Pan-tilt vibration damper based on piezoelectric-shape memory alloy composite action

Abstract

The invention relates to a pan-tilt damping device based on piezoelectric-shape memory alloy composite action, which comprises a first-stage damping plate, a second-stage damping plate and a third-stage damping plate which are sequentially connected from top to bottom, and a piezoelectric stack is arranged between the first-stage damping plate and the second-stage damping plate. A shape memory alloy spring is arranged between the second-stage vibration reduction plate and the third-stage vibration reduction plate; the piezoelectric stack and the shape memory alloy spring are combined, reverse displacement is generated through the inverse piezoelectric effect of the piezoelectric stack, high-frequency vibration is counteracted in real time, and low-frequency vibration energy is dissipated through martensite reorientation in a phase-change temperature window through the shape memory alloy, so that the energy consumption is reduced, and the energy consumption is reduced. The damping structure is mounted between the unmanned aerial vehicle and airborne equipment, so that the unmanned aerial vehicle holder has a good damping effect in a relatively wide frequency domain.

Description

Technical Field

[0001] The present invention belongs to the field of semiconductor technology, and particularly relates to a pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy. Background Art

[0002] With the increasing maturity of unmanned aerial vehicle (UAV) technology, the load capacity and endurance of multi-rotor UAVs have been rapidly improved, and they are widely used in civil and military fields such as power inspection, aerial reconnaissance, and real-time target tracking and monitoring. Since UAVs are affected by their own airframe vibrations and large environmental interferences during flight, the vision system cannot clearly capture images and videos. In this system, the performance of the pan-tilt is particularly crucial for the stable operation of the vision system.

[0003] The UAV pan-tilt is a support device for UAVs to install and fix mission payloads such as cameras, and has the characteristics of material diversity and structural complexity. Its function is to isolate the influence of the carrier vibration and attitude maneuver on the imaging quality while achieving stable observation of specific targets, which can keep the long-focus camera in a stable position through the pan-tilt device in an unstable environment, minimizing the influence of external interferences on the obtained data or information.

[0004] Although the existing pan-tilt vibration damping structures can affect the overall vibration damping effect by changing the number, position distribution of vibration damping balls and the shape of the vibration damping plate, they have the following deficiencies:

[0005] Although traditional rubber vibration damping balls can reduce vibrations to a certain extent, their natural frequency suddenly rises under low-temperature working conditions, resulting in low-frequency resonance of the pan-tilt, which causes the vision system to be unable to clearly capture images and videos.

[0006] The stiffness of a single vibration damping element is fixed. In the low-frequency band, structural resonance is caused due to insufficient stiffness, and in the high-frequency band, the vibration transfer rate increases instead due to excessive stiffness.

[0007] Some pan-tilts adopt a static strength redundancy design in an attempt to improve stability, but it instead causes a series of negative effects. This approach not only increases the moment of inertia at various parts of the pan-tilt, but also causes the power consumption of the driving motor to rise, significantly shortening the endurance time of the UAV.

[0008] To solve the above problems, the present invention proposes a pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy. Summary of the Invention

[0009] To solve the above problems, the present invention provides a pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy, aiming to improve the vibration damping effect of the pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy.

[0010] To achieve the above object, the present invention provides the following solutions:

[0011] A pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy includes a first-stage damping plate, a second-stage damping plate, and a third-stage damping plate connected in sequence from top to bottom. A piezoelectric stack is arranged between the first-stage damping plate and the second-stage damping plate, and a shape memory alloy spring is arranged between the second-stage damping plate and the third-stage damping plate.

[0012] Preferably, piezoelectric stack limiting grooves are provided at corresponding positions on the lower surface of the first-stage damping plate and the upper surface of the second-stage damping plate, and both ends of the piezoelectric stack are respectively arranged in the piezoelectric stack limiting grooves of the first-stage damping plate and the second-stage damping plate.

[0013] Preferably, the piezoelectric stack limiting grooves are evenly spaced and circumferentially arranged around the centers of the first-stage damping plate and the second-stage damping plate where they are located.

[0014] Preferably, the first-stage damping plate and the second-stage damping plate are connected by bolts.

[0015] Preferably, shape memory alloy spring limiting grooves are provided at corresponding positions on the lower surface of the second-stage damping plate and the upper surface of the third-stage damping plate, and both ends of the shape memory alloy spring are respectively arranged in the shape memory alloy spring limiting grooves of the second-stage damping plate and the third-stage damping plate.

[0016] Preferably, the shape memory alloy spring limiting grooves are evenly spaced and circumferentially arranged around the centers of the second-stage damping plate and the third-stage damping plate where they are located.

[0017] Preferably, the second-stage damping plate and the third-stage damping plate are connected by a damping ball. The damping ball includes a rubber sphere and connecting plates respectively arranged on the upper surface of the second-stage damping plate and the lower surface of the third-stage damping plate. The two connecting plates are tied by a connecting piece, and the sphere is clamped between the connecting plates.

[0018] Preferably, a heating film is sleeved on the outer wall of the shape memory alloy spring.

[0019] Preferably, the depth of the shape memory alloy spring limiting groove is 0.5 mm to 0.6 mm, and an assembly gap of 0.1 mm to 0.15 mm is provided between both ends of the shape memory alloy spring and the shape memory alloy spring limiting groove.

[0020] Preferably, the shape memory alloy spring and the shape memory alloy spring limiting groove are bonded by high-temperature glue.

[0021] The present invention has achieved the following technical effects compared with the prior art:

[0022] The present invention combines a piezoelectric stack and a shape memory alloy spring. The reverse piezoelectric effect of the piezoelectric stack generates a reverse displacement to cancel high-frequency vibrations in real time, while the low-frequency vibration energy is dissipated through the reorientation of martensite within the phase transformation temperature window of the shape memory alloy. By installing the structure of the present invention between the drone and the on-board equipment, the drone gimbal can have a good vibration damping effect in a wide frequency range. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 are the three views of the present invention;

[0025] Figure 2 is the exploded view of the present invention;

[0026] Figure 3 is the schematic diagram of the lower surface structure of the first-stage vibration damping plate of the present invention;

[0027] Figure 4 is the schematic diagram of the upper surface structure of the second-stage vibration damping plate of the present invention;

[0028] Figure 5 is the schematic diagram of the lower surface structure of the second-stage vibration damping plate of the present invention;

[0029] Figure 6 is the schematic diagram of the upper surface structure of the third-stage vibration damping plate of the present invention;

[0030] Among them, 1, the first-stage vibration damping plate; 2, the second-stage vibration damping plate; 3, the third-stage vibration damping plate; 4, the piezoelectric stack; 5, the shape memory alloy spring; 6, the heating film; 7, the vibration damping ball; 8, the bolt; 9, the piezoelectric stack limiting groove; 10, the shape memory alloy spring limiting groove. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, rather than all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present invention.

[0032] To solve the above problems, the present invention provides a pan-tilt damping device based on the combined action of piezoelectric and shape memory alloy, aiming to improve the damping effect of the pan-tilt damping device based on the combined action of piezoelectric and shape memory alloy.

[0033] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0034] Reference Figures 1 to 6 , a pan-tilt damping device based on the combined action of piezoelectric and shape memory alloy, includes a first-stage damping plate 1, a second-stage damping plate 2, and a third-stage damping plate 3 connected in sequence from top to bottom. A piezoelectric stack 4 is arranged between the first-stage damping plate 1 and the second-stage damping plate 2, and a shape memory alloy spring 5 is arranged between the second-stage damping plate 2 and the third-stage damping plate 3. The present invention combines a piezoelectric stack and a shape memory alloy spring 5. The reverse piezoelectric effect of the piezoelectric stack 4 generates a reverse displacement to cancel high-frequency vibrations in real time, while the low-frequency vibration energy is dissipated through the martensite reorientation of the shape memory alloy spring 5 within the phase change temperature window. By installing the structure of the present invention between the drone and the airborne equipment, the drone pan-tilt can have good damping effects in a relatively wide frequency range.

[0035] Furthermore, the present invention actively identifies low-frequency or high-frequency vibration signals through an acceleration sensor, generates a reverse displacement through the reverse piezoelectric effect of the piezoelectric stack 4 to cancel high-frequency vibrations in real time, while the low-frequency vibration energy is dissipated through the martensite reorientation of the shape memory alloy spring 5 within the phase change temperature window. By installing this structure between the drone and the airborne equipment, the drone pan-tilt can have good damping effects in a relatively wide frequency range.

[0036] Reference Figures 2 to 6 , the first-stage damping plate 1, the second-stage damping plate 2, and the third-stage damping plate 3 are all circularly hollowed out in the middle. Among them, the second-stage damping plate 2 and the third-stage damping plate 3 have the same shape and size, which are quadrilateral, and the area of the first-stage damping plate 1 is smaller than that of the second-stage damping plate 2 and the third-stage damping plate 3, and the first-stage damping plate 1 is hexagonal.

[0037] Reference Figures 3 to 4 , piezoelectric stack limiting grooves 9 are provided at corresponding positions on the lower surface of the first-stage damping plate 1 and the upper surface of the second-stage damping plate 2. Both ends of the piezoelectric stack 4 are respectively arranged in the piezoelectric stack limiting grooves 9 of the first-stage damping plate 1 and the second-stage damping plate 2. Further, the piezoelectric stack limiting grooves 9 can be provided with two groups of different radii (6 in each group) arranged in a circumferential array along the center of the circle, and the depth is 0.3 mm.

[0038] Reference Figure 2, the piezoelectric stack limiting grooves 9 are evenly arranged circumferentially at equal intervals with the centers of the corresponding first-stage damping plate 1 and second-stage damping plate 2 as the centers; the purpose is that when the piezoelectric stack 4 generates reverse displacement due to the inverse piezoelectric effect, high-frequency vibrations can be evenly and efficiently cancelled out in real time.

[0039] Reference Figure 2 , the first-stage damping plate 1 and the second-stage damping plate 2 are connected by bolts 8, which is convenient for disassembly.

[0040] Reference Figures 5 to 6 , at the corresponding positions on the lower surface of the second-stage damping plate 2 and the upper surface of the third-stage damping plate 3, shape memory alloy spring limiting grooves 10 are provided, and both ends of the shape memory alloy spring 5 are respectively arranged in the shape memory alloy spring limiting grooves 10 of the second-stage damping plate 2 and the third-stage damping plate 3.

[0041] Reference Figure 2 , the shape memory alloy spring limiting grooves 10 are evenly arranged circumferentially at equal intervals with the centers of the corresponding second-stage damping plate 2 and third-stage damping plate 3 as the centers; the purpose is to ensure the uniformity when the shape memory alloy spring 5 dissipates energy during the martensite reorientation within the phase transition temperature window.

[0042] Reference Figure 2 , the second-stage damping plate 2 and the third-stage damping plate 3 are connected by damping balls 7. The damping balls 7 include rubber spheres and connecting plates respectively arranged on the upper surface of the second-stage damping plate 2 and the lower surface of the third-stage damping plate 3. The two connecting plates are tied together by connecting members, and the sphere is clamped between the connecting plates; generally, materials with damping effects such as rubber are selected for the sphere.

[0043] Reference Figure 2 , a heating film 6 is sleeved on the outer wall of the shape memory alloy spring 5, and the purpose is to limit the lateral deformation of the shape memory alloy spring 5.

[0044] Further, the depth of the shape memory alloy spring limiting groove 10 is 0.5 mm to 0.6 mm, and an assembly gap of 0.1 mm to 0.15 mm is provided between both ends of the shape memory alloy spring 5 and the shape memory alloy spring limiting groove 10.

[0045] Further, the shape memory alloy spring 5 and the shape memory alloy spring limiting groove 10 are bonded by high-temperature glue.

[0046] Adaptations made according to actual needs are all within the protection scope of the present invention.

[0047] It should be noted that for those skilled in the art, it is obvious that the present invention is not limited to the details of the above-described exemplary embodiments, and the present invention can be implemented in other specific forms without departing from the spirit or basic characteristics of the present invention. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present invention is defined by the appended claims rather than the above description. Therefore, all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be embraced within the invention. Any reference signs in the claims should not be construed as limiting the claims involved.

Claims

1. A pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy, characterized in that, It includes a first-level vibration damping plate, a second-level vibration damping plate, and a third-level vibration damping plate connected in sequence from top to bottom. A piezoelectric stack is arranged between the first-level vibration damping plate and the second-level vibration damping plate, and a shape memory alloy spring is arranged between the second-level vibration damping plate and the third-level vibration damping plate.

2. The pan-tilt vibration damping device based on the combined action of piezoelectricity and shape memory alloy according to claim 1, characterized in that Piezoelectric stack limiting grooves are arranged at corresponding positions on the lower surface of the first-level vibration damping plate and the upper surface of the second-level vibration damping plate. Both ends of the piezoelectric stack are respectively arranged in the piezoelectric stack limiting grooves of the first-level vibration damping plate and the second-level vibration damping plate.

3. The pan-tilt damping device based on the combined action of piezoelectricity and shape memory alloy according to claim 2, characterized in that, The piezoelectric stack limiting grooves are arranged circumferentially at uniform intervals with the centers of the first-level vibration damping plate and the second-level vibration damping plate where they are located as the centers.

4. The pan-tilt shock-absorbing device based on the combined action of piezoelectric and shape memory alloy according to claim 3, characterized in that, The first-level vibration damping plate and the second-level vibration damping plate are connected by bolts.

5. The pan-tilt damping device based on the combined action of piezoelectric and shape memory alloy according to claim 1, characterized in that, Shape memory alloy spring limiting grooves are arranged at corresponding positions on the lower surface of the second-level vibration damping plate and the upper surface of the third-level vibration damping plate. Both ends of the shape memory alloy spring are respectively arranged in the shape memory alloy spring limiting grooves of the second-level vibration damping plate and the third-level vibration damping plate.

6. The pan-tilt shock-absorbing device based on the combined action of piezoelectricity and shape memory alloy according to claim 5, characterized in that The shape memory alloy spring limiting grooves are arranged circumferentially at uniform intervals with the centers of the second-level vibration damping plate and the third-level vibration damping plate where they are located as the centers.

7. The pan-tilt vibration damping device based on the combined action of piezoelectric and shape memory alloy according to claim 6, characterized in that, The second-level vibration damping plate and the third-level vibration damping plate are connected by a vibration damping ball. The vibration damping ball includes a rubber sphere and connecting plates respectively arranged on the upper surface of the second-level vibration damping plate and the lower surface of the third-level vibration damping plate. The two connecting plates are tied by a connecting piece, and the sphere is clamped between the connecting plates.

8. The pan-tilt damping device based on the combined action of piezoelectric and shape memory alloy according to claim 6, characterized in that A heating film is sleeved on the outer wall of the shape memory alloy spring.

9. The pan-tilt shock-absorbing device based on the combined action of piezoelectricity and shape memory alloy according to claim 6, characterized in that, The depth of the shape memory alloy spring limiting groove is 0.5 mm to 0.6 mm, and an assembly gap of 0.1 mm to 0.15 mm is provided between both ends of the shape memory alloy spring and the shape memory alloy spring limiting groove.

10. The pan-tilt damping device based on the combined action of piezoelectric and shape memory alloy according to claim 9, characterized in that The shape memory alloy spring and the shape memory alloy spring limiting groove are bonded by high-temperature glue.

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