Method and system for batch mechanical testing of slender rod structure products

Abstract

The present invention provides a method and system for batch mechanical testing of slender rod structure products, including: Step S1, determining the quantity of batch mechanical testing of products according to the production rhythm; Step S2, determining the minimum installation gap between products according to the simulation results of mechanical testing; Step S3, determining the actual installation state of products, and keeping the fixed state of the clamping device consistent with the actual installation state of products; Step S4, determining the mechanical testing clamping device and producing it; Step S5, conducting a preliminary test on the clamping device before the test starts, ensuring that the structural strength meets the requirements and the products are reliably connected to the clamping device. The present invention calculates the quantity of products for batch mechanical testing of slender rod structure products in combination with actual production, and ensures that multiple products meet the requirements of mechanical testing through a reasonable mechanical testing clamping device, which helps to improve the test efficiency, reduce the production cost, shorten the production cycle, and improve the delivery capacity.

Description

Technical Field

[0001] The present invention relates to the field of electronic manufacturing technology, and specifically, to a method and system for batch mechanical testing of products with an elongated rod structure. Background Art

[0002] The existing mechanical testing technology for products with an elongated rod structure connects a single product to a mechanical testing device through a clamping device. There is no clear testing method, and there is a situation where the product is damaged due to single-end clamping of the product, which cannot meet the testing cycle of batch production of products.

[0003] Therefore, a method that can ensure reliable product quality while shortening the mechanical testing cycle is needed to enable simultaneous mechanical testing of multiple products with an elongated rod structure. Summary of the Invention

[0004] Aiming at the defects in the prior art, the purpose of the present invention is to provide a method and system for batch mechanical testing of products with an elongated rod structure.

[0005] According to the method for batch mechanical testing of products with an elongated rod structure provided by the present invention, it includes:

[0006] Step S1: Dynamically adjust the batch quantity according to the production rhythm, and use a rolling optimization algorithm based on real-time data acquisition to determine the maximum test batch by comprehensively considering the equipment fatigue coefficient and material creep characteristics;

[0007] Step S2: Establish a multi-physical field coupling finite element model, use a non-linear contact algorithm to simulate the product swing amplitude, iteratively optimize the installation gap through a parameter inversion method, and set a three-dimensional laser scan to verify that the actual gap and the simulation deviation are <0.5 mm;

[0008] Step S3: Construct a virtual clamping system based on digital twin, use a six-axis force sensor to monitor the clamping state in real time, and make the pre-tightening force fluctuation <±2% through PID closed-loop control, and the surface roughness Ra of the clamping surface ≤3.2 m and the contact area ≥85%;

[0009] Step S4: Develop a modular adaptive fixture system, including a piezoelectric ceramic-driven dynamic damper with a frequency response range of 5 Hz - 500 Hz; a variable stiffness support arm with a stiffness adjustment ratio ≥10:1, and use topology optimization design;

[0010] Step S5: Establish a clamping quality detection system based on machine vision, identify connection defects through a convolutional neural network, use acoustic emission technology to monitor structural damage in real time, and set a dual-redundancy safety interlock mechanism.

[0011] Preferably, in step S1, the batch quantity is dynamically adjusted according to the production rhythm, and the formula is: Z=A÷(T÷t), where t is the single mechanical test time, T is the mechanical test production cycle, and A is the total product volume;

[0012] The dynamic correction coefficient η is introduced, ranging from 0.8 to 1.2, and the calculation formula is optimized as follows: Z = η × [A ÷ (T / (t + t))], where t is the equipment cooling time and t=0.1t× , N is the cumulative number of tests; set the infrared thermal imager to monitor the temperature rise of the equipment in real time. When T>15℃, η value correction is automatically triggered.

[0013] Preferably, in step S3, the fixing state of the clamping device is kept consistent with the actual installation state of the product, including the strength of the clamping device, the preload force of the connection interface and the edge condition of the product fixation, wherein the resonance point of the clamping device is consistent with the actual state, and the tension force and angle of the soft connection part are consistent with the actual state;

[0014] The specific implementation includes: using swept frequency vibration testing to ensure that the deviation between the first three natural frequencies of the clamping device and the product installation base is <±3%; setting a preload gradient loading system with a loading rate of ≤50N / s, and monitoring the interface stress distribution through a fiber grating sensor array with a spatial resolution of 1cm; establishing an edge condition digital twin database to store ≥100 sets of typical working condition parameter combinations.

[0015] Preferably, in step S3, the actual installation state of the slender rod structure product is: one end is fixed by a clamp and rigidly connected to the structural member, and the other end is fixed by a clamp and tightened and fixed by three steel wire ropes distributed at 120°, and the angle between the steel wire rope and the product is 90°. The above conditions need to be considered in the design of the clamping device, and the tensioning force of the steel wire rope and the material of the clamping device are consistent with the actual state;

[0016] Building a virtual clamping system based on digital twins includes: developing a bionic clamp with self-sensing function, built-in MEMS accelerometer and strain gauge, using magnetorheological intelligent rope for wire rope tension, adjusting the response time <50ms, setting up a binocular vision system to measure the angle deviation in real time with an accuracy of ±0.1°, and automatically compensating for the thermal expansion coefficient of the material when the temperature fluctuates >±5℃.

[0017] Preferably, in step S4, the fixing methods of the two ends of the product are inconsistent, one end is rigidly connected, and the other end is non-rigidly connected, and the products are 180° symmetrically distributed; in the product testing phase, the electrical environment of the environment in which the equipment is located is tested, and if the actual environment does not meet the preset requirements, an electrical environment that meets the preset requirements is created by connecting an isolation transformer to the front end of the product;

[0018] The electrical environment simulation is as follows: a three-degree-of-freedom hydraulic shaker is set at the non-rigid end with a displacement accuracy of ±0.01 mm; an electromagnetic shielding chamber is constructed with a shielding effectiveness of ≥80 dB @ 10 MHz - 1 GHz; the isolation transformer adopts a double shielding structure with a leakage magnetic flux of <1 T; a power quality analyzer is set with a THD of <3%; a grounding resistance monitoring device is set with a resistance value of <0.1 Ω.

[0019] According to the system for batch mechanical testing of slender rod structure products provided by the present invention, it includes:

[0020] Module M1: Dynamically adjust the batch quantity according to the production rhythm, adopt a rolling optimization algorithm based on real-time data acquisition, and determine the maximum test batches by comprehensively considering the equipment fatigue coefficient and material creep characteristics;

[0021] Module M2: Establish a multi-physical-field coupling finite element model, simulate the product swing amplitude using a non-linear contact algorithm, iteratively optimize the installation gap through the parameter inversion method, and set a three-dimensional laser scan to verify that the deviation between the actual gap and the simulation is <0.5 mm;

[0022] Module M3: Construct a virtual clamping system based on digital twin, use a six-axis force sensor to monitor the clamping state in real time, and make the pre-tightening force fluctuation <±2% through PID closed-loop control, with the clamping surface roughness Ra ≤ 3.2 μm and the contact area ≥ 85%;

[0023] Module M4: Develop a modular adaptive fixture system, including a piezoelectric ceramic-driven dynamic damper with a frequency response range of 5 Hz - 500 Hz; a variable stiffness support arm with a stiffness adjustment ratio of ≥10:1, and adopt a topology optimization design;

[0024] Module M5: Establish a clamping quality detection system based on machine vision, identify connection defects through a convolutional neural network, use acoustic emission technology to monitor structural damage in real time, and set a dual-redundancy safety interlock mechanism.

[0025] Preferably, in the module M1, the batch quantity is dynamically adjusted according to the production rhythm, and the formula is: Z = A ÷ (T ÷ t), where t is the time of a single mechanical test, T is the production cycle of the mechanical test, and A is the total quantity of products;

[0026] Introduce a dynamic correction coefficient η, with a range of 0.8 - 1.2, and the calculation formula is optimized to: Z = η × [A ÷ (T / (t + t))], where t is the equipment cooling time and t = 0.1t × , N is the cumulative number of tests; set an infrared thermal imager to monitor the equipment temperature rise in real time, when When T>15℃, η value correction is automatically triggered.

[0027] Preferably, in the module M3, the fixing state of the clamping device is kept consistent with the actual installation state of the product, including the strength of the clamping device, the preload force of the connection interface and the edge condition of the product fixation, wherein the resonance point of the clamping device is consistent with the actual state, and the tension force and angle of the soft connection part are consistent with the actual state;

[0028] The specific implementation includes: using swept frequency vibration testing to ensure that the deviation between the first three natural frequencies of the clamping device and the product installation base is <±3%; setting a preload gradient loading system with a loading rate of ≤50N / s, and monitoring the interface stress distribution through a fiber grating sensor array with a spatial resolution of 1cm; establishing an edge condition digital twin database to store ≥100 sets of typical working condition parameter combinations.

[0029] Preferably, in the module M3, the actual installation state of the slender rod structure product is: one end is fixed by a clamp and rigidly connected to the structural member, and the other end is fixed by a clamp and tightened and fixed with three steel wire ropes distributed at 120°, and the angle between the steel wire rope and the product is 90°. The above conditions need to be considered in the design of the clamping device, and the tensioning force of the steel wire rope and the material of the clamping device should be consistent with the actual state;

[0030] Building a virtual clamping system based on digital twins includes: developing a bionic clamp with self-sensing function, built-in MEMS accelerometer and strain gauge, using magnetorheological intelligent rope for wire rope tension, adjusting the response time <50ms, setting up a binocular vision system to measure the angle deviation in real time with an accuracy of ±0.1°, and automatically compensating for the thermal expansion coefficient of the material when the temperature fluctuates >±5℃.

[0031] Preferably, in the module M4, the fixing methods of the two ends of the product are inconsistent, one end is rigidly connected, and the other end is non-rigidly connected, and the products are 180° symmetrically distributed; in the product testing phase, the electrical environment of the environment in which the equipment is located is tested. If the actual environment does not meet the preset requirements, an electrical environment that meets the preset requirements is created by connecting an isolation transformer to the front end of the product;

[0032] The electrical environment simulation is as follows: a three-degree-of-freedom hydraulic excitation table is set at the non-rigid end, with a displacement accuracy of ±0.01mm; an electromagnetic shielding room is constructed, with a shielding effectiveness of ≥80dB@10MHz-1GHz; the isolation transformer adopts a double shielding structure, with a leakage flux of <1 T; Set up a power quality analyzer, THD<3%; Set up a ground resistance monitoring device, resistance<0.1Ω.

[0033] Compared with the prior art, the present invention has the following beneficial effects:

[0034] (1)From the perspective of the full-cycle production of slender rod structure products, this invention integrates all aspects of product production, calculates the number of batch mechanical tests for slender rod structure products, determines the structure of the clamping device by clarifying three key factors: the installation clearance of the product, the fixing requirements, and the load-bearing capacity of the test equipment, and obtains the method for batch mechanical tests, which helps to ensure product quality, improve the efficiency of mechanical tests, optimize the production process, reduce production costs, and shorten the production cycle;

[0035] (2)By optimizing the production process and designing the clamping device, this invention solves the problem of low efficiency of mechanical tests for slender rod structure products, and helps to realize batch mechanical tests for more special-shaped structure products. Description of the Drawings

[0036] By reading the detailed description of the non-limiting embodiments with reference to the following drawings, other features, objectives, and advantages of the present invention will become more apparent:

[0037] Figure 1 It is a flowchart mainly showing step S1 in the present invention for determining the number of batch mechanical tests of slender rod structure products according to the production rhythm. Detailed Embodiments

[0038] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0039] Embodiment 1

[0040] As Figure 1 shown, the present invention provides a method applied to batch mechanical tests of slender rod structure products, including the following steps:

[0041] Step S1: Determine the number of batch mechanical tests of the product according to the production rhythm;

[0042] Step S2: Determine the minimum installation clearance between products according to the simulation results of mechanical tests;

[0043] Step S3: Determine the actual installation state of the product, and the fixed state of the clamping device is consistent with the actual installation state of the product;

[0044] Step S4: Determine and produce the mechanical test clamping device;

[0045] Step S5: Conduct a preliminary test on the clamping device before the test, the structural strength meets the requirements, and the product is reliably connected to the clamping device.

[0046] In view of the current situation of mechanical tests for products with slender rod structures, products with slender rod structures are generally cylindrical with a length of 1600 - 2400 mm and a diameter of 30 - 60 mm. Aiming to conduct mechanical tests on multiple products with slender rod structures simultaneously, a method for batch mechanical tests of products with slender rod structures is provided. Combining with production reality, the present invention accurately determines the batch quantity of products, reasonably designs the clamping device, and can realize the method for batch mechanical tests of products with slender rod structures, which can be widely applied.

[0047] In step S1, the calculation method for determining the quantity of products for batch mechanical tests is as follows: the single mechanical test time is t, the mechanical test production cycle is T, the total quantity of products is A, and the batch quantity Z = A÷(T÷t). The single mechanical test time t is determined by the mechanical test conditions and the difficulty of fixing the product and the clamping device; the mechanical test production cycle T is related to the total quantity of products A and is limited by the production cycle of the entire product. It is necessary to consider the maximum value of the batch quantity Z, balance T and A. At the same time, T and A should inversely restrict the rolling quantity and production cycle of the previous product assembly process; the maximum value of the batch quantity Z is related to the size of the mechanical test equipment installation surface and the installation distance around the equipment.

[0048] Taking the following data as an example in the present invention: the mechanical test production cycle is T = 4 h, the total quantity of products is 16, the single mechanical test time (including product installation, test, and test time) t = 0.5 h. It takes 8 h for 16 products to complete the test, which does not meet the requirements of the mechanical test production cycle. Using the method of batch mechanical tests and combining with the actual production situation, the batch quantity Z = 2 is determined. Combining with the full-cycle production of the product, to meet the demand of the production peak, the quantity of batch mechanical tests is determined to be 4.

[0049] In step S2, a geometric model consistent with the shape of the product with a slender rod structure is established in the drawing software, and the details that do not affect the mechanical behavior are removed to reduce the calculation amount of subsequent simulations; the elastic modulus, Poisson's ratio, density, and other properties are defined according to the actual material of the product; the element type is selected, and the mesh is encrypted in the area with stress concentration; with the actual mechanical test conditions of the product as the constraint conditions, the load is applied, and model simulation is carried out on the SolidWorks Simulation simulation tool. It is determined that the sway amplitude at the end of the product is about 36 mm, so the minimum installation gap between two products is determined to be 72 mm.

[0050] I. Refined model simulation process

[0051] 1. Geometric modeling and feature simplification

[0052] Parametric modeling using SolidWorks is adopted to establish a 1:1 three-dimensional solid model (modeling accuracy ±0.1 mm);

[0053] Remove non-load-bearing features such as threaded holes with a diameter < 3 mm and fillets with a chamfer radius < 1 mm (based on Saint-Venant's principle);

[0054] Retain key connection structures: flange contact surface (roughness Ra = 3.2 μm), clamp installation groove (width tolerance ±0.05 mm).

[0055] 2. Definition of material constitutive model

[0056] Input material properties:

[0057] Elastic modulus E = 210 GPa (typical value for alloy steel);

[0058] Poisson's ratio ν = 0.3 (empirical value for metallic materials);

[0059] Density ρ = 7850 kg / m³;

[0060] Yield strength σ_s = 355 MPa (refer to GB / T 3077 standard);

[0061] Establish a bilinear hardening model: tangent modulus E_t = 0.01E.

[0062] 3. Intelligent mesh generation strategy

[0063] Use hexahedral elements for the main body (element size 10 mm);

[0064] Use quadratic tetrahedral elements to refine the stress concentration areas (such as the clamp contact surface);

[0065] Refinement criterion: start adaptive refinement when the curvature change > 15°;

[0066] Mesh number calculation formula: N = k·(L / d)^3, where k = 1.2 is the refinement coefficient, L is the rod length of 2000 mm, and d is the element size;

[0067] The total number of meshes calculated is N ≈ 1.2×(2000 / 10)^3 = 9600000 elements.

[0068] 4. Boundary conditions and load settings

[0069] Constraint conditions:

[0070] Fixed end: constrain displacements and rotations in the X / Y / Z directions (UX = UY = UZ = ROTX = ROTY = ROTZ = 0);

[0071] Moving end: constrain radial displacements (UX = UY = 0), allow axial rotation (ROTZ is free);

[0072] Load application:

[0073] Lateral vibration load: F(t) = F_0·sin(2πft) (F_0 = 500 N, f = 25 Hz);

[0074] Axial pre-tightening force: P = 2000 N (simulated by bolt connection).

[0075] 5. Solution and post-processing

[0076] Using the Newton - Raphson iteration method (convergence tolerance 0.1%)

[0077] Key output parameters:

[0078] Maximum equivalent stress σ_max = 287 MPa < σ_s (safety factor n = 355 / 287 ≈ 1.24);

[0079] End displacement time history curve: Peak - to - peak value S_pp = 36 mm (corresponding amplitude A = 18 mm);

[0080] First - order natural frequency f_1 = 32.5 Hz (maintaining a 1.3 - fold interval from the excitation frequency of 25 Hz).

[0081] II. Implementation details of the mechanical test process

[0082] 1. Test preparation stage

[0083] Test bench configuration:

[0084] Three - axis vibration table (maximum thrust 20 kN, frequency range 5 - 2000 Hz)

[0085] Clamping device:

[0086] Rigid end: 42CrMo alloy steel clamp (hardness HRC50 - 55)

[0087] Flexible end: 304 stainless steel wire rope (diameter 8 mm, breaking strength ≥ 1570 MPa)

[0088] Environmental control:

[0089] Temperature: 23 ± 2 °C (PID temperature control system)

[0090] Humidity: 45 ± 5%RH (dehumidification unit)

[0091] 2. Dynamic loading implementation

[0092] Load spectrum design (referring to MIL - STD - 810G standard):

[0093] | Condition | Frequency (Hz) | Acceleration (g) | Duration (min) |

[0094] | Sweep Frequency | 5 - 500 | 1.5 | 15 |

[0095] | Fixed Frequency | 25 | 3.0 | 30 |

[0096] | Random | 20 - 2000 | 0.04 g² / Hz | 60 |

[0097] Dynamic clearance calculation formula:

[0098] D = , = 1.5 is the dynamic magnification factor;

[0099] Substituting S_static = 36 mm gives D = 108 mm. After taking a safety factor of 1.5, the final clearance is determined to be 72 mm.

[0100] 3. Data acquisition system

[0101] Sensor arrangement:

[0102] | Measurement Parameter | Sensor Type | Sampling Frequency | Arrangement Location |

[0103] | Acceleration | PCB 356A01 (±500 g) | 10 kHz | 50 mm from the end

[0104] | Strain | HBM LY41 (±5000 με) | 2 kHz | Middle of the rod

[0105] | Displacement | Keyence LK - H050 (±50 mm) | 1 kHz | Moving end

[0106] Synchronization trigger error < 1 μs (using IEEE 1588 Precision Clock Protocol)

[0107] 4. Test verification process

[0108] Pre - test (50% load):

[0109] Check the slip of the clamping device < 0.1 mm (verified by laser rangefinder)

[0110] Monitor the resonance frequency shift < ±2% (compared with simulation)

[0111] Formal test:

[0112] Adopt step - loading: 50% → 80% → 100% → 120% load

[0113] Each load level lasts for 10 minutes and data is recorded

[0114] Failure criterion (the test is terminated when any one of the conditions is met):

[0115] Residual deformation > 0.2%L (L = rod length)

[0116] Crack length > 5 mm (industrial endoscope inspection)

[0117] Change in frequency characteristics > 10%

[0118] III. Comparative verification of key parameters

[0119] | Parameter | Simulation value | Test value | Error |

[0120] | End displacement (mm) | 36.0 | 37.2 | +3.3% |

[0121] | First-order frequency (Hz) | 32.5 | 31.8 | -2.2% |

[0122] | Maximum stress (MPa) | 287 | 301 | +4.9% |

[0123] | Installation clearance (mm) | 72 | 75 (actual measurement requirement) | +4.2% |

[0124] Technical effect: Through refined modeling (error < 5%) and dynamic clearance calculation, the batch test efficiency is increased by 40% (previously single-piece testing was required), and at the same time, product interference is avoided (the measured minimum clearance of 75 mm > the theoretical value of 72 mm).

[0125] In step S3, the actual installation state of the slender rod structure product is that one end is rigidly connected to the structural member after being fixed by a clamp, and the other end is fixed by a clamp and then tightened and fixed by 3 steel wire ropes distributed at 120°. The included angle between the steel wire ropes and the product is 90°. When designing the clamping device, the above conditions need to be considered, and the tension of the steel wire ropes and the material of the clamping device are consistent with the actual state.

[0126] In step S4, the fixing methods at both ends of this product are inconsistent. One end is rigidly connected, and the other end is non-rigidly connected, with a sway amplitude of 36 mm. Therefore, when designing the clamping device, the products are symmetrically distributed at 180°. The minimum installation clearance of the product is reduced from 72 mm to 40 mm; due to the product length of 1600 - 2400 mm, the space around the test equipment can meet the flat placement of the product; at the same time, the product has relatively high requirements for the electrical environment of the equipment environment during the test. When the actual requirements are not met, a relatively pure electrical environment is created by connecting an isolation transformer at the front end of the product.

[0127] In step S5, before installing the product and the clamping device, the clamping device should be pre-tested to ensure its reliability. At the same time, wire harness fixing tie points are designed on the clamping device to protect the wire harness.

[0128] The present invention combines a method for calculating the number of batch mechanical tests of slender rod structure products in actual production, provides a method for designing a clamping device, and realizes batch mechanical tests of slender rod structure products.

[0129] Embodiment 2

[0130] The present invention also provides a system applied to batch mechanical tests of slender rod structure products. The system applied to batch mechanical tests of slender rod structure products can be realized by executing the process steps of the method applied to batch mechanical tests of slender rod structure products. That is, those skilled in the art can understand the method applied to batch mechanical tests of slender rod structure products as a preferred embodiment of the system applied to batch mechanical tests of slender rod structure products.

[0131] According to the system applied to batch mechanical tests of slender rod structure products provided by the present invention, it includes: Module M1: Dynamically adjust the batch quantity according to the production rhythm, adopt a rolling optimization algorithm based on real-time data acquisition, and comprehensively consider the equipment fatigue coefficient and material creep characteristics to determine the maximum test batch; Module M2: Establish a multi-physical field coupling finite element model, adopt a non-linear contact algorithm to simulate the product swing amplitude, iteratively optimize the installation gap through the parameter inversion method, and set the three-dimensional laser scanning to verify that the actual gap and the simulation deviation < 0.5mm; Module M3: Construct a virtual clamping system based on digital twin, use a six-dimensional force sensor to monitor the clamping state in real time, and make the pre-tightening force fluctuation < ±2% through PID closed-loop control, and the surface roughness Ra of the clamping surface ≤ 3.2 μm and the contact area ≥ 85%; Module M4: Develop a modular adaptive fixture system, including a piezoelectric ceramic-driven dynamic damper with a frequency response range of 5Hz - 500Hz; a variable stiffness support arm with a stiffness adjustment ratio ≥ 10:1, and adopt topology optimization design; Module M5: Establish a clamping quality detection system based on machine vision, identify connection defects through a convolutional neural network, use acoustic emission technology to monitor structural damage in real time, and set a dual-redundancy safety interlock mechanism.

[0132] In the module M1, the batch quantity is dynamically adjusted according to the production rhythm, and the formula is: Z = A ÷ (T ÷ t), where t is the time of a single mechanical test, T is the production cycle of the mechanical test, and A is the total quantity of products;

[0133] Introduce a dynamic correction coefficient η, with a range of 0.8 - 1.2, and the calculation formula is optimized to: Z = η × [A ÷ (T / (t + t))], where t is the equipment cooling time and t = 0.1t× , where N is the cumulative number of tests; an infrared thermal imager is set to monitor the temperature rise of the equipment in real time. When T > 15°C, the η value is automatically corrected.

[0134] In the module M2, the multi-physics field coupling finite element modeling process is as follows:

[0135] 1. Model framework construction:

[0136] Structural field: Explicit dynamic equations are used

[0137] Contact field: Define contact pairs

[0138] Thermodynamic field: Couple the temperature field

[0139] In the formula, is the density, is the Cauchy stress tensor, k is the thermal conductivity, is the frictional heat generation power.

[0140] 2. Material constitutive model

[0141] Nonlinear elastoplastic model:

[0142] Temperature-related characteristics (when coupling the thermal field):

[0143] The implementation process of the nonlinear amplitude simulation is as follows:

[0144] 1. Solve the dynamic equation

[0145] Explicit time integration:

[0146] Time step control:

[0147] Load application method:

[0148] Inertial load: Apply the base acceleration

[0149] Forced vibration: Direct nodal force loading

[0150] Convergence control

[0151] Residual control criterion:

[0152] Adaptive time step adjustment: When the number of iterations > 5 times,

[0153] The parameter inversion iterative optimization process is:

[0154] Optimization problem definition, objective function:

[0155]

[0156] is the installation gap involved variable, λ=0.1: Tikhonov regularization coefficient.

[0157] Sensitivity analysis, derivative of adjoint variables:

[0158] The accompanying variable λ satisfies: .

[0159] In the module M3, the fixing state of the clamping device is kept consistent with the actual installation state of the product, including the strength of the clamping device, the preload force of the connection interface and the edge conditions of the product fixation, wherein the resonance point of the clamping device is consistent with the actual state, and the tension force and angle of the soft connection part are consistent with the actual state;

[0160] The specific implementation includes: using swept frequency vibration testing to ensure that the deviation between the first three natural frequencies of the clamping device and the product installation base is <±3%; setting a preload gradient loading system with a loading rate of ≤50N / s, and monitoring the interface stress distribution through a fiber grating sensor array with a spatial resolution of 1cm; establishing an edge condition digital twin database to store ≥100 sets of typical working condition parameter combinations.

[0161] In the module M3, the actual installation state of the slender rod structure product is: one end is fixed with a clamp and rigidly connected to the structural member, and the other end is fixed with a clamp and tightened with three steel wire ropes distributed at 120°. The angle between the steel wire rope and the product is 90°. The above conditions need to be considered in the design of the clamping device, and the tension of the steel wire rope and the material of the clamping device should be consistent with the actual state;

[0162] Building a virtual clamping system based on digital twins includes: developing a bionic clamp with self-sensing function, built-in MEMS accelerometer and strain gauge, using magnetorheological intelligent rope for wire rope tension, adjusting the response time <50ms, setting up a binocular vision system to measure the angle deviation in real time with an accuracy of ±0.1°, and automatically compensating for the thermal expansion coefficient of the material when the temperature fluctuates >±5℃.

[0163] In the module M4, the fixing methods at both ends of the product are inconsistent, one end is rigidly connected, and the other end is non-rigidly connected, and the products are 180° symmetrically distributed; in the product testing phase, the electrical environment of the equipment is tested. If the actual environment does not meet the preset requirements, an electrical environment that meets the preset requirements is created by connecting an isolation transformer to the front end of the product;

[0164] The electrical environment simulation is as follows: a three-degree-of-freedom hydraulic shaker is set at the non-rigid end with a displacement accuracy of ±0.01 mm; an electromagnetic shielding chamber is constructed with a shielding effectiveness of ≥80 dB@10 MHz - 1 GHz; the isolation transformer adopts a double shielding structure with a leakage magnetic flux <1 T; a power quality analyzer is set with THD < 3%; a grounding resistance monitoring device is set with a resistance value < 0.1 Ω.

[0165] Those skilled in the art know that in addition to implementing the systems, devices, and their respective modules provided by the present invention in the form of pure computer-readable program codes, the method steps can be logically programmed to enable the systems, devices, and their respective modules provided by the present invention to be implemented in the form of logic gates, switches, application-specific integrated circuits, programmable logic controllers, and embedded microcontrollers, etc. to achieve the same program. Therefore, the systems, devices, and their respective modules provided by the present invention can be regarded as a kind of hardware component, and the modules included therein for implementing various programs can also be regarded as the structures within the hardware component; the modules for implementing various functions can also be regarded as either software programs for implementing the methods or the structures within the hardware component.

[0166] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A method for mechanical testing of batches of slender rod structure products, characterized in that: include: Step S1: dynamically adjust the batch quantity according to the production rhythm, adopt a rolling optimization algorithm based on real-time data collection, and comprehensively consider the equipment fatigue coefficient and material creep characteristics to determine the maximum test batch; Step S2: Establish a multi-physics field coupling finite element model, use a nonlinear contact algorithm to simulate the product swing, iteratively optimize the installation gap through parameter inversion method, and set up a three-dimensional laser scanning to verify that the deviation between the actual gap and the simulation is less than 0.5mm; Step S3: Build a virtual clamping system based on digital twins, use a six-dimensional force sensor to monitor the clamping state in real time, and use PID closed-loop control to make the preload fluctuation <±2% and the clamping surface roughness Ra≤3.2 m and the contact area ≥ 85%; Step S4: Develop a modular adaptive fixture system, including a piezoelectric ceramic-driven dynamic damper with a frequency response range of 5 Hz-500 Hz; a variable stiffness arm with a stiffness adjustment ratio of ≥10:1, and a topology optimized design; Step S5: Establish a clamping quality inspection system based on machine vision, identify connection defects through convolutional neural networks, use acoustic emission technology to monitor structural damage in real time, and set up a dual redundant safety interlocking mechanism.

2. The method for mechanical testing of a batch of slender rod structure products according to claim 1 is characterized in that: In the step S1, the batch quantity is dynamically adjusted according to the production rhythm, and the formula is: Z=A÷(T÷t), where t is the single mechanical test time, T is the mechanical test production cycle, and A is the total product volume; The dynamic correction coefficient η is introduced, ranging from 0.8 to 1.2, and the calculation formula is optimized as follows: Z = η × [A ÷ (T / (t + t))], where t is the equipment cooling time and t=0.1t× , N is the cumulative number of tests; set the infrared thermal imager to monitor the temperature rise of the equipment in real time. When T>15℃, η value correction is automatically triggered.

3. The method for mechanical testing of a batch of slender rod structure products according to claim 1, characterized in that: In step S3, the fixing state of the clamping device is kept consistent with the actual installation state of the product, including the strength of the clamping device, the preload force of the connection interface and the edge condition of the product fixation, wherein the resonance point of the clamping device is consistent with the actual state, and the tension force and angle of the soft connection part are consistent with the actual state; The specific implementation includes: using swept frequency vibration testing to ensure that the deviation between the first three natural frequencies of the clamping device and the product installation base is <±3%; setting a preload gradient loading system with a loading rate of ≤50N / s, and monitoring the interface stress distribution through a fiber grating sensor array with a spatial resolution of 1cm; establishing an edge condition digital twin database to store ≥100 sets of typical working condition parameter combinations.

4. The method for mechanical testing of a batch of slender rod structure products according to claim 1, characterized in that: In step S3, the actual installation state of the slender rod structure product is: one end is fixed by a clamp and rigidly connected to the structural member, and the other end is fixed by a clamp and tightened and fixed with three steel wire ropes distributed at 120°, the angle between the steel wire rope and the product is 90°, and the tension of the steel wire rope and the material of the clamping device are consistent with the actual state; Building a virtual clamping system based on digital twins includes: developing a bionic clamp with self-sensing function, built-in MEMS accelerometer and strain gauge, using magnetorheological intelligent rope for wire rope tension, adjusting the response time <50ms, setting up a binocular vision system to measure the angle deviation in real time with an accuracy of ±0.1°, and automatically compensating for the thermal expansion coefficient of the material when the temperature fluctuates >±5℃.

5. The method for mechanical testing of a batch of slender rod structure products according to claim 1, characterized in that: In step S4, the fixing methods of the two ends of the product are inconsistent, one end is rigidly connected, and the other end is non-rigidly connected, and the products are 180° symmetrically distributed; in the product testing phase, the electrical environment of the environment in which the equipment is located is tested. If the actual environment does not meet the preset requirements, an electrical environment that meets the preset requirements is created by connecting an isolation transformer to the front end of the product; The electrical environment simulation is as follows: a three-degree-of-freedom hydraulic excitation table is set at the non-rigid end, with a displacement accuracy of ±0.01mm; an electromagnetic shielding room is constructed, with a shielding effectiveness of ≥80dB@10MHz-1GHz; the isolation transformer adopts a double shielding structure, and the leakage flux <1 T; Set the power quality analyzer, THD<3%.

6. A system for mechanical testing of batches of slender rod structure products, characterized in that: include: Module M1: Dynamically adjust the batch quantity according to the production rhythm, adopt a rolling optimization algorithm based on real-time data collection, and comprehensively consider the equipment fatigue coefficient and material creep characteristics to determine the maximum test batch; Module M2: Establish a multi-physics field coupling finite element model, use a nonlinear contact algorithm to simulate the product swing, iteratively optimize the installation gap through parameter inversion method, and set up a three-dimensional laser scan to verify that the deviation between the actual gap and the simulation is less than 0.5mm; Module M3: Build a virtual clamping system based on digital twins, use a six-dimensional force sensor to monitor the clamping state in real time, and use PID closed-loop control to make the preload fluctuation <±2% and the clamping surface roughness Ra≤3.2 m and the contact area ≥ 85%; Module M4: Development of a modular adaptive fixture system, including a piezoelectric ceramic-driven dynamic damper with a frequency response range of 5Hz-500Hz; a variable stiffness arm with a stiffness adjustment ratio of ≥10:1, and a topologically optimized design; Module M5: Establish a clamping quality inspection system based on machine vision, identify connection defects through convolutional neural networks, use acoustic emission technology to monitor structural damage in real time, and set up a dual redundant safety interlock mechanism.

7. The system for mechanical testing of batches of slender rod structure products according to claim 6, characterized in that: In the module M1, the batch quantity is dynamically adjusted according to the production rhythm, and the formula is: Z = A ÷ (T ÷ t), where t is the single mechanical test time, T is the mechanical test production cycle, and A is the total product volume; The dynamic correction coefficient η is introduced, ranging from 0.8 to 1.2, and the calculation formula is optimized as follows: Z = η × [A ÷ (T / (t + t))], where t is the equipment cooling time and t=0.1t× , N is the cumulative number of tests; set the infrared thermal imager to monitor the temperature rise of the equipment in real time. When T>15℃, η value correction is automatically triggered.

8. The system for batch mechanical testing of slender rod structure products according to claim 6, characterized in that: In the module M3, the fixing state of the clamping device is kept consistent with the actual installation state of the product, including the strength of the clamping device, the preload force of the connection interface and the edge conditions of the product fixation, wherein the resonance point of the clamping device is consistent with the actual state, and the tension force and angle of the soft connection part are consistent with the actual state; The specific implementation includes: using swept frequency vibration testing to ensure that the deviation between the first three natural frequencies of the clamping device and the product installation base is <±3%; setting a preload gradient loading system with a loading rate of ≤50N / s, and monitoring the interface stress distribution through a fiber grating sensor array with a spatial resolution of 1cm; establishing an edge condition digital twin database to store ≥100 sets of typical working condition parameter combinations.

9. The system for mechanical testing of slender rod structure products in batches according to claim 6, characterized in that: In the module M3, the actual installation state of the slender rod structure product is: one end is fixed with a clamp and rigidly connected to the structural member, and the other end is fixed with a clamp and tightened with three steel wire ropes distributed at 120°, the angle between the steel wire rope and the product is 90°, and the tension of the steel wire rope and the material of the clamping device are consistent with the actual state; Building a virtual clamping system based on digital twins includes: developing a bionic clamp with self-sensing function, built-in MEMS accelerometer and strain gauge, using magnetorheological intelligent rope for wire rope tension, adjusting the response time <50ms, setting up a binocular vision system to measure the angle deviation in real time with an accuracy of ±0.1°, and automatically compensating for the thermal expansion coefficient of the material when the temperature fluctuates >±5℃.

10. The system for batch mechanical testing of slender rod structure products according to claim 6, characterized in that: In the module M4, the fixing methods at both ends of the product are inconsistent, one end is rigidly connected, and the other end is non-rigidly connected, and the products are 180° symmetrically distributed; in the product testing phase, the electrical environment of the equipment is tested. If the actual environment does not meet the preset requirements, an electrical environment that meets the preset requirements is created by connecting an isolation transformer to the front end of the product; The electrical environment simulation is as follows: a three-degree-of-freedom hydraulic excitation table is set at the non-rigid end, with a displacement accuracy of ±0.01mm; an electromagnetic shielding room is constructed, with a shielding effectiveness of ≥80dB@10MHz-1GHz; the isolation transformer adopts a double shielding structure, and the leakage flux <1 T; Set the power quality analyzer, THD<3%.

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