A dynamic calibration device and calibration method for a multi-dimensional force sensor

Abstract

The present invention provides a multi-dimensional force sensor dynamic calibration device and calibration method. The calibration device comprises: a calibration platform; sensor calibration hardware mounted on the calibration platform; a dynamic load generating mechanism mounted on the calibration platform; and a dynamic load applying mechanism mounted on the dynamic load generating mechanism. This invention addresses the overly simple and immature nature of existing multi-dimensional force sensor dynamic calibration experiments, while also eliminating the existing drawbacks of the inability to guarantee the location, direction, and force of the strike point.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic calibration, and in particular to a dynamic calibration device and a calibration method for a multi-dimensional force sensor. Background Art

[0002] Six-axis force sensors are used to accurately sense force and torque in industrial production. Similarly, dynamic metrology is a core component of the national quality infrastructure. Due to the complexity of dynamic measurement, immature dynamic metrology technology can affect sensor performance, which in turn impacts industrial production. Existing metrology technologies require further exploration and improvement in both theoretical frameworks and measurement applications.

[0003] In the field of dynamic calibration, sinusoidal signals, step signals, pulse signals, and other excitation sources are commonly used to carry out dynamic calibration activities. In recent years, researchers have designed dynamic force measurement devices for sinusoidal excitation sources. For example, the Physikalisch-Technische Bundesanstalt (PTB) in Germany, the National Laboratory of France (LNE) in France, the Spanish Center for Metrology (CEM), and the Beijing Great Wall Institute of Metrology and Testing (CIMM) have designed sinusoidal force calibration devices. However, the equipment is often expensive, the error is difficult to control, and high-frequency sinusoidal excitation is difficult to achieve. For step signal excitation sources, researchers usually use methods such as material fracture and instantaneous severing of the rope to construct negative step excitation signals. For impact signal excitation sources, the National Institute of Metrology (NIM) and others have completed the development of impact force calibration devices, but they are not applicable to multi-dimensional force sensors.

[0004] Currently, there are no unified international standards or industry specifications for dynamic calibration of six-axis force sensors. In the field of dynamic metrology, typical dynamic force excitation sources are step signals, pulse (impact) signals, and sinusoidal signals. In actual research and production, dynamic calibration often involves instantaneously cutting or burning the rope that holds the load to generate a negative step excitation signal. This method suffers from the following issues: the dynamic excitation type is limited, and the applied excitation magnitude depends on the mass of the load, resulting in generally small excitation values. To address these issues, a dynamic calibration device and method that utilizes a second excitation type—impact—in addition to step excitation has been proposed. This device and method utilizes a swinging hammer to achieve dynamic calibration. While previous researchers have used hammers to strike force sensors, these methods have been limited to dynamic characteristic testing, modal analysis, and preliminary evaluation of parameters such as natural frequency. However, dynamic calibration experiments using hammers present several challenges, including complex tooling, difficulty in setting the strike point, and difficulty in controlling the strike point location, direction, and force, making it difficult to generate a pure impact torque.

[0005] In the graduation thesis of Wang Jinbin, a master's student at Chongqing University in 2021, the use of a pendulum to provide impact excitation appeared for the first time, but the device was relatively simple and not systematic. Chinese patent CN 111579152A provides a six-dimensional force sensor dynamic calibration device and calibration method that loads impact excitation by means of a small ball impact, but the process of adjusting the force direction of the sensor is complicated, time-consuming and labor-intensive, and the excitation source is difficult to trace. Chinese patent CN 110411656A provides a six-dimensional force sensor dynamic calibration device and method that controls the reverse rotation of the servo motor through PLC to form a negative step excitation, but the operation is complicated and there are many components, which makes the calibration result error large, and the cost is high, making it difficult to apply in practice. In summary, the existing technology has the disadvantages of high price, complex structure, and difficulty in realizing errors, making it difficult to apply to six-dimensional force / multi-dimensional force sensors.

[0006] Therefore, it is urgent to design a dynamic calibration device for a six-dimensional force sensor with simple structure and strong practicality, as well as a standardized and normalized dynamic calibration method. Summary of the Invention

[0007] In order to solve the problem that the existing six-dimensional force / torque sensor dynamic calibration experiment form is too single and immature, and to solve the defect that the existing technology cannot guarantee the position, direction and strength of the knocking point, the present invention provides a multi-dimensional force sensor dynamic calibration device and calibration method.

[0008] In a first aspect of the present invention, a multi-dimensional force sensor dynamic calibration device is provided. The device comprises:

[0009] Calibration platform;

[0010] sensor calibration firmware loaded on the calibration platform;

[0011] a dynamic load generating mechanism carried on the calibration platform;

[0012] and a dynamic load loading mechanism carried on the dynamic load generating mechanism.

[0013] According to the above aspects and any possible implementation, an implementation is further provided, wherein the calibration platform includes:

[0014] Calibration table surface;

[0015] A calibration platform base is arranged parallel to and below the calibration platform surface;

[0016] and a plurality of support rods connected between the calibration platform table and the calibration platform base;

[0017] A sensor mounting platform is provided on the calibration platform surface;

[0018] A vibration isolation pad is provided under the base of the calibration platform;

[0019] Two rows of holes are provided on both sides of the edge of the calibration platform surface.

[0020] According to the above aspects and any possible implementation, further provided is an implementation, wherein the sensor calibration firmware includes:

[0021] A calibration base mounted on the sensor mounting platform and a calibration cap disposed above the calibration base; a multi-dimensional force sensor disposed between the calibration base and the calibration cap;

[0022] The calibration cap is used to determine the loading position and direction of the dynamic load, and transfer the dynamic load to the elastic body of the multi-dimensional force sensor; the calibration cap is provided with a raised mark, and the raised mark is used to determine the installation direction; when the calibration cap is installed with the multi-dimensional force sensor, its direction coincides with the detection direction of the multi-dimensional force sensor Fx; because the calibration cap is circular in shape, a mark is required to clarify the direction for easy operation. If the direction is not clear, it is easy to cause ambiguous operation. Screw holes are provided on both the calibration base and the calibration cap, and the screw holes are used to fix the multi-dimensional force sensor;

[0023] The calibration cap is provided with a plurality of loading positions, each loading position being divided into different loading point groups according to the dynamic calibration direction;

[0024] The sensor mounting platform and the calibration base are both provided with a plurality of buckles; the buckles are used to ensure that the calibration base and the sensor mounting platform are relatively stationary during the dynamic calibration process.

[0025] The clip is U-shaped, and the calibration base and the sensor mounting platform are octagonal. When the octagon of the calibration base coincides with that of the sensor mounting platform, the clip can be installed vertically to connect the calibration base and the sensor mounting platform together, and when subjected to impact excitation, the clip is used to ensure the relative stillness and stability of the calibration base and the sensor mounting platform.

[0026] According to the above aspects and any possible implementation, there is further provided an implementation, wherein the dynamic load generating mechanism includes:

[0027] retractable pole;

[0028] a bearing mounted on one end of the telescopic rod;

[0029] and an impact force sensor mounted on the other end of the telescopic rod;

[0030] The axial direction of the telescopic rod is perpendicular to the force direction of the impact force sensor;

[0031] The impact force sensor is provided with a buffer head in the direction of force, and a counterweight is provided in the opposite direction of force. The buffer head is made of any one of stainless steel, aluminum, nylon or rubber.

[0032] According to the above aspects and any possible implementation, there is further provided an implementation, wherein the dynamic load loading mechanism includes:

[0033] A first bottom beam and a second bottom beam installed in parallel above the calibration platform;

[0034] a first vertical beam slidably mounted above the first bottom beam;

[0035] a second vertical beam slidably mounted above the second bottom beam;

[0036] a crossbeam connected between the top of the first vertical beam and the top of the second vertical beam;

[0037] and a mounting mechanism slidably mounted on the first vertical beam, the second vertical beam, or the horizontal beam;

[0038] The mounting mechanism is arranged corresponding to the bearing; the mounting mechanism is mounted on the bearing.

[0039] According to the above aspects and any possible implementation, further provided is an implementation, wherein the mounting mechanism includes:

[0040] a first mounting plate, a second mounting plate, and a mounting portion;

[0041] The first mounting plate is slidably mounted on the first vertical beam, the second vertical beam, or the horizontal beam;

[0042] One end of the second mounting plate is vertically connected to the first mounting plate, and the other end is provided with a mounting portion;

[0043] The bearing is mounted on the mounting portion.

[0044] According to the above aspects and any possible implementation, there is further provided an implementation, wherein a bubble level is provided on the bearing; the bubble level includes a first bubble level and a second bubble level;

[0045] The bearing edge is provided with an angle scale; the angle scale is used to distinguish the dynamic load release height during dynamic calibration. The angle scale is provided along the outer circumference of the bearing edge and includes a short scale set every fifteen degrees and a long scale set every thirty degrees.

[0046] According to the above aspects and any possible implementation manner, an implementation manner is further provided, in which the multi-dimensional force sensor is in the shape of a symmetrical cylinder or square column when viewed from above.

[0047] According to the above aspects and any possible implementation manner, an implementation manner is further provided, wherein the impact force sensor is a piezoelectric impact force sensor.

[0048] In a second aspect of the present invention, a method for dynamic calibration of a multi-dimensional force sensor is provided. The method is implemented using the apparatus described above and comprises:

[0049] (1) Adjust the position of the mounting mechanism and the length of the telescopic rod so that the buffer head contacts the center of the loading group to be calibrated and the bubble level indicator displays a horizontal position;

[0050] (2) Move the piezoelectric impact force sensor to the corresponding position of the bearing and then release it. The dynamic load generating mechanism swings around the bearing to achieve the impact force calibration of the six-dimensional force sensor to be dynamically calibrated in all directions;

[0051] (3) During the impact force calibration process, the voltage output value of the impact force sensor and the output voltage in each direction of the six-dimensional force sensor to be dynamically calibrated are obtained to determine the dynamic calibration data set;

[0052] (4) Based on the dynamic calibration data set, the input data of the impact force sensor in each direction is formed into an input matrix, and the output voltage values ​​of the multi-dimensional force sensor in each direction is formed into an output matrix. The dynamic model of the six-dimensional force sensor is determined based on the input matrix and the output matrix to complete the calibration.

[0053] Compared with the prior art, the present invention has the following beneficial effects:

[0054] (1) The dynamic excitation source applied by the six-dimensional / multi-dimensional force sensor dynamic calibration device described in the present invention is an impact signal, which solves the problem that most laboratories currently use negative step excitation as the excitation source for dynamic calibration experiments, and the excitation source type is single. The present invention has the characteristics of simple structure, easy operation, good experimental repeatability, and small error.

[0055] (2) The calibration base and the mounting table in the present invention are connected by bearings. During dynamic calibration, the calibration direction is changed by rotating the calibration base. The mechanism is simple and easy to operate. In addition, multiple sets of clips are provided between the calibration base and the mounting table. When dynamic calibration is performed in a certain calibration direction, the clips ensure that the sensor to be calibrated and the calibration table are relatively still. The clips are simple to install and quick and convenient to use. The present invention solves the problem of complex operation and heavy workload in changing the calibration direction during dynamic calibration, and effectively avoids related errors.

[0056] (3) The slidable vertical beam, telescopic rod, and mounting mechanism that can slide on the horizontal beam in the present invention can conveniently and quickly adjust the striking position of the hammer head during the dynamic calibration process. By setting up two levels, it is possible to help adjust the loading direction and ensure that the loading direction is perpendicular to the loading surface, thereby conveniently and effectively ensuring the controllability of the position and direction of the loading point of the dynamic excitation source. By setting up corresponding angle scales around the bearing, the release position (height) of the dynamic load generating device can be accurately controlled. The present invention solves the problem of the existing method that personnel use a handheld impact hammer to strike and cannot control the force value, point position, and direction, thereby improving the repeatability of the dynamic calibration experiment.

[0057] (4) In the prior art, the impact force value is usually measured indirectly by using an acceleration sensor / displacement sensor. The dynamic load generating device of the present invention adopts a high-precision piezoelectric impact force sensor, which solves the problem in the prior art that the dynamic excitation source is difficult to trace and the error cannot be guaranteed.

[0058] (5) The piezoelectric impact force sensor of the present invention is equipped with a buffer head made of various materials such as stainless steel, aluminum, nylon or rubber, which can achieve dynamic excitation of different frequencies and is suitable for dynamic calibration of various sensors.

[0059] (6) The calibration cap in the present invention is provided with different loading groups to facilitate distinguishing the knocking positions of different calibration directions.

[0060] (7) The vibration isolation pad in the present invention can minimize the impact of irrelevant vibrations.

[0061] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present invention, nor are they intended to limit the scope of the present invention. Other features of the present invention will become readily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0062] The above and other features, advantages and aspects of the embodiments of the present invention will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, wherein:

[0063] Figure 1 A schematic structural diagram of a dynamic calibration device provided by an embodiment of the present invention is shown;

[0064] Figure 2 A schematic diagram of the structure of the sensor calibration firmware provided by an embodiment of the present invention is shown;

[0065] Figure 3 A schematic structural diagram of a dynamic load generating mechanism provided by an embodiment of the present invention is shown;

[0066] Figure 4 A schematic structural diagram of a mounting mechanism provided by an embodiment of the present invention is shown;

[0067] Figure 5 A schematic structural diagram of a buckle provided by an embodiment of the present invention is shown;

[0068] Figure 6 The structure of the calibration cap provided by the embodiment of the present invention is shown Figure 1 ;

[0069] Figure 7 The structure of the calibration cap provided by the embodiment of the present invention is shown Figure 2 .

[0070] in, Figures 1 to 6 The corresponding relationship between the reference numerals and component names is as follows:

[0071] 1 Calibration table base, 2 support rod, 3 calibration table top, 4 sensor mounting table, 5 first bottom beam, 6 second bottom beam, 7 first vertical beam, 8 second vertical beam, 9 horizontal beam, 10 first mounting mechanism, 11 second mounting mechanism, 12 calibration base, 13 multi-dimensional force sensor, 14 calibration cap, 15 telescopic rod, 16 bearing, 17 impact force sensor, 18 buffer head, 19 counterweight, 20 first bubble level, 21 second bubble level, 22 angle scale, 23 raised mark, 24 first loading group a surface, 25 first loading group c surface, 26 second loading group a surface, 27 second loading group c surface, 28 third loading group a surface, 29 third loading group b surface, 30 fourth loading group a surface, 31 first loading group b surface, 32 first loading group d surface, 33 second loading group b surface, 34 second loading group d surface. DETAILED DESCRIPTION

[0072] To make the objectives, technical solutions, and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0073] In this document, the term "and / or" simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, or B exists alone. Furthermore, the character " / " in this document generally indicates that the related objects are in an "or" relationship.

[0074] The multi-dimensional force sensor dynamic calibration device in the present invention not only avoids the previous single type of dynamic excitation source, but also can control the force value, application position and application direction of the impact excitation. It has high experimental repeatability, is applicable to a wide range of sensors, and has the characteristics of simple structure, convenient operation, high calibration accuracy, and low calibration error.

[0075] In this embodiment, a six-dimensional force sensor is used as an example to introduce the multi-dimensional force sensor dynamic calibration device and calibration method of the present invention. Figures 1 to 4 The multi-dimensional force sensor dynamic calibration device and calibration method provided by the embodiments of the present invention are described.

[0076] In a first aspect of an embodiment of the present invention, a multi-dimensional force sensor dynamic calibration device is provided. Figure 1 As shown, the device includes: a calibration platform, a sensor calibration firmware, a dynamic load generating mechanism and a dynamic load loading mechanism.

[0077] Specifically, the calibration platform is used to install other mechanisms, and plays a role in vibration isolation and reducing other vibrations. The sensor calibration firmware, which is carried on the calibration platform, is used to fix the sensor to be calibrated on the calibration platform, and can receive impact force and transmit the impact force to the sensor. The dynamic load generating mechanism, which is carried on the calibration platform, is used to release the pendulum at different positions and heights without initial velocity, to generate repeatable impact forces of different sizes, and adjust the position and direction of dynamic load application. The dynamic load loading mechanism, which is carried on the dynamic load generating mechanism, is used to suspend the dynamic load generating mechanism and adjust the position and direction of dynamic load application.

[0078] In this embodiment, if Figure 1 As shown, the calibration platform includes:

[0079] Calibration table surface 3;

[0080] A calibration platform base 1 is arranged parallel to and below the calibration platform surface 3;

[0081] And a plurality of support rods 2 connected between the calibration platform surface 3 and the calibration platform base 1.

[0082] Specifically, a sensor mounting platform 4 is provided on the calibration platform surface 3; a vibration isolation pad is provided below the calibration platform base 1; and two rows of holes are provided on either side of the edge of the calibration platform surface 3 for mounting a first bottom beam 5 and a second bottom beam 6. Because the multi-dimensional force sensor 13 and the calibration platform surface 3 need to be fixed when dynamically calibrating a certain direction, and the multi-dimensional force sensor 13 needs to be rotated when changing the calibration direction, a sensor mounting platform 4 is designed on the calibration platform surface 3. Its shape corresponds to the calibration platform base 1, and it can be fixed by installing a clip and rotated by removing the clip.

[0083] A sensor mounting platform 4 is located in the center of the calibration platform's top surface 3. A cylindrical base is located in the center of the sensor mounting platform 4, which serves as the calibration base for the sensor calibration hardware. Two rows of holes are installed on either side of the edge of the calibration platform 3 to secure the first and second bottom beams 5 and 6 of the dynamic load-applying mechanism. To account for the impact of other environmental factors on the dynamic response of the multi-dimensional force sensor, vibration isolation pads are placed beneath the base.

[0084] In this embodiment, if Figure 2 As shown, the sensor calibration firmware includes:

[0085] A calibration base 12 mounted on the sensor mounting platform 4;

[0086] and a calibration cap 14 disposed above the multi-dimensional force sensor 13 .

[0087] Specifically, the calibration base 12 secures the multi-dimensional force sensor 13 to the calibration platform. The multi-dimensional force sensor 13 to be dynamically calibrated is mounted above the calibration base 12. The calibration cap 14 determines the position and direction of the dynamic load and transfers the dynamic load to the elastic body of the multi-dimensional force sensor 13.

[0088] In this embodiment, screw holes are provided on the calibration base 12 and the calibration cap 14, and the screw holes are used to fix and install the multi-dimensional force sensor 13; multiple loading positions are provided on the calibration cap 14, and each loading position is divided into different loading point groups according to the dynamic calibration direction.

[0089] Specifically, the sensor mounting platform 4 and the calibration base 12 are both provided with a plurality of buckles, which are used to ensure the relative stillness of the calibration base 12 and the sensor mounting platform 4 during the dynamic calibration process. There are eight buckles, which ensure good fixing effect and stability after installation. Figure 5 As shown, the buckle is U-shaped, and the shapes of the calibration base 12 and the sensor mounting platform 4 are correspondingly set, both including a mounting body and eight positioning parts arranged along the outer periphery of the mounting body. When the calibration base 12 coincides with the eight positioning parts of the sensor mounting platform 4, the buckle is vertically installed to connect the calibration base 12 and the sensor mounting platform 4 together, and when subjected to impact excitation, the buckle is used to ensure the relative stillness and stability of the calibration base 12 and the sensor mounting platform 4.

[0090] Both the calibration base 12 and the calibration cap 14 are provided with screw holes for fixing the multi-dimensional force sensor 13. The calibration cap 14 is provided with loading positions distributed on the calibration cap 14. The loading positions are divided into different first loading point groups, second loading point groups, third loading point groups, and fourth loading point groups according to the dynamic calibration direction.

[0091] In this embodiment, if Figure 3 As shown, the dynamic load generating mechanism includes: a telescopic rod 15, a bearing 16 and an impact force sensor 17. The axial direction of the telescopic rod 15 is perpendicular to the force direction of the impact force sensor 17. The dynamic load generating mechanism can be understood as a pendulum with an adjustable hammer handle length, a hammer body itself being a piezoelectric impact force sensor, a variety of buffer heads, a counterweight at the rear, and a bearing installed at the hammer tail. The telescopic rod 15 is used to adjust the length. The bearing 16 is installed at one end of the telescopic rod 15 for the smooth swing of the pendulum. The impact force sensor 17 is installed at the other end of the telescopic rod 15 for measuring the force value of the impact load. Preferably, the impact force sensor 17 is a piezoelectric impact force sensor.

[0092] In this embodiment, the impact force sensor 17 is provided with a buffer head 18 in the direction of force application and a counterweight 19 in the opposite direction of force application. The buffer head 18 is used to broaden the load frequency, enabling dynamic calibration experiments for a variety of sensors. Preferably, the buffer head 18 is made of stainless steel, aluminum, nylon, or rubber.

[0093] In this embodiment, a bubble level is provided on the bearing 16; the bubble level includes a first bubble level 20 and a second bubble level 21; the bubble level is used to determine whether the load application direction is perpendicular to the loading surface, so as to facilitate adjustment of the application direction of the impact load.

[0094] In this embodiment, the edge of the bearing 16 is provided with an angle scale 22. The angle scale 22 is used to distinguish the height at which the dynamic load is released during the dynamic calibration process. The angle scale 22 is an angle scale used to clearly indicate the position / height at which the dynamic load generating device is released, thereby ensuring the repeatability of the dynamic calibration experiment.

[0095] Specifically, the telescopic rod 15 can be extended and shortened. The bearing 16 is fixed to the end of the telescopic rod 15 and is responsible for performing circular motion around the mounting mechanism. A piezoelectric impact force sensor 17 is fixed to the other end of the telescopic rod 15, and the direction of the telescopic rod 15 is maintained at 90 degrees perpendicular to the force direction of the impact force sensor 17. The force direction of the piezoelectric impact force sensor 17 is available in a variety of buffer heads 18 of different materials, such as stainless steel, aluminum, nylon, rubber, etc., and counterweights 19 of different masses are installed in the opposite direction of the force direction to generate dynamic loads of different sizes. The bubble level is installed at the connection between the bearing 16 and the telescopic rod 15.

[0096] In this embodiment, if Figure 1 As shown, the dynamic load loading mechanism includes:

[0097] A first bottom beam 5 and a second bottom beam 6 are installed in parallel above the calibration platform;

[0098] A first vertical beam 7 slidably mounted above the first bottom beam 5;

[0099] A second vertical beam 8 slidably mounted above the second bottom beam 6;

[0100] a transverse beam 9 connected between the top of the first vertical beam 7 and the top of the second vertical beam 8;

[0101] And a mounting mechanism slidably mounted on the first vertical beam 7 or the second vertical beam 8 or the horizontal beam 9.

[0102] Specifically, the mounting mechanism is arranged corresponding to the bearing 16; the mounting mechanism is mounted on the bearing 16. The first vertical beam 7 and the second vertical beam 8 are respectively installed with the first bottom beam 5 and the second bottom beam 6, and can slide along the installation direction of the first bottom beam 5 and the second bottom beam 6. When performing dynamic calibration, it is necessary to use aluminum profile right-angle brackets to reinforce the connection. The cross beam 9 is installed and fixed to the first vertical beam 7 and the second vertical beam 8 through aluminum profile right-angle connectors. In addition, in the grooves of the first vertical beam 7 and the cross beam 9, there are specially processed slidable first mounting mechanisms 10 and second mounting mechanisms 11, which can mount the bearings 16 in the dynamic load generating device.

[0103] The first bottom beam 5 and the second bottom beam 6 are installed on the calibration table surface 3, and are used to connect the dynamic load loading mechanism and the calibration table, wherein the first vertical beam 7 and the second vertical beam 8 can slide along the corresponding bottom beam to adjust the position. A mounting mechanism is provided on the two vertical beams. The crossbeam is fixed to the two vertical beams, and a mounting mechanism is designed on the crossbeam. The dynamic load loading mechanism is used to mount the dynamic load generating mechanism, and the two are connected through the mounting mechanism. By moving the position of the vertical beam on the bottom beam, moving the position of the mounting mechanism, and then adjusting the length of the telescopic rod, the knocking position of the buffer head can be vertically aligned with the loading surface. Each vertical beam, bottom beam and cross beam is made of aluminum profiles, which is light in material and can slide through a slide.

[0104] In this embodiment, if Figure 4 As shown, the mounting mechanism includes:

[0105] a first mounting plate, a second mounting plate, and a mounting portion;

[0106] The first mounting plate is slidably mounted on the first vertical beam or the second vertical beam or the horizontal beam 9;

[0107] One end of the second mounting plate is vertically connected to the first mounting plate, and the other end is provided with a mounting portion;

[0108] The bearing 16 is mounted on the mounting portion.

[0109] In a second aspect of the present invention, a calibration method for the calibration device is provided, the method comprising:

[0110] (1) Adjust the position of the mounting mechanism and the length of the telescopic rod 15 so that the buffer head 18 contacts the center of the loading group to be calibrated and the bubble level indicator displays a horizontal level;

[0111] (2) Manually pick up the piezoelectric impact force sensor 17 and release it, and the dynamic load generating mechanism swings around the bearing 16 to achieve the impact force calibration of the multi-dimensional force sensor 13 to be dynamically calibrated in all directions;

[0112] (3) During the impact force calibration process, the voltage output value of the impact force sensor 17 and the output voltages in each direction of the multi-dimensional force sensor 13 to be dynamically calibrated are obtained to determine a dynamic calibration data set;

[0113] (4) Based on the dynamic calibration data set, the input data of the impact force sensor 17 in each direction is formed into an input matrix, and the output voltage values ​​of the multi-dimensional force sensor 17 (a six-dimensional force sensor in this embodiment) in each direction is formed into an output matrix. The dynamic model of the multi-dimensional force sensor is determined based on the input matrix and the output matrix to complete the calibration.

[0114] Specifically, when using the above-mentioned dynamic calibration device to dynamically calibrate a six-dimensional force sensor, the various components must be assembled first. First, the sensor calibration firmware must be installed. The calibration cap must be installed on the top of the six-dimensional force sensor, and the calibration base must be installed on the bottom of the six-dimensional force sensor. The three installation directions must be consistent. Then, the calibration base and the calibration table sensor mounting platform must be installed, and the clips must be locked on the eight protrusions. Finally, the dynamic load generator and the right-angle mounting mechanism on the beam must be installed.

[0115] For a six-dimensional force sensor, it can sense all force information in three-dimensional space, that is, the corresponding three-dimensional orthogonal forces Fx, Fy, Fz and three-dimensional orthogonal moments Mx, My, Mz. For ease of description, as Figure 6 and Figure 7As shown, during the dynamic calibration of the six-dimensional force sensor, the loading groups are divided into a first loading group, a second loading group, a third loading group, and a fourth loading group, each of which includes surface a, surface b, surface c, and surface d. For example, for Fx, it is only necessary to complete the tapping and rotation of surface a 24 of the first loading group, and then complete the tapping of surface b 31 of the first loading group to complete the impact force calibration of the multi-dimensional force sensor in the Fx direction, forming an Fx dynamic calibration data set. Moreover, during the adjustment process of the same loading group, due to the design of the eight positioning parts, no adjustment is required after rotation, making the present invention simple to operate. For example, during the dynamic calibration process of Fx Fy, the loading mechanism is first adjusted, the buffer head 18 contacts the center of the first loading group a surface 24 and the first bubble level 20 displays horizontal. After knocking the first loading group a surface 24, it is necessary to rotate and knock the bcd surfaces. Ideally, the buffer head 18 contacts the center of the first loading group b surface 31, the first loading group c surface 25, and the first loading group d surface 32 and the first bubble level 20 displays horizontal, and there is no need to continue adjusting the loading mechanism.

[0116] Specifically, the specific process of dynamically calibrating the six-dimensional force sensor using the above-mentioned dynamic calibration device is as follows:

[0117] S1. Calibrate Fx

[0118] Adjust the positions of the first vertical beam 7 and the second vertical beam 8 of the dynamic load loading device, the position of the mounting mechanism and the length of the retractable rod 15 in the dynamic load generating mechanism respectively, so that the buffer head 18 contacts the center of the first loading group a surface 24 and the first bubble level 20 displays level.

[0119] Manually pick up the piezoelectric impact force sensor 17 and release it. The dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, the swing angle increases evenly every 30 degrees. The voltage output value of the impact force sensor 17 in the dynamic load generating mechanism and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated are automatically recorded. This cycle is repeated three times and the recording is performed automatically.

[0120] Next, remove the clips used to fix the calibration base 12 and the sensor mounting platform 4, rotate the sensor calibration firmware 180 degrees clockwise, and then install the clips to fix it again. At this time, the buffer head 18 should contact the center of the first loading group b surface 31 and the first bubble level 20 should display horizontal, otherwise adjust it. Manually pick up the piezoelectric impact force sensor 17 and release it, and the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, it increases evenly every 30 degrees, and automatically records the voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. Repeat three times and automatically record to form the Fx dynamic calibration data set.

[0121] S2. Calibrate Fy

[0122] Remove the clips used to fix the calibration base 12 and the sensor mounting platform 4, rotate the sensor calibration firmware 90 degrees counterclockwise, and then install the clips to secure it again. At this time, the buffer head should contact the center of the first loading group c surface 25 and the first bubble level 20 should display level, otherwise make adjustments. By manually picking up the piezoelectric impact force sensor 17 and releasing it, the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, it increases evenly every 30 degrees, and automatically records the voltage output value of the impact force sensor 17 in the dynamic load generating mechanism and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. Repeat three times and record automatically.

[0123] Next, remove the clips used to fix the calibration base 12 and the sensor mounting platform 4, rotate the sensor calibration firmware 180 degrees clockwise, and then install the clips to secure it again. At this time, the buffer head 18 should contact the center of the first loading group c surface 25 and the first bubble level 20 should display level, otherwise make adjustments. Manually pick up the piezoelectric impact force sensor 17 and release it, and the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, it increases evenly every 30 degrees, and automatically records the voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. Repeat three times and automatically record to form the Fy dynamic calibration data set.

[0124] S3. Calibrate Mx:

[0125] Adjust the position of the right-angle mounting mechanism and the length of the telescopic rod 15 in the dynamic load generator until the buffer head contacts the center of the second loading group's surface a 26 and the first bubble level 20 indicates a level reading. Manually lift and release the piezoelectric impact force sensor 17, causing the dynamic load generator to swing about the bearing 16. The swing angle increases uniformly in 30-degree increments, starting from 0 degrees to 180 degrees. The voltage output of the piezoelectric impact force sensor 17 in the dynamic load generator and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated are automatically recorded. Repeat this cycle three times, with the recording process continuing.

[0126] Next, remove the clips used to fix the calibration base 12 and the sensor mounting platform 4, rotate the sensor calibration firmware 180 degrees clockwise, and then fix the clips again. At this time, the buffer head 18 contacts the center of the second loading group b surface 33 and the first bubble level 20 displays level, otherwise adjust. By manually picking up the piezoelectric impact force sensor 17 and releasing it, the dynamic load generating mechanism swings around the bearing 16, starting from 0 degrees and ending at 180 degrees, increasing evenly every 30 degrees, and automatically recording the voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. The cycle is repeated three times and the recording is automatic to form an Mx dynamic calibration data set.

[0127] S4. Calibrate My

[0128] Remove the clips used to fix the calibration base 12 and the sensor mounting platform 4, rotate the sensor calibration firmware 90 degrees counterclockwise, and then install the clips to fix it again. Adjust the position of the right-angle mounting mechanism and the length of the retractable rod 15 in the dynamic load generating device respectively, so that the buffer head 18 contacts the middle of the second loading group b surface 33 and the first bubble level 20 displays horizontal. By manually picking up the piezoelectric impact force sensor 17 and releasing it, the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, it increases evenly every 30 degrees, and automatically records the voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. Repeat three times and record automatically.

[0129] Next, remove the clips used to fix the calibration base 12 and the sensor mounting platform 4, rotate the sensor calibration firmware 180 degrees clockwise, and then install the clips to fix it again. At this time, the buffer head 18 contacts the center of the second loading group d surface 34 and the first bubble level 20 displays level, otherwise adjust it. By manually picking up the piezoelectric impact force sensor 17 and releasing it, the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, it increases evenly every 30 degrees, and automatically records the voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. The cycle is repeated three times and the records are automatically recorded to form the My dynamic calibration data set.

[0130] S5. Calibrate Mz

[0131] Adjust the positions of the first and second vertical beams 7 and 8 of the dynamic load-applying device, the right-angle mounting mechanism, and the length of the retractable rod 15 in the dynamic load-generating device so that the buffer head 18 contacts the center of the third loading group's surface a 28 and the first bubble level 20 indicates a level reading. Manually lift and release the piezoelectric impact force sensor 17, causing the dynamic load-generating mechanism to swing about the bearing 16. The swing angle increases uniformly every 30 degrees, from 0 to 180 degrees. The voltage output of the piezoelectric impact force sensor in the dynamic load-generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated are automatically recorded. Repeat this cycle three times, with automatic recording.

[0132] Next, adjust the positions of the first and second vertical beams 7 and 8 of the dynamic load loading device, the position of the right-angle mounting mechanism, and the length of the retractable rod 15 in the dynamic load generating device so that the buffer head 18 contacts the center of the third loading group b surface 29 and the first bubble level 20 indicates levelness. Manually lift and release the piezoelectric impact force sensor 17, and the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 180 degrees, the angle increases evenly every 30 degrees. The voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated are automatically recorded. This cycle repeats three times, with automatic recording, to form the Mz dynamic calibration data set.

[0133] S6. Calibrate Fz

[0134] Complete the installation of the dynamic load generating device and the right-angle mounting mechanism on the first vertical beam 7. Adjust the position of the first vertical beam 7 and the second vertical beam 8 of the dynamic load loading device, the position of the right-angle mounting mechanism, and the length of the retractable rod 15 in the dynamic load generating device respectively, so that the buffer head 18 contacts the middle part of the fourth loading group a surface 30 and the second bubble level 21 displays horizontal. By manually picking up the piezoelectric impact force sensor 17 and releasing it, the dynamic load generating mechanism swings around the bearing 16. Starting from 0 degrees and ending at 90 degrees, it increases evenly every 15 degrees, and automatically records the voltage output value of the piezoelectric impact force sensor 17 in the dynamic load generating device and the output voltage of each channel of the multi-dimensional force sensor to be dynamically calibrated. Repeat three times and automatically record to form the Fz dynamic calibration data set.

[0135] S7. Obtaining dynamic calibration results

[0136] The input data from the piezoelectric impact force sensor in the six directions (Fx, Fy, Fz, Mx, My, and Mz) form an input matrix. The output voltage values ​​from the multi-dimensional force sensor in the six directions (Fx, Fy, Fz, Mx, My, and Mz) form an output matrix. The dynamic model of the multi-dimensional force sensor is calculated using the formula. Calibration is complete.

[0137] In this specification, the terms "connect," "install," and "fix" should be understood broadly. For example, "connect" can refer to a fixed connection, a detachable connection, or an integral connection; it can refer to a direct connection or an indirect connection through an intermediary. Those skilled in the art will understand the specific meanings of these terms in this application based on the specific circumstances.

[0138] Throughout this specification, terms such as "one embodiment" or "some embodiments" mean that the specific features, structures, materials, or characteristics described in conjunction with that embodiment or example are included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

[0139] The above are merely preferred embodiments of the present application and are not intended to limit the present application. Those skilled in the art will readily appreciate that various modifications and variations are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A dynamic calibration device for a multi-dimensional force sensor, characterized in that: include: Calibration platform; sensor calibration firmware loaded on the calibration platform; a dynamic load generating mechanism carried on the calibration platform; and a dynamic load applying mechanism carried on the dynamic load generating mechanism; The calibration platform includes: a calibration platform surface; a calibration platform base arranged parallel to and below the calibration platform surface; and a plurality of support rods connected between the calibration platform surface and the calibration platform base; a sensor mounting platform is arranged on the calibration platform surface; The sensor calibration firmware includes: a calibration base mounted on the sensor mounting platform and a calibration cap disposed above the calibration base; a multi-dimensional force sensor is disposed between the calibration base and the calibration cap; the calibration cap is used to determine the dynamic load loading position and direction and transmit the dynamic load to the elastic body of the multi-dimensional force sensor; The dynamic load generating mechanism includes: a telescopic rod; a bearing mounted on one end of the telescopic rod; and an impact force sensor mounted on the other end of the telescopic rod; the axial direction of the telescopic rod and the force direction of the impact force sensor are perpendicular to each other; The dynamic load loading mechanism includes: a first bottom beam and a second bottom beam installed in parallel above the calibration platform; a first vertical beam slidably installed above the first bottom beam; a second vertical beam slidably installed above the second bottom beam; a cross beam connected between the top of the first vertical beam and the top of the second vertical beam; and a mounting mechanism slidably installed on the first vertical beam or the second vertical beam or the cross beam.

2. The device according to claim 1, characterized in that A vibration isolation pad is provided under the base of the calibration platform; Two rows of holes are provided on both sides of the edge of the calibration platform surface.

3. The device according to claim 2, characterized in that The calibration cap is provided with a raised mark; the raised mark is used to determine the installation direction of the multi-dimensional force sensor; when the calibration cap is installed with the multi-dimensional force sensor, its direction coincides with the detection direction of the multi-dimensional force sensor Fx; The calibration base and the calibration cap are both provided with screw holes, and the screw holes are used to fix and install the multi-dimensional force sensor; The calibration cap is provided with a plurality of loading positions, and each of the loading positions is divided into different loading point groups according to the dynamic calibration direction; The sensor mounting platform and the calibration base are both provided with a plurality of buckles; the buckles are used to ensure that the calibration base and the sensor mounting platform are relatively stationary during the dynamic calibration process; The clip is U-shaped; the shapes of the calibration base and the sensor mounting platform are corresponding to each other, and both include a mounting body and a plurality of positioning parts arranged along the outer circumference of the mounting body; when the calibration base and the positioning parts of the sensor mounting platform coincide with each other, the clip can be installed vertically to connect the calibration base and the sensor mounting platform together, and when subjected to impact excitation, the clip is used to ensure the relative stillness and stability of the calibration base and the sensor mounting platform.

4. The device according to claim 3, characterized in that The impact force sensor is provided with a buffer head in the force direction and a counterweight in the opposite direction of the force direction; The buffer head is made of any one of stainless steel, aluminum, nylon or rubber.

5. The device according to claim 4, characterized in that The mounting mechanism is arranged corresponding to the bearing; the mounting mechanism is mounted on the bearing.

6. The device according to claim 5, characterized in that The mounting mechanism includes: a first mounting plate, a second mounting plate, and a mounting portion; The first mounting plate is slidably mounted on the first vertical beam, the second vertical beam, or the horizontal beam; One end of the second mounting plate is vertically connected to the first mounting plate, and the other end is provided with a mounting portion; The bearing is mounted on the mounting portion.

7. The device according to claim 6, characterized in that The bearing is provided with a bubble level; the bubble level includes a first bubble level and a second bubble level; The bearing edge is provided with an angle scale; the angle scale is used to distinguish the dynamic load release height during dynamic calibration; the angle scale is arranged along the outer circumference of the bearing edge, and the angle scale includes a short scale arranged every fifteen degrees and a long scale arranged every thirty degrees.

8. The device according to claim 4, characterized in that The multi-dimensional force sensor is in the shape of a symmetrical cylinder or square column when viewed from above.

9. The device according to claim 4, characterized in that The impact force sensor is a piezoelectric impact force sensor.

10. A dynamic calibration method for a multi-dimensional force sensor, characterized in that: The method is implemented using the device according to any one of claims 5 to 9, and the method includes: (1) Adjust the position of the mounting mechanism and the length of the telescopic rod so that the buffer head contacts the center of the loading group to be calibrated and the bubble level indicator displays a horizontal position; (2) Move the piezoelectric impact force sensor to the corresponding position of the bearing and then release it. The dynamic load generating mechanism swings around the bearing to achieve the impact force calibration of the six-dimensional force sensor to be dynamically calibrated in all directions; (3) During the impact force calibration process, the voltage output value of the impact force sensor and the output voltage in each direction of the multi-dimensional force sensor to be dynamically calibrated are obtained to determine the dynamic calibration data set; (4) Based on the dynamic calibration data set, the input data of the impact force sensor in each direction is formed into an input matrix, and the output voltage values ​​of the multi-dimensional force sensor in each direction is formed into an output matrix. The dynamic model of the multi-dimensional force sensor is determined based on the input matrix and the output matrix to complete the calibration.

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