KR101759102B1

KR101759102B1 - Improving performance wheel dynamometer on rotation

Info

Publication number: KR101759102B1
Application number: KR1020150126214A
Authority: KR
Inventors: 주진원; 박용욱
Original assignee: 충북대학교 산학협력단
Priority date: 2015-09-07
Filing date: 2015-09-07
Publication date: 2017-07-18
Also published as: KR20170029197A

Abstract

The present invention is based on the assumption that three pairs of beams measure Fx, Fy, Fz, Mx, My, and Mz, respectively, and a directional performance during rotation, which can obtain an output value for each force transmitted at three positions at a time, And a load disk which is provided inside the outer ring body and includes a central shaft and is capable of being subjected to a load, and an outer ring body connected to the outer ring body and the rod disk, And a plurality of strain gauges attached respectively to the four faces of the six load beams, wherein the strain gauges are attached to a pair of symmetrical load beams of the six load beams, The strain gauges provide a six-axis wheel dynamometer that improves directional performance during rotation to measure Fx, Fy, Fz, Mx, My, and Mz.

Description

[0001] The present invention relates to a six-axis wheel dynamometer,

The present invention is based on the assumption that three pairs of beams measure Fx, Fy, Fz, Mx, My, and Mz, respectively, and a directional performance during rotation, which can obtain an output value for each force transmitted at three positions at a time, To a six-axis wheel dynamometer

Generally, a load cell is used as a sensor for measuring force. Due to the development of robots due to the automation of industry, the importance of measuring the force and torque generated in the arbitrary direction and the position control in the three-dimensional space is increasing, and especially the force In a control type robot, a multi-component force sensor is one of the key components playing an important role.

A multi-component load cell consists of a load cell with an orthogonal elastic structure consisting of eight parallel leaf springs, a parallel plate measuring force components, and a radial plate measuring moments. A component load cell is disclosed in Patent Publication No. 0199691. However, such a load cell can reduce the characteristics such as mutual interference errors by disposing the sensing units for sensing loads, while the structure is too complex to be used for control of robots and the like, so that the production cost is increased and the mutual interference error is reduced The complexity of the bridge circuit is increased, and the weight of the bridge circuit is large.

The structure which can overcome such disadvantages is a structure in which the sensing part has a plurality of beam shapes. ATI company in the US has commercialized a 6-axis load cell using the top and bottom surfaces of three beam detectors located at 120-degree intervals. However, the load cell of the three beam structure is complicated by the detection of all loads, and the output value of the sensing unit is low. Therefore, a silicon gauge whose gauge constant is several tens times larger than that of a general gauge is used, which can increase the output value of each load, but the error due to noise and nonlinearity also occurs. In addition, there is a disadvantage in that a silicon gauge, which is several tens to several hundred times more expensive than a general gauge, is used and a post-treatment process is required to deal with the error caused by mutual interference, thereby forming a high price.

A multi-component load cell that improves this is a six-axis force-moment sensing line disclosed in Japanese Patent Application Laid-Open No. 10-2011-0098070, in which four beams are arranged in a cross shape, and a plate structure is provided on the outer ring, . However, in such a structure, not only can the signal of the sensing part not be enlarged due to a large stress, but also the flexibility of various loads is reduced by attaching a plurality of strain gages to a small beam, , There is a problem that it is difficult to use as a commodity.

SUMMARY OF THE INVENTION The present invention has been made to solve the various problems including the above problems, and it is an object of the present invention to provide a method and a device for measuring output, It is possible to provide a six-axis wheel dynamometer which improves the directional performance during rotation, which is a great help in case of failure. However, these problems are exemplary and do not limit the scope of the present invention.

According to one aspect of the present invention, there is provided an air bag comprising: a ring-shaped outer ring body; a rod disk including a central axis and provided inside the outer ring body and capable of applying a load; And a plurality of strain gauges attached respectively to the four faces of the six load beams, wherein strain gauges attached to a pair of symmetrical load beams of the six load beams The gauge is provided with a six-axis wheel dynamometer that improves directional performance during rotation to measure Fx, Fy, Fz, Mx, My, and Mz.

The plurality of strain gauges may be slantedly attached to the extension direction of the load beam.

The plurality of strain gauges attached to either side of the six load beams may have a cross shape with four.

The plurality of strain gauges may be inclined at an angle of 45 DEG with respect to the extending direction of the load beam.

At least one of the six load beams may include a concave seating groove formed on a side surface of the load disk in a direction intersecting the center axis of the load disk and to which the strain gauge is attached.

And a spring block which is provided between the outer ring body and the load beam and has both ends connected to the outer ring body and a center portion connected to the load beam.

According to an embodiment of the present invention as described above, the output data can be fed back by comparing the respective forces, and more precise measurement can be performed in an average sense. If the output acquisition per second can not be set infinitely high, It is possible to implement a six-axis wheel dynamometer which improves the directional performance during the rotation. Of course, the scope of the present invention is not limited by these effects.

1 is a plan view schematically illustrating a six-axis wheel dynamometer according to an embodiment of the present invention.
2 is a perspective view schematically illustrating a six-axis wheel dynamometer according to an embodiment of the present invention.
3 is an enlarged view schematically showing a six-axis wheel dynamometer according to an embodiment of the present invention.
4 is an enlarged view schematically showing a six-axis wheel dynamometer according to an embodiment of the present invention.
5 and 6 are perspective views schematically showing a part of a six-axis wheel dynamometer according to an embodiment of the present invention.
7 and 8 are perspective views schematically showing a part of a six-axis wheel dynamometer according to an embodiment of the present invention.
9 is a circuit diagram schematically showing a Wheatstone bridge circuit of a six-axis wheel dynamometer according to an embodiment of the present invention.
10 is a partial perspective view schematically showing a six-axis wheel dynamometer according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be understood, however, that the invention is not limited to the disclosed embodiments, but may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, Is provided to fully inform the user. Also, for convenience of explanation, the components may be exaggerated or reduced in size.

In the following embodiments, the x-axis, the y-axis, and the z-axis are not limited to three axes on the orthogonal coordinate system, and can be interpreted in a broad sense including the three axes. For example, the x-axis, y-axis, and z-axis may be orthogonal to each other, but may refer to different directions that are not orthogonal to each other.

While the invention is susceptible to various modifications and alternative forms, specific embodiments thereof are shown by way of example in the drawings and will herein be described in detail. It should be understood, however, that the invention is not intended to be limited to the particular embodiments, but includes all modifications, equivalents, and alternatives falling within the spirit and scope of the invention. Like reference numerals are used for like elements in describing each drawing.

The terms first, second, A, B, etc. may be used to describe various elements, but the elements should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as a second component, and similarly, the second component may also be referred to as a first component. And / or < / RTI > includes any combination of a plurality of related listed items or any of a plurality of related listed items.

It is to be understood that when an element is referred to as being "connected" or "connected" to another element, it may be directly connected or connected to the other element, . On the other hand, when an element is referred to as being "directly connected" or "directly connected" to another element, it should be understood that there are no other elements in between.

The terminology used in this application is used only to describe a specific embodiment and is not intended to limit the invention. The singular expressions include plural expressions unless the context clearly dictates otherwise. In the present application, the terms "comprises" or "having" and the like are used to specify that there is a feature, a number, a step, an operation, an element, a component or a combination thereof described in the specification, But do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in commonly used dictionaries are to be interpreted as having a meaning consistent with the contextual meaning of the related art and are to be interpreted as either ideal or overly formal in the sense of the present application Do not.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

Hereinafter, the + z direction will be referred to as upward, the -z direction will be referred to as downward, and the x direction and y direction will be referred to as left and right.

FIG. 1 is a plan view schematically showing a six-axis wheel dynamometer for improving directional performance during rotation according to an embodiment of the present invention. FIG. 2 is a plan view of a six- 1 is a perspective view schematically showing a wheel dynamometer.

The six-axis wheel dynamometer which improves the directional performance during rotation according to the present embodiment includes an outer ring body 100, a rod disk 200, six load beams 1, 3, 5, 7, 9, 11, Gauge < / RTI >

The outer ring body 100 is formed in a ring shape and can serve as a fixed end of the entire wheel dynamometer.

The rod disk 200 has a central axis and may be formed in a substantially disc shape. The central axis is parallel to the z-direction and can cross the center of gravity of the rod disk 200.

Then, the load disc 200 is able to transmit a load to the load beams 1, 3, 5, 7, 9, 11 by a load acting thereon. Specifically, the rod disk 200 may include a hole 210 for applying a load. Here, the holes 210 are formed in the z direction and can penetrate through the rod disk 200.

The six load beams 1, 3, 5, 7, 9, 11 can connect the outer ring body 100 and the load disk 200. Specifically, the six load beams 1, 3, 5, 7, 9, and 11 may be disposed at approximately 60 degrees with respect to the center axis. Three pairs of load beams 1, 3, 5, 7, 9, 11 can be provided. Hereinafter, the six load beams 1, 3, 5, 7, 9, and 11 may be referred to as a first load beam 1 to a sixth load beam 11.

The load beams 1, 3, 5, 7, 9, and 11 may connect the outer ring body 100 and the rod disk 200 and include two pairs of opposite sides. For example, the load beams 1, 3, 5, 7, 9, 11 may include opposing upper and lower surfaces, opposite sides. More specifically, the load beams 1, 3, 5, 7, 9, 11 may be in a square beam shape.

3 and 4, a plurality of strain gauges 300 can be attached to each of the four faces of each of the six load beams 1, 3, 5, 7, 9, 11. That is, a plurality of strain gauges 300 can be attached to the top, bottom, and both sides of the load beams 1, 3, 5, 7, 9, Here, strain gage 300 may be of a shear type.

In addition, the six-axis wheel dynamometer according to the present embodiment is provided between the outer ring body 100 and the load beams 1, 3, 5, 7, 9, 11 and has both ends connected to the outer ring body 100, The spring blocks 21, 23, 25, 27, 29 and 31 connected to the load beams 1, 3, 5, 7, 9 and 11, respectively. The spring blocks 21, 23, 25, 27, 29 and 31 can more accurately measure the force. The load beam (1, 3, 5, 7, 9, 11) and the spring block serve to sense the force, and the spring block can be elastically deformed and elastically deformed.

The slits 41, 43, 45, 47, 49 and 51 formed by the spring blocks 21, 23, 25, 27, 29 and 31 and the outer ring body 100 have widths Can be expanded. This is to ensure that the force is transmitted to the load beams 1, 3, 5, 7, 9, 11 in a precise manner.

A pair of load beams 1, 3, 5, 7, 9, 11 symmetrical among the six load beams 1, 3, 5, 7, 9, 11 Fy, Fz, Mx, My, and Mz when a load acts on the strain gages 300 attached to the four load beams 7. As shown in more detail, the strain gauges 300, Can be attached to one side of one load beam 1, 3, 5, 7, 9, 11. And the four strain gauges 300 can be cross-shaped so that a total of 96 strain gages 300 ) May be attached.

The strain gauge 300 may be attached at an angle (?) Inclined with respect to the extending direction of the load beams 1, 3, 5, 7, 9, 11. More specifically, the strain gage 300 can be inclined at 45 degrees with respect to the direction in which the load beams 1, 3, 5, 7, 9, 11 extend. The extension direction of the load beams 1, 3, 5, 7, 9, 11 may be a direction connecting the outer ring body 100 and the rod disk 200 in a direction perpendicular to the central axis.

5 and 6 are perspective views schematically showing a first load beam 1 and a fourth load beam 7 forming a pair. The six load beams 1, 3, 5, 7, 9, 11 are arranged in pairs with load beams 1, 3, 5, 7, 9, 11 symmetrically opposed to each other, Paired. The pair of load beams 1 and 7 measure the forces Fx, Fy, Fz, Mx, My and Mz generated in the wheel dynamometer. The remaining two pairs of load beams 3, 5, Also measure the forces Fx, Fy, Fz, Mx, My, and Mz in the same manner. Therefore, the six-axis force is measured three times in total.

FIGS. 7 and 8 are perspective views showing in more detail the forces measured in FIGS. 5 and 6, and FIG. 9 is a table showing the forces measured by each strain gauge 300 based on the Wheatstone bridge.

The strain gauges 300 attached to the three pairs of load beams 1, 3, 5, 7, 9 and 11 are identical in position and circuit configuration, so that the first rod 1 beam 1 and the fourth load beam 7, As a representative. At this time, Mx, My, and Fz are measured by the strain gauge 300 attached to the side surfaces of the load beams 1, 3, 5, 7, 9,

More specifically, the strain gage 300 attached to a pair of load beams 1, 3, 5, 7, 9, 11 can measure the force acting by the Wheatstone bridge circuit, .

According to the present embodiment, a pair of load beams 1, 3, 5, 7, 9 and 11 measure the forces Fx, Fy, Fz, Mx, My and Mz, Fx, Fx, Mx, My, and Mz are measured by the total three pairs of beams.

If this output is obtained, the wheel dynamometer, which continuously obtains the output value, can obtain three output values at different positions at intervals of 60 ° when the force of Fx is applied at any moment.

It is also possible to feed back the output data by comparing each force, and to enable more precise measurement in the mean sense.

It also has the same effect of acquiring three data at a time, so it can be a great help if you can not set the output per second to be infinitely high. Specifically, since the wheel dynamometer measures the load received from the road surface that can not be predicted during high-speed rotation, according to the present embodiment, as in the case of a conventional cross-shaped beam, The load beam 1, 3, 5, 7, 9, 11 can measure the force of one axis and can use this data more accurately.

10 is a perspective view schematically showing a part of a six-axis wheel dynamometer which improves directional performance during rotation according to another embodiment of the present invention. The six-axis wheel dynamometer according to the present embodiment further includes an additional configuration in the above-described embodiment. Therefore, redundant description will be omitted.

According to the present embodiment, at least one of the six load beams 1, 3, 5, 7, 9, and 11 is formed on a side surface located in a direction intersecting the central axis of the rod disk 200, 300 may be attached.

Specifically, the load beams 1, 3, 5, 7, 9, and 11 may include concave seating grooves 400 formed on the top and bottom surfaces of the load beams 1, And the strain gauge 300 can be attached to the flat surface in the seating groove 400.

While the present invention has been described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. Accordingly, the true scope of the present invention should be determined by the technical idea of the appended claims.

1, 3, 5, 7, 9, 11: load beam 100: outer ring body
200: load disk 300: strain gauge
400: seat groove

Claims

A ring-shaped outer ring body (100);
A load disk 200 including a central axis, which is provided inside the outer ring body 100 and to which a load can be applied;
Six load beams (1, 3, 5, 7, 9, 11) connecting the outer ring body (100) and the rod disk (200) and including two facing pairs of faces; And
And a plurality of strain gauges (300) attached respectively to the four faces of the six load beams (1,3,5,7,9,11)
The strain gauges 300 attached to a pair of symmetrical load beams of the six load beams 1,3,5,7,9,11 measure Fx, Fy, Fz, Mx, My and Mz,
The outer ring member 100 and the load beam, both ends connected to the outer ring member, and the center member connected to the load beams 1, 3, 5, 7, 9 and 11, Further comprising a spring block (21, 23, 25, 27, 29, 31)
Wherein a material is removed on the upper and lower surfaces of the load beams (1,3,5,7,9,11) to improve the output value, thereby forming a concave seating groove (400) 6-axis wheel dynamometer with improved performance.

The method according to claim 1,
Wherein the plurality of strain gauges (300) are attached obliquely to the direction of extension of the load beams (1,3,5,7,9,11).

3. The method of claim 2,
The plurality of strain gauges 300 attached to either side of the six load beams 1, 3, 5, 7, 9, 11 are arranged in a four-sided cross- Dynamometer.

3. The method of claim 2,
Wherein the plurality of strain gauges (300) are inclined at an angle of 45 degrees with respect to the direction of extension of the load beams (1,3,5,7,9,11).

delete

The method according to claim 1,
The slits 41, 43, 45, 47, 49, 51 formed by the spring blocks 21, 23, 25, 27, 29, 31 and the outer ring body 100 have a wider width Wherein the six-axis wheel dynamometer improves directional performance during rotation.