An indirect measurement method for the blocking force source characteristics of mechanical equipment

Abstract

This invention provides an indirect method for measuring the obstruction force source characteristics of mechanical equipment. The method includes the following steps: S1, obtaining the obstruction force function expression based on vibration transmission path analysis; S2, arranging measuring points on the mechanical equipment assembly system; S3, conducting a mechanical equipment operation test and collecting the responses of the indicated degree of freedom and the verification degree of freedom; S4, conducting a frequency response function test of the assembly system and obtaining typical frequency response function vectors of the verification degree of freedom measuring points and the contact degree of freedom measuring points; S5, calculating the obstruction force vector according to the obstruction force function expression; S6, comparing the predicted vibration response and the actual vibration response at the verification degree of freedom measuring points to verify the accuracy of the obstruction force calculation results. This invention provides an indirect method for measuring the obstruction force source characteristics of mechanical equipment, enabling the measurement of equipment obstruction forces under different installation conditions without disassembling the mechanical equipment.

Description

Technical Field

[0001] This invention relates to the field of mechanical vibration transmission, and more specifically to an indirect method for measuring the characteristics of a blocking force source in mechanical equipment. Background Technology

[0002] In the study of the generation and propagation mechanisms of structural noise in mechanical equipment, it is often necessary to characterize the sound source characteristics of the equipment using quantified characteristic parameters. Ideally, these characteristic parameters should be inherent characteristics of the equipment, unchanging with variations in its installation location and state, and obtainable through simple theoretical or technical means. With the introduction of concepts such as the characteristic power of the source itself and the coupling function of the additional dynamics of the installation structure, two more parameters—free vibration velocity and blocking force—have been introduced to characterize the source characteristics of the equipment, making the source characteristics of the mechanical equipment truly invariant properties of the equipment itself.

[0003] Free vibration velocity is the vibration speed of mechanical equipment in a free state or on a low-impedance foundation; blocking force is the excitation force at the installation interface of mechanical equipment when the vibration velocity is zero. When the equipment is rigidly installed, the excitation force exerted by the feet on the installation foundation can be approximated as the blocking force of the equipment. The two parameters, free vibration velocity and blocking force, are similar to Thevenin's law and Norton's law: compared with the corresponding installation structure impedance, when the source impedance is low, the source can be considered a constant force source; when the source impedance is relatively high, the vibration velocity of the equipment feet is determined by the equipment itself, and the source can be considered a constant velocity source.

[0004] Free vibration velocity, as a physical quantity characterizing the intensity of a sound source, has gained widespread international recognition. However, the development of obstruction force measurement has lagged behind because it is difficult to obtain directly through experiments. Directly measuring obstruction force requires inserting force sensors on all mounting surfaces of the equipment. Furthermore, it faces engineering challenges such as the lack of infinitely stiff bases, force loss at the force sensor mounting points, and difficulty in guaranteeing the assembly accuracy of rigidly mounted equipment. Directly measuring obstruction force is time-consuming and expensive, and its measurement accuracy cannot be guaranteed. Summary of the Invention

[0005] The present invention addresses the shortcomings of the prior art by providing an indirect method for measuring the obstruction force source characteristics of mechanical equipment. This method yields a parameterized expression for the obstruction force, enabling the measurement of the obstruction force under different installation conditions without disassembling the mechanical equipment.

[0006] The technical solution adopted in this invention is: an indirect measurement method for the characteristics of obstructing force sources in mechanical equipment, comprising the following steps:

[0007] S1. Based on vibration transmission path analysis and mechanical equipment source characteristic analysis, a vibration transmission physical model is constructed to obtain the blocking force function expression of the mechanical equipment under different installation conditions;

[0008] S2. The mechanical equipment is mounted on the base by vibration isolators, and measuring points are arranged on the assembly system. The measuring points include contact degree of freedom measuring points, indicating degree of freedom measuring points and verification degree of freedom measuring points. Vibration sensors are installed at each measuring point.

[0009] S3. Conduct mechanical equipment operation tests. When the mechanical equipment is in the specified operating state, collect the vibration response at the indicator degree of freedom measurement point and the verification degree of freedom measurement point.

[0010] S4. Conduct frequency response function tests on the assembly system. Apply excitation to the contact degree of freedom measurement point and measure the response at the indication degree of freedom measurement point and the verification degree of freedom measurement point. Directly obtain the typical frequency response function vectors of the indication degree of freedom measurement point and the contact degree of freedom measurement point, and the typical frequency response function vectors of the verification degree of freedom measurement point and the contact degree of freedom measurement point.

[0011] S5. Based on the typical frequency response function vectors of the indicator degree of freedom measuring point and the contact degree of freedom measuring point obtained in step S4, and the vibration response of the indicator degree of freedom measuring point obtained in step S3, the blocking force vector is calculated.

[0012] S6. Calculate the typical frequency response function vectors of the verification degree of freedom measurement point and the contact degree of freedom measurement point obtained in step S4 to obtain the predicted vibration response at the verification degree of freedom measurement point. Compare it with the actual vibration response collected at the verification degree of freedom measurement point in step S3 to verify the accuracy of the blocking force calculation result.

[0013] According to the above technical solution, in step S1, the formula for calculating the blocking force is as follows:

[0014]

[0015] In the formula: A represents the mechanical equipment, and B represents the mounting base. This is the typical frequency response function vector of the assembly system. for The generalized inverse matrix, The vibration response at measuring point B.

[0016] According to the above technical solution, in step S2, the contact degree of freedom measuring point is set on the contact surface connecting the vibration isolator and the mechanical equipment or base, close to the installation position of the vibration isolator.

[0017] According to the above technical solution, in step S2, the indicator degree of freedom measuring points are set at a position far away from the contact area, and their number is 2-3 times the number of contact degree of freedom measuring points. The indicator degree of freedom measuring points are well spaced and have linear independence.

[0018] According to the above technical solution, in step S2, the verification degree of freedom measurement point is selected at a position that is linearly independent of the indicator degree of freedom measurement point.

[0019] According to the above technical solution, in step S3, before carrying out the mechanical equipment operation test, the mechanical equipment should be shut down, and the background noise of all measuring points should be checked to ensure that the signal-to-noise ratio meets the requirements.

[0020] According to the above technical solution, in step S4, before conducting the frequency response function experiment of the assembly system, the power supply should be cut off, and a hammer should be used to directly strike the contact degree of freedom measuring point in three directions to realize the input of excitation force.

[0021] According to the above technical solution, when excitation cannot be directly applied at the contact point degree of freedom measurement point, the typical frequency response function vector can be indirectly obtained by measuring the reciprocal frequency response function.

[0022] According to the above technical solution, all frequency response function measurements are thoroughly checked for coherence to ensure the validity of the results.

[0023] According to the above technical solution, in step S6, the predicted vibration response at the predicted degree of freedom measurement point and the actual vibration response are plotted on the same coordinate axis using a narrow band spectrum and compared.

[0024] The beneficial effects achieved by this invention are as follows:

[0025] 1. This invention provides an indirect measurement method for the obstruction force source characteristics of mechanical equipment. Through vibration transmission path analysis, a parameterized expression for the obstruction force is obtained, and an indirect measurement method for the obstruction force is further proposed. This method enables the acquisition of the equipment's obstruction force under different installation conditions without disassembling the mechanical equipment. The obtained obstruction force data can be used to simulate and recreate the actual installation state of the equipment, allowing for the evaluation of its vibration state when the equipment is not installed.

[0026] 2. The parametric expression of the blocking force in this invention shows that the blocking force is entirely determined by the mechanical equipment, which can clearly characterize the source characteristics of the structural sound source, is not affected by external installation conditions, and is more conducive to the condition evaluation of the equipment.

[0027] 3. Verification degree-of-freedom measuring points, which are linearly independent of the positions of the indicated degree-of-freedom measuring points, were arranged on the mechanical equipment. By comparing the predicted vibration response at the predicted degree-of-freedom measuring points with the actual vibration response, the scientific validity and accuracy of this method were verified. Attached Figure Description

[0028] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0029] Figure 1 This is a simplified model of vibration transmission in an embodiment of the present invention;

[0030] Figure 2 This is a simplified model for solving interface forces using the inverse matrix in an embodiment of the present invention;

[0031] Figure 3 This is a simplified model of equivalent power transfer in this embodiment of the invention;

[0032] Figure 4 This is a simplified rigid installation model according to an embodiment of the present invention;

[0033] Figure 5 This is a simplified model of flexible installation according to an embodiment of the present invention;

[0034] Figure 6 This is a diagram showing the layout of measuring points according to an embodiment of the present invention;

[0035] Figure 7 This is a line spectrum data diagram of the blocking force in the 1x direction of the machine foot according to an embodiment of the present invention;

[0036] Figure 8 This is a line spectrum data diagram of the blocking force in the 1y direction of the machine foot according to an embodiment of the present invention;

[0037] Figure 9 This is a line spectrum data diagram of the blocking force in the z-direction of the machine foot according to an embodiment of the present invention;

[0038] Figure 10 This is a line spectrum comparing the calculated verification point response and the actual verification point response using the ALJ3460 in this embodiment of the invention.

[0039] Figure 11 This is a line spectrum comparing the calculated verification point response and the actual verification point response using the ALJ3485 in an embodiment of the present invention. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0041] Example 1

[0042] This invention provides an indirect method for measuring the obstruction force source characteristics of mechanical equipment, specifically including the following steps:

[0043] S1. Based on vibration transmission path analysis and mechanical equipment source characteristic analysis, a vibration transmission physical model is constructed to obtain the blocking force function expression of the mechanical equipment under different installation conditions;

[0044] In this embodiment, the complete vibration transmission path includes the vibration source, the path, and the response. The dynamic system containing the operating mechanical equipment is divided into two parts: a substructure A containing active excitation and a passive substructure B containing response nodes. Substructure A is typically represented by the mechanical equipment, and substructure B is typically represented by the mounting base. Figure 1 As shown, a simplified physical model of vibration transmission is constructed. Node 1 represents the excitation point within the system, node 2 represents the simplified contact surface between substructures A and B, and node 3 represents the response point. The two substructures are coupled at node 2. By analyzing substructures A and B separately, the diagonal frequency response function matrix can be constructed as follows:

[0045] (1)

[0046] In formula (1): and These are the responses of substructure A and substructure B, respectively. and These are the responses of substructure A and substructure B at node 2, respectively. The responses are typically acceleration, velocity, and displacement. and These are the interfacial forces at node 2 for substructures A and B, respectively. The excitation force inside the noise source; Let be the frequency response function from node 1 to node 2.

[0047] In this embodiment, as can be seen from equation (1), the interfacial force on substructure B triggers two responses on B. This is the frequency response function of substructure B. During measurement, active device A must be removed, which causes significant inconvenience in practical engineering testing. For example... Figure 2 As shown, a sufficient number of independent response nodes 4 are set at the B end of the substructure. Node 4 is a representation of node 3. The inverse matrix method is used to describe the interfacial forces at all interfaces through node 4. Therefore, the expression for the excitation force at the device interface is obtained as follows:

[0048] (2)

[0049] In this embodiment, as Figure 3As shown, through a set of equivalent forces To characterize the excitation source, the response of the passive receiver can be simulated by shutting down the original source of the system and then applying the equivalent force to assembly AB. The interaction force between assemblies AB can be ignored during the measurement phase. Both the blocking force and the free velocity are source characteristics of the equipment. The equivalent force when the equivalent velocity is zero is the blocking force of the equipment, and the equivalent velocity when the equivalent force is zero is the free velocity of the equipment.

[0050] In this embodiment, as Figure 4 As shown, when the mechanical equipment is rigidly installed, the working excitation of the mechanical equipment is... Can be caused by blocking section load The reaction force is expressed as follows, yielding the system equations for rigid installation:

[0051] (3)

[0052] Due to the interface rigidity, the displacement of node 2 is zero. Further calculation yields the equivalent force calculation formula for rigid installation of mechanical equipment:

[0053] (4)

[0054] In this embodiment, as Figure 5 As shown, in practical engineering, most mechanical equipment is installed in an elastic configuration with vibration isolators. This coupled structure inevitably causes the elastic vibration isolator to exhibit its dynamic characteristics at the interface, and the equivalent force needs to be independent of any connecting part. Therefore, it is assumed that… Given the interface admittance of the test bench including the vibration isolator, we obtain the system equations for elastic mounting:

[0055] (5)

[0056] In equation (5), two boundary conditions, displacement compatibility and force equilibrium, are substituted, i.e. and By combining the equivalent force calculation formula (4), the relationship between the equivalent force and the interface load and interface response parameters can be calculated:

[0057] (6)

[0058] Equation (6) shows that it is not necessary to directly measure the interfacial force; only separate frequency response tests are needed on the admittance of the active substructure and the test bench structure. and These two admittance matrices represent the dynamic stiffness matrices of different components (A, R) configured on the same interface. They can be calculated using simple impedance addition to obtain the following relationship:

[0059] (7)

[0060] Equation (7) shows that the equivalent force result is independent of the dynamics of any other mounting structure to which component R or component A is connected. Converting to admittance notation, the blocking force can be obtained from the inverse admittance calculation of the assembly interface, or by using a sufficient set of indicator points on the passive substructure. express:

[0061] (8)

[0062] Equation (8) shows that the blocking force measurement between the active substructure A and the passive substructure B can be performed directly on the assembly system AB, thereby avoiding the disassembly of any component. The blocking force is only a property of the active substructure A and can be transferred to any passive substructure.

[0063] S2. The mechanical equipment is mounted on the base by vibration isolators. Measuring points are arranged on the assembly system. The measuring points include contact degree of freedom measuring points, indicating degree of freedom measuring points and verification degree of freedom measuring points. Vibration sensors are installed at each measuring point.

[0064] In this embodiment, the mechanical equipment has four feet and is mounted on a base via vibration isolators. Measurement points are arranged for this mechanical equipment. Based on the node classification in the vibration transmission physical model, the measurement points in the experiment can be divided into contact degree-of-freedom (DOF) measurement points, indicator degree-of-freedom (ADOF) measurement points, and verification degree-of-freedom (CAP) measurement points. Contact degree-of-freedom (ADOF) measurement points should be selected as close as possible to the vibration isolator mounting location and fixed on the contact surface connecting the vibration isolator to the mechanical equipment or base, generally near the fastening bolts. Indicator degree-of-freedom (ADOF) measurement points are set away from the contact area, and their number is set to 2-3 times the number of contact degree-of-freedom (ADOF) measurement points, making the entire system "statically indeterminate." The response of the indicator degree-of-freedom (ADOF) measurement points should be as linearly independent as possible; therefore, well-spaced locations and different directions are chosen when selecting the measurement points. CAPF measurement points are used to verify the data quality of the blocking force obtained by this method. CAPF measurement points should not be arranged in the contact area or the area where the indicator degree-of-freedom (ADOF) measurement points are located. CAPF measurement points should be in different locations or directions from any indicator degree-of-freedom (ADOF) measurement points to ensure linear independence.

[0065] In this embodiment, the measuring points are arranged as follows: Figure 6 As shown, a test bench will be built using a type of fan, and two types of vibration isolators, ALG3460 and ALG3485, will be used. The fan equipment will be elastically mounted on the equipment base using vibration isolators at four feet. The four feet of the fan are designated as the contact points of the assembly system, i.e., nodes 2. Each contact point has 3 degrees of freedom, resulting in 12 degrees of freedom for the obstruction force of the equipment to be determined, which can be represented by a complex matrix as follows:

[0066]

[0067] In this embodiment, the indicated degrees of freedom are arranged at the mounting interfaces as much as possible to improve the test quality of the assembly system admittance matrix. The indicated degrees of freedom are selected at the mounting bolts of the foot isolators, near the base isolators, and on the base structure. Specifically: a triaxial acceleration sensor is arranged approximately 1 cm away from the mounting bolts of the foot isolators on each of the four foot isolators; a triaxial acceleration sensor is arranged approximately 1 cm away from the base side of each of the four isolators; and four triaxial acceleration sensors (points 5, 7, 8, and 9) are staggered at positions on the base structure close to the contact surface. Thus, the test bench has a total of 12 triaxial acceleration measurement points, including the contact degree of freedom, for a total of 36 degrees of freedom. The component of the blocking force to be determined has 12 degrees of freedom, so the number and location of the measurement points meet the relevant requirements.

[0068] In this embodiment, a vibration accelerometer is placed at measuring point 6z as a verification degree of freedom to measure the difference between the response value obtained from the calculated blocking force and the actual measured response value. Measuring point 6z is located far from the contact surface, maintaining maximum possible linearity independence from the indicating degree of freedom measuring point. A vibration accelerometer is placed at measuring point 6x as a phase reference measuring point. Since the self-power spectrum of the response point on the indicating degree of freedom loses phase information, a phase reference signal is introduced to incorporate phase information into all signals for matrix operations.

[0069] S3. Conduct mechanical equipment operation tests. When the mechanical equipment is in the specified operating state, collect the vibration response at the indicator degree of freedom measurement point and the verification degree of freedom measurement point.

[0070] In this embodiment, before conducting the mechanical equipment operation test, the mechanical equipment should be turned off, and the background noise of all measuring points should be checked to ensure that the signal-to-noise ratio meets the requirements.

[0071] In this embodiment, after all measuring points are arranged, the fan is started to obtain the indicating degree of freedom. Verify degrees of freedom The vibration acceleration data at the phase reference degree of freedom measurement point were also obtained. The acceleration line spectra of the verification degree of freedom and the acceleration line spectra of the indication degree of freedom, containing phase information, were calculated. In this experiment, the verification degree of freedom... The quantity is 1; the verification degrees of freedom include 36 degrees of freedom from the measuring points at the equipment feet, the measuring points near the base vibration isolator, and the measuring points at the base structure, which are represented by the matrix as follows:

[0072]

[0073] S4. Conduct frequency response function tests on the assembly system. Apply excitation to the contact degree of freedom measurement point and measure the response at the indication degree of freedom measurement point and the verification degree of freedom measurement point. Directly obtain the typical frequency response function vectors of the indication degree of freedom measurement point and the contact degree of freedom measurement point, and the typical frequency response function vectors of the verification degree of freedom measurement point and the contact degree of freedom measurement point.

[0074] In this embodiment, the power supply should be cut off before conducting the frequency response function experiment of the assembly system. A force hammer should be used to directly strike the contact degree of freedom measuring point in three directions to realize the input of excitation force.

[0075] In this embodiment, the frequency response function is for the entire assembly system; the fan does not need to be dismantled. Based on the obstruction force component to be determined, it is known that hammer tests need to be performed on the equipment's four mounting feet in a total of 12 directions to obtain the system's frequency response function. This yields the frequency response function from the contact degrees of freedom to the indicated degrees of freedom. and the frequency response function from contact degree of freedom to verification degree of freedom. as follows:

[0076]

[0077]

[0078] In this embodiment, all frequency response function measurements are subjected to a thorough coherence check to ensure the validity of the results.

[0079] S5. Based on the typical frequency response function vectors of the indicator degree of freedom measuring point and the contact degree of freedom measuring point obtained in step S4, and the vibration response of the indicator degree of freedom measuring point obtained in step S3, the blocking force vector is calculated.

[0080] In this embodiment, Figures 7-9 The figures show the line spectrum data of the blocking force of foot 1 in the x, y and z directions. As can be seen from the figures, the line spectrum data, whether at the characteristic line spectrum or the 10Hz-150Hz wideband line spectrum, has a good fit at its characteristic frequency, which to a certain extent verifies the consistency of the blocking force of the equipment source characteristics under different installation conditions.

[0081] S6. Calculate the typical frequency response function vectors of the verification degree of freedom measurement point and the contact degree of freedom measurement point obtained in step S4 to obtain the predicted vibration response at the verification degree of freedom measurement point. Compare it with the actual vibration response collected at the verification degree of freedom measurement point in step S3 to verify the accuracy of the blocking force calculation result.

[0082] In this embodiment, the fan is installed on two types of vibration isolators. The measurement data of the blocking force component at the machine foot 1 at the characteristic frequency of 25Hz and its error are shown in Table 1. The deviation values ​​are all less than 3dB.

[0083] Table 1

[0084]

[0085] In this embodiment, the predicted vibration response and the actual vibration response at the predicted degree of freedom measurement point are plotted in narrowband on the same coordinate axis and compared. Simultaneously, the line spectrum curves of the calculated verification point response and the actual verification point response under a single test are compared to verify the validity of the data quality for this indirect measurement of obstruction force. Relevant data are as follows: Figure 10 and Figure 11 As shown in Table 2, the vibration acceleration data of the two methods at the characteristic line spectra of 25Hz and 50Hz, and the total vibration acceleration data of 10Hz-150Hz are compared. The comparison results show that the error in solving the obstruction force at the verification degree of freedom measurement point is small, proving that the obstruction force measurement accuracy of this application is good.

[0086] Table 2

[0087]

[0088] Example 2

[0089] The principle and technical solution of Example 2 are basically the same as those of Example 1. The difference is that in actual engineering, when conducting frequency response function tests on assembly systems, there is sometimes not enough space to apply force hammer excitation to the contact degree of freedom measurement point. In this case, the typical frequency response function vector can be indirectly obtained by measuring the reciprocal frequency response function.

[0090] In this embodiment, when selecting the location of the indicator degree of freedom measuring point, it should be considered whether the selected location is easy to excite the degree of freedom. If the contact degree of freedom measuring point cannot be excited by a force hammer, a reciprocal frequency response function measurement is carried out. By applying excitation to the indicator degree of freedom measuring point, the frequency response function matrix of the contact degree of freedom measuring point is obtained, and then the typical frequency response function vectors of the indicator degree of freedom measuring point and the contact degree of freedom measuring point are calculated. Finally, the blocking force vector is calculated.

[0091] The embodiments described above are some, but not all, of the embodiments of this application. The detailed description of the embodiments of this application is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application.

Claims

1. An indirect method for measuring the characteristics of a blocking force source in mechanical equipment, characterized in that: Includes the following steps: S1. Based on vibration transmission path analysis and mechanical equipment source characteristic analysis, a vibration transmission physical model is constructed to obtain the blocking force function expression of the mechanical equipment under different installation conditions; S2. The mechanical equipment is mounted on a base using vibration isolators. Measuring points are arranged on the assembly system, including contact degree-of-freedom measuring points, indicating degree-of-freedom measuring points, and verification degree-of-freedom measuring points. Vibration sensors are installed at each measuring point. The indicating degree-of-freedom measuring points are located far from the contact area, and their number is 2-3 times that of the contact degree-of-freedom measuring points. The indicating degree-of-freedom measuring points are well-spaced and linearly independent. The verification degree-of-freedom measuring points are selected at locations that are linearly independent of the indicating degree-of-freedom measuring points. S3. Conduct mechanical equipment operation tests. When the mechanical equipment is in the specified operating state, collect the vibration response at the indicator degree of freedom measurement point and the verification degree of freedom measurement point. S4. Conduct frequency response function tests on the assembly system. Apply excitation to the contact degree of freedom measurement point and measure the response at the indication degree of freedom measurement point and the verification degree of freedom measurement point. Directly obtain the typical frequency response function vectors of the indication degree of freedom measurement point and the contact degree of freedom measurement point, and the typical frequency response function vectors of the verification degree of freedom measurement point and the contact degree of freedom measurement point. S5. Based on the typical frequency response function vectors of the indicator degree of freedom measuring point and the contact degree of freedom measuring point obtained in step S4, and the vibration response of the indicator degree of freedom measuring point obtained in step S3, the blocking force vector is calculated. S6. Calculate the typical frequency response function vectors of the verification degree of freedom measurement point and the contact degree of freedom measurement point obtained in step S4 to obtain the predicted vibration response at the verification degree of freedom measurement point. Compare it with the actual vibration response collected at the verification degree of freedom measurement point in step S3 to verify the accuracy of the blocking force calculation result.

2. The indirect measurement method for the blocking force source characteristics of mechanical equipment according to claim 1, characterized in that: In step S1, the formula for calculating the blocking force is as follows: In the formula: A represents the mechanical equipment, and B represents the mounting base. This is the typical frequency response function vector of the assembly system. for The generalized inverse matrix, The vibration response at measuring point B.

3. The indirect measurement method for the obstruction force source characteristics of mechanical equipment according to claim 1, characterized in that: In step S2, the contact degree of freedom measuring point is set on the contact surface where the vibration isolator connects to the mechanical equipment or base, close to the installation position of the vibration isolator.

4. The indirect measurement method for the blocking force source characteristics of mechanical equipment according to claim 1, characterized in that: In step S3, before conducting the mechanical equipment operation test, the mechanical equipment should be shut down, and the background noise of all measuring points should be checked to ensure that the signal-to-noise ratio meets the requirements.

5. The indirect measurement method for the blocking force source characteristics of mechanical equipment according to claim 1, characterized in that: In step S4, before conducting the frequency response function experiment of the assembly system, the power supply should be cut off, and a force hammer should be used to directly strike the contact degree of freedom measuring point in three directions to realize the input of excitation force.

6. The indirect measurement method for the blocking force source characteristics of mechanical equipment according to claim 5, characterized in that: When excitation cannot be directly applied at the contact point measurement point, the typical frequency response function vector can be indirectly obtained by measuring the reciprocal frequency response function.

7. The indirect measurement method for the obstruction force source characteristics of mechanical equipment according to claim 1, characterized in that: All frequency response function measurements are thoroughly coherently checked to ensure the validity of the results.

8. The indirect measurement method for the blocking force source characteristics of mechanical equipment according to claim 1, characterized in that: In step S6, the predicted vibration response and the actual vibration response at the predicted degree of freedom measurement point are plotted on the same coordinate axis using narrowband spectra and compared.

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