includes: Based on the spring design results, Monte Carlo load tests and fatigue life verification were conducted to obtain the reliability verification results of the spring design results.
[0085] In the embodiments of this application, please refer to Figure 4 , Figure 4 This is a flowchart illustrating a high-precision modal test correction method provided in this application embodiment. By pre-setting stress field constraints, namely the upper limit threshold of local stress gradient, the upper limit threshold of high stress zone volume ratio, the upper limit threshold of fretting risk, the upper limit threshold of support stiffness matching coefficient, and the lower limit threshold of support stiffness matching coefficient, the spring design parameters are determined by obtaining the spring design requirements, and the spring design variables are initialized and calculated, thereby calculating the stress field characteristic parameters. Based on the preset stress field constraints, the stress field characteristic parameters are evaluated to determine whether they meet the stress field constraints.
[0086] Furthermore, when the stress field characteristic parameters do not meet the stress field constraint conditions, the spring design variables are modified based on preset correction rules. For example, the radius of curvature and / or the end grinding length is increased, the effective number of coils is increased, the pitch is increased, and the mean diameter and spring wire diameter are adjusted until the stress field characteristic parameters meet the stress field constraint conditions. When the stress field characteristic parameters meet the stress field constraint conditions, the reliability verification test of the output spring design results can also be performed. Specifically, the reliability of the spring design results can be verified by Monte Carlo load test and fatigue life verification, respectively.
[0087] Among them, when conducting Monte Carlo load tests, multiple sets of random load spectra can be generated, and stress field characteristic parameters can be calculated for each set of load spectra. The pass rate can be statistically analyzed to see if a preset threshold is met. When verifying fatigue life, the fatigue life of the spring can be calculated based on the Gerber-modified fatigue life model, and compared with the target life of the spring design to check whether the life meets the requirements.
[0088] Therefore, under the premise of meeting all constraints, the spring design results are ensured to be both reliable and meet performance and space requirements through dual reliability verification tests of statistics and life.
[0089] In practical applications, when the reliability verification results of the spring design fail, it can be corrected by increasing the diameter d of the spring wire. The correction process for the spring wire diameter d can be expressed as follows: ,in, The corrected spring wire diameter is k, which is the correction factor. It can be set according to the pass rate of the Monte Carlo load test. For example, when the pass rate is between 90% and 95%, k is set to 1.05; when the pass rate is between 80% and 90%, k is set to 1.1; and when the pass rate is less than 80%, k is set to 1.15.
[0090] Furthermore, increasing the diameter of the spring wire will significantly increase the spring's stiffness and compression height. Therefore, the stiffness of the spring can be compensated by adjusting the effective number of coils n, and the stress field characteristic parameters can be recalculated and verified.
[0091] The high-precision modal testing method provided in this invention will be explained and described in detail below, with reference to specific application implementation procedures: This application provides a high-precision modal testing method that can be applied to the spring design scenario of modal testing instruments. By introducing stress field quantification constraints during the spring design stage of modal testing instruments, the characteristic parameters of the springs in modal testing instruments can be evaluated, which can effectively improve the design accuracy and reliability of springs in modal testing instruments, significantly reduce the spring design iteration cycle, improve the accuracy and stability of modal testing, and effectively meet the design requirements of high-reliability springs.
[0092] Specifically, the design requirements of the modal testing instrument's spring can be obtained to determine the spring's design parameters. For example, different functional requirements such as the mass of the test piece, target modal frequency, allowable modal frequency offset, target stiffness, working stroke, and rated load can be determined. These parameters allow for the determination of the spring's design parameters, and initial calculations can be performed on the spring's design variables to generate the spring design variables for the modal testing instrument. For example, by identifying the input spring design requirements, the spring design parameters can be further determined, specifically including the mass of the modal test specimen (the unit can be set to kg), the target modal frequency (the unit can be set to Hz), the allowable modal frequency offset, the target stiffness (the unit can be set to N / mm), the working stroke (the unit can be set to mm), the rated load (the unit can be set to N), the constraints of the installation space (e.g., the maximum outer diameter and the maximum free height limit), the shear modulus, the fatigue limit, and the stress field characteristic parameter constraint threshold.
[0093] Optionally, the stress field characteristic parameter constraint thresholds can be set with an upper limit threshold for local stress gradient, an upper limit threshold for the volume ratio of high stress zone, an upper limit threshold for fretting risk, an upper limit threshold for support stiffness matching coefficient, and a lower limit threshold for support stiffness matching coefficient, so as to facilitate the setting of stress field constraint conditions.
[0094] Furthermore, based on the determined spring design parameters and spring design variables, the stress field characteristic parameters of the spring are calculated. Stress field constraint conditions are set according to the predetermined stress field characteristic parameter constraint thresholds, namely the upper limit threshold of local stress gradient, the upper limit threshold of high stress zone volume ratio, the upper limit threshold of fretting risk, the upper limit threshold of support stiffness matching coefficient, and the lower limit threshold of support stiffness matching coefficient, and the stress field characteristic parameters are evaluated.
[0095] Among them, the stress field characteristic parameters mainly include the maximum value of local stress gradient, the volume ratio of high stress area, fretting risk, and support stiffness matching coefficient. By calculating the stress field characteristic parameters, it is possible to evaluate the stress field characteristic parameters in the future, thereby reducing the occurrence of excessive local stress when the spring is working.
[0096] Furthermore, if the stress field characteristic parameters are determined to meet the preset stress field constraint conditions, it indicates that the current spring design variables meet the design requirements. The current spring design variables can then be output as the spring design result, thus completing the forward design process of the modal testing instrument spring. If the stress field characteristic parameters do not meet the stress field constraint conditions, it indicates that the current spring design variables do not meet the design requirements. The spring design variables can then be further corrected based on preset correction rules. After correcting the spring design variables, the stress field characteristic parameters are recalculated, and the recalculated stress field characteristic parameters are re-evaluated to see if they meet the stress field constraint conditions. If they do, the spring design variables are output as the spring design result; otherwise, the correction-evaluation steps are iterated repeatedly.
[0097] Finally, the reliability of the output spring design results is verified by testing, specifically through Monte Carlo load testing and fatigue life verification.
[0098] Please see Figure 5 , Figure 5 This is a schematic diagram of a high-precision modal testing device provided in an embodiment of this application. This application also provides a high-precision modal testing device that can implement the above-mentioned high-precision modal testing method. The device includes: The parameter acquisition module 510 is used to acquire spring design parameters and initialize and generate spring design variables. The parameter calculation module 520 is used to calculate the stress field characteristic parameters based on the spring design parameters and the spring design variables; The parameter evaluation module 530 is used to evaluate the stress field characteristic parameters based on preset stress field constraint conditions. The parameter output module 540 is used to output the spring design variables as the spring design result when the stress field characteristic parameters satisfy the stress field constraint conditions. Modal testing module 550 is used to prepare the spring based on the spring design results and to perform modal testing on the spring.
[0099] It is understood that the content of the above method embodiments is applicable to the present device embodiments. The specific functions implemented by the present device embodiments are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.
[0100] Please see Figure 6 , Figure 6 This is a schematic diagram of the hardware structure of an electronic device provided in an embodiment of this application. The electronic device includes: The processor 601 can be implemented using a general-purpose CPU (Central Processing Unit), microprocessor, application-specific integrated circuit (ASIC), or one or more integrated circuits, and is used to execute relevant programs to implement the technical solutions provided in the embodiments of this application. The memory 602 can be implemented as a read-only memory (ROM), a static storage device, a dynamic storage device, or a random access memory (RAM). The memory 602 can store the operating system and other applications. When the technical solutions provided in the embodiments of this specification are implemented through software or firmware, the relevant program code is stored in the memory 602 and is called and executed by the processor 601 using the methods described in the embodiments of this application. The input / output interface 603 is used to implement information input and output; The communication interface 604 is used to enable communication and interaction between this device and other devices. Communication can be achieved through wired means (such as USB, network cable, etc.) or wireless means (such as mobile network, WIFI, Bluetooth, etc.). Bus 605 transmits information between various components of the device (e.g., processor 601, memory 602, input / output interface 603, and communication interface 604); The processor 601, memory 602, input / output interface 603, and communication interface 604 are connected to each other within the device via bus 605.
[0101] This application also provides a computer-readable storage medium storing a computer program that, when executed by a processor, implements the above-described method.
[0102] It is understood that the content of the above method embodiments is applicable to this storage medium embodiment. The specific functions implemented in this storage medium embodiment are the same as those in the above method embodiments, and the beneficial effects achieved are also the same as those achieved in the above method embodiments.
[0103] This application also provides a computer program product, including a computer program that, when executed by a processor, implements the above-described method.
[0104] It is understood that the content of the above method embodiments is applicable to the embodiments of this program product. The specific functions implemented by the embodiments of this program product are the same as those of the above method embodiments, and the beneficial effects achieved are also the same as those achieved by the above method embodiments.
[0105] Memory, as a non-transitory computer-readable storage medium, can be used to store non-transitory software programs and non-transitory computer-executable programs. Furthermore, memory may include high-speed random access memory, and may also include non-transitory memory, such as at least one disk storage device, flash memory device, or other non-transitory solid-state storage device. In some embodiments, memory may optionally include memory remotely located relative to the processor, and these remote memories can be connected to the processor via a network. Examples of such networks include, but are not limited to, the Internet, intranets, local area networks, mobile communication networks, and combinations thereof.
[0106] This application provides a high-precision modal testing method and related equipment. By introducing stress field quantification constraints during the spring design stage of the modal testing instrument, the characteristic parameters of the spring in the modal testing instrument are evaluated. This can effectively improve the design accuracy and reliability of the spring in the modal testing instrument, significantly reduce the spring design iteration cycle, improve the accuracy and stability of modal testing, and effectively meet the design requirements of high-reliability springs.
[0107] The embodiments described in this application are for the purpose of more clearly illustrating the technical solutions of the embodiments of this application, and do not constitute a limitation on the technical solutions provided by the embodiments of this application. As those skilled in the art will know, with the evolution of technology and the emergence of new application scenarios, the technical solutions provided by the embodiments of this application are also applicable to similar technical problems.
[0108] Those skilled in the art will understand that the technical solutions shown in the figures do not constitute a limitation on the embodiments of this application, and may include more or fewer steps than shown, or combine certain steps, or different steps.
[0109] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs.
[0110] Those skilled in the art will understand that all or some of the steps in the methods disclosed above, as well as the functional modules / units in the systems and devices, can be implemented as software, firmware, hardware, or suitable combinations thereof.
[0111] The terms “first,” “second,” “third,” “fourth,” etc. (if present) in the specification and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of this application described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms “comprising” and “having,” and any variations thereof, are intended to cover non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.
[0112] It should be understood that in this application, "at least one (item)" means one or more, and "more than" means two or more. "And / or" is used to describe the relationship between related objects, indicating that three relationships can exist. For example, "A and / or B" can represent three cases: only A exists, only B exists, and both A and B exist simultaneously, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects are in an "or" relationship. "At least one (item) of the following" or similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one (item) of a, b, or c can represent: a, b, c, "a and b", "a and c", "b and c", or "a and b and c", where a, b, and c can be single or multiple.
[0113] In the several embodiments provided in this application, it should be understood that the disclosed apparatus and methods can be implemented in other ways. For example, the apparatus embodiments described above are merely illustrative; for instance, the division of the units described above is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces; the indirect coupling or communication connection between apparatuses or units may be electrical, mechanical, or other forms.
[0114] The units described above as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.
[0115] Furthermore, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.
[0116] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes multiple instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods of the various embodiments of this application. The aforementioned storage medium includes various media capable of storing programs, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.
[0117] The preferred embodiments of the present application have been described above with reference to the accompanying drawings, but this does not limit the scope of the claims of the present application. Any modifications, equivalent substitutions, and improvements made by those skilled in the art without departing from the scope and substance of the embodiments of the present application shall be within the scope of the claims of the present application.
Claims
1. A high-precision modal testing method, characterized in that, The method includes the following steps: Obtain spring design parameters and initialize spring design variables; Based on the spring design parameters and the spring design variables, the stress field characteristic parameters are calculated. The stress field characteristic parameters are evaluated based on the preset stress field constraints. If the stress field characteristic parameters satisfy the stress field constraint conditions, the spring design variables are output as the spring design result. A spring is fabricated based on the spring design results, and modal testing is performed using the spring.
2. The method according to claim 1, characterized in that, The process of obtaining spring design parameters and initializing spring design variables includes: In response to the input spring design requirements, obtain the spring design parameters; Based on the spring design parameters, the spring design variables are initialized and calculated. The spring design parameters include the mass of the test piece in the modal test, the target modal frequency, the allowable modal frequency offset, the target stiffness, the working stroke, the rated load, the constraints of the installation space, the shear modulus, the fatigue limit, and the stress field characteristic parameter constraint threshold; the spring design variables include the effective number of coils, the mean diameter, the pitch, the radius of curvature, and the end grinding length.
3. The method according to claim 1, characterized in that, The stress field characteristic parameters calculated based on the spring design parameters and the spring design variables include: Calculate the Val correction factor based on the spring winding ratio; Based on the aforementioned Wahl correction factor, the maximum shear stress is determined, thereby calculating the maximum value of the local stress gradient; Based on the three-dimensional stress attenuation model, combined with the maximum shear stress and fatigue limit, the volume ratio of the high-stress zone is calculated. The risk of fretting is calculated based on the contact pressure and slip amplitude. The target equivalent stiffness is calculated based on the offset between the target modal frequency and the allowable modal frequency. The equivalent linearized stiffness is calculated based on the spring stiffness. The support stiffness matching coefficient is calculated based on the target equivalent stiffness and the equivalent linearized stiffness. The calculation results of the maximum value of the local stress gradient, the volume ratio of the high-stress zone, the fretting risk, and the support stiffness matching coefficient are obtained and used as the stress field characteristic parameters.
4. The method according to claim 1, characterized in that, The method further includes: If the stress field characteristic parameters do not meet the stress field constraint conditions, the spring design variables are corrected based on the preset correction rules, and the stress field characteristic parameters are recalculated. The recalculated stress field characteristic parameters are evaluated based on the preset stress field constraints.
5. The method according to claim 4, characterized in that, The correction of the spring design variables based on the preset correction rules includes: The stress field characteristic parameters include the maximum local stress gradient, the volume ratio of the high-stress zone, the risk of fretting, and the support stiffness matching coefficient. If the maximum value of the local stress gradient is greater than the upper limit threshold of the local stress gradient, increase the radius of curvature and / or increase the end grinding length; If the volume ratio of the high-stress zone is greater than the upper limit threshold of the high-stress zone volume ratio, the effective number of rings is increased; If the micro-motion risk exceeds the upper limit threshold of the micro-motion risk, increase the pitch; If the support stiffness matching coefficient is greater than the upper limit threshold of the support stiffness matching coefficient, increase the mean diameter and / or decrease the spring wire diameter; If the support stiffness matching coefficient is less than the lower limit threshold of the support stiffness matching coefficient, reduce the mean diameter and / or increase the spring wire diameter.
6. The method according to claim 1, characterized in that, After outputting the spring design variables as the spring design result, the following is also included: Based on the spring design results, Monte Carlo load tests and fatigue life verification were conducted to obtain the reliability verification results of the spring design results.
7. A high-precision modal testing device, characterized in that, The device includes: The parameter acquisition module is used to acquire spring design parameters and initialize and generate spring design variables; The parameter calculation module is used to calculate the stress field characteristic parameters based on the spring design parameters and the spring design variables. The parameter evaluation module is used to evaluate the characteristic parameters of the stress field based on preset stress field constraints. The parameter output module is used to output the spring design variables as the spring design result when the stress field characteristic parameters satisfy the stress field constraint conditions. The modal testing module is used to prepare the spring based on the spring design results and to perform modal testing on the spring.
8. An electronic device, characterized in that, The electronic device includes a memory and a processor, the memory storing a computer program, and the processor executing the computer program to implement the method according to any one of claims 1 to 6.
9. A computer-readable storage medium storing a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 6.
10. A computer program product, comprising a computer program, characterized in that, When the computer program is executed by a processor, it implements the method of any one of claims 1 to 6.