A flexible support six-degree-of-freedom micro-vibration simulation platform

Abstract

The present invention discloses a six-degree-of-freedom micro-vibration simulation platform with flexible support, belonging to the technical field of ground simulation of space micro-vibration sources. The present invention includes an upper platform for carrying a load and a lower platform arranged below the upper platform and fixed in position; it also includes a plurality of support frames circumferentially distributed along the lower platform. The bottom end of the support frame is fixedly connected to the lower platform, and a motor is connected between the top end of the support frame and the upper platform to provide power for the vibration of the upper platform, and a plurality of flexible legs connected between the upper platform and the lower platform. The flexible leg includes a flexible beam folded along the length direction of the flexible leg, and both ends of the flexible beam are connected to the upper platform and the lower platform through flexible hinges. The present invention replaces the complex leg structure of the traditional simulator with a flexible beam of a folding structure, eliminates the frequency doubling phenomenon caused by the hinge clearance of the rigid hinge and the stiffness non-linearity of the spring strip, and has the beneficial effects of simple structure, easy manufacturing and convenient installation.

Description

Technical Field

[0001] The present invention relates to the technical field of ground simulation of space micro-vibration sources, and particularly to a six-degree-of-freedom micro-vibration simulation platform with flexible supports. Background Art

[0002] At present, with the development of high-resolution remote sensing satellites, the pointing accuracy and observation resolution of satellites are continuously improved, and various high-precision and high-sensitivity payloads carried by them have put forward higher and higher requirements for the micro-vibration environment of the platform. Therefore, the simulation of the micro-vibration environment is particularly important.

[0003] Since the Gough-Stewart platform has the characteristics of high stiffness, strong load capacity and high precision, most of the designs of multi-dimensional micro-vibration simulation platforms are based on the configuration of Gough-Stewart. This configuration platform consists of an upper platform, a lower platform and 6 complex legs. The legs are connected to the upper and lower platforms through rigid hinges. However, it is difficult to eliminate the clearance of the rigid hinges, and there is a problem of stiffness non-linearity of the spring plates in the legs. Therefore, frequency doubling phenomenon will occur during the test.

[0004] Therefore, carrying out the research on a new type of micro-vibration simulation platform, simplifying the leg structure and solving the frequency doubling phenomenon have very important engineering significance. Summary of the Invention

[0005] The object of the present invention is to overcome the defects existing in the prior art, and provide a six-degree-of-freedom micro-vibration simulation platform with flexible supports, which overcomes the problems such as hinge clearance of rigid hinges, stiffness non-linearity of spring plates in the legs and complex structure in the traditional space micro-vibration simulation platform. The present invention uses flexible hinges instead of rigid hinges and folding flexible beams instead of the spring plate structure in the traditional legs. This not only greatly simplifies the leg structure of the micro-vibration simulator, making its structure simple, easy to manufacture and convenient to install, but also can eliminate the frequency doubling phenomenon caused by the hinge clearance of rigid hinges and the stiffness non-linearity of spring plates.

[0006] In order to achieve the above object, the present invention provides the following technical solutions:

[0007] A six-degree-of-freedom micro-vibration simulation platform with flexible supports disclosed by the present invention includes:

[0008] An upper platform for carrying loads, and a lower platform disposed below the upper platform and fixed in position; and further includes

[0009] A plurality of support frames circumferentially distributed along the lower platform, the bottom ends of the support frames are fixedly connected to the lower platform, and motors are connected between the top ends of the support frames and the upper platform to provide power for the vibration of the upper platform, and

[0010] A plurality of flexible legs connected between the upper platform and the lower platform, the flexible legs including flexible beams folded along the length direction of the flexible legs, and both ends of the flexible beams being connected to the upper platform and the lower platform through flexible hinges.

[0011] Further, the flexible beam includes two vertical segments and a folding portion connected between the vertical segments and folded back and forth;

[0012] Wherein, the axes of the two vertical segments are collinear, the ends of the vertical segments away from the folding portion are connected to the flexible hinges, and the folding portion is formed on one side of the axis of the vertical segments.

[0013] Further, the folding portion includes a plurality of horizontal segments arranged in parallel and stacked in sequence;

[0014] The same ends of the horizontal segments at the top layer and the bottom layer of the folding portion are fixedly connected to the vertical segments, and wherein, adjacent two horizontal segments are connected end to end through connecting segments.

[0015] Further, the projected area of the upper platform on the horizontal plane is smaller than the projected area of the lower platform.

[0016] Further, there are three of the support frames. Among them, the motor includes a motor stator fixedly connected to the support frame and a motor rotor fixedly connected to the upper platform. The motor rotors are circumferentially distributed along the upper platform, and the included angle between adjacent two motor rotors is 120°.

[0017] Further, there are six flexible beams. Two of the six flexible beams are in a group and extend obliquely upward in an inverted V shape. The lower part of the support frame corresponds to the lower part of the motor stator and is fixedly connected to the bottom ends of a group of flexible beams through two flexible hinges. The top ends of the flexible beams are connected to the lower surface of the upper platform through the flexible hinges.

[0018] In the above technical solution, a six-degree-of-freedom micro-vibration simulation platform with flexible support provided by the present invention uses a motor to provide the power required when the upper platform vibrates. The legs use flexible beams with a folding structure instead of the spring sheets in traditional legs. While ensuring that the legs can expand and contract along their axial directions, it eliminates the frequency doubling phenomenon caused by the stiffness non-linearity of the spring sheets. The deformation of the flexible hinges and flexible beams can ensure that the upper platform can perform translational and rotational motions in three directions of X, Y, and Z. The fundamental frequency of the entire simulator is determined by the fundamental frequency of a single leg. By changing the thickness of the folded flexible beam and the number of horizontal segments of the folding portion, its flexibility is changed, thereby changing the fundamental frequency of the legs and the entire machine simulation platform;

[0019] The beneficial effects of this simulation platform:

[0020] 1) The folded flexible beam replaces the spring plate in the traditional complex outrigger, eliminating the frequency doubling phenomenon caused by the non-linearity of the spring plate stiffness;

[0021] 2) The flexible hinge replaces the rigid hinge, eliminating the frequency doubling phenomenon caused by the hinge clearance existing in the rigid hinge;

[0022] 3) The fundamental frequency of the entire micro-vibration simulation platform is better controlled, and only the thickness and the number of folds of the folded flexible beam need to be changed;

[0023] 4) The six-degree-of-freedom micro-vibration simulation platform has a simple and compact structure, is easy to design, manufacture, install, occupies a small space, and is conducive to transportation. Description of the Drawings

[0024] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required to be used in the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those of ordinary skill in the art, other drawings can also be obtained based on these drawings.

[0025] Figure 1 It is a schematic diagram of the overall structure of a six-degree-of-freedom micro-vibration simulation platform with flexible support disclosed by the present invention;

[0026] Figure 2 It is a top view of a six-degree-of-freedom micro-vibration simulation platform with flexible support disclosed by the present invention;

[0027] Figure 3 It is a schematic diagram of the structure of the flexible beam of a six-degree-of-freedom micro-vibration simulation platform with flexible support disclosed by the present invention.

[0028] Description of the Reference Numerals:

[0029] 1. Upper platform; 2. Motor mover; 3. Motor stator; 4. Flexible beam; 401. Vertical section; 402. Horizontal section; 403. Connection section; 5. Flexible hinge; 6. Support frame; 7. Lower platform. Detailed Embodiments

[0030] In order to enable those skilled in the art to better understand the technical solutions of the present invention, the following will further introduce the present invention in detail with reference to the drawings.

[0031] See Figure 1 as shown;

[0032] An invention relates to a six-degree-of-freedom micro-vibration simulation platform with flexible support, including:

[0033] An upper platform 1 for carrying a load, and a lower platform 7 arranged below the upper platform 1 and fixed in position;

[0034] Among them, it further includes a plurality of support frames 6 circumferentially distributed along the lower platform 7. The bottom end of the support frame 6 is fixedly connected to the lower platform 7, and a motor is connected between the top end of the support frame 6 and the upper platform 1 to provide the power for the vibration of the upper platform 1, and

[0035] a plurality of flexible legs connected between the upper platform 1 and the lower platform 7. The flexible leg includes a flexible beam 4 folded along the length direction of the flexible leg. Both ends of the flexible beam 4 are connected to the upper platform 1 and the lower platform 7 through flexible hinges 5.

[0036] Specifically, in this structure, the upper platform 1 is a moving platform for installing test loads, and the lower platform 7 is a fixed platform with a fixed position. The motor includes a motor mover 2 and a motor stator 3. The number of motors matches the number of support frames 6, both being three. The motor mover 2 is fixed on the side of the upper platform. The three motor movers 2 are circumferentially distributed along the upper platform 1, and the included angle between two adjacent motor movers 2 is 120°. The motor stator 3 is installed at the top end of the corresponding support frame 6. The bottom end of the support frame 6 is fixed to the lower platform 7 by screws. Six flexible legs are connected between the upper platform 1 and the lower platform 7. The flexible leg includes a flexible beam 4. A folding part folded along the length direction of the flexible leg is formed in the middle of the flexible beam 4. Both ends of the flexible beam 4 are respectively connected with a flexible hinge 5. The other end of the flexible hinge 5 is fixedly connected to the upper platform 1 and the lower platform 7 by screws. This structure replaces the rigid hinge in the prior art with a flexible hinge 5, eliminating the double-frequency phenomenon caused by the hinge clearance of the rigid hinge. The flexible beam 4 with a folding structure replaces the spring piece in the leg of the prior art, ensuring that the leg can expand and contract along its axis, and eliminating the double-frequency phenomenon caused by the stiffness non-linearity of multiple spring pieces. Moreover, the fundamental frequency of the entire simulation platform is determined by the fundamental frequency of a single flexible leg. The flexibility can be changed by changing the thickness of the flexible beam 5 with a folding structure, and the fundamental frequency of the leg and the entire machine simulation platform can be changed;

[0037] The six-degree-of-freedom micro-vibration simulation platform has a simple structure, is easy to manufacture and install. The flexible beam 4 with a folding structure replaces the complex leg structure of the traditional simulator, thus overcoming the problems of the influence caused by the hinge clearance of the rigid hinge and the stiffness non-linearity of the spring piece in the micro-vibration platform with the traditional structure;

[0038] Preferably, the flexible beam 4 includes two vertical segments 401 and a folding part that is folded back and forth between the vertical segments 401. Among them, the axes of the two vertical segments 401 are collinear. The end of the vertical segment 401 far from the folding part is connected to the flexible hinge 5, and the folding part is formed on one side of the axis of the vertical segment 401. That is to say, the folding part is offset to one side of the vertical segment 401, and the two flexible beams 4 in the same group are symmetrically arranged. This structure of the flexible beam 4 increases the flexibility of the flexible beam through the folding part, improves the bending stiffness of the platform, and can simulate a wider frequency band of micro-vibrations. The vertical segment 401 enables the connection between the flexible beam 4 and the flexible hinge 5 to be more convenient;

[0039] Preferably, the folding part includes a plurality of horizontal segments 402 which are arranged in parallel with each other and stacked in sequence;

[0040] The same ends of the horizontal segments 402 at the top and bottom of the folding part are fixedly connected to the vertical segments 401. Among them, adjacent two horizontal segments 402 are connected end to end through a connecting segment 403. This structure spaces adjacent two horizontal segments 402 through the connecting segment 403, which is beneficial to the flexible deformation of the folding part. Specifically, the number of horizontal segments 402 in the folding part, as well as the thicknesses of the vertical segments 401, horizontal segments 402, and connecting segments 403 can be selected according to design requirements. By changing the thickness of the flexible beam 4 of the folding structure and the number of horizontal segments 402 of the folding part, its flexibility is changed, thereby changing the fundamental frequency of the legs and the entire machine simulation platform;

[0041] Preferably, the projected area of the upper platform 1 on the horizontal plane is smaller than the projected area of the lower platform 7.

[0042] Preferably, there are six flexible beams 4. Two of the six flexible beams 4 are in a group and extend obliquely upward in an inverted V shape. The lower part of the support frame 6 corresponds to the lower part of the motor stator 3 and is connected to the bottom ends of a group of flexible beams 4 through two flexible hinges 5. The top ends of the flexible beams 4 are connected to the lower surface of the upper platform 1 through flexible hinges 5. Specifically, in this structure, the two flexible beams 4 in the same group extend obliquely in an inverted V shape towards the upper platform 1 and are symmetrically distributed on both sides of the axis of the motor stator 3. This structure effectively ensures the structural symmetry of the entire platform. More than three motors are distributed at 120° with the center of the upper platform 1 as the center, enabling the upper platform 1 to perform six-degree-of-freedom micro-vibration simulation;

[0043] In the above technical solution, the working process of a six-degree-of-freedom micro-vibration simulation platform with flexible support provided by the present invention;

[0044] When it is necessary to perform micro-vibration simulation on the upper platform 1, the motor stator 3 and motor rotor 2 of the motor start to work, driving the upper platform 1 to move. The flexible hinge 5 is deformed under the action of force, driving the flexible beam 4 to perform axial movement. The deformation of the flexible hinge 5 and the flexible beam 4 ensures that the upper platform 1 can perform translational and rotational motions in the X, Y, and Z directions;

[0045] This six-degree-of-freedom micro-vibration simulation platform with flexible support realizes the output of six-degree-of-freedom micro-vibration of the load platform. During its working process, by changing the input force magnitudes of the motor stator 3 and motor rotor 2, the vibration direction generated by the upper platform 1 is changed to meet the requirements of different test conditions for the micro-vibration direction.

[0046] Only certain exemplary embodiments of the present invention have been described above by way of illustration. Without doubt, for those of ordinary skill in the art, the described embodiments can be modified in various different ways without departing from the spirit and scope of the present invention. Therefore, the above drawings and description are illustrative in nature and should not be construed as limiting the scope of the claims of the present invention.

Claims

1. A six-degree-of-freedom micro-vibration simulation platform with flexible support, comprising: an upper platform (1) for carrying a load, and a lower platform (7) disposed below the upper platform (1) and having a fixed position, characterized in that; further comprising a plurality of support frames (6) circumferentially distributed along the lower platform (7), the bottom ends of the support frames (6) being fixedly connected to the lower platform (7), and a motor being connected between the top ends of the support frames (6) and the upper platform (1) for providing power for the vibration of the upper platform (1), and a plurality of flexible legs connected between the upper platform (1) and the lower platform (7), the flexible legs comprising flexible beams (4) folded along the length direction of the flexible legs, and both ends of the flexible beams (4) being connected to the upper platform (1) and the lower platform (7) through flexible hinges (5).

2. A six-degree-of-freedom micro-vibration simulation platform with flexible support according to claim 1, characterized in that; the flexible beam (4) comprises two vertical sections (401) and a folding portion connected between the vertical sections (401) and folded back and forth; wherein, the axes of the two vertical sections (401) are collinear, the ends of the vertical sections (401) far from the folding portion are connected to the flexible hinges (5), and the folding portion is formed on one side of the axis of the vertical sections (401).

3. A six-degree-of-freedom micro-vibration simulation platform with flexible support according to claim 2, characterized in that ； the folding portion comprises a plurality of horizontally arranged and sequentially stacked horizontal sections (402), the same ends of the topmost and bottommost horizontal sections (402) of the folding portion are fixedly connected to the vertical sections (401), and wherein, adjacent two horizontal sections (402) are connected end to end through connecting sections (403).

4. A six-degree-of-freedom micro-vibration simulation platform with flexible support according to claim 1, characterized in that ； the projected area of the upper platform (1) on the horizontal plane is smaller than the projected area of the lower platform (7).

5. A six-degree-of-freedom micro-vibration simulation platform with flexible support according to claim 1 or 4, characterized in that ； the support frames (6) comprise three, wherein, the motor comprises a motor stator (3) fixedly connected to the support frame (6) and a motor rotor (2) fixedly connected to the upper platform (1), the motor rotors (2) are circumferentially distributed along the upper platform (1), and the included angle between adjacent two motor rotors (2) is 120°.

6. A six-degree-of-freedom micro-vibration simulation platform with flexible support according to claim 5 ， characterized in that; the flexible beams (4) comprise six, and two of the six flexible beams (4) are in a group and extend obliquely upward in an inverted V shape, the lower part of the support frame (6) corresponding to the lower part of the motor stator (3) is connected to the bottom ends of a group of flexible beams (4) through two flexible hinges (5), and the top ends of the flexible beams (4) are connected to the lower surface of the upper platform (1) through the flexible hinges (5).

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