A uniaxial force / torque sensor and measurement method

Abstract

The present invention discloses a uniaxial force / torque sensor and measurement method. The sensor comprises a floating platform, a fixed platform, a moment-measuring column beam, a force-measuring strain beam, and a foundation column beam. The upper surface of the fixed platform is fixedly connected to the lower end face of a vertically arranged moment-measuring column beam, and the upper end face of the moment-measuring column beam is fixedly connected to the ends of four horizontally arranged force-measuring strain beams. The other end of each force-measuring strain beam is fixedly connected to the lower end face of a vertically arranged foundation column beam, and the upper end faces of the four foundation column beams are fixedly connected to the lower surface of the floating platform. The present invention independently and accurately measures uniaxial force and torque, has a simple and compact structure, and is efficient and reliable.

Description

Technical Field

[0001] The present invention relates to a mechanical force sensor, in particular to a uniaxial force / torque sensor. Background Art

[0002] When conducting force measurement experiments on traditional motor shafts, the motor axial force and torque are usually measured independently using a one-dimensional force sensor and a torque sensor respectively, and the force and torque data are monitored simultaneously, but the mutual interference between force and torque cannot be eliminated. Traditional two-dimensional force balances can only achieve two-dimensional force measurement, two-dimensional torque measurement, or non-axial two-dimensional force and torque measurement. If a six-dimensional force balance is used for single-axial force / torque measurement, due to the complex structure and large size of the six-dimensional force balance, the measurement will be complicated, there will be more interference, and the measurement will be inaccurate. Therefore, it is necessary to develop a single-axial force / torque sensor that can measure single-axial force and torque (i.e., X / Mx or Y / My or Z / Mz). Summary of the Invention

[0003] Purpose of the invention: In view of the above shortcomings, the present invention provides a uniaxial force / torque sensor that can directly realize independent measurement of uniaxial forces and uniaxial torques in various directions.

[0004] The present invention also provides a method for measuring the above-mentioned uniaxial force / torque sensor.

[0005] To achieve the above objectives, the uniaxial force / torque sensor provided by the present invention adopts the following technical solutions:

[0006] A uniaxial force / torque sensor comprises a fixed platform, a moment-measuring column beam extending from one surface of the fixed platform, a floating platform fixed to the front end of the moment-measuring column beam, a force-measuring strain beam extending outwardly from the moment-measuring column beam, and a foundation column beam extending from the first surface of the floating platform facing the fixed platform; the force-measuring strain beam has four mutually perpendicular columns uniformly distributed around the moment-measuring column beam, the foundation column beam also has four columns uniformly distributed on the first surface of the floating platform, the force-measuring strain beams are connected to the foundation column beams in a one-to-one correspondence, one end of each force-measuring strain beam is fixed to the moment-measuring column beam and the other end is fixed to the foundation column beam; the side surface of the moment-measuring column beam is perpendicular to the first surface of the floating platform, the force-measuring strain beam has a second surface facing the floating platform and a third surface facing the fixed platform; the second surface and the third surface are both parallel to the first surface; the side surface of the moment-measuring column beam and the second surface and the third surface of the force-measuring strain beam are all used to attach strain gauges.

[0007] Furthermore, strain gauges are attached to the side surfaces of the moment-measuring column beam to measure uniaxial moment; strain gauges are attached to the second surface and the third surface of the force-measuring strain beam to measure uniaxial force.

[0008] Furthermore, when the moment measuring column beam independently measures the uniaxial moment, the force measuring strain beam is not patched; when the force measuring strain beam independently measures the uniaxial force, the moment measuring column beam is not patched but only serves as a supporting base for the force measuring strain beam.

[0009] Furthermore, the four force-measuring strain beams are symmetrically arranged and evenly distributed along the circumference to offset the influence of torque, realize force and moment decomposition, and together with the foundation column beam form the basis of the moment-measuring column beam to realize the moment-measuring column beam to efficiently measure uniaxial torque while ensuring the torsional stiffness of the structure.

[0010] Furthermore, the torque measuring column beam has an independent matching range, and patch processing is performed on the surface of the torque measuring column beam, so that the torque signal can be output separately; the four force measuring strain beams have independent matching ranges, and patch processing is performed on the surface of the force measuring strain beam, so that the force signal can be output separately; the uniaxial force and torque range settings do not interfere with each other, and the measurements do not disturb each other.

[0011] The measurement method using the above-mentioned uniaxial force / torque sensor provided by the present invention can adopt the following technical solutions:

[0012] A measurement method according to the above-mentioned single axial force / torque sensor, determining the direction of the axial force and axial moment to be measured, and aligning the axial direction of the moment measuring column beam with the direction;

[0013] When independently measuring the axial moment in this direction, two opposite sides of the moment measuring column beam are selected to attach strain gauges, and the torsional strain on the column beam surface is output as a voltage signal using a Wheatstone bridge to independently measure the uniaxial moment.

[0014] When independently measuring the axial force in this direction, two force-measuring strain beams extending in opposite directions are selected from the four force-measuring strain beams, and strain gauges are attached to the second and third surfaces of the two force-measuring strain beams respectively. The bending strain of the surfaces of the two force-measuring strain beams is output through voltage signals using a Wheatstone bridge, so that the uniaxial force can be independently measured.

[0015] Beneficial effects: Compared with the prior art, the present invention can decompose uniaxial force and torque, and realize independent measurement of uniaxial force and torque. The four force-measuring strain beams are symmetrically arranged and evenly distributed along the circumference, which can effectively offset the influence of torque and realize force and torque decomposition. Together with the foundation column beam, they form the basis of the vertically arranged moment-measuring column beam, so that the vertically arranged moment-measuring column beam can efficiently measure uniaxial torque while ensuring the torsional stiffness of the structure. The moment-measuring column beam not only measures uniaxial torque independently, but also serves as the basis of the four force-measuring strain beams, so that the force-measuring strain beam can efficiently measure uniaxial force and ensure the axial stiffness of the structure. The uniaxial force and torque range settings do not interfere with each other, and the measurements do not disturb each other, which can achieve high-precision measurement, and the structure is simple and compact, efficient and reliable. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 1 is a schematic structural diagram of a uniaxial force / torque sensor according to the present invention;

[0017] Figure 2 is a front view of the uniaxial force / torque sensor of the present invention;

[0018] Figure 3 is a main cross-sectional view of the uniaxial force / torque sensor of the present invention;

[0019] Figure 4 is a top sectional view of a uniaxial force / torque sensor of the present invention;

[0020] Figure 5 This is a patch diagram for measuring the X-axis uniaxial moment in the present invention;

[0021] Figure 6 Schematic diagram of a Wheatstone bridge for independently measuring the X-axis uniaxial torque in the present invention;

[0022] Figure 7 This is a patch diagram for measuring the X-axis uniaxial force in the present invention;

[0023] Figure 8 Schematic diagram of a Wheatstone bridge for independently measuring X-axis uniaxial force in the present invention;

[0024] Figure 9 This is the state diagram of the sensor measuring the Y-axis uniaxial force / torque;

[0025] Figure 10 This is a patch diagram for measuring the Y-axis uniaxial torque in the present invention;

[0026] Figure 11 Schematic diagram of a Wheatstone bridge for independently measuring the Y-axis uniaxial torque in the present invention;

[0027] Figure 12 This is a patch diagram for measuring the Y-axis uniaxial force in the present invention;

[0028] Figure 13 Schematic diagram of the Wheatstone bridge for independently measuring the Y-axis uniaxial force in the present invention;

[0029] Figure 14 This is the state diagram of the sensor measuring the Z-axis uniaxial force / torque;

[0030] Figure 15 This is a patch diagram for measuring the Z-axis uniaxial moment in the present invention;

[0031] Figure 16 Schematic diagram of a Wheatstone bridge for independently measuring the Z-axis uniaxial torque in the present invention;

[0032] Figure 17This is a patch diagram for measuring Z-axis uniaxial force in the present invention;

[0033] Figure 18 Schematic diagram of the Wheatstone bridge for independently measuring the Z-axis uniaxial force in the present invention. DETAILED DESCRIPTION

[0034] See also Figures 1 to 4 As shown, the present invention discloses the preferred embodiments of the present invention below in conjunction with the accompanying drawings. It should be understood that the preferred embodiments described herein are only used to illustrate and explain the present invention, and are not used to limit the present invention.

[0035] like Figures 1 to 4 As shown, a uniaxial force / torque sensor of the present invention includes a fixed platform 1, a moment measuring column beam 2 extending from one surface of the fixed platform 1, a floating platform 5 fixed to the front end of the moment measuring column beam 2, a force measuring strain beam 3 extending circumferentially outward from the moment measuring column beam 2, and a basic column beam 4 extending from the first surface of the floating platform 5 facing the fixed platform 1.

[0036] The force-measuring strain beams 3 have four mutually perpendicular beams evenly distributed around the moment-measuring column beam 2, that is, evenly distributed at 90 degrees around the circumference, which can effectively offset the influence of torque and realize force and moment decomposition. The foundation column beams 4 also have four evenly distributed beams on the first surface of the floating platform 5. The force-measuring strain beams 3 are connected to the foundation column beams 4 in a one-to-one correspondence. One end of each force-measuring strain beam 3 is fixed to the moment-measuring column beam 2 and the other end is fixed to the foundation column beam 4. The side surface of the moment-measuring column beam 2 is perpendicular to the first surface of the floating platform 5. The force-measuring strain beam 3 has a second surface facing the floating platform 5 and a third surface facing the fixed platform 1. The second surface and the third surface are both parallel to the first surface. The side surface of the moment-measuring column beam, the second surface and the third surface of the force-measuring strain beam are all used to attach strain gauges.

[0037] The specific measurement method using a uniaxial force / torque sensor of the present invention is as follows:

[0038] When it is necessary to measure the X-axial force X and X-axial moment Mx, such as Figures 5 to 8 As shown, first align the axial direction of the moment measuring column beam with the X-axis.

[0039] When measuring the axial torque in the X-axis direction independently, such as Figure 5 As shown, in the side of the moment beam, two opposite sides are selected to be attached with strain gauges, one of which is attached with two strain gauges 21 and 22, and the other opposite side is symmetrical with the two strain gauges 21 and 22 and attached with another two strain gauges 23 and 24. Figure 6 The Wheatstone bridge shown outputs the torsional strain on the column beam surface through a voltage signal and independently measures the uniaxial moment Mx.

[0040] When measuring the axial force in the X-axis direction independently, such as Figure 7 As shown, among the four force-measuring strain beams, two force-measuring strain beams extending in opposite directions are selected, and strain gauges are attached to the second and third surfaces of the two force-measuring strain beams, respectively (two strain gauges 11 and 17 are attached to the second surface of one force-measuring strain beam, and two other strain gauges 13 and 15 are attached to the third surface symmetrically with the strain gauges 11 and 17; two strain gauges 12 and 18 are attached to the second surface of the other force-measuring strain beam, and two other strain gauges 14 and 16 are attached to the third surface symmetrically with the strain gauges 12 and 18). Figure 8 The Wheatstone bridge shown outputs the surface bending strain of the two force-measuring strain beams through voltage signals, and can independently measure the uniaxial force X.

[0041] When it is necessary to measure the Y-axis force Y and Y-axis moment My, such as Figure 9 As shown, first align the axial direction of the moment measuring column beam with the Y-axis.

[0042] When measuring the Y-axis axial moment independently, such as Figure 10 As shown, in the side of the moment beam, two opposite sides are selected to be attached with strain gauges, one of which is attached with two strain gauges 21 and 22, and the other opposite side is symmetrical with the two strain gauges 21 and 22 and attached with another two strain gauges 23 and 24. Figure 11 The Wheatstone bridge shown outputs the torsional strain on the column beam surface through a voltage signal and independently measures the uniaxial moment My.

[0043] When measuring the Y-axis force independently, such as Figure 12 As shown, among the four force-measuring strain beams, two force-measuring strain beams extending in opposite directions are selected, and strain gauges are attached to the second and third surfaces of the two force-measuring strain beams, respectively (two strain gauges 11 and 17 are attached to the second surface of one force-measuring strain beam, and two other strain gauges 13 and 15 are attached to the third surface symmetrically with the strain gauges 11 and 17; two strain gauges 12 and 18 are attached to the second surface of the other force-measuring strain beam, and two other strain gauges 14 and 16 are attached to the third surface symmetrically with the strain gauges 12 and 18). Figure 13 The Wheatstone bridge shown outputs the surface bending strain of the two force-measuring strain beams through voltage signals, and can independently measure the uniaxial force Y.

[0044] When it is necessary to measure the Z-axis force Z and the Z-axis moment Mz, such as Figure 14 As shown, first align the axial direction of the moment measuring column beam with the Z-axis.

[0045] When measuring the axial moment in the Z-axis independently, such as Figure 15 As shown, in the side of the moment beam, two opposite sides are selected to be attached with strain gauges, one of which is attached with two strain gauges 21 and 22, and the other opposite side is symmetrical with the two strain gauges 21 and 22 and attached with another two strain gauges 23 and 24. Figure 16 The Wheatstone bridge shown outputs the torsional strain on the column beam surface through a voltage signal and independently measures the uniaxial moment Mz.

[0046] When measuring the Y-axis force independently, such as Figure 17 As shown, among the four force-measuring strain beams, two force-measuring strain beams extending in opposite directions are selected, and strain gauges are attached to the second and third surfaces of the two force-measuring strain beams, respectively (two strain gauges 11 and 17 are attached to the second surface of one force-measuring strain beam, and two other strain gauges 13 and 15 are attached to the third surface symmetrically with the strain gauges 11 and 17; two strain gauges 12 and 18 are attached to the second surface of the other force-measuring strain beam, and two other strain gauges 14 and 16 are attached to the third surface symmetrically with the strain gauges 12 and 18). Figure 18 The Wheatstone bridge shown outputs the surface bending strain of the two force-measuring strain beams through voltage signals, and can independently measure the uniaxial force Z.

[0047] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or substitute equivalents for some of the technical features. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A uniaxial force / torque sensor, characterized in that: It includes a fixed platform, a moment measuring column beam extending from one surface of the fixed platform, a floating platform fixed to the front end of the moment measuring column beam, a force measuring strain beam extending outwardly in the circumferential direction of the moment measuring column beam, and a foundation column beam extending from the first surface of the floating platform facing the fixed platform; The force-measuring strain beams have four mutually perpendicular and evenly distributed around the moment-measuring column beam, and the foundation column beams also have four evenly distributed on the first surface of the floating platform. The force-measuring strain beams are connected to the foundation column beams in a one-to-one correspondence, and one end of each force-measuring strain beam is fixed to the moment-measuring column beam and the other end is fixed to the foundation column beam; The side surface of the moment measuring column beam is perpendicular to the first surface of the floating platform, and the force measuring strain beam has a second surface facing the floating platform and a third surface facing the fixed platform; the second surface and the third surface are both parallel to the first surface; the side surface of the moment measuring column beam and the second surface and the third surface of the force measuring strain beam are all used to attach strain gauges.

2. The uniaxial force / torque sensor according to claim 1, characterized in that: Strain gauges are attached to the side of the moment-measuring column beam to measure the uniaxial moment; strain gauges are attached to the second and third surfaces of the force-measuring strain beam to measure the uniaxial force.

3. The uniaxial force / torque sensor according to claim 2, characterized in that: When the moment measuring column beam independently measures the uniaxial moment, the force measuring strain beam is not patched; when the force measuring strain beam independently measures the uniaxial force, the moment measuring column beam is not patched but only serves as a supporting base for the force measuring strain beam.

4. The uniaxial force / torque sensor according to claim 1, 2 or 3, characterized in that: The four force-measuring strain beams are symmetrically arranged and evenly distributed along the circumference to offset the influence of torque, realize force and moment decomposition, and together with the foundation column beam form the basis of the moment-measuring column beam to realize the moment-measuring column beam to efficiently measure uniaxial torque while ensuring the torsional stiffness of the structure.

5. The uniaxial force / torque sensor according to claim 4, characterized in that: The torque measuring column beam has an independent matching range, and a patch process is performed on the surface of the torque measuring column beam, so that the torque signal can be output separately; the four force measuring strain beams have an independent matching range, and a patch process is performed on the surface of the force measuring strain beam, so that the force signal can be output separately; The uniaxial force and torque range settings do not interfere with each other, and the measurements do not disturb each other.

6. The method for measuring a uniaxial force / torque sensor according to any one of claims 1 to 5, characterized in that: Determine the direction of the axial force and axial moment to be measured, and align the axial direction of the moment measuring column beam with this direction; When independently measuring the axial moment in this direction, two opposite sides of the moment measuring column beam are selected to attach strain gauges, and the torsional strain on the column beam surface is output as a voltage signal using a Wheatstone bridge to independently measure the uniaxial moment. When independently measuring the axial force in this direction, two force-measuring strain beams extending in opposite directions are selected from the four force-measuring strain beams, and strain gauges are attached to the second and third surfaces of the two force-measuring strain beams respectively. The bending strain of the surfaces of the two force-measuring strain beams is output through voltage signals using a Wheatstone bridge, so that the uniaxial force can be independently measured.

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