阅读说明：本技术 一种模态试验支撑装置及使用方法 (Modal test supporting device and using method ) 是由 康传明 安佰华 梁晗星 林谢伟 郭懿霆 于 2021-08-10 设计创作，主要内容包括：本发明公开了一种模态试验支撑装置及使用方法,该装置包括：用于悬吊被试件的悬吊结构；设于悬吊结构下方的支撑结构,用于支撑被试件；悬吊结构和支撑结构相匹配,使模态试验支撑装置的刚度为零；支撑结构包括反刚度菱框、可伸缩套筒、水平弹性部件和底座,可伸缩套筒分别与反刚度菱框和底座连接,水平弹性部件连接反刚度菱框的对角线；其中,悬吊结构包括悬吊横梁、第一弹性部件和第二弹性部件,第一弹性部件和第二弹性部件平行连接于悬吊横梁,用于悬吊被试件,且第一弹性部件和第二弹性部件的弹性刚度系数均为水平弹性部件的弹性刚度系数的一半。本发明的模态试验支撑装置刚度低,满足低频结构的模态试验要求,进而提高了试验可信度性。(The invention discloses a modal test supporting device and a using method thereof, wherein the device comprises: a suspension structure for suspending the tested piece; the supporting structure is arranged below the suspension structure and used for supporting a tested piece; the suspension structure is matched with the support structure, so that the rigidity of the modal test support device is zero; the supporting structure comprises a reverse-stiffness diamond frame, a telescopic sleeve, a horizontal elastic part and a base, wherein the telescopic sleeve is respectively connected with the reverse-stiffness diamond frame and the base, and the horizontal elastic part is connected with a diagonal line of the reverse-stiffness diamond frame; the suspension structure comprises a suspension cross beam, a first elastic component and a second elastic component, wherein the first elastic component and the second elastic component are connected to the suspension cross beam in parallel and used for suspending a tested piece, and the elastic stiffness coefficients of the first elastic component and the second elastic component are half of the elastic stiffness coefficient of the horizontal elastic component. The modal test supporting device is low in rigidity, meets the modal test requirement of a low-frequency structure, and further improves the test reliability.)

1. A modal testing support assembly, comprising:

the suspension structure is used for suspending a tested piece;

the supporting structure is arranged below the suspension structure and used for supporting the tested piece, and the suspension structure is matched with the supporting structure so that the rigidity of the modal test supporting device is zero;

the supporting structure comprises a reverse-stiffness diamond frame, a telescopic sleeve, a horizontal elastic part and a base, wherein the base is arranged below the reverse-stiffness diamond frame, the telescopic sleeve is respectively connected with the reverse-stiffness diamond frame and the base, and the horizontal elastic part is connected with a diagonal line of the reverse-stiffness diamond frame;

the suspension structure comprises a suspension cross beam, a first elastic component and a second elastic component, wherein the first elastic component and the second elastic component are connected to the suspension cross beam in parallel and used for suspending the tested piece, the elastic stiffness coefficients of the first elastic component and the second elastic component are the same, and the elastic stiffness coefficients of the first elastic component and the second elastic component are half of the elastic stiffness coefficient of the horizontal elastic component.

2. A modal test support assembly as recited in claim 1, wherein the inverse stiffness diamond frame includes a first diamond frame strut, a second diamond frame strut, a third diamond frame strut, a fourth diamond frame strut, and a first hinge, a second hinge, a third hinge, and a fourth hinge connected in series, the first diamond frame strut and the second diamond frame strut, the second diamond frame strut and the third diamond frame strut, the third diamond frame strut and the fourth diamond frame strut, the fourth diamond frame strut and the first diamond frame strut are hinged sequentially by the first hinge, the second hinge, the third hinge, and the fourth hinge.

3. A modal test support assembly according to claim 2, wherein the second hinge is located at a bottom of the counter-stiffness diamond and the fourth hinge is located at a top of the counter-stiffness diamond.

4. A modal test support assembly as set forth in claim 3 wherein the horizontal resilient member is disposed between the first and third hinges.

5. A modal test support assembly as recited in claim 3, wherein the telescoping sleeve comprises a barrel and a slide bar disposed within the barrel, one end of the slide bar being connected to a bottom of the fourth hinge, the other end of the slide bar being disposed within the barrel, the second hinge being fixedly attached to a sidewall of the lower portion of the barrel, the slide bar sliding within the barrel to deform the inverted stiffness diamond frame.

6. A modal test support assembly as set forth in claim 5 wherein the other end of the slide bar is connected within the barrel by a linear bearing.

7. A modal test support assembly as set forth in claim 3, wherein a rubber head is provided at a top of the fourth hinge, and the rubber head is connected with the tested piece.

8. A modal test support assembly as set forth in claim 5, wherein the base includes a support post and a horizontal support plate, the support post being disposed below the horizontal support plate, the horizontal support plate being connected to the support post and the barrel, respectively, and the barrel passing through the horizontal support plate.

9. A modal test support assembly as set forth in claim 5, wherein the first, second, third, fourth and slide bars are made of an alloy material.

10. A method of using a modal test support assembly as defined in any of claims 1 to 9, comprising:

placing a tested piece on a supporting structure and suspending the tested piece through a suspension structure;

after the suspended tested piece is balanced and static, adjusting the first diamond frame supporting rod, the second diamond frame supporting rod, the third diamond frame supporting rod and the fourth diamond frame supporting rod to enable the first diamond frame supporting rod to be overlapped with the second diamond frame supporting rod, the third diamond frame supporting rod to be overlapped with the fourth diamond frame supporting rod, and the first diamond frame supporting rod and the third diamond frame supporting rod to be located on the same horizontal line.

Technical Field

The invention belongs to the field of machinery, and particularly relates to a modal test supporting device and a using method thereof.

Background

The experimental modal analysis is also called modal analysis experimental process, which is called modal experiment for short, is the inverse process of theoretical modal analysis, is one of the methods for verifying the reliability of finite element analysis, and is also one of the necessary and effective means for carrying out structure dynamic design. In the modal experiment, whether the supporting mode of the tested structural part is proper or not is very important, because the structure has different modal parameters under different boundary conditions. The modal experiment is a test that a large-scale solar unmanned aerial vehicle, an airplane or a structural member with large flexibility must complete, but because the tested piece has large size and large flexibility, the inherent frequency of the tested piece is generally very low, the conventional supporting tool is difficult to meet the test requirement, and the test reliability is greatly reduced. Therefore, a modal test support device with high test reliability is particularly needed.

Disclosure of Invention

The invention aims to provide a modal test supporting device with high test reliability and a using method thereof.

In order to achieve the above object, the present invention provides a modal test supporting apparatus, including: the suspension structure is used for suspending a tested piece; the supporting structure is arranged below the suspension structure and used for supporting the tested piece, and the suspension structure is matched with the supporting structure so that the rigidity of the modal test supporting device is zero; the supporting structure comprises a reverse-stiffness diamond frame, a telescopic sleeve, a horizontal elastic part and a base, wherein the base is arranged below the reverse-stiffness diamond frame, the telescopic sleeve is respectively connected with the reverse-stiffness diamond frame and the base, and the horizontal elastic part is connected with a diagonal line of the reverse-stiffness diamond frame; the suspension structure comprises a suspension cross beam, a first elastic component and a second elastic component, wherein the first elastic component and the second elastic component are connected to the suspension cross beam in parallel and used for suspending the tested piece, the elastic stiffness coefficients of the first elastic component and the second elastic component are the same, and the elastic stiffness coefficients of the first elastic component and the second elastic component are half of the elastic stiffness coefficient of the horizontal elastic component.

Preferably, the reverse-rigidity diamond frame comprises a first diamond frame supporting rod, a second diamond frame supporting rod, a third diamond frame supporting rod, a fourth diamond frame supporting rod, a first hinge, a second hinge, a third hinge and a fourth hinge which are sequentially connected, the first diamond frame supporting rod, the second diamond frame supporting rod and the third diamond frame supporting rod are sequentially hinged, and the third diamond frame supporting rod, the fourth diamond frame supporting rod and the first diamond frame supporting rod are sequentially hinged through the first hinge, the second hinge, the third hinge and the fourth hinge.

Preferably, the second hinge is located at the bottom of the inverse stiffness diamond frame, and the fourth hinge is located at the top of the inverse stiffness diamond frame.

Preferably, the horizontal elastic component is arranged between the first hinge and the third hinge.

Preferably, the telescopic sleeve comprises a barrel body and a sliding rod arranged in the barrel body, one end of the sliding rod is connected with the bottom of the fourth hinge, the other end of the sliding rod is arranged in the barrel body, the second hinge is fixedly connected to the side wall of the lower portion of the barrel body, and the sliding rod slides in the barrel body, so that the inverse-rigidity diamond frame deforms.

Preferably, the other end of the slide bar is connected to the inside of the cylinder through a linear bearing.

Preferably, a rubber head is arranged at the top of the fourth hinge and connected with the tested piece.

Preferably, the base comprises a supporting column and a horizontal supporting plate, the supporting column is arranged below the horizontal supporting plate, the horizontal supporting plate is respectively connected with the supporting column and the cylinder, and the cylinder penetrates through the horizontal supporting plate.

Preferably, the first diamond frame supporting rod, the second diamond frame supporting rod, the third diamond frame supporting rod, the fourth diamond frame supporting rod and the sliding rod are all made of alloy materials.

The invention also provides a use method of the modal test supporting device, which comprises the following steps: placing a tested piece on a supporting structure and suspending the tested piece through a suspension structure; after the suspended tested piece is balanced and static, adjusting the first diamond frame supporting rod, the second diamond frame supporting rod, the third diamond frame supporting rod and the fourth diamond frame supporting rod to enable the first diamond frame supporting rod to be overlapped with the second diamond frame supporting rod, the third diamond frame supporting rod to be overlapped with the fourth diamond frame supporting rod, and the first diamond frame supporting rod and the third diamond frame supporting rod to be located on the same horizontal line.

The invention has the beneficial effects that: the modal test supporting device is low in rigidity, meets the modal test requirement of a low-frequency structure, further improves the test reliability, and is simple and reliable in composition, good in robustness and easy to operate.

The present invention has other features and advantages which will be apparent from or are set forth in detail in the accompanying drawings and the following detailed description, which are incorporated herein, and which together serve to explain certain principles of the invention.

Drawings

The above and other objects, features and advantages of the present invention will become more apparent by describing in more detail exemplary embodiments thereof with reference to the attached drawings. Wherein like reference numerals generally refer to like parts throughout the exemplary embodiments of the invention.

Fig. 1 shows a structural block diagram of a modal test support apparatus according to an embodiment of the present invention.

Fig. 2 shows a schematic structural diagram of a counter-stiffness diamond frame of a modal test support apparatus according to an embodiment of the invention.

Description of reference numerals:

1. a suspension structure; 2. a tested piece; 3. a suspension cross beam; 4. a reverse stiffness diamond frame; 5. a barrel; 6. a base; 41. a first diamond frame strut; 42. a second diamond frame strut; 43. a third diamond frame strut; 44. a fourth diamond frame strut; 45. a first hinge; 46. a second hinge; 47. a third hinge; 48. a fourth hinge; 49. a horizontal elastic member; 50. a rubber head; 51. a slide bar; 52. a linear bearing; 61. a horizontal support plate; 62. and (4) a support column.

Detailed Description

Preferred embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. While the preferred embodiments of the present invention are shown in the drawings, it should be understood that the present invention may be embodied in various forms and should not be limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

The modal test supporting device comprises: the suspension structure is used for suspending the tested piece; the supporting structure is arranged below the suspension structure and used for supporting the tested piece, and the suspension structure is matched with the supporting structure so that the rigidity of the modal test supporting device is zero; the supporting structure comprises a reverse-rigidity diamond frame, a telescopic sleeve, a horizontal elastic part and a base, wherein the base is arranged below the reverse-rigidity diamond frame, the telescopic sleeve is respectively connected with the reverse-rigidity diamond frame and the base, and the horizontal elastic part is connected with a diagonal line of the reverse-rigidity diamond frame; the suspension structure comprises a suspension cross beam, a first elastic component and a second elastic component, wherein the first elastic component and the second elastic component are connected to the suspension cross beam in parallel and used for suspending a tested piece, the elastic stiffness coefficients of the first elastic component and the second elastic component are the same, and the elastic stiffness coefficients of the first elastic component and the second elastic component are half of the elastic stiffness coefficient of the horizontal elastic component.

Specifically, solar unmanned aerial vehicle hangs on hanging in midair the crossbeam by suspension structure, suspension structure can choose for use the rubber rope, elastic element such as spring, solar unmanned aerial vehicle below is supported by bearing structure, bearing structure includes anti-rigidity diamond frame, telescopic sleeve, base and horizontal elastic component, anti-rigidity diamond frame sets up on telescopic sleeve, telescopic sleeve fixed connection is on the base, the base sets up in the below of anti-rigidity diamond frame, the base is placed subaerially at the level, horizontal elastic component sets up on the diagonal of anti-rigidity diamond frame.

The suspension structure comprises a first elastic component and a second elastic component which have the same elastic stiffness coefficient, and in order to enable the stiffness of the modal test supporting device to be zero, the first elastic component and the second elastic component which have the elastic stiffness coefficient half of that of the horizontal elastic component are selected.

The rigidity of the modal test supporting device is the ratio of stress to deformation of the modal test supporting device when the modal test supporting device is used for carrying out a modal test, and the smaller the rigidity of the modal test supporting device is, the more accurate the result of the modal test is.

Setting the elastic stiffness coefficient of the first elastic memberK _v Is the elastic stiffness coefficient of the horizontal elastic partK _h Half of that. The mechanical relationship of the supporting system is as follows:

assuming that the elastic stiffness coefficient of the horizontal elastic member isK _h The elastic stiffness coefficient of the vertical first elastic member isK _v The mass of the vibration isolation is m, and the rest mass is temporarily ignored. The x axis is upward, and the point where the 4 diamond-shaped support rods are horizontally overlapped is the x zero point.

Under the action of the gravity of the mass block, the vertical first elastic component deforms: deltax=mg/K _v

Under the action of external force, the stress of the whole corner shearing mechanism is expressed as follows:，

wherein: x represents the position of the upward movement of the mass,

wherein:

the comprehensive formula can be expressed as: (1)

order:

expression (1) translates into:

the zero stiffness conditions were:

wherein, x is the original length of the first elastic component, and L is the length of the diamond frame strut.

From the above analysis, when the elastic stiffness coefficient of the horizontal elastic component is 2 times of the elastic stiffness coefficient of the first elastic component in the vertical direction, the whole supporting device has the characteristic of approximately zero stiffness. Therefore, when the elastic stiffness coefficient of the first elastic member and the second elastic member is half of the elastic stiffness coefficient of the horizontal elastic member, the stiffness of the entire support device is zero or approximately zero.

According to the exemplary embodiment, the modal test supporting device is low in rigidity, meets the modal test requirements of a low-frequency structure, further improves test reliability, and is simple and reliable in composition, good in robustness and easy to operate.

According to the preferable scheme, the reverse-rigidity diamond frame comprises a first diamond frame supporting rod, a second diamond frame supporting rod, a third diamond frame supporting rod, a fourth diamond frame supporting rod, a first hinge, a second hinge, a third hinge and a fourth hinge which are sequentially connected, the first diamond frame supporting rod, the second diamond frame supporting rod and the third diamond frame supporting rod are hinged, and the third diamond frame supporting rod, the fourth diamond frame supporting rod and the first diamond frame supporting rod are sequentially hinged through the first hinge, the second hinge, the third hinge and the fourth hinge.

Specifically, the reverse-rigidity diamond frame is formed by sequentially hinging 4 diamond frame supporting rods together through 4 hinges.

Preferably, the second hinge is located at the bottom of the inverse stiffness diamond frame, and the fourth hinge is located at the top of the inverse stiffness diamond frame.

Specifically, the hinge located at the bottom of the inverse-rigidity diamond frame is a second hinge, the hinge located at the top of the inverse-rigidity diamond frame is a fourth hinge, the hinge located at the right part of the inverse-rigidity diamond frame is a first hinge, and the hinge located at the left part of the inverse-rigidity diamond frame is a third hinge.

Preferably, a horizontal elastic part is arranged between the first hinge and the third hinge.

Specifically, the left first hinge and the right first hinge are connected through a horizontal elastic component, a rubber head is mounted on the upper fourth hinge, and the lower portion of the fourth hinge is fixedly connected with the sliding rod.

As the preferred scheme, the telescopic sleeve comprises a barrel body and a sliding rod arranged in the barrel body, one end of the sliding rod is connected with the bottom of the fourth hinge, the other end of the sliding rod is arranged in the barrel body, the side wall of the lower portion of the barrel body is fixedly connected with the second hinge, and the sliding rod slides in the barrel body, so that the inverse-rigidity diamond frame deforms.

Specifically, the second hinge is fixed on the side wall of the cylinder, the sliding rod is connected into the cylinder through a linear bearing, the cylinder is vertically installed on the horizontal supporting plate, and when the diamond frame supporting rod of the diamond frame with the reverse rigidity is adjusted, the sliding rod slides in the cylinder, so that the diamond frame with the reverse rigidity deforms.

Preferably, the other end of the slide rod is connected to the cylinder body through a linear bearing.

Preferably, a rubber head is arranged at the top of the fourth hinge and connected with the tested piece.

Specifically, the tested piece is placed on the rubber head at the top of the fourth hinge.

As preferred scheme, the base includes support column and horizontal support plate, and the support column setting is in the below of horizontal support plate, and horizontal support plate is connected with support column and barrel respectively, and the barrel passes horizontal support plate.

Specifically, the support column is arranged below the horizontal support plate, a cylinder is arranged on the horizontal support plate and connected with the inverse-rigidity diamond frame, and the slide rod slides in the cylinder to drive the inverse-rigidity diamond frame to deform.

Preferably, the first diamond frame supporting rod, the second diamond frame supporting rod, the third diamond frame supporting rod, the fourth diamond frame supporting rod and the sliding rod are made of alloy materials.

Specifically, 4 frame rhombus branch and slide bar all adopt aluminum alloy material to make, and the rubber head adopts the great rubber material of elasticity.

The invention also provides a use method of the modal test supporting device, which comprises the following steps: placing a tested piece on a supporting structure and suspending the tested piece through a suspension structure; after the suspended tested piece is balanced and static, adjusting the first diamond frame supporting rod, the second diamond frame supporting rod, the third diamond frame supporting rod and the fourth diamond frame supporting rod to enable the first diamond frame supporting rod to be overlapped with the second diamond frame supporting rod, the third diamond frame supporting rod to be overlapped with the fourth diamond frame supporting rod, and the first diamond frame supporting rod and the third diamond frame supporting rod to be located on the same horizontal line.

Before use, the solar unmanned aerial vehicle is balanced and static under the suspension effect of two elastic parts of a suspension structure, 4 diamond frame supporting rods are adjusted to be horizontal and positioned on the same horizontal line, the horizontal elastic structure is in a maximum stretching state, and a rubber head is pressed against the structure at the gravity center position of the solar unmanned aerial vehicle; in this configuration, the stiffness of the modal testing apparatus is zero or approximately zero and the modal test is started.

Examples

Fig. 1 shows a structural block diagram of a modal test support apparatus according to an embodiment of the present invention. Fig. 2 shows a schematic structural diagram of a counter-stiffness diamond frame of a modal test support apparatus according to an embodiment of the invention.

Referring to fig. 1 and 2, the modal test support apparatus includes: the suspension structure 1, the suspension structure 1 is used for suspending the tested piece 2; the supporting structure is arranged below the suspension structure 1 and used for supporting the tested piece 2, and the suspension structure 1 is matched with the supporting structure so that the rigidity of the modal test supporting device is zero; the supporting structure comprises a reverse-stiffness diamond frame 4, a telescopic sleeve, a horizontal elastic part 49 and a base 6, wherein the base 6 is arranged below the reverse-stiffness diamond frame 4, the telescopic sleeve is respectively connected with the reverse-stiffness diamond frame 4 and the base 6, and the horizontal elastic part 49 is connected with a diagonal line of the reverse-stiffness diamond frame 4; the suspension structure 1 comprises a suspension cross beam 3, a first elastic component and a second elastic component, wherein the first elastic component and the second elastic component are connected to the suspension cross beam 3 in parallel and used for suspending the tested piece 2, the elastic stiffness coefficients of the first elastic component and the second elastic component are the same, and the elastic stiffness coefficients of the first elastic component and the second elastic component are half of the elastic stiffness coefficient of the horizontal elastic component 49.

The reverse-rigidity diamond frame 4 comprises a first diamond frame supporting rod 41, a second diamond frame supporting rod 42, a third diamond frame supporting rod 43, a fourth diamond frame supporting rod 44, a first hinge 45, a second hinge 46, a third hinge 47 and a fourth hinge 48 which are sequentially connected, the first diamond frame supporting rod 41, the second diamond frame supporting rod 42 and the third diamond frame supporting rod 43 are sequentially hinged, and the third diamond frame supporting rod 43, the fourth diamond frame supporting rod 44 and the first diamond frame supporting rod 41 are sequentially hinged through the first hinge 45, the second hinge 46, the third hinge 47 and the fourth hinge 48.

Wherein the second hinge 46 is located at the bottom of the counter-rigid rhomb 4 and the fourth hinge 48 is located at the top of the counter-rigid rhomb 4.

Wherein a horizontal elastic member 49 is provided between the first hinge 45 and the third hinge 47.

The telescopic sleeve comprises a barrel body 5 and a sliding rod 51 arranged in the barrel body, one end of the sliding rod 51 is connected with the bottom of a fourth hinge 48, the other end of the sliding rod 51 is arranged in the barrel body 5, a second hinge 46 is fixedly connected to the side wall of the lower portion of the barrel body 5, and the sliding rod 51 slides in the barrel body 5, so that the reverse-rigidity diamond frame 4 deforms.

Wherein the other end of the slide rod 51 is connected to the inside of the cylinder 5 through a linear bearing 52.

Wherein, the top of the fourth hinge 48 is provided with a rubber head 50, and the rubber head 50 is connected with the tested piece 2.

Wherein, base 6 includes support column 62 and horizontal support plate 61, and support column 62 sets up the below at horizontal support plate 61, and horizontal support plate 61 is connected with support column 62 and barrel 5 respectively, and barrel 5 passes horizontal support plate 61.

The first diamond frame supporting rod 41, the second diamond frame supporting rod 42, the third diamond frame supporting rod 43, the fourth diamond frame supporting rod 44 and the sliding rod 51 are all made of alloy materials.

Having described embodiments of the present invention, the foregoing description is intended to be exemplary, not exhaustive, and not limited to the disclosed embodiments. Many modifications and variations will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the illustrated embodiments.