Method and system for measuring inertial parameters of a rigid body based on the compound pendulum method

Abstract

The present invention discloses a method and system for measuring the inertial parameters of a rigid body based on the compound pendulum method, belonging to the technical field of rigid body measurement. The method includes: using a preset measuring device to respectively test the counterweight mass and the swing period at 0°, 45°, and 90°; based on the principle of the balance lever, using the counterweight masses at 0°, 45°, and 90° to solve the centroid X of the test piece in three directions c , Y c , Z c ; based on the parallel axis theorem of the moment of inertia, the parallel plane theorem of the product of inertia, and the theorem of the moment of inertia about any axis, using the centroid X of the test piece in three directions c , Y c , Z c and the swing period to calculate the inertial parameters of the test piece, where the inertial parameters include the moment of inertia and the product of inertia. This method can achieve one-time installation. By easily rotating the test bench and the test piece to adjust the test posture, the centroid of the measured object in all three directions and six inertial parameters can be tested, and the test accuracy can be calibrated, with high efficiency and high accuracy.

Description

Technical Field

[0001] The present invention relates to the technical field of rigid body measurement, and particularly relates to a method and system for measuring the inertial parameters of a rigid body based on the compound pendulum method. Background Art

[0002] Accurately obtaining the centroid and inertial parameters of a rigid body is the basis for kinematic and dynamic analysis of the rigid body, especially in industries such as automobiles, aerospace, etc. that require precise prediction and analysis of motion postures.

[0003] Currently, in the industry, methods for testing the centroid and inertial parameters of a rigid body include the modal identification method, the torsion pendulum method, and the three-wire pendulum method. The three-wire pendulum method for measuring the moment of inertia of the object to be measured has the advantage of simple equipment, but the disadvantage is that it can only test inertial parameters. The measurement of the centroid requires additional equipment, and the installation of the test piece is time-consuming and laborious, the attitude is not easy to adjust, the positioning is difficult, the test period is long, and the measurement accuracy is difficult to guarantee. The principles of the torsion pendulum method and the compound pendulum method are basically the same. However, when using the torsion pendulum method to measure inertial parameters, it is difficult to well control the adjustment of various placement postures of the object to be measured on the test bench and the measurement of various relative positions, which will have a great impact on the final measurement accuracy, and the test period is long. Although the modal identification method for testing inertial parameters is relatively simple in installation and testing, it is greatly affected by the installation boundary conditions of the test piece, has poor test repeatability, requires high experience of the test personnel, and is not easy to evaluate the test accuracy. Therefore, it has been rarely used in the industry. For example,

[0004] Related Art One describes a rigid body full inertial parameter measurement device and method, which measures the swing period using the principle of the return swing, thereby calculating the inertial parameters and the centroid. This method requires at least 8 adjustments of the attitude of the object to be measured, and each time the attitude of the test piece is adjusted, it needs to be re-positioned relative to the test bench. However, there is no description of a precise positioning device, and the positioning accuracy directly affects the test results. Therefore, the device described in this method not only has a complex test process and a large workload, but also the test accuracy is difficult to guarantee. Related Art Two describes a method for measuring inertial parameters using the operating modal method, mounting the engine power assembly on the test bench according to the vehicle state using mounts, and using the modal test system to test the 6th-order mode of the mount system to identify the inertial parameters of the power assembly. The method has a simple principle and is easy to measure, only requiring one installation. However, the disadvantage is that the repeatability of modal identification is not very good, and the final calculation accuracy is greatly affected by the measurement accuracy of the excitation point and the pickup point positions. Its test accuracy is difficult to evaluate and it is currently less used in the industry. Related Art Three describes a measurement device and method for measuring the inertial parameters of automotive parts using the torsion pendulum method. This measurement device and method can achieve the purpose of testing all inertial parameters with one installation, but the test device is only for small objects to be measured, and the test object is relatively limited. Summary of the Invention

[0005] The present invention aims to solve at least one of the technical problems in the related art to a certain extent.

[0006] To this end, the first object of the present invention is to propose a method for measuring the inertial parameters of a rigid body based on the compound pendulum method.

[0007] The second object of the present invention is to propose a system for measuring the inertial parameters of a rigid body based on the compound pendulum method.

[0008] The third object of the present invention is to propose a computer device.

[0009] The fourth object of the present invention is to propose a non-transitory computer-readable storage medium.

[0010] To achieve the above object, the method for measuring the inertial parameters of a rigid body based on the compound pendulum method according to the first aspect embodiment of the present invention includes: Step S1, using a preset measuring device to respectively test the counterweight mass and the swing period at 0°, 45°, and 90°; Step S2, based on the principle of the balance lever, using the counterweight masses at 0°, 45°, and 90° to solve the centroid of the test piece in three directions , , ; Step S3, based on the parallel axis theorem of the moment of inertia, the parallel plane theorem of the product of inertia, and the theorem of the moment of inertia about any axis, using the centroid of the test piece in three directions , , and the swing periods at 0°, 45°, and 90° to calculate the inertial parameters of the test piece, where the inertial parameters include the moment of inertia and the product of inertia.

[0011] The method for measuring the inertial parameters of a rigid body based on the compound pendulum method according to the embodiment of the present invention can achieve one-time installation. By easily rotating the test bench and the test piece to adjust the test posture, the centroid of the test object in all three directions and six inertial parameters can be tested, and the test accuracy can be calibrated, which is simple, efficient, and highly accurate.

[0012] In addition, the method for measuring the inertial parameters of a rigid body based on the compound pendulum method according to the above embodiment of the present invention may further have the following additional technical features:

[0013] Further, in an embodiment of the present invention, the step S1 specifically includes: Step S101, unifying the X, Y, Z coordinate systems and the positive directions of the test piece and the preset measuring device; Step S102, calibrating the inertial parameters of the preset measuring device at 0°, 45°, and 90°; Step S103, installing the test piece on the preset measuring device, and the rotation axis of the test piece is parallel to the swing axis of the preset measuring device; Step S104, adding a preset counterweight on the light side and recording the counterweight weight and measure the distance between the counterweight and the swing center , while measuring the centroid in the Y direction ; Step S105, remove the preset counterweight block, and swing the test piece around the swing axis of the preset measuring device to measure the swing period ; Step S106, make the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device, and swing the test piece to measure the swing period ; Step S107, make the rotation axis of the test piece form a 90° angle with the swing axis of the preset measuring device, and add a counterweight on the lighter side, and record the weight of the counterweight and measure the distance between the counterweight and the swing center , measure the centroid in the X direction ; Step S108, remove the preset counterweight block, and swing the test piece around the swing axis of the preset measuring device to measure the swing period ; Step S109, rotate the test piece 45° along the installation axis of the test piece, and swing the test piece to measure the swing period ; Step S110, rotate the test piece 90° along the installation axis of the test piece, and swing the test piece to measure the swing period ; Step S111, make the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device, and swing the test piece to measure the swing period ; Step S112, make the rotation axis of the test piece form a 90° angle with the swing axis of the preset measuring device, and add a counterweight on the lighter side, and record the weight of the counterweight and measure the distance between the counterweight and the swing center , measure the centroid in the Z direction .

[0014] Further, in an embodiment of the present invention, a scriber is installed on the preset measuring device, and a light sensor needs to be placed outside the scriber. When the scriber passes through the light sensor to generate a pulse signal, an ultra-low frequency period meter is used to record the pulse signal, and then the swing period is measured , the swing period , the swing period , the swing period , the swing period and the swing period .

[0015] Further, in an embodiment of the present invention, step S3 specifically includes: step S301, calculate during the measurement of the swing period When the centroid position of the entire swinging part of the preset measuring device relative to the centroid of the cycloid and , and then solve the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece Step S302, calculate the centroid position of the entire swinging part of the preset measuring device relative to the cycloid during the measurement swing period When and , and then solve the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece ; Step S303, calculate the centroid position of the entire swinging part of the preset measuring device relative to the cycloid during the measurement swing period When and , and then solve the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece ;

[0016] Step S304, calculate the centroid of the test piece relative to the cycloid in the Y direction during the measurement swing period When , and then solve the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece ; Step S305, calculate the centroid of the test piece relative to the cycloid in the Z direction during the measurement swing period When , and then solve the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece ; Step S306, calculate the centroid of the test piece relative to the cycloid in the X direction during the measurement swing period When , and then solve the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece .

[0017] To achieve the above object, an embodiment of the second aspect of the present invention provides a system for measuring the inertial parameters of a rigid body based on the compound pendulum method, including: a test module for respectively testing the counterweight mass and the swing period at 0°, 45°, and 90° by using a preset measuring device; a centroid solving module for solving the centroids of the test piece in three directions based on the principle of the balance lever by using the counterweight masses at 0°, 45°, and 90° , , ; an inertial parameter solving module for calculating the inertial parameters of the test piece based on the parallel axis theorem of the moment of inertia, the parallel plane theorem of the product of inertia, and the theorem of the moment of inertia about any axis, by using the centroids of the test piece in three directions , , and the swing periods at 0°, 45°, and 90°, wherein the inertial parameters include the moment of inertia and the product of inertia.

[0018] The system for measuring the inertial parameters of a rigid body based on the compound pendulum method according to the embodiment of the present invention can achieve one-time installation. By easily rotating the test bench and the test piece to adjust the test posture, it is possible to test the centroids of all three directions and six inertial parameters of the tested object, and the test accuracy can be calibrated, which is simple, efficient, and accurate.

[0019] In addition, the system for measuring the inertial parameters of a rigid body based on the compound pendulum method according to the above embodiment of the present invention may further have the following additional technical features:

[0020] Further, in an embodiment of the present invention, the test module includes: a unifying unit for unifying the X, Y, and Z coordinate systems and the positive directions of the test piece and the preset measuring device; a calibrating unit for calibrating the inertial parameters of the preset measuring device at 0°, 45°, and 90°; a mounting unit for mounting the test piece on the preset measuring device, and the rotation axis of the test piece is parallel to the swing axis of the preset measuring device; a unit for measuring the centroid in the Y direction for adding a preset counterweight on the lighter side, recording the counterweight weight and measuring the distance from the counterweight to the swing center , and simultaneously measuring the centroid in the Y direction ; a unit for measuring the swing period for removing the preset counterweight block and making the test piece swing around the swing axis of the preset measuring device to measure the swing period ; a unit for measuring the swing period A unit for making the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device and making the test piece swing to measure the swing period ; A measuring X-direction centroid unit for making the rotation axis of the test piece form a 90° angle with the swing axis of the preset measuring device, adding a counterweight to the lighter side, and recording the weight of the counterweight And measuring the distance from the counterweight to the swing center , measuring the X-direction centroid ; Measuring the swing period A unit for removing the preset counterweight block and making the test piece swing around the swing axis of the preset measuring device to measure the swing period ; Measuring the swing period A unit for rotating the test piece 45° along the installation axis of the test piece and making the test piece swing to measure the swing period ; Measuring the swing period A unit for rotating the test piece 90° along the installation axis of the test piece and making the test piece swing to measure the swing period ; Measuring the swing period A unit for making the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device and making the test piece swing to measure the swing period ; A measuring Z-direction centroid unit for making the rotation axis of the test piece form a 90° angle with the swing axis of the preset measuring device, adding a counterweight to the lighter side, and recording the weight of the counterweight And measuring the distance from the counterweight to the swing center , measuring the Z-direction centroid .

[0021] Furthermore, in an embodiment of the present invention, a marking needle is installed on the preset measuring device, and a light sensor needs to be placed outside the marking needle. When the marking needle passes by the light sensor to generate a pulse signal, an ultra-low frequency period meter is used to record the pulse signal, and then the swing period is measured 、the swing period 、the swing period 、the swing period 、the swing period and the swing period .

[0022] Furthermore, in an embodiment of the present invention, the inertia parameter solving module includes: solving the moment of inertia A unit for calculating the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line during the measurement of the swing period ​ and , and then solve for the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally obtain the moment of inertia of the test piece Solve for the moment of inertia unit, for calculating the centroid position of the entire swinging part of the preset measuring device relative to the cycloid during the measurement swing period , and then solve for the distance from the centroid of the entire swinging part to the cycloid and , and then solve for the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally obtain the moment of inertia of the test piece ; Solve for the moment of inertia unit, for calculating the centroid position of the entire swinging part of the preset measuring device relative to the cycloid during the measurement swing period , and then solve for the distance from the centroid of the entire swinging part to the cycloid and , and then solve for the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally obtain the moment of inertia of the test piece ; Solve for the product of inertia unit, for calculating the centroid of the test piece relative to the cycloid in the Y direction during the measurement swing period , and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the cycloid , and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally obtain the product of inertia of the test piece ; Solve for the product of inertia unit, for calculating the centroid of the test piece relative to the cycloid in the Z direction during the measurement swing period , and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the cycloid , and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally obtain the product of inertia of the test piece ; Solve for the product of inertia unit, for calculating the centroid of the test piece relative to the cycloid in the X direction during the measurement swing period , and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the cycloid , and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , and finally obtain the product of inertia of the test piece .

[0023] To achieve the above object, an embodiment of the third aspect of the present invention provides a computer device, including a memory and a processor. The memory stores a computer program, and when the processor executes the computer program, the steps of the method described in any one of the above are implemented.

[0024] To achieve the above object, an embodiment of the fourth aspect of the present invention provides a non-transitory computer-readable storage medium, on which a computer program is stored. When the computer program is executed by a processor, the steps of the method described above are implemented. The additional aspects and advantages of the present invention will be partially given in the following description, partially become obvious from the following description, or be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The above and / or additional aspects and advantages of the present invention will become obvious and easy to understand from the following description of the embodiments in conjunction with the drawings, where:

[0026] Figure 1 is a flowchart of a method for measuring rigid body inertia parameters based on the compound pendulum method according to an embodiment of the present invention;

[0027] Figure 2 is a specific execution diagram of a method for measuring rigid body inertia parameters based on the compound pendulum method according to an embodiment of the present invention;

[0028] Figure 3 is a schematic structural diagram of a preset measuring device according to an embodiment of the present invention;

[0029] Figure 4 is a schematic diagram of test positions according to an embodiment of the present invention, (a) is 0°, (b) is 45°, and (c) is 90°;

[0030] Figure 5 is a schematic diagram of the principle of ultra-low frequency periodic testing according to an embodiment of the present invention.

[0031] Figure 6 is a schematic structural diagram of a system for measuring rigid body inertia parameters based on the compound pendulum method according to an embodiment of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0032] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the accompanying drawings are exemplary and are intended to explain the present invention, but should not be construed as limiting the present invention.

[0033] A method and system for measuring the inertial parameters of a rigid body based on the compound pendulum method according to an embodiment of the present invention will be described below with reference to the accompanying drawings.

[0034] Figure 1 It is a flowchart of a method for measuring the inertial parameters of a rigid body based on the compound pendulum method according to an embodiment of the present invention.

[0035] As Figure 1 and 2 shown, the method for measuring the inertial parameters of a rigid body based on the compound pendulum method includes the following steps:

[0036] In step S1, the counterweight masses and the swing periods at 0°, 45°, and 90° are respectively tested by using a preset measuring device.

[0037] Specifically, in an embodiment of the present invention, step S1 specifically includes:

[0038] Step S101, as Figure 3 shown, the X, Y, and Z coordinate systems and the positive directions of the test piece to be tested and the preset measuring device are unified. It should be noted that the preset measuring device is applicable to all inertial parameter test benches using the compound pendulum principle;

[0039] Step S102, calibrate the inertial parameters of the preset measuring device at 0°, 45°, and 90°. Among them, the calibration method is to let the test bench itself rotate idly once in each angular direction and measure its swing period ;

[0040] Step S103, install the test piece to be tested on the preset measuring device (such as the 0-degree position of the test bench shown in Figure 4 ), and the rotation axis of the test piece to be tested is parallel to the swing axis of the preset measuring device;

[0041] Step S104, add a preset counterweight on the lighter side, record the counterweight weight and measure the distance from the counterweight to the swing center , and at the same time measure the centroid in the Y direction ;

[0042] Step S105, remove the preset counterweight block, give the test piece to be tested a very small swing amount, make the test piece to be tested swing around the swing axis of the preset measuring device, and use an ultra-low frequency period meter to measure the swing period ;

[0043] Step S106: Rotate the frame of the test piece through the central disc of the test bench of the preset measuring device, so that the rotation axis of the test piece forms a 45° angle with the swing axis of the preset measuring device, that is, the test bench is in the 45° test position. Give the test piece a very small swing, and use an ultra-low frequency period meter to measure the swing period. ;

[0044] Step S107: Rotate the frame of the test piece through the central disc of the test bench of the preset measuring device, so that the rotation axis of the test piece forms a 90° angle with the swing axis of the preset measuring device, that is, the test bench is in the 90° test position. Add a counterweight to the lighter side, record the weight of the counterweight and measure the distance of the counterweight from the swing center , and measure the X-direction centroid ;

[0045] Step S108: Remove the preset counterweight block, give the test piece a very small swing amount, make the test piece swing around the swing axis of the preset measuring device, and use an ultra-low frequency period meter to measure the swing period ;

[0046] Step S109: Rotate the test piece along the installation axis of the test piece so that it rotates 45° around the installation axis. Give the test piece a very small swing amount, make it swing around the swing axis of the test bench, and use an ultra-low frequency period meter to record the swing period ;

[0047] Step S110: Rotate the test piece 90° along the installation axis of the test piece to measure the swing period ;

[0048] Step S111: Rotate the frame of the test piece through the central disc of the test bench, so that the rotation axis of the test piece forms a 45° angle with the swing axis of the test bench frame, that is, the test bench is in the 45° test position. Give the test piece a very small swing amount, make it swing around the swing axis of the test bench, and use an ultra-low frequency period calculator to record the swing period ;

[0049] Step S112: Rotate the frame of the test piece through the central disc of the test bench, so that the rotation axis of the test piece forms a 90° angle with the swing axis of the test bench frame, that is, the test bench is in the 90° test position. Add a counterweight to the lighter side, record the weight of the counterweight and measure the distance of the counterweight from the swing center , and measure its Z-direction centroid .

[0050] Further, in an embodiment of the present invention, a scribing needle is installed on a preset measuring device, and a light sensor needs to be placed outside the scribing needle. When the scribing needle passes over the light sensor to generate a pulse signal, an ultra-low frequency period meter is used to record the pulse signal, and then the swing period is measured. Swing period Swing period Swing period Swing period And swing period .

[0051] Specifically, whether based on the compound pendulum method or the torsion pendulum method, or other methods that rely on testing the period to achieve the measurement of inertial parameters, the accuracy and convenience of period measurement are an important part of the final test accuracy. As Figure 5 shown, the embodiment of the present invention adopts a test device and implementation method that can achieve a test period error of less than 0.0005 s. First, a scribing needle is installed on the test bench of the preset measuring device. The scribing needle has strong light absorption. When the test bench swings, the scribing needle passes over the light sensor, and the photosensitive components on the light sensor generate a pulse signal after induction and send it to the ultra-low frequency period meter; in one swing period of the test bench, the pendulum needle passes over the light sensor twice, generating two pulses. The time difference between the two pulses is ∆t. The ultra-low frequency period meter has a high-precision integrated circuit, records the time ∆t between the two pulses, and calculates the swing period T at the same time: ; The ultra-low frequency period meter transmits the period measured each time to the host computer and control software (inertial parameter calculation software, that is, the processing method in step S3) through the USB interface, and the control software records and automatically calculates the inertial parameters.

[0052] In step S2, based on the principle of the balance lever, the centroid of the test piece in three directions is solved by using the counterweight masses at 0°, 45°, and 90°. , , .

[0053] Specifically, using the principle of the balance lever, the centroid of the test piece in three directions is solved , , :

[0054]

[0055]

[0056]

[0057] Among them, Is the counterweight weight, Is the counterweight Distance from the swing center, is the counterweight the distance from the center of swing, is the counterweight the distance from the center of swing, is the weight of the test piece.

[0058] In step S3, based on the parallel axis theorem of moment of inertia, the parallel plane theorem of product of inertia, and the theorem of moment of inertia about any axis, the mass centers of the test piece in three directions are used , , and the swing periods at 0°, 45°, and 90° to calculate the inertia parameters of the test piece, where the inertia parameters include the moment of inertia and the product of inertia.

[0059] Further, in an embodiment of the present invention, step S3 specifically includes:

[0060] Step S301, calculate the position of the centroid of the entire swinging part of the preset measuring device relative to the pendulum line during the measured swing period and and , and then solve the distance from the centroid of the entire swinging part to the pendulum line , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece , and the specific solution process is as follows:

[0061] First, calculate the position of the centroid of the entire swinging part (the swinging part of the test bench + the test piece) relative to the pendulum line during the measured swing period :

[0062]

[0063]

[0064] where is the weight of the object to be measured, is the weight of the swinging part of the test bench, a known quantity, , are respectively the centroid of the swinging part of the test bench in the Y direction and the centroid in the Z direction relative to the pendulum line, which are known quantities.

[0065] Then, calculate the distance from the centroid of the entire swinging part to the pendulum line :

[0066]

[0067] Next, calculate the moment of inertia of the entire swinging part :

[0068]

[0069] wherein, is the local acceleration of gravity;

[0070] Finally, solve for the moment of inertia of the test piece :

[0071]

[0072] wherein, is the moment of inertia of the pendulum axis of the swinging part of the test bench, a known quantity, is the distance between the installation axis of the test piece and the pendulum line, a known quantity.

[0073] Step S302, calculate the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line during the measurement swing period and and , and then solve for the distance of the centroid of the entire swinging part from the pendulum line , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece , and the specific solution process is as follows:

[0074] First, calculate the centroid position of the entire swinging part (the swinging part of the test bench + the test piece) relative to the pendulum line during the measurement swing period :

[0075]

[0076]

[0077] wherein, is the weight of the object to be measured, is the weight of the swinging part of the test bench, a known quantity, , are respectively the centroid of the swinging part of the test bench in the X direction and the centroid in the Z direction relative to the pendulum line, which are known quantities.

[0078] Then, calculate the distance of the centroid of the entire swinging part from the pendulum line :

[0079]

[0080] Then, calculate the moment of inertia of the entire swinging part :

[0081]

[0082] wherein, is the local acceleration of gravity;

[0083] Finally, solve for the moment of inertia of the test specimen :

[0084]

[0085] wherein, is the moment of inertia of the pendulum shaft of the swinging part of the test bench, a known quantity, is the distance between the axis of the test specimen installation and the pendulum line, a known quantity;

[0086] Step S303, calculate the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line during the measured swing period and and then solve for the distance of the centroid of the entire swinging part from the pendulum line and the moment of inertia of the entire swinging part , and finally the moment of inertia of the test specimen , the specific solution process:

[0087] First, calculate the centroid position of the entire swinging part (swinging part of the test bench + test specimen) relative to the pendulum line during the measured swing period :

[0088]

[0089]

[0090] wherein, is the weight of the object to be measured, is the weight of the swinging part of the test bench, a known quantity, , are respectively the centroid of the swinging part of the test bench in the X direction and the centroid in the Y direction relative to the pendulum line, which are known quantities.

[0091] Then, calculate the distance of the centroid of the entire swinging part from the pendulum line :

[0092]

[0093] Next, calculate the moment of inertia of the entire swinging part :

[0094]

[0095] wherein, is the local acceleration of gravity;

[0096] Finally, solve for the moment of inertia of the test specimen :

[0097] ​

[0098] Among them, is the moment of inertia of the pendulum shaft of the swinging part of the test bench, a known quantity, is the distance between the installation axis of the test piece and the pendulum line, a known quantity;

[0099] Step S304, calculate the centroid of the test piece relative to the pendulum line in the Y direction when measuring the swing period and then solve the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line , and and , the distance from the centroid of the entire swinging part to the pendulum line , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece . The specific solution process is as follows:

[0100] First, calculate the centroid of the measured object relative to the pendulum line in the Y direction at the measurement position ;

[0101]

[0102] Then, calculate the centroid position of the entire swinging part (the swinging part of the test bench + the test piece) relative to the pendulum line when measuring the swing period :

[0103]

[0104]

[0105] Next, calculate the distance from the centroid of the entire swinging part to the pendulum line :

[0106]

[0107] Next, calculate the moment of inertia of the entire swinging part :

[0108]

[0109] Among them, is the local acceleration of gravity;

[0110] Finally, use the formula for the product of inertia of a rigid body about any axis to calculate :

[0111]

[0112] ;

[0113] Step S305, calculate the centroid of the test piece relative to the centroid of the pendulum line in the Z direction when measuring the swing period and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line , and the distance between the centroid of the entire swinging part and the pendulum line , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece . The specific solution process is the same as that in Step S303. The specific solution process is as follows: First, calculate the centroid of the object under test relative to the centroid of the pendulum line in the Z direction at the test

[0114] position ;

[0115]

[0116] Then, calculate the centroid position of the entire swinging part (the swinging part of the test bench + the test piece) relative to the pendulum line when measuring the swing period :

[0117]

[0118]

[0119] Next, calculate the distance between the centroid of the entire swinging part and the pendulum line :

[0120]

[0121] Next, calculate the moment of inertia of the entire swinging part :

[0122]

[0123] where is the local acceleration due to gravity;

[0124] Finally, use the formula for the product of inertia of a rigid body about any axis to calculate :

[0125]

[0126] ;

[0127] Step S306, calculate the centroid of the test piece relative to the centroid of the pendulum line in the X direction when measuring the swing period and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line ​​and , the distance from the centroid of the entire swinging part to the cycloid , the moment of inertia of the entire swinging part , the product of inertia of the final test piece , the specific solution process is the same as that in step S303. The specific solution process is as follows:

[0128]

[0129] Then calculate the measured swing period When, the centroid position of the entire swinging part (the swinging part of the test bench + the test piece) relative to the cycloid:

[0130]

[0131]

[0132] Among them, is the centroid in the Y direction of the swinging part of the test bench at this test position, a known quantity;

[0133] Then calculate the distance from the centroid of the entire swinging part to the cycloid :

[0134]

[0135] Then calculate the moment of inertia of the entire swinging part :

[0136]

[0137] Among them, is the local acceleration of gravity;

[0138] Finally, use the formula for the product of inertia of a rigid body about any axis to calculate :

[0139]

[0140] .

[0141] According to the method for measuring the inertial parameters of a rigid body based on the compound pendulum method proposed in the embodiment of the present invention, the test piece only needs to be installed once to measure all three centroid positions and six inertial parameters of the object to be measured, without being affected by boundary conditions, and has the characteristics of high test efficiency, high precision, and good repeatability. At the same time, a method for periodically calibrating the test accuracy is provided to ensure that the test accuracy meets the engineering requirements.

[0142] Next, describe the system for measuring the inertial parameters of a rigid body based on the compound pendulum method proposed in the embodiment of the present invention with reference to the accompanying drawings.

[0143] Figure 6 It is a schematic structural diagram of a system for measuring the inertial parameters of a rigid body based on the compound pendulum method according to an embodiment of the present invention.

[0144] As Figure 6 shown, the system 60 includes: a test module 601, a centroid solving module 602, and an inertial parameter solving module 603.

[0145] Among them, the test module 601 is used to respectively test the counterweight mass and the swing period at 0°, 45°, and 90° by using a preset measuring device. The centroid solving module 602 is used to solve the centroid of the test piece in three directions based on the principle of the balance lever by using the counterweight masses at 0°, 45°, and 90° , , . The inertial parameter solving module 603 is used to calculate the inertial parameters of the test piece based on the parallel axis theorem of the moment of inertia, the parallel plane theorem of the product of inertia, and the theorem of the moment of inertia about any axis, by using the centroid of the test piece in three directions , , and the swing periods at 0°, 45°, and 90°, where the inertial parameters include the moment of inertia and the product of inertia.

[0146] Furthermore, in an embodiment of the present invention, the test module 601 includes:

[0147] A unifying unit, which is used to unify the X, Y, Z coordinate systems and the positive directions of the test piece and the preset measuring device;

[0148] A calibrating unit, which is used to calibrate the inertial parameters of the preset measuring device at 0°, 45°, and 90°;

[0149] An installing unit, which is used to install the test piece on the preset measuring device, and the rotation axis of the test piece is parallel to the swing axis of the preset measuring device;

[0150] A unit for measuring the centroid in the Y direction, which is used to add a preset counterweight on the lighter side, record the weight of the counterweight and measure the distance between the counterweight and the swing center , and at the same time measure the centroid in the Y direction ;

[0151] A unit for measuring the swing period , which is used to remove the preset counterweight block and make the test piece swing around the swing axis of the preset measuring device to measure the swing period ;

[0152] A unit for measuring the swing period , which is used to make the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device and make the test piece swing to measure the swing period ;

[0153] Measure the centroid unit in the X direction, which is used to make the rotation axis of the test piece perpendicular to the swing axis of the preset measuring device, add a counterweight on the lighter side, record the weight of the counterweight and measure the distance of the counterweight from the swing center , measure the centroid in the X direction ;

[0154] Measure the swing period Unit, which is used to remove the preset counterweight block, make the test piece swing around the swing axis of the preset measuring device, so as to measure the swing period ;

[0155] Measure the swing period Unit, which is used to rotate the test piece 45° along the installation axis of the test piece and make the test piece swing, so as to measure the swing period ;

[0156] Measure the swing period Unit, which is used to rotate the test piece 90° along the installation axis of the test piece and make the test piece swing, so as to measure the swing period ;

[0157] Measure the swing period Unit, which is used to make the rotation axis of the test piece form an angle of 45° with the swing axis of the preset measuring device and make the test piece swing, so as to measure the swing period ;

[0158] Measure the centroid unit in the Z direction, which is used to make the rotation axis of the test piece perpendicular to the swing axis of the preset measuring device, add a counterweight on the lighter side, record the weight of the counterweight and measure the distance of the counterweight from the swing center , measure the centroid in the Z direction .

[0159] Furthermore, in an embodiment of the present invention, a scriber is installed on the preset measuring device, and a light sensor needs to be placed outside the scriber. When the scriber passes through the light sensor to generate a pulse signal, an ultra-low frequency period meter is used to record the pulse signal, and then the swing period is measured 、Swing period 、The swing period 、Swing period 、Swing period And swing period .

[0160] Furthermore, in an embodiment of the present invention, the inertia parameter solving module 603 includes:

[0161] Solve the moment of inertia a unit for calculating the centroid position of the entire swinging part of a preset measuring device relative to the cycloid during the measurement of the swinging period and further solving the distance between the centroid of the entire swinging part and the cycloid and the moment of inertia of the entire swinging part and finally obtaining the moment of inertia of the test piece ;

[0162] Solving the moment of inertia a unit for calculating the centroid position of the entire swinging part of a preset measuring device relative to the cycloid during the measurement of the swinging period and further solving the distance between the centroid of the entire swinging part and the cycloid and the moment of inertia of the entire swinging part and finally obtaining the moment of inertia of the test piece ; ;

[0163] Solving the moment of inertia a unit for calculating the centroid position of the entire swinging part of a preset measuring device relative to the cycloid during the measurement of the swinging period and further solving the distance between the centroid of the entire swinging part and the cycloid and the moment of inertia of the entire swinging part and finally obtaining the moment of inertia of the test piece ; ;

[0164] Solving the product of inertia a unit for calculating the centroid of the test piece relative to the centroid of the cycloid in the Y direction during the measurement of the swinging period and further solving the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and the distance between the centroid of the entire swinging part and the cycloid and the moment of inertia of the entire swinging part and finally obtaining the product of inertia of the test piece ;

[0165] Solving the product of inertia a unit for calculating the centroid of the test piece relative to the centroid of the cycloid in the Z direction during the measurement of the swinging period and further solving the centroid position of the entire swinging part of the preset measuring device relative to the cycloid and the distance between the centroid of the entire swinging part and the cycloid and , the moment of inertia of the entire swing part , and finally the inertia product of the tested object is obtained ;

[0166] Solving for the product of inertia Unit used to calculate the swing period in the measurement The center of mass of the tested object relative to the center of mass of the cycloid in the X direction , and then solve the center of mass position of the entire swing part of the preset measuring device relative to the cycloid and , the distance between the center of mass of the entire oscillating part and the cycloid , the moment of inertia of the entire swing part , and finally the inertia product of the tested object is obtained .

[0167] It should be noted that the above explanations focusing on the method embodiment for measuring the inertia parameters of a rigid body based on the complex pendulum method are also applicable to the system of the embodiment of the present invention, and the implementation principles are similar, which will not be repeated here.

[0168] According to the system for measuring the inertia parameters of a rigid body based on the complex pendulum method proposed in an embodiment of the present invention, the test piece only needs to be installed once to test the center of mass and six inertia parameters of the test object in all three directions. It is not affected by boundary conditions and has the characteristics of high test efficiency, high precision and good repeatability. At the same time, a method for regularly calibrating the test accuracy is provided to ensure that the test accuracy meets engineering requirements.

[0169] In order to implement the above embodiments, the present invention also proposes a computer device, including a memory, a processor, and a computer program stored in the memory and executable on the processor. When the processor executes the computer program, the method for measuring the inertia parameters of a rigid body based on the complex pendulum method as in the above embodiments is implemented.

[0170] In order to implement the above embodiment, the present invention also proposes a non-temporary computer-readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method for measuring the inertia parameters of a rigid body based on the complex pendulum method as in the above embodiment is implemented.

[0171] In the description of this specification, the descriptions referring to terms such as "one embodiment", "some embodiments", "examples", "specific examples", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in any one or N embodiments or examples in a suitable manner. In addition, without contradiction, those skilled in the art can combine and combine the different embodiments or examples described in this specification and the features of different embodiments or examples.

[0172] In addition, the terms "first" and "second" are used only for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "N" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0173] Any process or method description shown in the flowchart or described in other ways herein can be understood to represent a module, segment, or portion of code including one or more N executable instructions for implementing a customized logical function or process, and the scope of the preferred embodiments of the present invention includes additional implementations, where the functions may be executed in a substantially simultaneous manner or in a reverse order according to the functions involved, rather than in the order shown or discussed, which should be understood by those skilled in the art to which the embodiments of the present invention pertain.

[0174] The logic and / or steps represented in the flowchart or otherwise described herein, for example, can be considered as a definite sequence list of executable instructions for implementing logical functions, and can be specifically implemented in any computer-readable medium for use by an instruction execution system, apparatus, or device (such as a computer-based system, a system including a processor, or other systems that can fetch and execute instructions from the instruction execution system, apparatus, or device), or in conjunction with these instruction execution systems, apparatuses, or devices. For the purposes of this specification, a "computer-readable medium" can be any device that can contain, store, communicate, propagate, or transport a program for use by or in conjunction with an instruction execution system, apparatus, or device. More specific examples (non-exhaustive list) of computer-readable media include the following: an electrical connection portion (electronic device) having one or N wirings, a portable computer diskette (magnetic device), a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber device, and a portable compact disc read-only memory (CDROM). Additionally, the computer-readable medium can even be paper or other suitable media on which a program can be printed, because the program can be obtained electronically, for example, by optically scanning the paper or other media, followed by editing, interpretation, or other suitable processing as necessary, and then stored in a computer memory.

[0175] It should be understood that the various parts of the present invention can be implemented by hardware, software, firmware, or a combination thereof. In the above-described embodiments, the N steps or methods can be implemented by software or firmware stored in a memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, any one or a combination of the following techniques well known in the art can be used: discrete logic circuits having logic gate circuits for implementing logical functions on data signals, application specific integrated circuits having suitable combinational logic gate circuits, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), and the like.

[0176] Those of ordinary skill in the art of this technology can understand that all or part of the steps carried by the methods of the above embodiments can be completed by a program instructing relevant hardware. The program can be stored in a computer-readable storage medium. When the program is executed, it includes one or a combination of the steps of the method embodiments.

[0177] In addition, each functional unit in various embodiments of the present invention may be integrated into one processing module, may exist physically alone for each unit, or two or more units may be integrated into one module. The above-mentioned integrated module may be implemented in the form of hardware or in the form of a software functional module. When the integrated module is implemented in the form of a software functional module and sold or used as an independent product, it may also be stored in a computer-readable storage medium.

[0178] The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disc, etc. Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A method for measuring the inertial parameters of a rigid body based on the compound pendulum method, characterized in that, it includes the following steps: Step S1, using a preset measuring device to respectively measure the counterweight mass and the swing period at 0°, 45°, and 90°; Step S2, based on the principle of the balance lever, solve the centroid of the test piece in three directions by using the counterweight masses of 0°, 45°, and 90° , , ; Step S3, based on the parallel axis theorem of the moment of inertia, the parallel plane theorem of the product of inertia, and the theorem of the moment of inertia about any axis, use the centroid of the test piece in three directions , , and the swing periods at 0°, 45°, and 90° to calculate the inertia parameters of the test piece, where the inertia parameters include the moment of inertia and the product of inertia; The specific content of step S1 includes: Step S101, unifying the X, Y, and Z coordinate systems and the positive directions of the test piece and the preset measuring device; Step S102, calibrating the inertial parameters of the preset measuring device at 0°, 45°, and 90°; Step S103, installing the test piece on the preset measuring device, and the rotation axis of the test piece is parallel to the swing axis of the preset measuring device; Step S104, add a preset counterweight on the lighter side and record the weight of the counterweight and measure the distance of the counterweight from the center of swing , and measure the centroid in the Y direction at the same time ; Step S105, remove the preset counterweight, and swing the test piece around the swing axis of the preset measuring device to measure the swing period ; Step S106: Make the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device, and swing the test piece to measure the swing period ; Step S107: Make the rotation axis of the test piece form a 90° angle with the swing axis of the preset measuring device, add a counterweight on the lighter side, and record the weight of the counterweight. And measure the distance of the counterweight from the swing center. , measure the centroid in the X direction. ; Step S108, remove the preset counterweight, and swing the test piece around the swing axis of the preset measuring device to measure the swing period ; Step S109, rotate the test piece 45° along the installation axis of the test piece, and swing the test piece to measure the swing period ; Step S110: Rotate the test piece by 90° along the installation axis of the test piece and swing the test piece to measure the swing period ; Step S111: Make the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device, and swing the test piece to measure the swing period ; Step S112: Align the rotation axis of the test piece with the swing axis of the preset measuring device at 90°, add a counterweight on the lighter side, and record the weight of the counterweight. And measure the distance of the counterweight from the swing center. , measure the centroid in the Z direction. ; The specific content of step S3 includes: Step S301, calculate the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line when measuring the swing period, and then solve the distance between the centroid of the entire swinging part and the pendulum line , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece Step S302, calculate the centroid position of the entire swinging part of the preset measuring device relative to the cycloid during the measurement swing period, and then solve for the distance of the centroid of the entire swinging part from the cycloid , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece ; Step S303, calculate the centroid position of the entire swinging part of the preset measuring device relative to the cycloid when measuring the swinging period, and then solve the distance between the centroid of the entire swinging part and the cycloid , the moment of inertia of the entire swinging part , and finally the moment of inertia of the test piece ; Step S304, calculate the centroid of the test piece relative to the centroid of the pendulum line in the Y direction when measuring the swing period and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line , as well as and , the distance between the centroid of the entire swinging part and the pendulum line , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece ; Step S305, calculate the centroid of the test piece in the Z direction relative to the centroid of the pendulum line during the measurement of the swing period when , and then solve the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line and , the distance between the centroid of the entire swinging part and the pendulum line , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece ; Step S306, calculate the centroid of the test piece relative to the centroid of the pendulum line in the X direction during the measurement of the swing period when and then solve for the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line and , the distance between the centroid of the entire swinging part and the pendulum line , the moment of inertia of the entire swinging part , and finally the product of inertia of the test piece .

2. The method for measuring the inertial parameters of a rigid body based on the compound pendulum method according to claim 1, characterized in that, Install a scribing needle on the preset measuring device, and a light sensor needs to be placed outside the scribing needle. When the scribing needle passes over the light sensor to generate a pulse signal, use an ultra-low frequency period meter to record the pulse signal, and then measure the swing period. The swing period The swing period The swing period The swing period And the swing period .

3. A system for measuring the inertial parameters of a rigid body based on the compound pendulum method, characterized in that, it includes: A test module for using a preset measuring device to respectively measure the counterweight mass and the swing period at 0°, 45°, and 90°; The centroid solving module is used to solve the centroid of the test piece in three directions based on the principle of the balance lever and using the counterweight masses at 0°, 45°, and 90° , , ; An inertial parameter solving module, which is configured to calculate the inertial parameters of the test piece by using the parallel axis theorem of the moment of inertia, the parallel plane theorem of the product of inertia, and the theorem of the moment of inertia about any axis, based on the centroid of the test piece in three directions , , , and the swing periods at 0°, 45°, and 90°, where the inertial parameters include the moment of inertia and the product of inertia; The test module includes: A unifying unit for unifying the X, Y, and Z coordinate systems and the positive directions of the test piece and the preset measuring device; A calibrating unit for calibrating the inertial parameters of the preset measuring device at 0°, 45°, and 90°; An installing unit for installing the test piece on the preset measuring device, and the rotation axis of the test piece is parallel to the swing axis of the preset measuring device; Measure the centroid unit in the Y direction, add a preset counterweight to the light side, and record the weight of the counterweight and measure the distance of the counterweight from the center of swing , while measuring the centroid in the Y direction ; Measuring the swing period a unit configured to remove the preset counterweight and swing the test piece around the swing axis of the preset measuring device so as to measure the swing period ; Measuring the swing period a unit for making the rotation axis of the workpiece under test form a 45° angle with the swing axis of the preset measuring device and swinging the workpiece under test to measure the swing period ; Measure the centroid unit in the X direction to make the rotation axis of the test piece form a 90° angle with the swing axis of the preset measuring device, add a counterweight on the lighter side, and record the weight of the counterweight And measure the distance of the counterweight from the swing center , measure the centroid in the X direction ; Measuring the swing period A unit for removing the preset counterweight and causing the test piece to swing about the swing axis of the preset measuring device to measure the swing period ; Measuring the swing period A unit for rotating the test piece by 45° along the installation axis of the test piece and causing the test piece to swing to measure the swing period ; Measuring the swing period A unit for rotating the test piece by 90° along the installation axis of the test piece and causing the test piece to swing to measure the swing period ; Measuring the swing period A unit for making the rotation axis of the test piece form a 45° angle with the swing axis of the preset measuring device, and making the test piece swing to measure the swing period ; A Z-direction centroid measuring unit is used to make the rotation axis of the workpiece under test perpendicular to the swing axis of the preset measuring device, add a counterweight on the lighter side, and record the weight of the counterweight. And measure the distance from the counterweight to the swing center. , measure the Z-direction centroid. ; The inertial parameter solving module includes: Solving the moment of inertia a unit for calculating the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line during the measured swinging period and further solving the distance between the centroid of the entire swinging part and the pendulum line and the moment of inertia of the entire swinging part and finally obtaining the moment of inertia of the test piece ​ Solving for the moment of inertia a unit for calculating the centroid position of the entire swinging part of the preset measuring device relative to the cycloid during the measured swing period and further solving for the distance between the centroid of the entire swinging part and the cycloid and the moment of inertia of the entire swinging part, and finally obtaining the moment of inertia of the test piece to be tested ; ;​ Solving for the moment of inertia Unit used to calculate the swing period during measurement The center of mass position of the entire swinging part of the preset measuring device relative to the cycloid and , and then solve the distance between the center of mass of the entire swinging part and the cycloid , the moment of inertia of the entire swing part , and finally the moment of inertia of the test piece is obtained ; Solving the product of inertia a unit for calculating the centroid of the test piece in the Y direction relative to the centroid of the pendulum wire when measuring the swing period and further solving the centroid position of the entire swinging part of the preset measuring device relative to the pendulum wire and the distance between the centroid of the entire swinging part and the pendulum wire the moment of inertia of the entire swinging part and finally obtaining the product of inertia of the test piece ;​ Solving the product of inertia a unit for calculating the centroid of the test piece in the Z direction relative to the centroid of the pendulum wire when measuring the swing period and further solving the centroid position of the entire swinging part of the preset measuring device relative to the pendulum wire and the distance between the centroid of the entire swinging part and the pendulum wire and the moment of inertia of the entire swinging part and finally obtaining the product of inertia of the test piece ; Solving the product of inertia a unit for calculating the centroid of the test piece in the X direction relative to the centroid of the pendulum line when measuring the swing period and further solving the centroid position of the entire swinging part of the preset measuring device relative to the pendulum line and the distance between the centroid of the entire swinging part and the pendulum line and the moment of inertia of the entire swinging part and finally obtaining the product of inertia of the test piece .

4. The system for measuring the inertial parameters of a rigid body based on the compound pendulum method according to claim 3, characterized in that, Install a scriber on the preset measuring device. A light sensor needs to be placed outside the scriber. When the scriber passes over the light sensor to generate a pulse signal, use an ultra-low frequency period meter to record the pulse signal, and then measure the swing period and the swing period and the swing period and the swing period and the swing period and the swing period .

5. A computer device includes a memory and a processor, and the memory stores a computer program, characterized in that, when the processor executes the computer program, it implements the steps of the method described in any one of claims 1-4.

6. A non-transitory computer-readable storage medium stores a computer program thereon, characterized in that, when the computer program is executed by the processor, it implements the steps of the method described in any one of claims 1-4.

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