A portable, integrated six-dimensional force measuring board

Abstract

This utility model discloses an integrated six-dimensional portable force measuring plate, including an elastomer and a protective assembly disposed outside the elastomer. The assembly includes a hub, a force-bearing platform, and multiple strain beams. The force-bearing platform is located in the center of the hub, and the hub and force-bearing platform are connected by multiple strain beams. Multiple strain gauges are attached to different positions on the strain beams. A through hole is formed in the center of the force-bearing platform, and a bridge plate for forming a Wheatstone bridge and a data acquisition board for collecting and converting the output signals of the elastomer are disposed within the through hole. Multiple wires are led out from the strain gauges and soldered to the bridge plate to form six Wheatstone bridges, which are used to detect forces and moments in three directions, denoted as Fx, Fy, Fz, Mx, My, and Mz. Advantages: The integrated force measuring plate eliminates the need for multiple sensor splicing; multiple beams can work together to balance the force and compensate for each other, reducing the influence of off-center loading on the measurement results; multiple force measuring plates can be spliced ​​together for use.

Description

Technical Field

[0001] This utility model relates to an integrated six-dimensional force portable force measuring plate, belonging to the field of sensor measurement technology. Background Technology

[0002] With the rapid development of science and technology, in order to conduct in-depth research on the mechanical principles of human movement, researchers need to accurately measure the force exerted by the human body on the ground during movement. The emergence of force measuring plates makes it possible to obtain this data, which helps to establish more accurate human dynamics models.

[0003] Similarly, in rehabilitation training, force plates can monitor the recovery of a patient's limb strength in real time, providing quantitative data for rehabilitation therapists to adjust training programs and improve the effectiveness of rehabilitation training. However, most force plates currently on the market are composed of multiple sensors assembled together, which suffers from problems such as large errors, low accuracy, and complex assembly. They cannot meet the requirements for use in human biomechanical testing systems.

[0004] Chinese patent application number 201721020934.7 discloses an ultra-thin weighing force plate sensor, including a main plate and a cantilevered thin-film sensor elastomer integrated with the main plate. The plate sensor has multiple cantilevered thin-film sensor elastomers distributed around the periphery of the main plate. This invention integrates the sensor with the structural components, rather than assembling them, thus minimizing the overall height and facilitating manufacturing and installation. The sensor has mounting holes, allowing customers to directly install support brackets for immediate use.

[0005] The force plate in the comparative document is composed of multiple thin-film sensors. If the installation position of the multiple sensors is misaligned, it will lead to large errors in the measurement results, low accuracy, and complex assembly. Therefore, a force plate with a simple elastomer structure, easy to process, and high accuracy and sensitivity is needed. Utility Model Content

[0006] The technical problem to be solved by this utility model is that the existing force measuring plate is composed of multiple thin-film sensors. If the installation position of the multiple sensors is deviated, it will lead to a large error in the measurement result, low accuracy, and complicated assembly.

[0007] To address the aforementioned technical problems, an integrated six-dimensional portable force measuring plate is proposed; this is achieved through the following technical solution: The force measuring plate is placed on the ground and includes an elastomer and a protective assembly placed outside the elastomer. The elastomer is generally square and includes a hub, a force-bearing platform, and multiple strain beams. The force-bearing platform is located in the middle of the hub. Multiple strain beams connect the hub and the force-bearing platform. Multiple strain gauges are attached to different positions on the strain beams. A through hole is opened in the middle of the force-bearing platform. A bridge plate for forming a Wheatstone bridge and a data acquisition board for collecting and converting the output signals of the elastomer are installed in the through hole. Multiple wires are led out from the strain gauges and welded to the bridge plate to form six Wheatstone bridges, which are used to detect forces and moments in three directions, denoted as Fx, Fy, Fz, Mx, My, and Mz. The protective assembly includes an upper cover plate, a lower cover plate, a top cover plate, and a back plate. The upper and lower cover plates are connected to the upper and lower surfaces of the hub, respectively, and both cover the strain beams. The top cover plate and the back plate are located on the upper and lower surfaces of the force-bearing platform, respectively, and both cover the through hole in the middle of the force-bearing platform.

[0008] This utility model's force measuring plate uses only one elastomer, making it easy to install. Furthermore, in human biomechanics testing systems requiring eccentric loading, the integrated force measuring plate avoids the problem of uneven force distribution on a single sensor leading to overall output distortion when multiple sensors are spliced ​​together and subjected to eccentric loading. Composed of multiple strain beams, one end of each beam is connected to the force platform, and the other end to the hub. Compared to the traditional four-beam structure, it can withstand forces from multiple directions. When the point of force application shifts, multiple beams can work together to balance the force and compensate for each other, reducing the impact of eccentric loading on the measurement results. Therefore, it has stronger resistance to eccentric loading. The force platform is installed in the center of the hub, and the bridge plate and data acquisition plate are located within the through-hole in the center of the force platform, making the entire force measuring plate lighter, smaller, and easier to carry.

[0009] In a preferred embodiment of the present invention, the elastomer has a square cross-section, and its shape is specifically designed for the force measuring plate, so that it can be used as a force measuring plate on its own without the need for assembly.

[0010] In a preferred embodiment of the present invention, the protective component further includes a top plate, which is disposed on the top cover plate and covers the top cover plate, the upper cover plate, and the entire elastomer, thereby protecting the entire elastomer.

[0011] In a preferred embodiment of the present invention, two wiring channels are provided on the stress-bearing platform corresponding to each strain beam. The wires connecting the strain gauge and the bridge plate pass through the wiring channels, making the wiring inside the elastic body neat and forming a Wheatstone bridge, thus avoiding the wiring chaos from affecting the performance of the elastic body.

[0012] In a preferred embodiment of the present invention, a connecting groove is provided on the side wall of the hub for each strain beam. One end of the strain beam is connected to the inside of the connecting groove, and the other end of the strain beam is connected to the force-bearing platform. The connection stiffness of the strain beam is weakened, and the sensitivity of the sensor is increased.

[0013] In a preferred embodiment of the present invention, the strain beam is a T-shaped column, comprising a horizontal beam and a vertical beam. Both the horizontal beam and the vertical beam have square cross-sections. The horizontal beam is set in a connecting groove, and one end of the vertical beam is connected to the side of the horizontal beam. The other end of the vertical beam is connected to the force-bearing platform. This reduces the connection area between the strain beam and the hub, weakens the connection stiffness of the strain beam, and increases the deformation of the strain beam.

[0014] In a preferred embodiment of the present invention, eight strain beams are arranged between the hub and the load-bearing platform, and a total of 44 strain gauges are arranged on the eight strain beams. Compared with the traditional four-beam structure, it can withstand the force from multiple directions. When the point of application of the force is offset, the multiple beams can work together to balance the force and compensate for each other, reducing the impact of off-center load on the measurement results.

[0015] In a preferred embodiment of the present invention, a foot is provided on the lower surface of the wheel hub to support the entire force measuring plate.

[0016] In a preferred embodiment of the present invention, the data acquisition board is provided with a first connector for connecting the power supply line, a second connector for connecting the series power line, and a third connector for connecting the signal transmission line. The second connector for connecting the series power line allows multiple force plates to be used simultaneously.

[0017] In the preferred embodiment of the present invention, the six Wheatstone bridges form a full-bridge circuit, which improves the precision of the detection results.

[0018] The advantages of this utility model compared with the prior art are: 1. The force measuring plate of this utility model uses only one elastic body, which is convenient for installation. In addition, the human body biomechanics testing system requires eccentric loading. The integral force measuring plate avoids the problem of uneven force on a certain sensor when multiple sensors are spliced ​​and eccentric loading is applied, which leads to the distortion of the overall output. The human body biomechanics testing system has high requirements for the accuracy of the force measuring plate. Compared with the force measuring plate spliced ​​with multiple sensors, the integral force measuring plate does not require the installation and cooperation of multiple sensors, avoids the influence of splicing gaps or deformation of connecting parts on the measurement, and reduces mechanical installation errors. 2. The force measuring plate of this utility model is an integral force measuring plate, which does not require splicing multiple sensors, has better integrity, higher stiffness and natural frequency, faster dynamic response and higher sensitivity; 3. The force measuring plate of this utility model has a hollow slot in the middle of the force-bearing platform, and the bridge plate and data acquisition plate on the back plate are set in the hollow slot in the middle of the force-bearing platform, making the entire force measuring plate lighter, smaller and easier to carry. 4. The elastic body of the force measuring plate of this utility model includes multiple strain beams. One end of the strain beam is connected to the force table and the other end is connected to the hub. Compared with the traditional 4-beam structure, it can withstand the force from multiple directions. When the point of application of the force is offset, the multiple beams can work together to balance the force and compensate each other, reducing the influence of off-center load on the measurement results. Therefore, it has a stronger resistance to off-center load. 5. The force measuring plate of this utility model is equipped with three flight inserts, and a synchronization line is reserved in the flight inserts to facilitate the splicing of multiple force measuring plates and the synchronous acquisition and use of multiple force measuring plates. Attached Figure Description

[0019] Figure 1 The figure shown is an exploded structural diagram of an integral six-dimensional portable force measuring plate according to this utility model. Figure 2 The figure shown is a three-dimensional structural diagram of an integral six-dimensional portable force measuring plate according to this utility model. Figure 3 The diagram shown is a schematic diagram of the internal structure of the top plate of the integrated six-dimensional force portable force measuring plate of this utility model. Figure 4 The diagram shown is a schematic diagram of the back structure of an integrated six-dimensional portable force measuring plate according to this utility model. Figure 5 The figure shown is a schematic diagram of the elastic body structure of an integral six-dimensional portable force measuring plate of this utility model. Figure 6 The figure shown is a top view of the elastic body of an integral six-dimensional portable force measuring plate according to this utility model; Figure 7 The diagram shown is a schematic of the installation position of the elastomer resistor in an integral six-dimensional portable force measuring plate according to this utility model. Figure 8 The image shown is an integrated six-dimensional portable force measuring plate according to this utility model. Figure 7 Cross-sectional view of AA; Figure 9 The image shown is an integrated six-dimensional portable force measuring plate according to this utility model. Figure 7 Cross-sectional view of BB; Figure 10 The image shown is an integrated six-dimensional portable force measuring plate according to this utility model. Figure 7 Cross-sectional view of CC; Figure 11 The image shown is an integrated six-dimensional portable force measuring plate according to this utility model. Figure 7 Cross-sectional view of DD; Figure 12 The diagram shown is a Wheatstone bridge diagram of an integrated six-dimensional force portable force measuring plate according to this utility model.

[0020] Explanation of reference numerals in the attached drawings: 1. First strain beam; 2. Second strain beam; 3. Third strain beam; 4. Fourth strain beam; 5. Fifth strain beam; 6. Sixth strain beam; 7. Seventh strain beam; 8. Eighth strain beam; 9. Top plate; 10. Top cover plate; 11. Upper cover plate; 12. Bridge plate; 13. Data acquisition board; 14. Elastomer; 15. Back plate; 16. Lower cover plate; 17. Foot; 18. Hub; 19. Force-bearing platform; 20. Cable tray; 21. Through hole; 22. Stepped groove; 23. Connecting groove; 24. Aircraft connector; 25. Aircraft connector; 26. Second aircraft connector; 27. Third aircraft connector. Detailed Implementation

[0021] The following will refer to the appendix in the embodiments of this utility model. Figures 1-12 The technical solutions in the embodiments of this utility model will be described in detail below. Example

[0022] like Figures 1-6 As shown, in this embodiment, the force measuring plate is placed on the ground, the top plate 9 is defined as the upper end of the force measuring plate, the foot 17 is defined as the lower end of the force measuring plate, and a rectangular coordinate system is established with the center point of the elastic body 14 as the origin.

[0023] An integrated six-dimensional force measuring plate includes an elastomer 14 and a protective component disposed outside the elastomer 14.

[0024] like Figure 1 and Figure 2 As shown, the entire elastic body 14 is a square plate with a square cross-section, including a hub 18, a force-bearing platform 19 and multiple strain beams. This makes a single square plate elastic body 14 a force-measuring plate, eliminating the need for multiple elastic bodies 14 to be spliced ​​together. This avoids the problem of uneven force on a single sensor causing overall output distortion when multiple sensors are spliced ​​together and eccentrically loaded.

[0025] like Figure 5 As shown, this embodiment includes a total of 8 strain beams. The hub 18 is a ring structure with a square cross-section. A square cavity is opened in the middle of the hub 18. The force-bearing platform 19 is installed inside the square cavity through the 8 strain beams. The elastic body 14 includes 8 strain beams. Compared with the traditional 4-beam structure, it can withstand the force from multiple directions. When the point of application of the force is offset, multiple beams can work together to balance the force and compensate for each other, reducing the impact of off-center load on the measurement results.

[0026] like Figure 5As shown, the four inner sides of the hub 18 are provided with two connecting grooves 23 respectively. A strain beam is welded in each connecting groove 23. The strain beam is a T-shaped column, including an integrally set horizontal beam and a vertical beam. The two ends of the horizontal beam are welded to the side wall of the connecting groove 23, and one end of the vertical beam is welded to the middle of the horizontal beam. The other end of the vertical beam is welded to the force-bearing platform 19. By setting the connecting grooves 23 on the hub 18 to connect the strain beam, the connection area between the strain beam and the hub 18 is reduced, the connection stiffness of the strain beam is weakened, and the deformation under stress is more sensitive.

[0027] like Figures 5-7 As shown, both the horizontal and vertical beams are cuboids. A total of 44 strain gauges are attached to different positions on the vertical beams of the eight strain beams, forming six Wheatstone bridges, which are used to detect forces and moments in three directions, denoted as Fx, Fy, Fz, Mx, My, and Mz. The eight strain beams can withstand forces from multiple directions. When the point of application of the force is offset, the multiple beams can work together to balance the force and compensate for each other, reducing the influence of off-center load on the measurement results. Therefore, it has a stronger resistance to off-center load, and the 44 strain gauges can more accurately detect the deformation of the strain beams, making the detection results of the entire elastic body 14 more accurate.

[0028] like Figure 5 As shown, the cross-section of the force-bearing platform 19 is square, and a through hole 21 is opened in the middle of the force-bearing platform 19. Two wiring grooves 20 are opened on the force-bearing platform 19 corresponding to each strain beam. The wires connecting the strain gauge and the bridge plate 12 pass through the wiring grooves 20.

[0029] like Figure 4 and Figure 5 As shown, a square cavity is opened in the middle of the hub 18 to install the strain beam and the force platform 19. A through hole 21 is opened in the middle of the force platform 19. A stepped groove 22 is opened in the inner ring of the force platform 19. The back plate 15 is fixedly connected to the stepped groove 22 of the force platform 19 by screws, so that the back plate 15 covers the through hole 21. The bridge plate 12 and the data acquisition plate 13 in the through hole 21 are fixed to the back plate 15 by copper pillars, so that the elastomer 14 is small in size and easy to carry. In this embodiment, the size of the elastomer 14 is 400*400*30mm.

[0030] like Figure 4 As shown, the data acquisition board 13 is equipped with a first connector 24 for connecting the power supply line, a second connector 25 for connecting the series power supply line, and a third connector 26 for transmitting the output signal of the Wheatstone bridge. The first connector 24 and the second connector 25 have pre-synchronization lines. The first connector 24 is connected to the power supply line of the entire force measuring board. The second connector 25 is used to connect other force measuring boards in series, so that multiple force measuring boards can use the third connector 26 synchronously. The third connector 26 is used to connect the signal line for transmitting the output signal of the Wheatstone bridge.

[0031] The first connector 24, the second connector 25, and the third connector 26 pass through the back panel 15 for easy wiring. When multiple force measuring plates need to be connected, the first connector 24 and the second connector 25 can be connected in one direction and out the other. The first connector 24 connects to the previous force measuring plate, and the second connector 25 connects to the next force measuring plate. Through the synchronization line reserved inside the first connector 24 and the second connector 25, multiple force measuring plates can achieve synchronous data acquisition, thus enabling multiple force measuring plates to be connected and operated.

[0032] The 44 strain gauges attached to the strain beam are connected to the bridge plate 12 via wires to form a Wheatstone bridge circuit. The bridge plate 12 is connected to the data acquisition board 13 via leads. The data acquisition board 13 collects the analog signals output by the Wheatstone bridge and converts them into digital signals for output, thereby obtaining the deformation data of the elastic body 14.

[0033] like Figures 1-4 As shown, the protective assembly includes a top plate 9, a top cover plate 10, a back plate 15, an upper cover plate 11, and a lower cover plate 16. The upper cover plate 11 and the lower cover plate 16 are both U-shaped plates, and the upper cover plate 11 and the lower cover plate 16 are respectively disposed on the upper surface and the lower surface of the elastomer 14.

[0034] like Figure 3 and Figure 4 As shown, the outer rings of the upper cover plate 11 and the lower cover plate 16 are connected to the upper and lower surfaces of the hub 18 by screws, respectively. Both the upper cover plate 11 and the lower cover plate 16 cover eight strain beams, ensuring that the upper cover plate 11 and the lower cover plate 16 can protect the eight strain beams.

[0035] like Figure 3 and Figure 4 As shown, the top cover plate 10 is fixedly connected to the upper surface of the force-bearing platform 19 by screws and covers the through hole 21 in the middle of the force-bearing platform 19. The back plate 15 is fixedly connected to the lower surface of the force-bearing platform 19 by screws and covers the through hole 21 in the middle of the force-bearing platform 19. The top plate 9 is fixedly connected to the upper surface of the force-bearing platform 19 by screws and covers the top cover plate 10, the upper cover plate 11 and the entire elastic body 14. The top cover plate 10 protects the force-bearing platform 19 and the back plate 15, and the top plate 9 protects the entire elastic body 14.

[0036] like Figure 2 As shown, in this embodiment, the top plate 9 is made of a 400*400*5mm carbon fiber plate. Eight M8 screws are used to install the top plate 9 on the upper surface of the elastomer 14. The top plate 9 covers the top cover plate 10 and the upper cover plate 11. The top plate 9, the top cover plate 10, and the upper cover plate 11 together serve as the load-bearing plate of the force measuring plate. In this embodiment, the force of the foot of the moving body such as the athlete or robot is directly applied to the top plate 9. The top plate 9 made of carbon fiber plate has the characteristics of high rigidity, high strength, and light weight, which makes the entire force measuring plate lighter and easier to carry.

[0037] like Figure 2 As shown, each of the four corners of the lower surface of the hub 18 is fixedly connected with a foot 17 by screws to support the entire force plate, and the height of the foot 17 is adjustable.

[0038] like Figure 6 and Figure 7 As shown, in this embodiment, the eight strain beams are respectively represented as: first strain beam 1, second strain beam 2, third strain beam 3, fourth strain beam 4, fifth strain beam 5, sixth strain beam 6, seventh strain beam 7 and eighth strain beam 8, and the 44 strain gauges are represented as R1~R44.

[0039] like Figures 7-11 As shown, the positions of the 44 strain gauges are as follows: like Figure 6 As shown, in this embodiment, the first strain beam 1 and the second strain beam 2 are installed on the same side of the force-bearing platform 19, the third strain beam 3 and the fourth strain beam 4 are installed on the same side of the force-bearing platform 19, the fifth strain beam 5 and the sixth strain beam 6 are installed on the same side of the force-bearing platform 19, and the seventh strain beam 7 and the eighth strain beam 8 are installed on the same side of the force-bearing platform 19. The first strain beam 1 and the second strain beam 2, the fifth strain beam 5 and the sixth strain beam 6 are symmetrical about the X-axis, and the third strain beam 3 and the fourth strain beam 4 are symmetrical about the Y-axis with respect to the seventh strain beam 7 and the eighth strain beam 8.

[0040] like Figures 7-11 As shown, strain gauges R13 and R14 are attached to the left and right sides of the first strain beam 1, which are perpendicular to the force-bearing surface of the force-bearing platform 19. R13 and R14 are symmetrically arranged about the length of the strain beam. R13 is located on the side of the first strain beam 1 near the second strain beam 2. The center of R13 is 3.2 mm away from the outer wall of the force-bearing platform 19 and 8 mm away from the upper surface of the first strain beam 1. R14 is located on the other side of the first strain beam 1, corresponding to R13. R1 and R30 are provided on the upper surface of the first strain beam 1. R1 is located near the hub 18. The center of R1 is 11 mm away from the outer wall of the force-bearing platform 19. R30 is located near the force-bearing platform 19. The center of R30 is 4.2 mm away from the outer wall of the force-bearing platform 19. R29 and R2 are provided on the lower surface of the first strain beam 1. R29 and R30 are arranged vertically corresponding to each other. R1 and R2 are arranged vertically corresponding to each other.

[0041] Strain gauges R11 and R12 are attached to the left and right sides of the second strain beam 2, which are perpendicular to the force-bearing surface of the force-bearing platform 19. R11 and R12 are symmetrically arranged about the length of the strain beam. The center of R11 is 3.2 mm away from the outer wall of the force-bearing platform 19, and the center of R11 is 8 mm away from the upper surface of the second strain beam 2. Strain gauges R32 and R37 are arranged on the upper surface of the second strain beam 2. R37 is located near the hub 18, and the center of R37 is 11 mm away from the outer wall of the force-bearing platform 19. R32 is located near the force-bearing platform 19, and the center of R32 is 4.2 mm away from the outer wall of the force-bearing platform 19. Strain gauges R31 and R38 are arranged on the lower surface of the second strain beam 2. R37 and R38 are arranged vertically, and R31 and R32 are arranged vertically.

[0042] On the left and right sides of the third strain beam 3, which are perpendicular to the force-bearing surface of the force-bearing platform 19, there are strain gauges R20 and R19 respectively. R20 and R19 are symmetrically arranged about the length of the strain beam. The center of R19 is 3.2 mm away from the outer wall of the force-bearing platform 19 and 8 mm away from the upper surface of the third strain beam 3. R28 and R5 are arranged on the upper surface of the third strain beam 3. R5 is located near the hub 18 and its center is 11 mm away from the outer wall of the force-bearing platform 19. R28 is located near the force-bearing platform 19 and its center is 4.2 mm away from the outer wall of the force-bearing platform 19. R27 and R6 are arranged on the lower surface of the third strain beam 3. R27 and R28 are arranged vertically correspondingly, and R6 and R5 are arranged vertically correspondingly.

[0043] The upper surface of the fourth strain beam 4 is provided with R24 and R41, where R41 is located near the hub 18 and the center of R41 is 11 mm away from the outer wall of the force platform 19. R24 is located near the force platform 19 and the center of R24 is 4.2 mm away from the outer wall of the force platform 19. The lower surface of the fourth strain beam 4 is provided with R23 and R42, where R23 and R24 are arranged vertically correspondingly, and R42 and R41 are arranged vertically correspondingly.

[0044] Strain gauges R15 and R16 are attached to the left and right sides of the fifth strain beam 5, which are perpendicular to the force-bearing surface of the force-bearing platform 19. R15 and R16 are symmetrically arranged about the length of the strain beam. The center of R15 is 3.2 mm away from the outer wall of the force-bearing platform 19 and 8 mm away from the upper surface of the fifth strain beam 5. R3 and R36 are arranged on the upper surface of the fifth strain beam 5. R3 is located near the hub 18 and its center is 11 mm away from the outer wall of the force-bearing platform 19. R36 is located near the force-bearing platform 19 and its center is 4.2 mm away from the outer wall of the force-bearing platform 19. R35 and R4 are arranged on the lower surface of the fifth strain beam 5. R35 and R36 are arranged vertically corresponding to each other, and R4 and R3 are arranged vertically corresponding to each other.

[0045] Strain gauges R10 and R9 are attached to the left and right sides of the sixth strain beam 6, which are perpendicular to the force-bearing surface of the force-bearing platform 19. R10 and R9 are symmetrically arranged about the length of the strain beam. The center of R10 is 3.2 mm away from the outer wall of the force-bearing platform 19 and 8 mm away from the upper surface of the sixth strain beam 6. R39 and R34 are arranged on the upper surface of the sixth strain beam 6. R39 is located near the hub 18 and its center is 11 mm away from the outer wall of the force-bearing platform 19. R34 is located near the force-bearing platform 19 and its center is 11 mm away from the outer wall of the force-bearing platform 19. R33 and R40 are arranged on the lower surface of the sixth strain beam 6. R33 and R34 are arranged vertically, and R40 and R39 are arranged vertically.

[0046] Strain gauges R18 and R17 are attached to the left and right sides of the seventh strain beam 7, which are perpendicular to the force-bearing surface of the force-bearing platform 19. R18 and R17 are symmetrically arranged about the length of the strain beam. The center of R17 is 3.2 mm away from the outer wall of the force-bearing platform 19 and 8 mm away from the upper surface of the seventh strain beam 7. R7 and R26 are arranged on the upper surface of the seventh strain beam 7. R7 is located near the hub 18 and its center is 11 mm away from the outer wall of the force-bearing platform 19. R26 is located near the force-bearing platform 19. R8 and R25 are arranged on the lower surface of the seventh strain beam 7. R8 and R7 are arranged vertically, and R25 and R26 are arranged vertically.

[0047] The upper surface of the eighth strain beam 8 is provided with R43 and R22. R43 is located near the hub 18, and the center of R43 is 11 mm away from the outer wall of the force platform 19. R22 is located near the force platform 19, and the center of R22 is 4.2 mm away from the outer wall of the force platform 19. The lower surface of the eighth strain beam 8 is provided with R44 and R21. R44 is arranged vertically to R43, and R21 is arranged vertically to R22.

[0048] like Figure 12As shown, four strain gauges (R13, R14, R15, and R16) on the left and right sides of the first strain beam 1 and the fifth strain beam 5 form a Wheatstone bridge for measuring Fx via a bridge assembly plate 12. Four strain gauges (R17, R18, R19, and R20) are attached to the two sides of the third strain beam 3 and the seventh strain beam 7 perpendicular to the force-bearing surface of the force-bearing platform 19. These four strain gauges form a Wheatstone bridge for measuring Fy via a bridge assembly plate 12. (The text repeats itself here, so the translation only includes the first and fifth strain beams.) Strain gauges, a total of 16, are located near the center of the upper and lower surfaces of strain beams 2, 3, 4, 5, 6, 7, and 8, which are parallel to the stress surface of the stress platform 19. These gauges are labeled R21, R22, R23, R24, R25, R26, R27, R28, R29, R30, R31, R32, R33, R34, R35, and R36. These gauges are connected by 12 sets of bridge plates. A Wheatstone bridge for measuring Fz is constructed. Eight strain gauges, R1, R2, R3, R4, R37, R38, R39, and R40, are located near the hub 18 on the upper and lower surfaces of the first strain beam 1, second strain beam 2, fifth strain beam 5, and sixth strain beam 6, parallel to the force-bearing surface of the force-bearing platform 19. These gauges are connected by a bridge assembly plate 12 to form a Wheatstone bridge for testing Mx. The strain gauges on the third strain beam 3, fourth strain beam 4, seventh strain beam 7, and eighth strain beam 8 are also connected. Eight strain gauges, R5, R6, R7, R8, R41, R42, R43, and R44, located on the upper and lower surfaces parallel to the force-bearing surface of the force-bearing platform 19 and near the hub 18, form a Wheatstone bridge for testing My via a bridge plate 12. Four strain gauges, R9, R10, R11, and R12, located on the two sides of the second strain beam 2 and the sixth strain beam 6 perpendicular to the force-bearing surface of the force-bearing platform 19, form a Wheatstone bridge for testing Mz via a bridge plate 12.

[0049] This embodiment uses 44 strain gauges to detect the force value of the force platform 19, which improves the accuracy of the entire elastic body 14. While detecting the force received by the force measuring plate, the sensitivity of the entire force measuring plate can also be tested based on the detection data of the strain gauges, ensuring that the force measuring plate can be used normally.

[0050] The sensitivity test of the integrated six-dimensional portable force measuring plate in Example 1 was performed. The specific process of strength analysis of the elastomer using ANSYS Workbench is as follows: As mentioned earlier, full-scale loading is applied individually in six directions: Fx, Fy, Fz, Mx, My, and Mz. The intensity and output sensitivity of full-scale loading in each direction are calculated. When a load of Fx = 2500 N is applied, the first strain beam 1, the second strain beam 2, the fifth strain beam 5, and the sixth strain beam 6 experience bending strain. Strain gauges R13 and R16 experience tensile strain, and strain gauges R14 and R15 experience compressive strain. The composition is as follows: Figure 4 Bridge 4 in the diagram, calculated using ANSYS Workbench, has the strain measured in R13 as follows: The dependent variable measured by R14 is The dependent variable measured by R15 is The dependent variable measured by R16 is ,but:

[0051] —This indicates the output voltage value in the Fx direction when Fx is fully loaded; — This represents the sensitivity coefficient of the strain gauge. In calculations, the average value is usually taken, with k=2. —This represents the strain measured in the R13 patch area of ​​the strain gauge; —This represents the strain measured in the R14 patch area of ​​the strain gauge; —This represents the strain measured in the R15 patch area of ​​the strain gauge; —This represents the strain measured in the R16 patch area of ​​the strain gauge; —This represents the excitation voltage of the bridge circuit, which is taken here. .

[0052] ,

[0053] The output sensitivity in the Fx direction is: .

[0054] When a load of Fy = 2500 N is applied, the third strain beam 3, the fourth strain beam 4, the seventh strain beam 7, and the eighth strain beam 8 undergo bending strain. Strain gauges R17 and R20 are subjected to tensile strain, and strain gauges R18 and R19 are subjected to compressive strain. The composition is as follows: Figure 4 Bridge 5 in the diagram, calculated using ANSYS Workbench, has the strain measured in R17 as follows: The dependent variable measured by R18 is The dependent variable measured by R19 is The dependent variable measured by R20 is ,but:

[0055] —This indicates the output voltage value in the Fy direction when Fx is fully loaded; — This represents the sensitivity coefficient of the strain gauge. In calculations, the average value is usually taken, with k=2. —This represents the strain measured in the R17 patch area of ​​the strain gauge; —This represents the strain measured in the R18 patch area of ​​the strain gauge; —This represents the strain measured in the R19 patch area of ​​the strain gauge; —This represents the strain measured in the R20 strain gauge patch area; —This represents the excitation voltage of the bridge circuit, which is taken here. .

[0056] ,

[0057] Then the output sensitivity in the Fy direction is: .

[0058] When a load of Fz = 5000 N is applied, the first strain beam 1, the second strain beam 2, the third strain beam 3, the fourth strain beam 3, the fifth strain beam 5, the sixth strain beam 6, the seventh strain beam 7, and the eighth strain beam 8 undergo bending deformation. Strain gauges R21, R23, R25, R27, R29, R31, R33, and R35 experience tensile strain, while strain gauges R22, R24, R26, R28, R30, R32, R34, and R36 experience compressive strain, forming bridge circuit 6 as shown in the figure. ANSYS Workbench calculations show that the strain measured at R21 is... The dependent variable measured by R22 is The dependent variable measured by R23 is The dependent variable measured by R24 is The dependent variable measured by R25 is The dependent variable measured by R26 is The dependent variable measured by R27 is The dependent variable measured by R28 is The dependent variable measured by R29 is The dependent variable measured by R30 is The dependent variable measured by R31 is The dependent variable measured by R32 is The dependent variable measured by R33 is The dependent variable measured by R34 is The dependent variable measured by R35 is The dependent variable measured by R36 is ,but:

[0059] —This indicates the output voltage value in the Fz direction when Fz is fully loaded; — This represents the sensitivity coefficient of the strain gauge. In calculations, the average value is usually taken, with k=2. —This represents the strain measured at the R21 patch area of ​​the strain gauge; —This represents the strain measured at the R22 patch area of ​​the strain gauge; —This represents the strain measured in the R23 patch area of ​​the strain gauge; —This represents the strain measured in the R24 patch area of ​​the strain gauge; —This represents the strain measured in the R25 patch area of ​​the strain gauge; —This represents the strain measured in the R26 patch area of ​​the strain gauge; —This represents the strain measured at the R27 patch area of ​​the strain gauge; —This represents the strain measured in the R28 patch area of ​​the strain gauge; —This represents the strain measured at the R29 patch area of ​​the strain gauge; —This represents the strain measured in the R30 patch area of ​​the strain gauge; —This represents the strain measured at the R31 patch area of ​​the strain gauge; —This represents the strain measured at the R32 patch area of ​​the strain gauge; —This represents the strain measured at the R33 patch area of ​​the strain gauge; —This represents the strain measured at the R34 patch area of ​​the strain gauge; —This represents the strain measured in the R35 patch area of ​​the strain gauge; —This represents the strain measured at the R36 patch area of ​​the strain gauge; —This represents the excitation voltage of the bridge circuit, which is taken here. .

[0060] ,

[0061] Then the output sensitivity in the Fz direction is: .

[0062] When a load of Mx = 1000 Nm is applied, the first strain beam 1, the second strain beam 2, the fifth strain beam 5, and the sixth strain beam 6 undergo bending deformation. Strain gauges R1, R4, R37, and R40 experience tensile strain, while strain gauges R2, R3, R38, and R39 experience compressive strain, forming bridge circuit 1 as shown in the figure. ANSYS Workbench calculations show that the strain measured by R1 is... The dependent variable measured by R² is The dependent variable measured by R3 is The dependent variable measured by R4 is The dependent variable measured by R37 is The dependent variable measured by R38 is The dependent variable measured by R39 is The dependent variable measured by R40 is but:

[0063] —This represents the output voltage value in the Mx direction when Mx is fully loaded; — This represents the sensitivity coefficient of the strain gauge. In calculations, the average value is usually taken, with k=2. —This represents the strain measured in the R13 patch area of ​​the strain gauge; —This represents the strain measured in the R14 patch area of ​​the strain gauge; —This represents the strain measured in the R15 patch area of ​​the strain gauge; —This represents the strain measured in the R16 patch area of ​​the strain gauge; —This represents the strain measured in the R13 patch area of ​​the strain gauge; —This represents the strain measured in the R14 patch area of ​​the strain gauge; —This represents the strain measured in the R15 patch area of ​​the strain gauge; —This represents the strain measured in the R16 patch area of ​​the strain gauge; —This represents the excitation voltage of the bridge circuit, which is taken here. .

[0064] ,

[0065] The output sensitivity in the Mx direction is: .

[0066] When My = 1000 Nm is applied, the third strain beam 3, the fourth strain beam 4, the seventh strain beam 7, and the eighth strain beam 8 undergo bending deformation. Strain gauges R5 and R8 are subjected to tensile strain, and strain gauges R6 and R7 are subjected to compressive strain, forming bridge circuit 2 as shown in the figure. ANSYS Workbench calculations show that the strain measured at R5 is... The dependent variable measured by R6 is The dependent variable measured by R7 is The dependent variable measured by R8 is The dependent variable measured by R41 is The dependent variable measured by R42 is The dependent variable measured by R43 is The dependent variable measured by R44 is but:

[0067] —This indicates the output voltage value in the My direction when My is fully loaded; — This represents the sensitivity coefficient of the strain gauge. In calculations, the average value is usually taken, with k=2. —This represents the strain measured in the R5 patch area of ​​the strain gauge; —This represents the strain measured in the R6 patch area of ​​the strain gauge; —This represents the strain measured in the R7 patch area of ​​the strain gauge; —This represents the strain measured in the R8 patch area of ​​the strain gauge; —This represents the strain measured at the R41 patch area of ​​the strain gauge; —This represents the strain measured at the R42 patch area of ​​the strain gauge; —This represents the strain measured at the R43 patch area of ​​the strain gauge; —This represents the strain measured at the R44 patch area of ​​the strain gauge; —This represents the excitation voltage of the bridge circuit, which is taken here. .

[0068] , The output sensitivity in the My direction is: .

[0069] When Mz = 500 Nm is applied, all strain beams (1, 2, 3, 4, 5, 6, 7, and 8) undergo bending deformation. Strain gauges R9 and R12 experience tensile strain, while strain gauges R10 and R11 experience compressive strain, forming bridge circuit 3 as shown in the figure. ANSYS Workbench calculations show that the strain measured by R9 is... The dependent variable measured by R10 is The dependent variable measured by R11 is The dependent variable measured by R12 is ,but:

[0070] —This represents the output voltage value in the Mz direction when Mz is fully loaded; — This represents the sensitivity coefficient of the strain gauge. In calculations, the average value is usually taken, with k=2. —This represents the strain measured in the R9 patch area of ​​the strain gauge; —This represents the strain measured in the R10 patch area of ​​the strain gauge; —This represents the strain measured in the R11 patch area of ​​the strain gauge; —This represents the strain measured in the R12 patch area of ​​the strain gauge; —This represents the excitation voltage of the bridge circuit, which is taken here. .

[0071] , The output sensitivity in the Mz direction is: .

[0072] In summary, based on the strength and sensitivity analysis results, the integrated six-dimensional portable force measuring plate of this embodiment can withstand high strength, has high sensitivity, and high accuracy.

[0073] The above embodiments are only for illustrating the technical concept of this utility model and should not be construed as limiting the scope of protection of this utility model. Any modifications made to the technical solution based on the technical concept proposed by this utility model shall fall within the scope of protection of this utility model.

Claims

1. A portable, integrated six-dimensional force measuring board, characterized in that, The force plate is placed on the ground and includes an elastomer (14) and a protective assembly disposed outside the elastomer (14). The elastic body (14) is square in shape and includes a hub (18), a force-bearing platform (19), and multiple strain beams. The force-bearing platform (19) is located in the middle of the hub (18), and multiple strain beams connect the hub (18) and the force-bearing platform (19). Multiple strain gauges are attached to different positions on the strain beams. The force-bearing platform (19) has a through hole (21) in the middle. Inside the through hole (21) is a bridge plate (12) for forming a Wheatstone bridge and a data acquisition board (13) for collecting the output signal of the conversion elastomer (14). Multiple wires are led out from the strain gauge and welded to the bridge plate (12) to form six Wheatstone bridges, which are used to detect forces and torques in three directions, denoted as Fx, Fy, Fz, Mx, My, and Mz. The protective assembly includes an upper cover plate (11), a lower cover plate (16), a top cover plate (10), and a back plate (15). The upper cover plate (11) and the lower cover plate (16) are respectively connected to the upper and lower surfaces of the hub (18) and both cover the strain beam. The top cover plate (10) and the back plate (15) are respectively set on the upper and lower surfaces of the force-bearing platform (19) and both cover the through hole (21) in the middle of the force-bearing platform (19).

2. The integrated six-dimensional portable force measuring plate according to claim 1, characterized in that: The cross-section of the elastomer (14) is square.

3. The integrated six-dimensional portable force measuring plate according to claim 1, characterized in that: The protective assembly also includes a top plate (9), which is disposed on the top cover plate (10) and covers the top cover plate (10), the upper cover plate (11) and the entire elastomer (14).

4. The integrated six-dimensional portable force measuring plate according to claim 1, characterized in that: Two wiring channels (20) are provided on the force-bearing platform (19) for each strain beam, and the wires connecting the strain gauge and the bridge plate (12) pass through the wiring channels (20).

5. The integrated six-dimensional portable force measuring plate according to claim 3, characterized in that: A connecting groove (23) is provided on the side wall of the hub (18) for each strain beam. One end of the strain beam is connected to the inside of the connecting groove (23), and the other end of the strain beam is connected to the force table (19).

6. The integrated six-dimensional portable force measuring plate according to claim 5, characterized in that: The strain beam is a T-shaped column, including a horizontal beam and a vertical beam. The cross-section of the horizontal beam and the vertical beam is square. The horizontal beam is set in the connecting groove (23). The side of the horizontal beam is connected to one end of the vertical beam, and the other end of the vertical beam is connected to the force-bearing platform (19).

7. The integrated six-dimensional portable force measuring plate according to claim 1, characterized in that: Eight strain beams are set between the hub (18) and the load-bearing platform (19), and a total of 44 strain gauges are set on the eight strain beams.

8. The integrated six-dimensional portable force measuring plate according to claim 3, characterized in that: A foot (17) is provided on the lower surface of the hub (18).

9. The integrated six-dimensional portable force measuring plate according to claim 1, characterized in that: The data acquisition board (13) is equipped with a first connector (24) for connecting the power supply line, a second connector (25) for connecting the series power line, and a third connector (26) for connecting the signal transmission line.

10. The integrated six-dimensional portable force measuring plate according to claim 1, characterized in that: Six Wheatstone bridges form a full-bridge circuit.

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