WO2012129882A1

WO2012129882A1 - Three-dimensional space vibration measuring device and method

Info

Publication number: WO2012129882A1
Application number: PCT/CN2011/078602
Authority: WO
Inventors: 黄永辉; 黄毅; 吴斌兴
Original assignee: 长沙中联重工科技发展股份有限公司; 湖南中联重科专用车有限责任公司
Priority date: 2011-03-29
Filing date: 2011-08-18
Publication date: 2012-10-04
Also published as: CN102226713A; CN102226713B

Abstract

A three-dimensional vibration measuring device comprising: a support bracket, three cable-type displacement sensors, and a processor; the support bracket is provided with three mounting parts, and the mounting parts are fixedly located on the three axes (x, y and z) normal to each other in a three-dimensional coordinate system respectively; each of the three cable-type displacement sensors comprises a main body (4,5,6) and a cable pulled out from the main body (4', 5' and 6'), the main bodies are mounted on the mounting parts respectively, and the ends of the cables can intersect at the measuring point (7) in a space limited by the main bodies and the origin of the three-dimensional coordinate system; the processor communicates with the three cable-type displacement sensors via a data acquisition device and processes the obtained data. Processing the measured signals with the vibration measuring device is simple and more accurate vibration displacement values can be obtained. Moreover, the vibration measuring device is simple in structure, easy in mounting and low in cost. The vibration measurement method is simple to operate and is easy to implement.

Description

TECHNICAL FIELD The present invention relates to a three-dimensional space vibration measuring device and method. BACKGROUND OF THE INVENTION In the field of heavy machinery, some complete machines (such as pump trucks) have a long boom structure. During operation, the end of the long boom structure is more or less vibrating, which may affect the positioning of the working surface and may also cause a safety accident. After the whole machine is designed and developed, it is necessary to test this aspect before leaving the factory to ensure the normal use of the user. However, in the vibration test, the single-degree-of-freedom vibration measuring device is relatively common, and the three-dimensional space vibration testing lacks the corresponding device and method. In the prior art, the following two methods are generally used to test the vibration: (1) The existing remote vibration test generally firstly measures the acceleration signal of the measured object, and then performs secondary integration and removal of the trend item processing, thereby The vibration displacement signal is obtained; (2) Three laser position sensitive device detectors (PSDs) are used to form an integrated laser measurement system, which can be used for accurate measurement of the positional deviation of the spatial flexible member. The above two methods of measuring vibration have respective disadvantages. The disadvantage of the first method is: Since the acceleration signal is measured first, there is a certain error in itself, and the error is further amplified after the second integration, and the frequency component and the interference frequency component of the object to be measured are not known. It is difficult to perform frequency truncation during filtering, so the resulting vibration displacement signal has a large distortion. The disadvantage of the second method is: When determining the deviation of the position of the flexible member, after measuring the angle of rotation of the flexible member, it is also necessary to know the deviation of the deflection, and then indirectly obtain the accurate displacement of the flexible member. . Moreover, in addition to destroying the end of the flexible rod to fix the PSD integrated device, it is necessary to fix a laser emitting device at the front end of the flexible rod, and the system is complicated and costly. SUMMARY OF THE INVENTION An object of the present invention is to provide a three-dimensional spatial vibration measuring device and method for solving the problems of the prior art vibration measuring device having a complicated structure, high cost, and low measurement accuracy. In order to solve the above technical problem, according to an aspect of the present invention, a three-dimensional spatial vibration measuring device is provided. In particular, the three-dimensional spatial vibration measuring device comprises: a bracket having three mounting portions, and the mounting portions are respectively positioned in three-dimensional space coordinates Three pull-line displacement sensors; each of the wire-type displacement sensors, each of the wire-type displacement sensors includes a body and a pull wire pulled from the body, the body is respectively mounted on the mounting portion, and the ends of the wire can intersect at a measuring point in a space defined by the origin and the origin of the three-dimensional coordinate system; and a processor that communicates with the three pull-line displacement sensors through the acquisition device and processes the obtained data. Further, the bracket includes three arms extending respectively along three axes, each of the arms including a first end and an opposite second end, the first ends are rigidly coupled together, and the three mounting portions are respectively disposed at three On the arm. Further, the lengths of the three arms are equal. Further, the mounting portion is mounted on the second end, and the body is mounted on the mounting portion. Further, the mounting portion includes a mounting plate fixedly coupled to the second end. Further, the mounting portion includes a bracket and a mounting plate rotatably coupled to the bracket. Further, the three arms are each of an elongated structure, and an oblique support reinforcement is disposed between at least two of the three arms. According to another aspect of the present invention, there is also provided a three-dimensional spatial vibration measuring method, in particular, comprising the steps of: a) setting a three-dimensional space coordinate system, respectively positioning three bodies of three wire-type displacement sensors respectively The three-dimensional coordinate system is perpendicular to the three axes; b) positioning the three-dimensional space coordinate system such that the measuring points of the object to be measured are located in a space defined by the origins of the three bodies and the three-dimensional space coordinate system; c) three The ends of the three pull wires of the pull-type displacement sensor are fixed on the measuring points, the initial lengths of the three pull wires are recorded to calculate two possible initial coordinates of the measuring points, and the actual initial coordinate values are determined; d) the object to be tested is generated Vibrate, thereby driving the vibration of the measuring point for testing, recording the vibration length of the three pull wires at any time to calculate the two possible vibration coordinates of the measuring point, and determining the actual vibration coordinate value; and e) utilizing in step d) The obtained vibration coordinate value is subtracted from the difference of the initial coordinate values obtained in the step c), and the vibration displacement at an arbitrary timing is calculated. Further, the bodies of the three wire-type displacement sensors are equidistant from the origin of the three-dimensional space coordinate system. Further, the position of the measuring point is located on the side far from the origin of the plane defined by the drawn ends of the three pull wires, and the three bodies are rotatable on three axes. Further, data is collected by the acquisition device and processed by the processor. The invention has the following technical effects: Firstly, with the three-dimensional spatial vibration measuring device and method according to the present invention, the processing of the measurement signal is simple and direct, and a more accurate vibration displacement value can be obtained; Secondly, the three-dimensional spatial vibration measuring device according to the present invention has a simple structure, is convenient to install, and has low cost, and the three-dimensional spatial vibration detecting method of the present invention is simple in operation and easy to implement. The above general description and the following detailed description are intended to be illustrative of the invention BRIEF DESCRIPTION OF THE DRAWINGS The accompanying drawings, which are incorporated in FIG The drawings illustrate the preferred embodiments of the invention, and, together with 2 shows a schematic perspective view of a three-dimensional spatial vibration measuring device in accordance with a preferred embodiment of the present invention. Fig. 3 shows a schematic perspective view of a sensor mounting portion of a three-dimensional spatial vibration measuring device in accordance with a preferred embodiment of the present invention. Fig. 4 shows a schematic exploded perspective view of the sensor mounting portion of Fig. 3. Fig. 5 shows a schematic perspective view of a three-dimensional spatial vibration measuring device according to a second embodiment of the present invention. Fig. 6 is a schematic perspective view showing a sensor mounting portion of a three-dimensional spatial vibration measuring device according to a second embodiment of the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, specific embodiments of the present invention will be described in detail with reference to the accompanying drawings. It should be noted that only the features of the present invention which are different from the prior art will be described below, and the technical features that can be found in the prior art will not be described here. For ease of understanding, the basic principles of the present invention are briefly explained first. The three-dimensional spatial vibration measuring device of the invention uses three wire-type displacement sensors to measure the vibration displacement signals of the measured object in the corresponding three directions, and then converts the signals of the three wire-type displacement sensors into three by the space coordinate conversion method. Vibration displacements on mutually perpendicular degrees of freedom. Referring first to Figure 2, a preferred embodiment of the three-dimensional spatial vibration measuring device of the present invention is described. The vibration measuring device comprises: a bracket composed of three equal angle arms 1, 2, 3, three The first ends of the arms 1, 2, 3 are rigidly connected together by bolts and define the origin 0 of the three-dimensional space coordinate system, three arms 1, 2, 3 extending perpendicularly from the origin O; three pull-line displacement sensors, each sensor comprising bodies 4, 5, 6 and pull wires 4', 5', 6' pulled from the bodies, these bodies 4, 5 And 6 are respectively mounted on the second ends of the three arms 1, 2, 3 opposite to the first end, and the ends of the wires can intersect the measuring points 7 in the space defined by the three arms 1, 2, 3 And a processor (not shown) such as a computer that communicates with the three pull-line displacement sensors through a collection device (not shown) and processes the obtained data. In order to enhance the stability of the vibration measuring device of the present invention, further, oblique support members 8, 9, 10 made of steel plates are further disposed between the three arms 1, 2, 3. Of course, the invention is not limited to the provision of a diagonal support reinforcement between all three arms, but may also be achieved by partial reinforcement, for example, only a support reinforcement is provided between the two arms. It should be noted that in the present embodiment, although the three arms 1, 2, 3 are made of three angles, and the diagonal support members 8, 9, 10 are steel plates, those skilled in the art should It is to be understood that the invention is not limited thereto, and any suitable other materials are also included in the scope of the invention. Furthermore, the mounting portions on the three arms 1, 2, 3 of the embodiment shown in Figure 2 preferably comprise interconnecting mounting plates 11 and a fixed connection (e.g., by welding) to the underlying mounting plate 11 The bracket 14 of the arm, the mounting plate 11 has a coupling hole 13 that cooperates with a connector (not shown) on the body of the wire-type displacement sensor. Preferably, the mounting plate 11 and the bracket 14 are coupled by a rotating shaft 12 such that the mounting plate 11 is free to rotate about the rotational axis 12 within a range of 180 degrees, see in particular Figures 3 and 4. It will be understood by those skilled in the art that the lower surface of the mounting plate 11 is ensured to be freely rotated by a rotating shaft 12, so that the cable wires 4', 5', 6' of the wire-type displacement sensor can be expanded and contracted along the exit direction. In order to reduce the friction of the cable, the accuracy of the test can also be guaranteed. Further, according to the second embodiment in which the structure of the present invention is more simplified, referring to FIGS. 5 and 6, the mounting portion is a fixed connection (for example, by welding) to the mounting plate of the arm (specifically, a bending plate 15), and the wire is pulled. The body of the sensor is mounted on the bent plate 15. It can be understood that although this type of installation cannot achieve follow-up, the object of the present invention can be achieved. For a better understanding of the present invention, further description will be made below with reference to Figures 1 - 3 in conjunction with the specific operation of the apparatus. First, the three-dimensional spatial vibration measuring device is fixed on the ground or a platform that can approach the measured point. It can be understood that, due to the self-weight of the arms 1, 2, 3 themselves, it can be easily fixed on the ground or the platform, if necessary, can also be fixed by a weight, or is known in the art. Any way fixed. Then, the three bodies 4, 5, 6 of the appropriate range of the wire displacement sensor are fixed on the respective mounting plates (it is conceivable that these wire-type displacement sensors are always installed at the corresponding positions), and the cable is pulled out. It is fixed on the measuring point 7 of the measured object by fasteners to ensure that the motion of the measured object is limited to the range of ^{χ +} ^ ^{+ ζ > α} . Referring specifically to Fig. 1, a detailed description will be given of how the vibration-related displacement value is calculated by the value obtained from the wire sensor. 1, "FIG cube side length (corresponding to three support 2, the length of the arm 13),, J ₃ are mounted on the three axes x, y, wire cable length sensor on Z, corresponding to The coordinates satisfy the following relationship:

L ₂ -x -z = (ay)

(2)

L -x -y =(a- z)

(3) The joint solution can be solved:

and so:

L, ―

-+ x

2a (6)

A _ 2 + x

2a (7) Generation back (1)

^ - (^ ^ + x) ² - + ) ² = (a - X)

2a 2a (8)

This will give you two sets of solutions (ΐ, Υΐ, Ζ!), (Χ ₂ , , 3⁄4). The above two solutions are actually possible. There is a solution on each side of the plane Χ + + Ζ ". But in fact, the vibration solution of the boom is unique, so the solution needs to be traded off. The position is defined on the side of the plane x + _y ₊ z = a away from the origin, ie the point _{7 is} limited to the space expressed by x + ^ + a. It is understood that due to the amplitude of the vibration relative to the three arms The space defined is very small, so it is easy to limit the position of the measuring point. By measuring the measured data of the linear displacement sensor, the vibration displacement signal of three degrees of freedom can be obtained. The coordinates that need to be solved at the start time are set to (x ₀ , y ₀ , z ₀ ). Thus, the vibration displacement at any time can be obtained by the difference between the coordinates after the vibration and the initial coordinates: X0 (10) d _Yt =y _t -y ₀

(11) - ^z o (12) It should be understood that in the preferred embodiment of the invention described above, the three arms are of equal length. The same is true for the general case where the lengths of the three arms are not equal. This case is described in detail below. ", b, c are the lengths of the three arms. To facilitate the coordinate selection, the motion of the measured object is limited to x/a + _y/6 + z/ _C > Within the scope of l. J ₂ and J ₃ are the cable lengths of the wire sensors mounted on the three axes, respectively, and the corresponding coordinates satisfy the following relationship:

Ll X

(14) _ ^x -y =( ^c _ ^z ) (15) Lianli can be solved:

L _x -L ₂ =a —b — lax + 2by

(17) So: J: -Li -a +ca

―—— +—

2c c (18)

L -Ll-a ² +b ² a

y =— +—

2b b (19) Substituting the equation (1) gives: r _? , l -il-a ² +c ² a , ₇ , ΐ -L -a ² +b ² a , _Ί , , ₇

L: -(-- +- ) - (―—— +— ) =(a- x)

¹ 2c c 2b b (20)

a

(1 + ΤΓ +- ) +[— ( ^Z I -a ) +— (L -L ₂ -a )]x

Becb

This will give you two sets of solutions (ΐ, Υΐ, Ζ!), (Χ ₂ , , 3⁄4). The above two solutions are actually possible, and there is a solution on each side of the plane x/«+_y/6 + z/ c = l. However, the vibration solution of the boom is unique here, so the solution needs to be traded off. For the trade-off, the position of the measuring point is limited to the side of the plane x/" + _y/6 + z/c = l away from the origin, and S卩 limits the measuring point to W" + _y/6 + z/c> l In the space expressed. It will also be appreciated that since the amplitude of the vibration is small relative to the space defined by the three arms, it is easy to define the position of the measurement points. The coordinates of the measured pull-line displacement sensor are coordinate-converted to obtain a vibration displacement signal in three degrees of freedom. After starting the acquisition, the coordinates to be solved at the start time need to be set to (x ₀ , y ₀ , z ₀ ). Thus, the vibration displacement at any time can be obtained by the difference between the coordinates after the vibration and the initial coordinates: d _xt (22) d _yt = y _{t -} y ₀ (23) (24) It can be seen from the above two different embodiments that the three-dimensional vibration measuring device and method according to the present invention can relatively accurately measure the vibration displacement of the long boom structure, and can also be used to check the three-dimensional spatial vibration displacement test based on the wireless acceleration sensor. Further, although the present invention relates to three-dimensional spaces that are perpendicular to each other, those skilled in the art will appreciate that the present invention can also be implemented by converting coordinates in other forms of three-dimensional space into coordinates in a vertical three-dimensional space. The above is only the preferred embodiment of the present invention, and is not intended to limit the present invention, and various modifications and changes can be made to the present invention. Any modifications, equivalents, improvements, etc. made within the spirit and scope of the present invention are intended to be included within the scope of the present invention.

Claims

Claim

A three-dimensional spatial vibration measuring device, wherein the three-dimensional spatial vibration measuring device comprises:

The bracket has three mounting portions, and the mounting portions are respectively positioned on three mutually perpendicular axes of the three-dimensional space coordinate system;

a three-wire displacement sensor, each of the wire-type displacement sensors comprising a body and a pull wire drawn from the body, the body being respectively mounted on the mounting portion, the ends of the wire being capable of intersecting a point in the space defined by the origin and the origin of the three-dimensional coordinate system;

The processor communicates with the three pull-line displacement sensors through the acquisition device and processes the obtained data.

2. The three-dimensional spatial vibration measuring device according to claim 1, wherein the bracket comprises three arms respectively extending along the three axes, each of the arms including a first end and an opposite The second end, the first ends are rigidly coupled together, and the three mounting portions are respectively disposed on the three arms.

3. The three-dimensional spatial vibration measuring device according to claim 2, wherein the three arms are equal in length.

The three-dimensional spatial vibration measuring device according to claim 2 or 3, wherein the mounting portion is mounted on the second end, and the body is mounted on the mounting portion.

The three-dimensional spatial vibration measuring device according to claim 4, wherein the mounting portion includes a mounting plate fixedly coupled to the second end.

The three-dimensional spatial vibration measuring device according to claim 4, wherein the mounting portion includes a bracket and a mounting plate rotatably coupled to the bracket.

7. The three-dimensional spatial vibration measuring device according to claim 2 or 3, wherein the three arms are each an elongated structure and between at least two of the three arms An oblique support reinforcement is provided.

8. A three-dimensional spatial vibration measuring method, comprising the steps of:

a) setting a three-dimensional space coordinate system, respectively, three bodies of the three wire-type displacement sensors are respectively positioned on three mutually perpendicular axes of the three-dimensional space coordinate system;

b) positioning the three-dimensional space coordinate system such that the measuring points of the object to be measured are located in a space defined by the origins of the three bodies and the three-dimensional space coordinate system; C) fixing the ends of the three pull wires of the three wire-type displacement sensors on the measuring points, recording the initial lengths of the three pull wires to calculate two possible initial coordinates of the measuring points, and determining Actual initial coordinate value;

d) causing the object to be tested to vibrate, thereby driving the measuring point to perform vibration test, recording the vibration length of the three pull wires at any time to calculate two possible vibration coordinates of the measuring point, and determining Actual vibration coordinate values;

e) calculating the vibration displacement at an arbitrary timing by subtracting the difference of the initial coordinate values obtained in the step c) by the vibration coordinate value obtained in the step d).

9. The three-dimensional spatial vibration measuring method according to claim 8, wherein the bodies of the three linear displacement sensors are equal to a distance from an origin of the three-dimensional space coordinate system.

The three-dimensional spatial vibration measuring method according to claim 8, wherein the position of the measuring point is located on a side of the plane defined by the drawing end of the three pulling wires away from the origin, and The three bodies are rotatable on the three axes.

11. The three-dimensional spatial vibration measuring method according to claim 8, wherein the data is collected by the collecting device and processed by the processor.