Split dynamic force measurement platform and method of use

Abstract

The application provides a kind of split load dynamic force measuring platform and use method, through the installation of split load column, enough large installation surface and load capacity can be provided for large mass and large volume vibration source;At the same time, frequency domain data is used during calibration, and an analog piece with the same mass as the real vibration source is introduced, considering the influence of the fundamental frequency of the measuring platform and the mass of the real vibration source on the measurement results;The installation of one-way acceleration sensor and one-way force compensation sensor compensates the interference of inertia force and environmental noise of the measuring platform on the measurement results, improves the accuracy of calibration and measurement, and provides more convincing measurement data for evaluating the influence of real vibration source dynamic disturbance force on precision equipment.

Description

Technical Field

[0001] This invention relates to the field of dynamic force measurement, specifically providing a split-load dynamic force measurement platform and its usage method that takes into account inertial force, vibration source mass, and environmental noise. Background Technology

[0002] Dynamic disturbance forces generated by moving parts on precision instruments such as space telescopes and lithography machines can significantly interfere with their performance and even damage their precision components. Therefore, ground-based measurements to assess the impact of dynamic disturbance forces on equipment in real-world environments are crucial. Furthermore, moving parts on precision instruments (such as the survey module in a space telescope) are becoming increasingly larger and heavier, necessitating a ground-based dynamic force measurement device. This device requires sufficient support and mounting surface. Since vibration sources of different masses result in different fundamental frequencies for the overall system, the influence of the moving part's mass on the measurement device's fundamental frequency must be considered. However, to meet these design requirements, the size and mass of the measurement platform inevitably increase. During dynamic force measurements, the platform's inertial force and its fundamental frequency can introduce significant errors to the measurement results. Moreover, although the size of moving parts in some precision instruments is constantly increasing, the amplitude of their dynamic disturbance forces is very small, approaching ambient noise. Therefore, higher requirements are placed on the measurement equipment, its calibration, and its use.

[0003] Currently, most measurement platforms are calibrated based on static calibration. Even platforms used in dynamic measurements are calibrated statically, which introduces the platform's fundamental frequency, causing significant errors in the measurement. The current calibration process does not consider the influence of the vibration source mass on the overall system fundamental frequency. Existing technologies include some dynamic force measurement devices with large mounting surfaces and load capacities, such as Chinese patents CN109990888B and CN111928988B, but these do not consider the influence of platform inertial forces and environmental noise. This introduces errors during the measurement process and reduces measurement accuracy.

[0004] Therefore, there is an urgent need to design a dynamic force measurement platform that can not only provide a large mounting surface and load capacity, but also take into account the interference of vibration source mass, platform inertial force, fundamental frequency and environmental noise during calibration and measurement, thereby improving the accuracy of measurement. Summary of the Invention

[0005] To address the aforementioned problems, this invention provides a split-load dynamic force measurement platform and its usage method that considers inertial force, vibration source mass, and environmental noise. While ensuring that the measuring equipment can provide a sufficiently large mounting surface and load capacity, it compensates for errors caused by equipment inertial force and environmental interference, and considers the influence of vibration source mass and platform fundamental frequency, thereby improving the measurement accuracy of the equipment.

[0006] The split-load dynamic force measurement platform provided by this invention includes:

[0007] The load-bearing column is positioned between the upper and lower mounting plates and is located in the center.

[0008] Four unidirectional force measurement sensors are evenly arranged between the upper and lower mounting plates, and the unidirectional force measurement sensors are installed in parallel with the load-bearing column;

[0009] Four unidirectional force compensation sensors are evenly arranged on the upper surface of the lower mounting plate and do not contact the upper mounting plate.

[0010] Four unidirectional acceleration sensors are evenly distributed on the lower surface of the upper mounting plate and do not contact the lower mounting plate.

[0011] Preferably, the upper mounting plate is provided with four bosses for connecting unidirectional force measurement sensors and one boss for connecting the load-bearing column.

[0012] Preferably, the lower mounting plate is provided with four bosses for connecting unidirectional force measurement sensors, four bosses for connecting unidirectional force compensation sensors, and one boss for connecting the load-bearing column.

[0013] Preferably, the lower mounting plate has countersunk holes, and the lower mounting plate is connected to the vibration isolation table by screws.

[0014] A method for using a split-load dynamic force measurement platform includes the following steps:

[0015] S1. Calibration of the split-load dynamic force measurement platform, the specific steps are as follows:

[0016] S11. Connect the lower mounting plate of the split-load dynamic force measurement platform to the vibration isolation platform, and connect the simulation plate with the same mass as the real vibration source to the upper mounting plate.

[0017] S12. Connect the outputs of the unidirectional force measurement sensor, the unidirectional force compensation sensor, and the unidirectional acceleration sensor to the signal amplifier and the data acquisition in sequence, and set the reference sampling frequency and the reference sampling time.

[0018] S13. Obtain the moment of inertia matrix J and mass of the split-load dynamic force measurement platform;

[0019] S14. Input the known calibration force into the analog chip, use data acquisition to collect the known calibration force, the output of the unidirectional force measurement sensor and the output of the unidirectional acceleration sensor, and calculate the calibration matrix.

[0020] S2. Dynamic force measurement of real vibration sources:

[0021] S21. Remove the simulation plate and connect the real vibration source to the upper mounting plate;

[0022] S22. The real vibration source starts working, and the outputs of the unidirectional force measurement sensor, unidirectional force compensation sensor, and unidirectional acceleration sensor are collected according to the reference sampling frequency and reference sampling time; based on the calibration matrix and the outputs of the unidirectional force measurement sensor and unidirectional acceleration sensor, the three-dimensional force F of the disturbance without considering noise is obtained. m (ω);

[0023] S23. Calculate the environmental interference F based on the output of the unidirectional force compensation sensor. env (ω);

[0024] S24. Obtain the true three-dimensional force F according to the following formula. real (ω):

[0025] F real (ω)=F m (ω)-F env (ω).

[0026] Preferably, the rotational inertia matrix and mass of the split-load dynamic force measurement platform are obtained through CAD simulation or experiment.

[0027] Preferably, the specific process of S14 is as follows: Three different known calibration forces are input to the analog chip, and the known three-dimensional force matrix F is formed by collecting the calibration forces from the three inputs. c (ω) is as follows:

[0028]

[0029] Among them, F zi-c (ω) represents the input force collected at the i-th time, M xi-c (ω) represents the input torque in the X direction acquired at the i-th time, M yi-c (ω) represents the input torque in the Y direction collected for the i-th time, where i = 1, 2 or 3;

[0030] The outputs of the four unidirectional force measurement sensors form an output voltage matrix U. c (ω) is as follows:

[0031]

[0032] Among them, [U 1i-c (ω)U 2i-c (ω)U 3i-c (ω)U 4i-c (ω)] T This represents the voltage collected from the four unidirectional force measurement sensors 4 in the i-th iteration;

[0033] The inertial force F of the upper mounting plate is calculated using the outputs of four unidirectional accelerometers. mass-c (ω) is as follows:

[0034]

[0035]

[0036] Among them, F zi-mass-c (ω) represents the inertial force of the upper mounting plate in the Z direction when the calibration force is input for the i-th time; M xi-mass-c (ω) represents the moment of inertia of the upper mounting plate in the X direction when the calibration force is input for the i-th time; M yi-mass-c (ω) represents the moment of inertia of the upper mounting plate in the Y direction when the calibration force is input for the i-th time; m represents the mass of the upper mounting plate, a zi (ω) represents the acceleration of the upper mounting plate in the Z direction, a xi (ω) represents the acceleration of the upper mounting plate in the X direction, a yi (ω) represents the acceleration of the upper mounting plate in the Y direction, a ki (ω) represents the output acceleration from the k-th unidirectional accelerometer when the i-th calibration force is input, where k = 1, 2, 3 or 4, and l1 represents the distance between two adjacent unidirectional accelerometers;

[0037] The calibration matrix G(ω) is calculated as follows:

[0038] G(ω)=[F c (ω)-F mass-c (ω)]U c (ω) T [U c (ω)U c (ω) T ] -1 .

[0039] Preferably, the three-dimensional force F that does not consider noise disturbance m The formula for calculating (ω) is as follows:

[0040] F m (ω) 3×1 =G(ω) 3×4 U m (ω) 4×1 +F mass-m (ω) 3×1 ;

[0041] Among them, U m (ω) represents the measured voltage matrix of the four unidirectional force sensors when measuring a real vibration source; F mass-m (ω) represents the inertial force of the upper mounting plate calculated based on the outputs of four unidirectional acceleration sensors when measuring the actual vibration source.

[0042] Preferred, true three-dimensional force F realThe formula for calculating (ω) is as follows:

[0043]

[0044]

[0045] Among them, F j (ω) represents the output force of the j-th unidirectional force compensation sensor when measuring a real vibration source, where j = 1, 2, 3 or 4, and l2 represents the distance between two adjacent unidirectional force compensation sensors.

[0046] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0047] This invention provides a sufficiently large mounting surface and load capacity for large-mass, large-volume vibration sources. Furthermore, it addresses the impact of the fundamental frequency of the measurement platform and the mass of the vibration source on the measurement results during the vibration source disturbance force measurement process. It minimizes the interference of platform inertial force and environmental noise on the measurement results, improves the accuracy of calibration and actual measurement, and enables more effective evaluation of the impact of the dynamic disturbance force of the vibration source on precision equipment on the ground. Attached Figure Description

[0048] Figure 1 This is a structural schematic diagram of the split-load dynamic force measurement platform provided according to an embodiment of the present invention;

[0049] Figure 2 This is an exploded view of a split-load dynamic force measurement platform provided according to an embodiment of the present invention.

[0050] Figure 3 This is a schematic diagram of the lower surface structure of the upper mounting plate according to an embodiment of the present invention;

[0051] Figure 4 This is a schematic diagram of the upper surface structure of the lower mounting plate according to an embodiment of the present invention;

[0052] Figure 5 This is an assembly diagram of the load-bearing dynamic force measurement platform provided in the calibration process according to an embodiment of the present invention;

[0053] Figure 6 This is a calibration flowchart of the split-load dynamic force measurement platform provided according to an embodiment of the present invention;

[0054] Figure 7 This is the measurement flow of the split-load dynamic force measurement platform provided according to an embodiment of the present invention.

[0055] Process diagram.

[0056] The reference numerals in the figures include:

[0057] Upper mounting plate 1, first boss 11, second boss 12, mounting groove 13, lower mounting plate 2, countersunk hole 21, third boss 22, fourth boss 23, fifth boss 24, load-bearing column 3, unidirectional force measurement sensor 4, unidirectional first force measurement sensor 41, second force measurement sensor 42, third force measurement sensor 43, fourth force measurement sensor 44, unidirectional force compensation sensor 5, first unidirectional force compensation sensor 51, second unidirectional force compensation sensor 52, third unidirectional force compensation sensor 53, fourth unidirectional force compensation sensor 54, unidirectional acceleration sensor 6, first unidirectional acceleration sensor 61, second unidirectional acceleration sensor 62, third unidirectional acceleration sensor 63, fourth unidirectional acceleration sensor 64, analog plate 7. Detailed Implementation

[0058] In the following description, embodiments of the invention will be described with reference to the accompanying drawings. In the description below, the same modules are denoted by the same reference numerals. Where the same reference numerals are used, their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0059] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not constitute a limitation thereof.

[0060] Figure 1 The structure of a split-load dynamic force measurement platform provided according to an embodiment of the present invention is shown.

[0061] like Figure 1 As shown, this invention provides a distributed dynamic force measurement platform, which can effectively reduce the influence of inertial force, vibration source mass, and environmental noise on the measurement results. Its structure includes: an upper mounting plate 1, a lower mounting plate 2, a distributed column 3, a unidirectional force measurement sensor 4, a unidirectional force compensation sensor 5, and a unidirectional acceleration sensor 6, wherein:

[0062] Figure 2 The structural composition of the split-load dynamic force measurement platform provided according to an embodiment of the present invention is shown.

[0063] like Figure 2 As shown, the unidirectional force measurement sensor 4 is used to measure the force and torque on the split-load dynamic force measurement platform. Specifically, it includes: a first unidirectional force measurement sensor 41, a second force measurement sensor 42, a third force measurement sensor 43, and a fourth force measurement sensor 44 of the same model. The four unidirectional force measurement sensors 4 are evenly distributed in a square between the upper mounting plate 1 and the lower mounting plate 2.

[0064] The unidirectional force compensation sensor 5 is used to compensate for interference forces and torques from the environment, thereby improving the measurement accuracy. Specifically, it includes a first unidirectional force compensation sensor 51, a second unidirectional force compensation sensor 52, a third unidirectional force compensation sensor 53, and a fourth unidirectional force compensation sensor 54 of the same model. The four unidirectional force compensation sensors 5 are evenly distributed in a square between the upper mounting plate 1 and the lower mounting plate 2, and the distance between any two adjacent unidirectional force compensation sensors 5 is l2.

[0065] The unidirectional acceleration sensor 6 is used to measure the acceleration and angular acceleration of the upper mounting plate 1. Specifically, it includes a first unidirectional acceleration sensor 61, a second unidirectional acceleration sensor 62, a third unidirectional acceleration sensor 63, and a fourth unidirectional acceleration sensor 64 of the same model. The four unidirectional acceleration sensors 6 are evenly distributed in a square on the bottom surface of the upper mounting plate 1, and the distance between any two adjacent unidirectional acceleration sensors 6 is l1.

[0066] Figure 3 The lower surface structure of the upper mounting plate provided according to an embodiment of the present invention is shown.

[0067] Figure 4 The upper surface structure of the lower mounting plate provided according to an embodiment of the present invention is shown.

[0068] like Figure 3 and Figure 4As shown, the lower surface of the upper mounting plate 1 is provided with four first protrusions 11, which are evenly distributed at the four corners of the upper mounting plate 1. The first protrusions 11 are used to connect with the unidirectional force measurement sensor 4. The design of the protrusions reduces the flatness requirements of the upper mounting plate 1, thereby reducing processing energy and cost. Correspondingly, the upper surface of the lower mounting plate 2 is also provided with four third protrusions 22, which correspond one-to-one with the positions of the first protrusions 11 and are also used to connect with the unidirectional force measurement sensor 4. The central area of ​​the lower surface of the upper mounting plate 1 is a square groove, and a large second protrusion 12 is provided at the center of the square groove. The upper surface of the lower mounting plate 2 is also provided with a fifth protrusion 24. The load-sharing column 3 is connected between the upper mounting plate 1 and the lower mounting plate 2 through the second protrusion 12 and the fifth protrusion 24. The design of the load-sharing column 3 improves the load capacity and fundamental frequency of the load-sharing dynamic force measurement platform. Four mounting slots 13 are formed at the four corners of the square recess for mounting and positioning the unidirectional acceleration sensor 6. The unidirectional acceleration sensor 6 is installed in the mounting slots 13 and has no contact with the lower mounting plate 2, so there is no interaction force. Threaded holes are formed on the upper surface of the upper mounting plate 1 for fixing the vibration source. Four fourth bosses 23 are also provided on the upper surface of the lower mounting plate 2. The fourth bosses 23 are used to connect the unidirectional force compensation sensor 5. The unidirectional force compensation sensor 5 has no contact with the upper mounting plate 1 and there is no interaction force. Multiple countersunk holes 21 are evenly formed on the lower mounting plate 2. The lower mounting plate 2 can be fixed to the vibration isolation platform by screws passing through the countersunk holes 21.

[0069] The present invention provides a dynamic three-dimensional force measurement platform, on which a six-dimensional force measurement platform can be built.

[0070] The method of using the split-load dynamic force measurement platform provided in this embodiment of the invention includes the following steps:

[0071] Figure 6 The calibration process of the split-load dynamic force measurement platform provided according to an embodiment of the present invention is shown.

[0072] like Figure 6 As shown in Figure S1, since the load-sharing dynamic force measurement platform proposed in this invention is designed with load-sharing columns 3, the force and torque measured by the unidirectional force measurement sensor 4 are not equal to the force and torque experienced by the measurement platform. Therefore, it is necessary to calibrate the platform before performing dynamic force measurement. The calibration steps for the load-sharing dynamic force measurement platform are as follows:

[0073] S11. Since environmental interference cannot be unified between the calibration and measurement processes, the calibration process is carried out in a low-interference or interference-free environment, such as late at night or in an environment with extremely weak environmental noise interference. To avoid the influence of the fundamental frequency of the split-load dynamic force measurement platform on the measurement results, the dynamic calibration of this invention is based on frequency domain data. Simulation experiments show that the fundamental frequency of the overall system is different when different mass vibration sources are added to the split-load dynamic force measurement platform. Therefore, to avoid the influence of the vibration source on the fundamental frequency of the overall system during the calibration process, this invention uses a simulation chip 7 with the same mass as the real vibration source as a virtual vibration source in the calibration process.

[0074] Figure 5 The assembly of the split-load dynamic force measurement platform during the calibration process provided by an embodiment of the present invention is shown.

[0075] like Figure 5 As shown, to accommodate vibration sources of different masses, the simulation plate 7 uses plates of different masses. Different combinations of these plates are possible, ensuring that the final simulation plate 7 has the same mass as the actual vibration source. It is then mounted on the upper surface of the upper mounting plate 1 using screws. The lower mounting plate 2 of the split-load dynamic force measurement platform is connected to the vibration isolation platform, and the simulation plate 7, with the same mass as the actual vibration source, is connected to the upper mounting plate 1.

[0076] S12. Connect the outputs of the unidirectional force measurement sensor 4, the unidirectional force compensation sensor 5, and the unidirectional acceleration sensor 6 to the signal amplifier and data acquisition in sequence, and set the sensitivity coefficients of the unidirectional force compensation sensor 5 and the unidirectional acceleration sensor 6. Acquire the outputs of each sensor through data acquisition, and save the output data using a computer. When acquiring the output, you can set an appropriate sampling frequency and sampling time based on experience as the reference sampling frequency and reference sampling time. For example, the reference sampling frequency is 2048Hz and the reference sampling time is 16s.

[0077] S13. Obtain the rotational inertia matrix J and mass of the split-load dynamic force measurement platform through simulation calculation using CAD software or through actual experiments.

[0078] S14. Different known calibration forces are input into the simulation chip 7 three times through the calibration mechanism. The input calibration forces should include the required three-dimensional spatial force and torque. The calibration mechanism and how to implement the force input are existing technologies and will not be described in detail here. During the three calibration force input processes, the outputs of the calibration force, the four unidirectional force measurement sensors 4, and the four unidirectional acceleration sensors 6 are collected by data acquisition.

[0079] During the three calibration force input processes, the collected calibration forces form a known three-dimensional force matrix F. c (ω) is as follows:

[0080]

[0081] Among them, F zi-c (ω) represents the input force collected at the i-th time, M xi-c (ω) represents the input torque in the X direction acquired at the i-th time, M yi-c (ω) represents the input torque in the Y direction of the i-th acquisition, where i = 1, 2 or 3, and the subscript c is an abbreviation for calibration.

[0082] During the three calibration force input processes, the outputs of the four unidirectional force measurement sensors 4 are collected to form an output voltage matrix U. c (ω) is as follows:

[0083]

[0084] Among them, [U 1i-c (ω)U 2i-c (ω)U 3i-c (ω)U 4i-c (ω)] T This represents the voltage obtained from the four unidirectional force measurement sensors 4 in the i-th measurement. T Represents the transpose of a matrix, specifically, U 1i-c (ω) represents the voltage and U from the unidirectional force measurement sensor 41. 2i-c (ω) represents the voltage and U from the unidirectional force measurement sensor 42. 3i-c (ω) represents the voltage and U from the unidirectional force measurement sensor 43. 4i-c (ω) represents the voltage from the unidirectional force measurement sensor 44.

[0085] During the three calibration force input processes, the inertial force F of the upper mounting plate is calculated using the outputs of four unidirectional acceleration sensors 6. mass-c (ω), for ease of engineering application, the inertial force F of the upper mounting plate 1 is measured by multiplying the inertial mass matrix J of the upper mounting plate 1 by the acceleration matrix of the upper mounting plate 1. mass-c (ω), the formula for calculation is as follows:

[0086]

[0087] Wherein, vector [a zi (ω)α xi (ω)α yi (ω)] T The calculation for (i = 1, 2, or 3) is as follows:

[0088]

[0089] Among them, F zi-mass-c(ω) represents the inertial force of the upper mounting plate in the Z direction when the calibration force is input for the i-th time, through the acceleration a of the upper mounting plate 1 in the Z direction. zi (ω) is obtained by multiplying the mass m of mounting plate 1 above; M xi-mass-c (ω) represents the inertial torque of the upper mounting plate 1 in the X direction when the calibration force is input for the i-th time. It is obtained by multiplying the angular acceleration by the moment of inertia J, which can be obtained experimentally or from CAD software; M yi-mass-c (ω) represents the moment of inertia of the upper mounting plate 1 in the Y direction when the calibration force is input for the i-th time, M yi-mass-c (ω) and M xi-mass-c (ω) is calculated in the same way; m represents the mass of the upper mounting plate 1, a zi (ω) represents the acceleration of the upper mounting plate 1 in the Z direction, a xi (ω) represents the acceleration of the upper mounting plate 1 in the X direction, a yi (ω) represents the acceleration of the upper mounting plate 1 in the Y direction, a ki (ω) represents the output acceleration from the k-th (k = 1, 2, 3 or 4) unidirectional accelerometer 6 when the i-th input calibration force is applied, and l1 represents the distance between two adjacent unidirectional accelerometer 6.

[0090] Without considering environmental noise, the inertial force of the upper mounting plate 1, and the vibration source mass and system fundamental frequency, the dynamic calibration equation of the platform is calculated as follows:

[0091] F c (ω) 3×3 =G(ω) 3×4 U c (ω) 4×3 +F mass-c (ω) 3×3 ;

[0092] Based on the method for solving the pseudo-inverse matrix, the calculation formula of the above dynamic calibration equation is transformed into the calibration matrix G(ω) as follows:

[0093] G(ω)=[F c (ω)-F mass-c (ω)]U c (ω) T [U c (ω)U c (ω) T ] -1 .

[0094] Figure 7 The measurement process of the load-bearing dynamic force measurement platform provided according to an embodiment of the present invention is shown.

[0095] like Figure 7As shown, after the calibration of S2 and the split-load dynamic force measurement platform is completed, dynamic force measurement of the actual vibration source can be performed. The specific steps are as follows:

[0096] S21. Connect the lower mounting plate 2 of the split-load dynamic force measurement platform to the vibration isolation platform, remove the simulation plate 7, and connect the real vibration source to the upper mounting plate 1. Since the measurement will take into account the interference of environmental noise, that is, the environmental interference force is obtained by the unidirectional force compensation sensor 5 to compensate for the final result, there is no need to make requirements on the measurement environment and time, and the measurement can be carried out in an environment with large noise interference.

[0097] S22. The real vibration source starts working, and the outputs of the unidirectional force measurement sensor 4, unidirectional force compensation sensor 5, and unidirectional acceleration sensor 6 are collected according to the reference sampling frequency and reference sampling time. When measuring the real vibration source, the outputs of the four unidirectional force measurement sensors 4 form the measured voltage matrix U. m (ω):

[0098]

[0099] When measuring the actual vibration source, the inertial force F of the upper mounting plate 1 is calculated using the outputs of four unidirectional acceleration sensors 6. mass-m (ω) is as follows:

[0100]

[0101] Wherein, vector [a z (ω)α x (ω)α y (ω)] T The calculation is as follows:

[0102]

[0103] Among them, F z-mass-m (ω) represents the inertial force of the upper mounting plate in the Z direction when measuring the actual vibration source, through the acceleration a of the upper mounting plate 1 in the Z direction. z (ω) is obtained by multiplying the mass m of mounting plate 1 above; M x-mass-m (ω) represents the inertial torque of the upper mounting plate 1 in the X direction when measuring the actual vibration source, obtained by multiplying the angular acceleration by the moment of inertia J; M y-mass-m (ω) represents the moment of inertia of the upper mounting plate 1 in the Y direction when measuring the actual vibration source, M y-mass-m (ω) and M x-mass-m (ω) is calculated in the same way; a z (ω) represents the acceleration of the upper mounting plate 1 in the Z direction when measuring the actual vibration source, a x (ω) represents the acceleration of the upper mounting plate 1 in the X direction when measuring the actual vibration source, ay (ω) represents the acceleration of the upper mounting plate 1 in the Y direction when measuring the actual vibration source.

[0104] Without considering environmental noise, the inertial force of the mounting plate 1, and the mass of the vibration source and the fundamental frequency of the system, the three-dimensional disturbance force F of the actual vibration source was measured. m The formula for calculating (ω) is as follows:

[0105] F m (ω) 3×1 =G(ω) 3×4 U m (ω) 4×1 +F mass-m (ω) 3×1 ;

[0106] S23, At this time, in order to eliminate environmental noise F env (ω) for the true measured value F real The influence of (ω) requires the environmental noise F to be taken into account. env (ω) Three-dimensional force F without considering environmental noise disturbance m Subtract from (ω) the environmental interference F calculated based on the outputs of the four unidirectional force compensation sensors 5 when measuring the actual vibration source. env (ω) is as follows:

[0107]

[0108] Among them, F j (ω) represents the output force of the j-th unidirectional force compensation sensor 5 when measuring a real vibration source, where j = 1, 2, 3, or 4, and l2 represents the distance between two adjacent unidirectional force compensation sensors 5.

[0109] S24. When measuring the actual vibration source, the actual three-dimensional force F, considering environmental noise, the inertial force of the upper mounting plate 1, the vibration source mass, and the system fundamental frequency, is obtained according to the following formula. real (ω):

[0110]

[0111] Although embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

[0112] The specific embodiments of the present invention described above do not constitute a limitation on the scope of protection of the present invention. Any other corresponding changes and modifications made in accordance with the technical concept of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A method of using a split-range dynamic force measurement platform, the method comprising: Includes the following steps: S1. The load-sharing dynamic force measurement platform includes: a load-sharing column is set between the upper mounting plate and the lower mounting plate, and is located in the center position; Four unidirectional force measurement sensors are evenly arranged between the upper mounting plate and the lower mounting plate, and the unidirectional force measurement sensors are installed in parallel with the load-bearing column; Four unidirectional force compensation sensors are evenly arranged on the upper surface of the lower mounting plate and do not contact the upper mounting plate. Four unidirectional acceleration sensors are evenly distributed on the lower surface of the upper mounting plate and are not in contact with the lower mounting plate; the calibration of the split-load dynamic force measurement platform is carried out in the following steps: S11. Connect the lower mounting plate of the split-load dynamic force measurement platform to the vibration isolation platform, and connect the simulation plate with the same mass as the real vibration source to the upper mounting plate. S12. Connect the outputs of the unidirectional force measurement sensor, the unidirectional force compensation sensor, and the unidirectional acceleration sensor to the signal amplifier and the data acquisition in sequence, and set the reference sampling frequency and the reference sampling time. S13, Obtain the moment of inertia matrix of the split-load dynamic force measurement platform J and mass; S14. Input the known calibration force into the analog chip, use data acquisition to collect the known calibration force, the output of the unidirectional force measurement sensor and the output of the unidirectional acceleration sensor, and calculate the calibration matrix. S2. Dynamic force measurement of real vibration sources: S21. Remove the simulation plate and connect the real vibration source to the upper mounting plate; S22, the real vibration source starts to work, and the output of the one-way force measuring sensor, the one-way force compensation sensor and the one-way acceleration sensor is collected according to the reference sampling frequency and the reference sampling time; the disturbance three-dimensional force F m ( ω ) without considering noise is obtained according to the calibration matrix, the output of the one-way force measuring sensor and the one-way acceleration sensor; S23. Calculate the environmental disturbance F from the output of the unidirectional force compensation sensor env ( ω ) S24, obtaining the real three-dimensional force F according to the following formula real ( ω ): 。 2. The method of using a split-range dynamic force measurement platform of claim 1, wherein, The rotational inertia matrix and mass of the split-load dynamic force measurement platform are obtained through CAD simulation or experiment.

3. The method of using a split-cantilever dynamic force measurement platform of claim 1, wherein, The specific process of S14 is as follows: different known calibration forces are input to the analog piece 3 times, and the three calibration forces are collected by the data collection to form a known three-dimensional force matrix F c ( ω ) as follows: ； wherein, F zi-c ( ω ) represents the input force collected at the i th time, M xi-c ( ω ) represents the X-direction input torque collected at the i th time, M yi-c ( ω ) represents the Y-direction input torque collected at the i th time, i = 1, 2, or 3; The output of the 4 single force measurement sensors forms an output voltage matrix U c ( ω ) as follows: ； wherein, U 1i-c ω U 2i-c ω U 3i-c ω U 4i-c ω T represents the i voltage acquired from the 4 unidirectional force measurement sensors 4 for the​​​​​​​​ The inertial force F of the upper mounting plate is calculated using the outputs of the four single-axis acceleration sensors mass-c ( ω ) as follows: ； ； in, F zi-mass-c ( ω ) indicates the first i The inertial force of the upper mounting plate in the Z direction when the calibration force is input for the first time; M xi-mass-c ( ω ) indicates the first i The moment of inertia of the upper mounting plate in the X direction when the calibration force is input for the first time; M yi-mass-c ( ω ) indicates the first i The moment of inertia of the upper mounting plate in the Y direction when the calibration force is input for the first time; m represents the mass of the upper mounting plate. a zi ( ω () indicates the acceleration of the upper mounting plate in the Z direction. a xi ( ω () indicates the acceleration of the upper mounting plate in the X direction. a yi ( ω () indicates the acceleration of the upper mounting plate in the Y direction. a ki ( ω ) indicates the first i The calibration force was input from the first... k The output acceleration of a unidirectional accelerometer k =1, 2, 3, or 4, l 1 represents the distance between two adjacent unidirectional accelerometers; The calibration matrix G is calculated as follows: ω G = (1 - a) * G0 + a * G1 。 4. The method of using a split dynamic force measurement platform of claim 3, wherein, The three-dimensional force F disturbed by the noise is not considered m ( ω ) is calculated as follows: ； wherein U m ( ω ) represents a measured voltage matrix of the 4 single force measuring sensors when measuring the real vibration source; F mass-m ( ω ) represents the inertial force of the upper mounting plate calculated from the output of the 4 single acceleration measuring sensors when measuring the real vibration source.

5. The method of using a split dynamic force measurement platform of claim 4, wherein, Real three-dimensional force F real ω The calculation formula of the real three-dimensional force F is as follows:​ ； ； wherein F j ( ω ) represents the output force of the i-th unidirectional force compensation sensor when measuring the real vibration source, j j = 1, 2, 3 or 4, l 2 represents the distance between the adjacent two unidirectional force compensation sensors.​ 6. The method of using a split-cantilever dynamic force measurement platform of claim 1, wherein, The upper mounting plate is provided with four bosses for connecting unidirectional force measurement sensors and one boss for connecting the load-bearing column.

7. The method of using a split-cantilever dynamic force measurement platform of claim 1, wherein, The lower mounting plate is provided with four bosses for connecting unidirectional force measurement sensors, four bosses for connecting unidirectional force compensation sensors, and one boss for connecting the load-bearing column.

8. The method of using a split-cantilever dynamic force measurement platform of claim 1, wherein, The lower mounting plate has countersunk holes, and the lower mounting plate is connected to the vibration isolation platform by screws.

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