Three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite driving

Abstract

The invention relates to a three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite driving. The three-degree-of-freedom parallel platform mainly comprises a base, a movable platform and three low-medium-high frequency composite driving branch chains which are uniformly distributed between the base and the movable platform and have the same structure, the low-medium-high frequency composite driving branch chain is formed by connecting and hinging a low-medium-high frequency composite driving unit and a mixed output component in series, the low-medium-high frequency composite driving unit is connected with the base, and the mixed output component is hinged to the movable platform; the low-medium-high frequency composite drive unit comprises a low-frequency drive, a medium-frequency drive and a high-frequency drive, and can realize composite drive output across three frequency bands. The method can be applied to the field of stabilized platforms in a cross-frequency-band disturbance environment, and three-degree-of-freedom mixed-frequency-band motion output is realized based on a low-frequency, intermediate-frequency and high-frequency composite driving mode.

Description

Technical Field

[0001] The invention relates to a three-degree-of-freedom parallel platform, in particular to a three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite driving. Background Art

[0002] In the process of aerospace, offshore operations, ambulance medical treatment, etc., in order to ensure the stable operation of precision instruments on the carrier, a stable platform is needed to perform real-time reverse compensation for the multi-dimensional disturbance forms of the surrounding environment. The disturbance form can be divided into high-frequency disturbance, medium-frequency disturbance and low-frequency disturbance according to the frequency band. The existing stable platform is limited by the frequency bandwidth of the driver, and it is difficult to achieve low-medium-high frequency real-time motion output.

[0003] Patent CN107225562B proposes a two-turn one-shift three-degree-of-freedom attitude adjustment vibration isolation platform with high- and low-frequency dual drive units. The invention can realize the two-turn one-shift mixed output of dual-frequency band drive, and has a good vibration isolation effect on high-frequency vibration, but its attitude adjustment range is limited, which limits its application scope; Patent CN104390755A proposes a three-degree-of-freedom high- and low-frequency composite drive parallel three-degree-of-freedom motion platform. The invention can provide different types of high- and low-frequency three-degree-of-freedom output forms according to different application requirements, but is limited by its dual drive unit form and cannot achieve the composite output of three-frequency band drive; Patent CN104308838A proposes a high- and low-frequency composite drive six-degree-of-freedom parallel motion platform. The invention needs to add twelve drives, and has a weak ability to suppress high-frequency vibrations, and does not achieve the rational use of vibration isolation resources. Therefore, how to solve the limited attitude adjustment range and realize the composite output and vibration isolation of three-frequency band drive is a technical problem that needs to be solved urgently. Summary of the invention

[0004] In response to the above problems, the purpose of the present invention is to provide a three-degree-of-freedom parallel platform that can realize low-medium-high frequency composite drive, which can realize three-degree-of-freedom mixed frequency band motion output based on a composite drive mode of low frequency, medium frequency and high frequency according to the requirements of cross-frequency band disturbance isolation.

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: a three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive, comprising a base, a moving platform and three low-medium-high frequency composite drive branches with the same structure uniformly distributed between the base and the moving platform: the base is a Y-shaped structure composed of three completely identical branch bases, and each branch base is uniformly distributed about the center line of the base; the low-medium-high frequency composite drive branch is formed by hingedly connecting a low-medium-high frequency composite drive unit and a hybrid output component in series, and the center lines of all components are in the same plane, one end of the low-medium-high frequency composite drive unit is fixedly connected to the branch base of the base, and the other end is connected to the hybrid output component through a sixth rotation pair; the moving platform is hingedly connected to the hybrid output component of the low-medium-high frequency composite drive branch through a first spherical pair, and can realize a three-degree-of-freedom hybrid frequency segment motion output; or, the first spherical pair is replaced by three orthogonal rotation pairs with overlapping hinge points.

[0006] Further, the low-medium-high frequency composite drive unit includes a low frequency drive component, a medium frequency drive component, a high frequency drive component, a composite output rod, and / or a medium frequency transmission rod, and / or a medium and high frequency transmission rod, and / or a low frequency transmission rod.

[0007] Furthermore, the specific structural form of the low-medium-high frequency composite drive unit is as follows: two ends of the low frequency drive component are respectively hinged to the base and the composite output rod through the first rotation pair and the seventh rotation pair, the medium frequency drive component and the high frequency drive component are fixedly connected to the base, one end of the medium frequency transmission rod and the medium and high frequency transmission rod are respectively hinged to the medium frequency drive component and the high frequency drive component through the second rotation pair and the third rotation pair, the other end of the medium frequency transmission rod is connected to the rod body of the medium and high frequency transmission rod through the fourth rotation pair, and the other end of the medium and high frequency transmission rod is hinged to the composite output rod through the fifth rotation pair.

[0008] Furthermore, the specific structural form of the low-medium-high frequency composite drive unit is as follows: the low-frequency drive component, the medium-frequency drive component and the high-frequency drive component fixedly connected to the base are respectively hinged to the low-frequency transmission rod, the medium-frequency transmission rod and the medium-high frequency transmission rod through the first rotating pair, the second rotating pair and the third rotating pair, the other end of the low-frequency transmission rod is hinged to the composite output rod through the seventh rotating pair, the other end of the medium-frequency transmission rod is hinged to the rod body of the medium-high frequency transmission rod through the fourth rotating pair, and the other end of the medium-high frequency transmission rod is hinged to the composite output rod through the fifth rotating pair.

[0009] Furthermore, the specific structural form of the low-medium-high frequency composite drive unit is as follows: the low-frequency drive component, the medium-frequency drive component and the high-frequency drive component are respectively hinged to the base through the first rotation pair, the second rotation pair and the third rotation pair, the other end of the low-frequency drive component is hinged to the composite output rod through the seventh rotation pair, the other end of the medium-frequency drive component is hinged to the rod body of the high-frequency drive component through the fourth rotation pair, and the other end of the high-frequency drive component is hinged to the composite output rod through the fifth rotation pair.

[0010] Further, in the low-medium-high frequency composite drive unit, the low frequency drive component, the high frequency drive component, the composite output rod, and / or the medium and high frequency transmission rod, and / or the low frequency transmission rod, the first rotating pair, the third rotating pair, the fifth rotating pair and the seventh rotating pair constitute a planar six-rod closed-loop structure; the medium frequency drive component, the high frequency drive component, and / or the medium frequency transmission rod, and / or the medium and high frequency transmission rod, the second rotating pair, the third rotating pair and the fourth rotating pair constitute a planar five-rod closed-loop structure; the overall structural form of the low-medium-high frequency composite drive unit is a planar multi-closed-loop mechanism with three degrees of freedom, which can correspond to the composite output motions of the three frequency bands of the low frequency drive component, the medium frequency drive component and the high frequency drive component respectively.

[0011] Furthermore, the low-frequency drive component, the medium-frequency drive component and the high-frequency drive component select hydraulic, motor or pneumatic drive forms according to actual needs; the transmission form of the low-frequency drive component, the medium-frequency drive component and the high-frequency drive component selects mechanical transmission, hydraulic transmission and / or electric transmission according to actual needs.

[0012] The present invention adopts the above technical solution, which has the following advantages:

[0013] 1. The present invention adopts a low, medium and high frequency hybrid driving form. Through the effective combination of three driving multiple input forms, disturbance isolation across three frequency bands can be achieved, broadening the application scope of the existing parallel stabilization platform.

[0014] 2. The present invention arranges each frequency driver close to one side of the base to ensure that no additional load is generated between the drivers, thereby maximizing the carrying capacity of the platform.

[0015] 3. The present invention realizes stable output of 3 degrees of freedom through 9 drives, so that the parallel platform has multiple combinations when realizing a movement, which can effectively improve environmental adaptability. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a three-dimensional schematic diagram of embodiment 1 of the present invention;

[0017] Figure 2 This is a schematic diagram of a single branch plane of Example 1 of the present invention;

[0018] Figure 3 This is a schematic diagram of a single branch plane of Example 2 of the present invention;

[0019] Figure 4 This is a schematic diagram of a single branch plane of Example 3 of the present invention;

[0020] Figure numerals: 1, base; 2, low-frequency driving component; 3, medium-frequency driving component; 4, high-frequency driving component; 5, medium-frequency transmission rod; 6, medium-high frequency transmission rod; 7, composite output rod; 8, mixed output component; 9, moving platform; 10, low-frequency transmission rod; R1, first rotation pair; R2, second rotation pair; R3, third rotation pair; R4, fourth rotation pair; R5, fifth rotation pair; R6, sixth rotation pair; R7, seventh rotation pair; S1, first spherical pair. DETAILED DESCRIPTION

[0021] In order to broaden the application scope of the stable platform, realize disturbance isolation across three frequency bands, and correspond to the motion output of the three main degrees of freedom of pitch, yaw and heave, and overcome the problems of limited attitude adjustment and inability to realize the composite output of three-frequency band drive in the prior art, the present invention provides a three-degree-of-freedom parallel platform that can realize low-medium-high frequency composite drive, which includes a base, a moving platform and three low-medium-high frequency composite drive branches with the same structure connecting the base and the moving platform, and the three composite drive branches are evenly distributed on the base and the moving platform; the low-medium-high frequency composite drive branch is composed of a low-medium-high frequency composite drive unit and a mixed output component in series, wherein the low-medium-high frequency composite drive unit is connected to the base, and the two ends of the mixed output component are respectively hinged to the moving platform and the low-medium-high frequency composite drive unit. The present invention can realize the three-degree-of-freedom mixed frequency band motion output based on the composite drive mode of low frequency, medium frequency and high frequency according to application requirements.

[0022] In order to make the purpose, technical solution and advantages of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field belong to the scope of protection of the present invention.

[0023] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0024] The present invention provides a three-degree-of-freedom parallel platform that can realize low-medium-high frequency composite drive. Figure 1 As shown, the three-degree-of-freedom parallel platform includes: a base 1, a moving platform 9, and three low-medium-high frequency composite drive branches with the same structure uniformly distributed between the base 1 and the moving platform 9: the base 1 is a Y-shaped structure composed of three completely identical branch bases, and each branch base is uniformly distributed about the center line of the base; the low-medium-high frequency composite drive branch is formed by hingedly connecting a low-medium-high frequency composite drive unit and a mixed output component 8 in series, and the center lines of all components are in the same plane, one end of the low-medium-high frequency composite drive unit is fixedly connected to the branch base of the base 1, and the other end is connected to the mixed output component 8 through the sixth rotation pair R6; the moving platform 9 is hingedly connected to the mixed output component 8 of the low-medium-high frequency composite drive branch through the first spherical pair S1, so as to realize the mixed frequency segment motion output of three degrees of freedom; wherein, the first spherical pair S1 can be replaced by three orthogonal rotation pairs with overlapping hinge points.

[0025] Specifically, the low-medium-high frequency composite drive unit includes a low frequency drive component 2, a medium frequency drive component 3, a high frequency drive component 4, a composite output rod 7, and / or a medium frequency transmission rod 5, and / or a medium and high frequency transmission rod 6, and / or a low frequency transmission rod 10.

[0026] Specifically, the low-frequency drive component 2, the medium-frequency drive component 3 and the high-frequency drive component 4 can select hydraulic, motor or pneumatic drive forms according to actual needs, including but not limited to electromagnetic actuators, electro-hydraulic actuators, voice coil motors, high-frequency linear motors, piezoelectric ceramic actuators, piezoelectric film actuators, electrostrictive actuators, magnetostrictive actuators, shape memory alloy actuators, servo actuators and electrorheological fluid actuators, etc.; the transmission forms of the low-frequency drive component 2, the medium-frequency drive component 3 and the high-frequency drive component 4 can also be selected according to actual needs. Mechanical transmission, hydraulic transmission, electric transmission, including but not limited to ball screws, movable guides and belt transmissions, etc.

[0027] Embodiment 1:

[0028] like Figure 1 , 2As shown, the low-medium-high frequency composite drive unit comprises a low frequency drive component 2, a medium frequency drive component 3, a high frequency drive component 4, a medium frequency transmission rod 5, a medium and high frequency transmission rod 6 and a composite output rod 7. The two ends of the low frequency drive component 2 are respectively hinged to the base 1 and the composite output rod 7 through the first rotation pair R1 and the seventh rotation pair R7, the medium frequency drive component 3 and the high frequency drive component 4 are fixedly connected to the base 1, one end of the medium frequency transmission rod 5 and the medium and high frequency transmission rod 6 are respectively hinged to the medium frequency drive component 3 and the high frequency drive component 4 through the second rotation pair R2 and the third rotation pair R3, the other end of the medium frequency transmission rod 5 is connected to the rod body of the medium and high frequency transmission rod 6 through the fourth rotation pair R4, and the other end of the medium and high frequency transmission rod 6 is hinged to the composite output rod 7 through the fifth rotation pair R5.

[0029] The overall structural form of the low-medium-high frequency composite drive unit is a planar multi-closed loop mechanism with three degrees of freedom, which can correspond to the composite drive of the three frequency bands of the low-frequency drive component 2, the medium-frequency drive component 3 and the high-frequency drive component 4 respectively, and realize the mixed motion output of three different frequencies and different amplitudes. Combined with the motion transmission of the mixed output component 8 and the arrangement between the branches, the output form of the three-degree-of-freedom mixed motion of two rotations and one movement of the moving platform 9 can be realized.

[0030] Embodiment 2:

[0031] like Figure 3 As shown, the low-medium-high frequency composite drive unit includes a low-frequency drive component 2, a medium-frequency drive component 3, a high-frequency drive component 4, a medium-frequency transmission rod 5, a medium-high frequency transmission rod 6, a low-frequency transmission rod 10 and a composite output rod 7. The low-frequency drive component 2, the medium-frequency drive component 3 and the high-frequency drive component 4 fixed to the base 1 are respectively hinged with the low-frequency transmission rod 10, the medium-frequency transmission rod 5 and the medium-high frequency transmission rod 6 through the first rotation pair R1, the second rotation pair R2, and the third rotation pair R3. The other end of the low-frequency transmission rod 10 is hinged with the composite output rod 7 through the seventh rotation pair R7, the other end of the medium-frequency transmission rod 5 is hinged with the rod body of the medium-high frequency transmission rod 6 through the fourth rotation pair R4, and the other end of the medium-high frequency transmission rod 6 is hinged with the composite output rod 7 through the fifth rotation pair R5. Compared with embodiment 1, this embodiment has better bearing performance, but occupies more space, and can be reasonably selected according to actual needs.

[0032] Embodiment 3:

[0033] like Figure 4As shown, the low-medium-high frequency composite drive unit includes a low-frequency drive component 2, a medium-frequency drive component 3, a high-frequency drive component 4 and a composite output rod 7. The low-frequency drive component 2, the medium-frequency drive component 3 and the high-frequency drive component 4 are respectively hinged to the base 1 through the first rotation pair R1, the second rotation pair R2 and the third rotation pair R3, the other end of the low-frequency drive component 2 is hinged to the composite output rod 7 through the seventh rotation pair R7, the other end of the medium-frequency drive component 3 is hinged to the rod body of the high-frequency drive component 4 through the fourth rotation pair R4, and the other end of the high-frequency drive component 4 is hinged to the composite output rod 7 through the fifth rotation pair R5. Compared with embodiment 1 and embodiment 2, this embodiment has poor bearing performance, but high driving sensitivity and smaller space, and can be reasonably selected according to actual needs.

[0034] In the above embodiments, in the low-medium-high frequency composite drive unit, the low frequency drive component 2, the high frequency drive component 4, the composite output rod 7, and / or the medium and high frequency transmission rod 6, and / or the low frequency transmission rod 10, the first rotation pair R1, the third rotation pair R3, the fifth rotation pair R5 and the seventh rotation pair R7 constitute a planar six-bar closed loop structure; the medium frequency drive component 3, the high frequency drive component 4, and / or the medium frequency transmission rod 5, and / or the medium and high frequency transmission rod 6, the second rotation pair R2, the third rotation pair R3 and the fourth rotation pair R4 constitute a planar five-bar closed loop structure; the overall structural form of the low-medium-high frequency composite drive unit is a planar multi-closed loop mechanism with three degrees of freedom, which can correspond to the composite output motions of the three frequency bands of the low frequency drive component 2, the medium frequency drive component 3 and the high frequency drive component 4 respectively.

[0035] In the above embodiments, the operating frequency range of the low-frequency drive component 2 can be set to 0-1KHz, the operating frequency range of the medium-frequency drive component 3 can be set to 1KHz-12KHz, and the operating frequency range of the high-frequency drive component 4 can be set to be higher than 100KHz. When the present invention is used, the low-frequency drive component 2, the medium-frequency drive component 3 and the high-frequency drive component 4 work independently and do not affect each other, and disturbance isolation across three frequency bands can be achieved. The present invention realizes the stable output of three degrees of freedom of two rotations and one translation of the moving platform 9 through 9 drive motors, so that the parallel platform has a variety of combinations when realizing a certain determined movement, which can effectively improve environmental adaptability.

[0036] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive, characterized in that: It comprises a base (1), a moving platform (9), and three low-medium-high frequency composite drive branches with the same structure evenly distributed between the base and the moving platform: The base (1) is a Y-shaped structure consisting of three identical branch bases, and each branch base is evenly distributed about the center line of the base; The low-medium-high frequency composite drive branch chain is formed by a low-medium-high frequency composite drive unit and a mixed output component (8) being hinged in series, and the center lines of all components are in the same plane, one end of the low-medium-high frequency composite drive unit is fixedly connected to the branch base of the base (1), and the other end is connected to the mixed output component (8) through a sixth rotation pair (R6); The moving platform (9) is hinged to the mixed output component (8) of the low-medium-high frequency composite drive branch chain through a first spherical pair (S1), so as to realize a mixed frequency range motion output with three degrees of freedom; or, the first spherical pair (S1) is replaced by three orthogonal rotation pairs with overlapping hinge points.

2. A three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive as claimed in claim 1, characterized in that: The low-medium-high frequency composite drive unit comprises a low frequency drive component (2), a medium frequency drive component (3), a high frequency drive component (4), a composite output rod (7), and / or a medium frequency transmission rod (5), and / or a medium and high frequency transmission rod (6), and / or a low frequency transmission rod (10).

3. A three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive as claimed in claim 2, characterized in that: The specific structural form of the low-medium-high frequency composite drive unit is as follows: two ends of the low frequency drive component (2) are respectively hinged to the base (1) and the composite output rod (7) through a first rotational pair (R1) and a seventh rotational pair (R7); the medium frequency drive component (3) and the high frequency drive component (4) are fixedly connected to the base (1); one end of the medium frequency transmission rod (5) and the medium and high frequency transmission rod (6) are respectively hinged to the medium frequency drive component (3) and the high frequency drive component (4) through a second rotational pair (R2) and a third rotational pair (R3); the other end of the medium frequency transmission rod (5) is connected to the rod body of the medium and high frequency transmission rod (6) through a fourth rotational pair (R4); and the other end of the medium and high frequency transmission rod (6) is hinged to the composite output rod (7) through a fifth rotational pair (R5).

4. A three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive as claimed in claim 2, characterized in that: The specific structural form of the low-medium-high frequency composite drive unit is as follows: the low-frequency drive component (2), the medium-frequency drive component (3) and the high-frequency drive component (4) fixedly connected to the base (1) are respectively hinged to the low-frequency transmission rod (10), the medium-frequency transmission rod (5) and the medium-high frequency transmission rod (6) through a first rotational pair (R1), a second rotational pair (R2) and a third rotational pair (R3); the other end of the low-frequency transmission rod (10) is hinged to the composite output rod (7) through a seventh rotational pair (R7); the other end of the medium-frequency transmission rod (5) is hinged to the rod body of the medium-high frequency transmission rod (6) through a fourth rotational pair (R4); and the other end of the medium-high frequency transmission rod (6) is hinged to the composite output rod (7) through a fifth rotational pair (R5).

5. A three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive as claimed in claim 2, characterized in that: The specific structural form of the low-medium-high frequency composite drive unit is as follows: the low-frequency drive component (2), the medium-frequency drive component (3) and the high-frequency drive component (4) are respectively hinged to the base (1) through a first rotational pair (R1), a second rotational pair (R2) and a third rotational pair (R3); the other end of the low-frequency drive component (2) is hinged to the composite output rod (7) through a seventh rotational pair (R7); the other end of the medium-frequency drive component (3) is hinged to the rod body of the high-frequency drive component (4) through a fourth rotational pair (R4); and the other end of the high-frequency drive component (4) is hinged to the composite output rod (7) through a fifth rotational pair (R5).

6. The three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive according to any one of claims 2 to 5, characterized in that: In the low-medium-high frequency composite drive unit, the low frequency drive component (2), the high frequency drive component (4), the composite output rod (7), and / or the medium-high frequency transmission rod (6), and / or the low frequency transmission rod (10), the first rotational pair (R1), the third rotational pair (R3), the fifth rotational pair (R5) and the seventh rotational pair (R7) form a planar six-rod closed loop structure; the medium frequency drive component (3), the high frequency drive component (4), and / or the medium frequency transmission rod (5), and / or the medium-high frequency transmission rod (6), the second rotational pair (R2), the third rotational pair (R3) and the fourth rotational pair (R4) form a planar five-rod closed loop structure; the overall structural form of the low-medium-high frequency composite drive unit is a planar multi-closed loop mechanism, which has three degrees of freedom and can correspond to the composite output motions of the three frequency bands of the low frequency drive component (2), the medium frequency drive component (3) and the high frequency drive component (4).

7. The three-degree-of-freedom parallel platform capable of realizing low-medium-high frequency composite drive as claimed in claim 6, characterized in that: The low-frequency drive component (2), the medium-frequency drive component (3) and the high-frequency drive component (4) are selected from hydraulic, motor or pneumatic drive forms according to actual needs; the transmission forms of the low-frequency drive component (2), the medium-frequency drive component (3) and the high-frequency drive component (4) are selected from mechanical transmission, hydraulic transmission and / or electric transmission according to actual needs.

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