A six-dimensional force sensor calibration device

Abstract

The utility model discloses a six -dimensional force sensor calibration device relates to sensor calibration technical field, including six -dimensional force sensor, loading plate and fixed base, and loading plate contains the disc portion that six -dimensional force sensor top is in line with, and disc portion lateral wall extends along the diameter direction and forms the force beam that is cross -distribution of cross, and disc portion center is established space rectangular coordinate system, and along the length direction of cross -distribution of force beam is defined as X -axis, Y -axis respectively, and along the direction perpendicular to disc portion plane is defined as Z -axis, and X -axis corresponding two force beam end, and Y -axis corresponding one force beam end, and every end all is equipped with four lateral surface, and every end only selects two mutually perpendicular lateral surface as target force surface, and corresponding every target force surface, all are configured with forcing device. The utility model can realize six -dimensional force synchronous accurate loading, and promote calibration precision and efficiency.

Description

Technical Field

[0001] This utility model relates to the field of sensor calibration technology, specifically to a six-dimensional force sensor calibration device, which is particularly suitable for calibration scenarios that require simultaneous and accurate loading of six forces on a six-dimensional force sensor. It can be widely used in fields such as industrial robots where the measurement accuracy of six-dimensional force sensors is required. Background Technology

[0002] Six-dimensional force sensors can measure three force components (typically forces in the X, Y, and Z directions) and three torque components (torques about the X, Y, and Z axes) in space, and have wide applications in many fields such as industrial robots, aerospace, and medical equipment. However, due to factors such as manufacturing processes and material properties, six-dimensional force sensors exhibit inherent coupling characteristics (i.e., "crosstalk") in each dimension of the force / torque. For example, applying a force in the X direction alone may produce spurious outputs in the Y or Z direction, and applying a torque about the X axis alone may produce interference signals about the Y or Z axis. To ensure the measurement accuracy of six-dimensional force sensors, calibration is necessary. This calibration not only determines the accurate relationship between the sensor's input and output but also eliminates crosstalk between dimensions, achieving precise decoupling of the six-dimensional forces.

[0003] Existing six-dimensional force sensor calibration devices have some shortcomings:

[0004] 1. Some calibration devices have complex structures and cumbersome calibration processes, requiring multiple flipping and disassembly of the six-dimensional force sensor. This not only increases the difficulty of operation but also easily introduces a large amount of human error, resulting in low calibration accuracy. Some calibration devices (such as application number 202320256211.6) apply force by manually handling weights, which consumes a lot of manpower and has a limited calibration range. At the same time, they cannot deal with crosstalk problems and cannot meet the current decoupled calibration requirements of six-dimensional force sensors.

[0005] 2. Most devices can only achieve single-dimensional force / torque loading (e.g., calibrating the X-axis force first, then disassembling and adjusting the device to calibrate the Y-axis force): On the one hand, single loading cannot capture the coupling rules between dimensions and cannot provide data support for decoupling calculations. For example, when loading the X-axis force alone, the sensor's false output (crosstalk) in the Y-axis will be misjudged as the true output of the Y-axis force, resulting in a significant decrease in the measurement accuracy of the sensor under actual multi-dimensional force conditions after calibration. On the other hand, the calibration results of single loading deviate greatly from the actual working conditions, and crosstalk problems cannot be avoided, making it impossible to achieve six-dimensional force decoupling and failing to meet the requirements of high-precision application scenarios.

[0006] Therefore, developing a six-dimensional force sensor calibration device that is simple in structure, easy to operate, can achieve simultaneous and precise loading of six forces, thereby eliminating dimensional crosstalk, completing six-dimensional force decoupling, and has a fixed structure without redundancy and direct and efficient force transmission is of great practical significance for solving crosstalk problems, achieving precise decoupling, and improving the actual measurement accuracy of the sensor. Summary of the Invention

[0007] The purpose of this utility model is to provide a six-dimensional force sensor calibration device to solve the problems of existing calibration devices, such as cumbersome calibration steps, high manpower consumption, inability to simultaneously apply six forces resulting in low accuracy, and the tendency for crosstalk to occur when applying forces individually, making it impossible to achieve six-dimensional force decoupling. The core innovation lies in eliminating crosstalk and achieving precise decoupling of six-dimensional forces by simultaneously and accurately applying six forces, while improving calibration accuracy and adaptability to actual working conditions.

[0008] To achieve the above-mentioned objectives, the technical solution adopted by this utility model is as follows:

[0009] A six-dimensional force sensor calibration device includes a six-dimensional force sensor, a loading plate disposed on top of the six-dimensional force sensor, and a fixing base disposed on the bottom of the six-dimensional force sensor. The loading plate includes a disc portion that fits against the top of the six-dimensional force sensor. The sidewalls of the disc portion extend along the diameter direction to form cross-shaped force-bearing beams. A spatial rectangular coordinate system is established with the center of the disc portion as the origin. The X-axis and Y-axis are defined along the length direction of the cross-shaped force-bearing beams, and the Z-axis is defined along the direction perpendicular to the plane of the disc portion. Each end of the two force-bearing beams corresponding to the X-axis and one of the force-bearing beams corresponding to the Y-axis has four sides, and only two mutually perpendicular sides are selected from each end as target force-bearing surfaces. A force-applying device is configured for each target force-bearing surface, and the force-applying end of the force-applying device is connected to the corresponding target force-bearing surface to apply the calibration required force to the target force-bearing surface.

[0010] A further improvement of this invention is that each of the force-applying devices is fixedly installed on a calibration bench. There are six sets of force-applying devices. The six sets of force-applying devices are linked by a control system and can synchronously apply forces / torques in six dimensions to the loading plate. Through synchronous loading, complete corresponding data of six-dimensional forces and six-dimensional output signals of sensors can be collected in real time, avoiding the problem of not being able to capture crosstalk patterns when loading alone, and providing core data support for subsequent decoupling calculations.

[0011] A further improvement of this utility model is that the fixing base is fixedly connected to the calibration platform by bolts, and the disc part is provided with four screw holes arranged in an array. The disc part is connected to the top screw of the six-dimensional force sensor through the screw holes, so as to ensure the effective transmission of force between the loading plate and the six-dimensional force sensor.

[0012] A further improvement of this utility model is that the force application device is a servo linear motor integrating a high-precision force sensor. The force application direction of the force application device is perpendicular to the target force-bearing surface of the force-bearing beam. The servo linear motor can accurately control the magnitude of the applied force, ensuring that the calibration process data is accurate and reliable.

[0013] A further improvement of this utility model is that the disc portion of the loading plate and the load-bearing beam are integrally formed structures to improve the overall strength and rigidity of the loading plate, reduce deformation during the loading process, and ensure the accuracy of force transmission.

[0014] The beneficial effects of this utility model are:

[0015] 1. The calibration device of this utility model has a simple structure. By setting the target force surface and the force application device at a specific position on the loading plate, it is possible to conveniently apply multi-dimensional force and torque synchronously to the six-dimensional force sensor without repeatedly flipping and disassembling the six-dimensional force sensor, which greatly simplifies the calibration steps and reduces human error. At the same time, the fixed loading structure avoids the deviation of the force application position caused by disassembly and adjustment, ensuring the consistency of the coupling relationship data for each synchronous loading and improving the stability of decoupling calibration.

[0016] 2. This utility model uses a servo linear motor with an integrated high-precision force sensor as the force application device, which can accurately control the magnitude and direction of the applied force. During synchronous loading, the force value accuracy of the six force application devices can be monitored in real time, ensuring the accuracy of the six-dimensional input force and avoiding misjudgment of the coupling law due to force application error. This provides high-precision input data for subsequent decoupling calculations and comprehensively and accurately calibrates the decoupling performance of the six-dimensional force sensor.

[0017] 3. This utility model achieves synchronous and precise loading of force / torque in six dimensions through the linkage control of six sets of fixedly installed force-applying devices. It fundamentally solves the crosstalk problem and six-dimensional force decoupling challenge of existing devices when loading individually: Six-dimensional force sensors have inherent coupling characteristics (crosstalk) in each dimension of force / torque. Individual loading can only establish a single-dimensional input-output relationship, failing to capture the coupling pattern and thus preventing decoupling. However, this device, during synchronous loading, can collect input force data and corresponding sensor output signals in six dimensions in real time. Based on this complete data, a decoupling matrix is ​​constructed. This matrix corrects the crosstalk effects in each dimension, eliminating crosstalk between dimensions and ensuring that the calibrated sensor outputs independently and accurately in each dimension under multi-dimensional force conditions, truly achieving precise decoupling of six-dimensional force.

[0018] 4. The layout of the force application points of this utility model is simplified and the calibration dimensions are complete, taking into account both economy and scientificity. This device can realize the calibration of all six-dimensional parameters (X / Y / Z force and torque around X / Y / Z axes) of the six-dimensional force sensor by setting the force application device at the ends of the two force beams at both ends of the X-axis and the end of the force beam at one end of the Y-axis. There is no need to add a force application device at the other end of the Y-axis or at an additional position, which greatly simplifies the layout of the force application system. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the structure of this utility model.

[0020] Figure 2 A schematic diagram of a force-applying device installed on the force-bearing surface of a target at one end in this utility model.

[0021] In the diagram: 1. Six-dimensional force sensor; 2. Loading plate; 3. Fixing base; 4. Disc; 5. Force-bearing beam; 6. Target force-bearing surface; 7. Force-applying device; 8. Screw hole. Detailed Implementation

[0022] The technical solution of this utility model will be further described in detail below through specific embodiments and with reference to the accompanying drawings:

[0023] like Figure 1-2 As shown, a six-dimensional force sensor calibration device includes a six-dimensional force sensor 1, a loading plate 2 disposed on the top of the six-dimensional force sensor 1, and a fixing base 3 disposed on the bottom of the six-dimensional force sensor 1. The loading plate 2 includes a disk portion 4 that fits against the top of the six-dimensional force sensor 1. The sidewall of the disk portion 4 extends along the diameter direction to form force-bearing beams 5 distributed in a cross shape. A spatial rectangular coordinate system is established with the center of the disk portion 4 as the origin. The length directions of the cross-shaped force-bearing beams 5 are defined as the X-axis and Y-axis, respectively, and the direction perpendicular to the plane of the disk portion 4 is defined as the Z-axis. Each end of the two force-bearing beams 5 corresponding to the X-axis and one of the force-bearing beams 5 corresponding to the Y-axis has four sides, and only two mutually perpendicular sides of each end are selected as target force-bearing surfaces 6. A force-applying device 7 is provided for each target force-bearing surface 6. The force-applying end of the force-applying device 7 is connected to the corresponding target force-bearing surface 6 and is used to apply the calibration required force to the target force-bearing surface 6.

[0024] In this embodiment, each force-applying device 7 is fixedly installed on the calibration stand. There are six sets of force-applying devices 7. The six sets of force-applying devices 7 are linked together through the control system and can synchronously apply forces / torques in six dimensions to the loading plate 2.

[0025] In this embodiment, the fixed base 3 is fixedly connected to the calibration platform by bolts, and the disc part 4 is provided with four screw holes 8 arranged in an array. The disc part 4 is connected to the top screw of the six-dimensional force sensor 1 through the screw holes 8 to ensure the effective transmission of force between the loading plate 2 and the six-dimensional force sensor 1.

[0026] In this embodiment, the force application device 7 is a servo linear motor with an integrated high-precision force sensor. The force application direction of the force application device 7 is perpendicular to the target force-bearing surface 6 of the force-bearing beam 5. The servo linear motor can accurately control the magnitude of the applied force, ensuring that the calibration process data is accurate and reliable.

[0027] In this embodiment, the disk portion 4 of the loading plate 2 and the load-bearing beam 5 are integrally formed structures to improve the overall strength and rigidity of the loading plate 2, reduce the deformation generated during the loading process, and ensure the accuracy of force transmission.

[0028] Installation process:

[0029] First, connect the loading plate 2 to the top screw of the six-dimensional force sensor 1 through the four screw holes 8 of the disc part 4, ensuring there is no gap between the loading plate 2 and the sensor. Then, connect the six-dimensional force sensor 1 to the fixing base 3. At this time, the six sets of force application devices 7 on the calibration stand are installed and fixed. Move the fixing base 3 to a suitable position on the calibration stand and fix it. Then, rigidly connect the force application end of each set of force application devices 7 to the target force-bearing surface 6 of the loading plate 2 through the connector. Connect the force sensor signals of the six sets of force application devices 7 to the unified control system, calibrate the force value of each force application device 7, and set the synchronous loading logic of the six-dimensional force / torque to ensure the accuracy of the calibration process.

[0030] Calibration process:

[0031] 1. Parameter setting: Based on the range and decoupling requirements of the six-dimensional force sensor, set multiple sets of target six-dimensional force / torque parameter combinations for synchronous loading (e.g., combination 1: Fx = 50N, Fy = 30N, Fz = 100N, Mx = 10N·m, My = 8N·m, Mz = 15N·m; combination 2: Fx = -40N, Fy = 20N, Fz = 80N, Mx = -8N·m, My = 12N·m, Mz = 10N·m, etc.).

[0032] 2. Synchronous loading: Based on the target force value and torque of the six-dimensional force sensor, the corresponding force value of each force application device is calculated according to the formula, and the devices operate synchronously according to the set parameters. The six force application devices simultaneously apply the set force to the corresponding target force surface, and the force data of the force application devices and the output signal of the six-dimensional force sensor 1 are collected in real time to establish the correspondence between input and output.

[0033] 3. Multiple sets of data acquisition: According to the calibration requirements, repeat steps 1-2, adjust different combinations of six-dimensional force / torque parameters, and acquire multiple sets of calibration data to ensure coverage of the sensor range.

[0034] 4. Calibration complete: After all data acquisition is completed, the control system stops applying force and saves the calibration data for subsequent sensor accuracy calibration. The entire process does not require disassembly or adjustment of the sensor position.

[0035] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention without departing from the principles and spirit of the present invention. Any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention shall still fall within the scope of the technical solution of the present invention.

Claims

1. A six-dimensional force sensor calibration device, comprising a six-dimensional force sensor, a loading plate arranged on the top of the six-dimensional force sensor, and a fixing base arranged on the bottom of the six-dimensional force sensor, characterized in that, The loading plate includes a disk portion that fits against the top of the six-dimensional force sensor. The sidewalls of the disk portion extend along the diameter direction to form cross-shaped force beams. A spatial rectangular coordinate system is established with the center of the disk portion as the origin. The X-axis and Y-axis are defined along the length direction of the cross-shaped force beams, and the Z-axis is defined along the direction perpendicular to the plane of the disk portion. Each end of the two force beams corresponding to the X-axis and one of the force beams corresponding to the Y-axis has four sides, and only two mutually perpendicular sides of each end are selected as target force surfaces. A force application device is provided for each target force surface. The force application end of the force application device is connected to the corresponding target force surface to apply the calibration required force to the target force surface.

2. The six-dimensional force sensor calibration device according to claim 1, characterized in that, All of the force-applying devices are fixedly installed on the calibration stand.

3. The six-dimensional force sensor calibration device according to claim 1, characterized in that, The mounting base is fixedly connected to the calibration platform by bolts. The disc has four screw holes arranged in an array, and the disc is connected to the top screw of the six-dimensional force sensor through the screw holes.

4. The six-dimensional force sensor calibration device according to claim 1, characterized in that, The force application device is a servo linear motor integrating a high-precision force sensor, and the force application direction of the force application device is perpendicular to the target force-bearing surface of the force-bearing beam.

5. A six-dimensional force sensor calibration device according to claim 1, characterized in that, The disc portion of the loading plate and the load-bearing beam are integrally formed structures.

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