Umbrella-shaped unfolding and folding mechanism based on shape memory alloy and spacecraft

Abstract

The invention provides an umbrella-shaped unfolding and folding mechanism based on shape memory alloy and a spacecraft, and relates to the technical field of spaceflight equipment.The umbrella-shaped unfolding and folding mechanism based on the shape memory alloy comprises a first pipe body, a second pipe body, a base, a tensioning lock net, a radiation rib, an SMA driving spring, a propelling plate, a sliding block and a power source; the first pipe body sleeves the second pipe body, and the lower ends of the first pipe body and the second pipe body are respectively connected with the base; the power supply is arranged in the base and is electrically connected with the SMA driving spring; a window communicating with the gap is formed in the second pipe body, the pushing plate is hinged to the window, and the sliding block is slidably connected to the inner wall of the second pipe body; the multiple radiation ribs are arranged around the first pipe body at intervals, one end of each radiation rib is hinged to the base, and each radiation rib is connected with the corresponding sliding block through a tension lock net. Compared with the prior art, the umbrella-shaped unfolding and folding mechanism based on the shape memory alloy has the advantages that the stability of the unfolding state is high, and the energy conversion rate and the light weight of the device are remarkably improved.

Description

Technical Field

[0001] The present invention relates to the technical field of aerospace equipment, and in particular, to an umbrella-shaped deployment and retraction mechanism and a spacecraft based on shape memory alloy. Background Art

[0002] A spacecraft, also known as a space vehicle or a space flyer, refers to various flying vehicles that operate in space according to the laws of celestial mechanics and perform specific tasks such as exploring, developing, and utilizing space and celestial bodies. Currently, many spacecrafts have deployment and retraction mechanisms, such as spacecrafts like detection, meteorological, and communication satellites, as well as lunar rovers. The deployment and retraction mechanism of a spacecraft is in a folded and retracted state during the launch process and is fixedly placed in the payload compartment. After the launch is completed and the designated position is reached, the ground control center or the spacecraft itself can control the deployment and retraction mechanism to unfold as required, lock it after reaching the preset form, and operate normally.

[0003] Traditional antenna deployment schemes mainly rely on mechanical structure design and material selection to achieve the deployment, positioning, and retention of the antenna, and need to comprehensively consider factors such as the type, size, weight, performance requirements, and application scenarios of the antenna. Such products generally use a mechanical drive source composed of a motor and a transmission mechanism. Although they have advantages such as high stability and reliability, the mechanical drive source usually directly converts kinetic energy through mechanical elements to achieve driving, and its force application method is relatively single, which limits its adaptability in complex motion states; moreover, components such as motors and transmission mechanisms often have large weights and volumes, which is not conducive to the lightweight and miniaturization design of the antenna.

[0004] Therefore, with the continuous development of aerospace technology, the performance requirements for space antennas are also getting higher and higher, and the traditional mechanical antenna structure can no longer meet the needs of modern aerospace missions. Summary of the Invention

[0005] The present invention aims to solve at least one of the above technical problems.

[0006] The present invention provides an umbrella-shaped deployment and retraction mechanism based on shape memory alloy, including: a first tube body, a second tube body, a base, a tensioned lock net, a radiation rib, an SMA drive spring, a propulsion plate, a slider, and a power source;

[0007] The first tube body is sleeved on the second tube body, and there is a gap between the inner wall of the first tube body and the outer wall of the second tube body. The lower ends of the first tube body and the second tube body are respectively connected to the base;

[0008] The power source is arranged in the base and is electrically connected to the SMA drive spring, and the SMA drive spring is used to be heated and generate a high-temperature memory deformation;

[0009] A window communicating with the gap is formed in the second tube body. The push plate is hinged at the window. One end of the SMA driving spring is connected to the inner wall of the first tube body, and the other end is used to pass through the window and connect with the push plate. The slider is slidably connected to the inner wall of the second tube body. The SMA driving spring is used to drive the push plate to deflect when deforming, and the slider is used to slide along the length direction of the second tube body under the action of the extrusion force generated when the push plate deflects.

[0010] A plurality of the radiation ribs are arranged around the first tube body at intervals and one end of each radiation rib is hinged to the base. Each radiation rib and the slider are respectively connected by the tensioning wire mesh. The slider is used to drive a plurality of the radiation ribs to rotate relative to the base and perform unfolding or folding deformation through the plurality of tensioning wire meshes.

[0011] An umbrella-shaped unfolding and folding mechanism based on shape memory alloy provided by the present invention has the following beneficial effects compared with the prior art, but is not limited to:

[0012] The umbrella-shaped unfolding and folding mechanism based on shape memory alloy described in the present invention uses shape memory alloy (SMA driving spring 6) and mechanical structure to realize the unfolding and folding of the mechanism, has certain structural stiffness and stability, and can realize the unfolding and folding operation in orbit, adjust the unfolding diameter, angle and attitude, without replacing parts or external auxiliary operations. In the unfolded state of the device, the radiation ribs provide the tension force. Therefore, compared with the mechanism relying only on SMA material or SMPC (Shape Memory Polymer Composites) hinge, the tension force of the present invention is significantly increased, the stability in the unfolded state is greater, and it is not easily changed by external forces. Moreover, compared with the traditional mechanical unfolding mechanism, a lighter SMA driving spring is used as the driving source, and the energy conversion rate and the light weight of the device are significantly improved.

[0013] Optionally, a U-shaped groove is formed in the side wall of the slider towards the central position. The push plate passes through the U-shaped groove and abuts against the inner wall of the U-shaped groove.

[0014] Optionally, a through long slot hole is formed in the middle position of the radiation rib. After being subjected to the pulling force of the tensioning wire mesh, a plurality of the radiation ribs rotate and fold relative to the base, and elastically bend at the position of the long slot hole until folding is formed.

[0015] Optionally, a first through hole communicating with the gap is formed at one end of the first pipe body away from the base, and a second through hole communicating with the gap is formed at one end of the first pipe body close to the base. A third through hole communicating with the gap is formed at one end of the second pipe body away from the base. The tensioning wire mesh includes a first wire body and a second wire body. One end of the first wire body is connected to the radiation rib at a position close to the long slot hole, and the other end sequentially passes through the first through hole and the third through hole and is connected to the slider. One end of the second wire body is connected to one end of the radiation rib away from the base, and the other end sequentially passes through the second through hole and the third through hole and is connected to the slider.

[0016] Optionally, the tensioning wire mesh is used to be connected to the radiation rib through a fixing bolt. The fixing bolt includes a bottom plate, a locking plate, a buckle and a fixing rod. The bottom plate is connected to the radiation rib. Two locking plates are hinged to the bottom plate in parallel. Each locking plate is provided with the buckle. Tooth-shaped holes are respectively formed at one ends of the two locking plates close to each other. The tensioning wire mesh is used to pass through between the tooth-shaped holes of the two locking plates. Two fixing rods are arranged on the bottom plate at intervals. When the two locking plates respectively rotate relative to the bottom plate until the two tooth-shaped holes clamp the tensioning wire mesh, the buckles on the two locking plates are respectively clamped to the two fixing rods.

[0017] Optionally, the umbrella-shaped unfolding and folding mechanism based on shape memory alloy further includes a top seat, and the top seat is connected to one ends of the first pipe body and the second pipe body away from the base.

[0018] Optionally, a first annular groove and a second annular groove are formed on the top seat. One end of the first pipe body away from the base is embedded in the first annular groove, and one end of the second pipe body away from the base is embedded in the second annular groove.

[0019] Optionally, the umbrella-shaped unfolding and folding mechanism based on shape memory alloy further includes a controller. A groove is formed on the base, and both the power supply and the controller are arranged in the groove. The controller is used to control the switch of the power supply.

[0020] Optionally, a distance measuring sensor is arranged in the groove. The distance measuring sensor is in communication connection with the controller and is used to obtain the distance information between the slider and the base and feed back the distance information to the controller.

[0021] In addition, the present invention further provides a spacecraft, including the umbrella-shaped unfolding and folding mechanism based on shape memory alloy as described above.

[0022] Since the technical improvements and achieved technical effects of the spacecraft are the same as those of the umbrella-shaped deployment and retraction mechanism based on shape memory alloy, the technical effects of the spacecraft will not be described in detail herein. Brief Description of the Drawings

[0023] Figure 1 Schematic structural diagram of the umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to an embodiment of the present invention in a deployed state;

[0024] Figure 2 Schematic structural diagram of the umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to an embodiment of the present invention in a retracted state;

[0025] Figure 3 Cross-sectional view of the umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to an embodiment of the present invention;

[0026] Figure 4 For Figure 3 Partial enlarged view at A in

[0027] Figure 5 For Figure 3 Partial enlarged view at B in

[0028] Figure 6 Schematic structural diagram of the first tube body according to an embodiment of the present invention;

[0029] Figure 7 Schematic structural diagram of the second tube body according to an embodiment of the present invention;

[0030] Figure 8 For Figure 7 Partial enlarged view at C in

[0031] Figure 9 Cross-sectional view of the propulsion plate and the slider in the second tube body according to an embodiment of the present invention;

[0032] Figure 10 Top view of the slider according to an embodiment of the present invention;

[0033] Figure 11 Schematic structural diagram of the base according to an embodiment of the present invention;

[0034] Figure 12 Schematic structural diagram of the top seat according to an embodiment of the present invention;

[0035] Figure 13 Schematic structural diagram of the radiation ribs in a deployed state according to an embodiment of the present invention;

[0036] Figure 14 Schematic structural diagram of the radiation ribs in a retracted state according to an embodiment of the present invention;

[0037] Figure 15Stereogram of the fixing bolt according to an embodiment of the present invention;

[0038] Figure 16 Top view of the fixing bolt according to an embodiment of the present invention;

[0039] Figure 17 Schematic diagram of the tensile locking net driving the deformation of the radiation ribs according to an embodiment of the present invention.

[0040] Explanation of reference numerals:

[0041] The first pipe body 1, the first through hole 11, the second through hole 12, the second pipe body 2, the window 21, the third through hole 22, the pin shaft 23, the base 3, the groove 31, the tensile locking net 4, the first rope body 41, the second rope body 42, the radiation rib 5, the long slot hole 51, the SMA driving spring 6, the propulsion plate 7, the slider 8, the U-shaped groove 81, the fixing bolt 9, the bottom plate 91, the locking plate 92, the buckle 93, the fixing rod 94, the toothed hole 95, the top seat 10, the first annular groove 101, the second annular groove 102. Detailed implementation manners

[0042] To make the above objects, features and advantages of the present invention more obvious and understandable, the following detailed description of the specific embodiments of the present invention is provided in conjunction with the accompanying drawings.

[0043] In the description of the present invention, the orientation or positional relationship indicated by "upper", "lower", "left", "right", "top", "bottom", "front", "rear", "inner" and "outer" is based on the orientation or positional relationship shown in the accompanying drawings. It is only for the convenience of describing the present invention, rather than indicating or implying that the device referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on the protection scope of the present invention.

[0044] In the description of the present invention, it should be noted that, unless otherwise clearly defined and limited, the terms "set", "installed", "connected", "connected" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two components. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0045] In the description of this specification, the descriptions referring to terms such as "embodiment", "one embodiment", and "one implementation manner" mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or implementation manner are included in at least one embodiment or implementation manner of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or implementation manner. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or implementation manners.

[0046] Moreover, in the drawings, the Z-axis represents the vertical direction, that is, the up-and-down position, and the positive direction of the Z-axis (that is, the direction of the arrow of the Z-axis) represents up, and the negative direction of the Z-axis (that is, the direction opposite to the positive direction of the Z-axis) represents down.

[0047] It should be noted at the same time that the above meaning represented by the Z-axis is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0048] As Figures 1 to 11 shown, the umbrella-shaped unfolding and folding mechanism based on shape memory alloy according to the embodiment of the present invention includes: a first tube body 1, a second tube body 2, a base 3, a tensioning lock net 4, a radiation rib 5, an SMA driving spring 6, a push plate 7, a slider 8, and a power source;

[0049] The first tube body 1 is sleeved on the second tube body 2, and there is a gap between the inner wall of the first tube body 1 and the outer wall of the second tube body 2. The lower ends of the first tube body 1 and the second tube body 2 are respectively connected to the base 3;

[0050] The power source is arranged in the base 3 and is electrically connected to the SMA driving spring 6. The SMA driving spring 6 is used to be heated and generate a high-temperature memory deformation;

[0051] A window 21 communicating with the gap is opened on the second tube body 2. The push plate 7 is hinged at the window 21. One end of the SMA driving spring 6 is connected to the inner wall of the first tube body 1, and the other end is used to pass through the window 21 and be connected to the push plate 7. The slider 8 is slidably connected to the inner wall of the second tube body 2. The SMA driving spring 6 is used to drive the push plate 7 to deflect when deforming, and the slider 8 is used to slide along the length direction of the second tube body 2 under the action of the extrusion force generated when the push plate 7 deflects;

[0052] A plurality of the radiation ribs 5 are arranged at intervals around the first tube body 1 and one end of each radiation rib 5 is hinged to the base 3. Each radiation rib 5 is respectively connected to the slider 8 through the tension lock net 4. The slider 8 is used to drive the plurality of radiation ribs 5 to rotate relative to the base 3 through the plurality of tension lock nets 4 and perform expansion or contraction deformation.

[0053] Specifically, as shown in the attached Figures 7 to 9 figures, the window 21 may include two long slots symmetrically opened on the second tube body 2, so that the push plate 7 can pass through the two long slots to deflect to a large extent; the upper end of the push plate 7 can be hinged to the upper position of one of the windows 21 through a pin shaft 23, and one end of the SMA driving spring 6 (as shown in the attached Figure 4 figures) can pass through the other window 21 and be connected to the lower end of the push plate 7. In this way, the driving force arm of the push plate 7 can be longer, and then a smaller driving force generated when the SMA driving spring 6 expands and contracts can drive the push plate 7 to deflect.

[0054] The SMA driving spring 6 is quenched and restored to room temperature after being compressed at high temperature. The initial memory form is a compression spring, and the high-temperature memory form is a stretched spring. The SMA driving spring 6 is made of shape memory alloys (SMA), such as nickel-titanium (NiTi) shape memory alloy.

[0055] In this embodiment, as shown in the attached Figure 1 to the attached Figure 11 figures, when the umbrella-shaped unfolding and folding mechanism based on shape memory alloy switches from the unfolded state to the folded state, first, the power is turned on, and the SMA driving spring 6 starts to heat up. The SMA driving spring 6 gradually changes into a stretched spring in the high-temperature memory form, thereby gradually driving the push plate 7 to deflect. And during the rotation of the push plate 7, it will squeeze the slider 8. The pressure can be decomposed into vertical and horizontal pressures. The vertical pressure (in the Z-axis direction in the attached Figure 1 figures) makes the slider 8 move downward. At the same time, the tension lock net 4 fixedly connected to the upper end of the slider 8 moves downward with the slider 8, pulling the radiation rib 5 to rotate relative to the base 3 towards the direction close to the first tube body 1. When the SMA driving spring 6 extends to the maximum stroke, the radiation rib 5 is approximately parallel to and attached to the first tube body 1, showing a folded state. At this time, the power is still kept on, so that the SMA driving spring 6 remains in the extended state. During this process, the supporting force transmitted to the slider 8 through the push plate 7 is always greater than the restoring force generated by the radiation rib 5 to restore the extended state of the tension lock net 4 connected to the upper end of the slider 8, so that the slider 8 is fixed at the current position, and the overall mechanism is in a stable folded state (as shown in the attached Figure 2as shown); when the umbrella-shaped deployment and retraction mechanism based on shape memory alloy switches from the retracted state to the deployed state, first, the power supply is turned off, and the heating of the SMA driving spring 6 is stopped. The SMA driving spring 6 gradually becomes a compression spring in its initial memory form, thereby driving the push plate 7 to gradually deflect in the opposite direction to reduce and then release the supporting force on the slider 8. At this time, the elastic restoring force of the elastic member provided between the radiation ribs 5 and the base 3 or the restoring force generated by the bending deformation of the radiation ribs 5 themselves (for example, the restoring force generated by the bending deformation of the radiation ribs 5 at the long slot hole 51 described later) can be used to drive the radiation ribs 5 to return to the deployed state. At this time, the elastic restoring force will be transmitted to the slider 8 along the tensioned lock net 4, thereby gradually driving the slider 8 to move upward. And during this process, the tension force of the radiation ribs 5 on the tensioned lock net 4 is greater than the supporting force provided by the push plate 7 to the slider 8 throughout the deployment process. Therefore, the slider 8 can move upward slowly. During this process, the tension force provided by the radiation ribs 5 continuously decreases. After being fully deployed, the slider 8 stably maintains the current state, and the overall mechanism is in a stable deployed state (attached Figure 1 as shown). The umbrella-shaped deployment and retraction mechanism based on shape memory alloy of the present invention, compared with the prior art, uses shape memory alloy (SMA driving spring 6) and mechanical structure to realize the deployment and retraction of the mechanism, has certain structural stiffness and stability, and can realize the deployment and retraction operation in orbit, adjust the deployment diameter, angle, and attitude, without replacing parts or external auxiliary operations. Since the device provides the tension force by elastic force in the deployed state, compared with the mechanism relying only on SMA material or SMPC (Shape Memory Polymer Composites) hinge, the present invention has a significantly increased tension force, greater stability in the deployed state, and is not easily changed by external forces. Moreover, compared with the traditional mechanical deployment mechanism, a lighter SMA driving spring is used as the driving source, and the energy conversion rate and the light weight of the device are significantly improved.

[0056] Optionally, a U-shaped groove 81 is formed in the side wall of the slider 8 towards the central position. The push plate 7 passes through the U-shaped groove 81 and abuts against the inner wall of the U-shaped groove 81.

[0057] In this embodiment, in combination with attached Figure 5 and attached Figure 10 as shown, the slider 8 is a cylindrical structure with a notch, and this notch is a U-shaped groove 81 formed in the side wall of the slider 8 towards the central position. In combination with attached Figure 9 as shown, the push plate 7 can pass through the U-shaped groove 81 and abut against the inner wall of the U-shaped groove 81. The U-shaped groove 81 can provide limit and rotation guidance for the push plate 7. When the umbrella-shaped deployment and retraction mechanism based on shape memory alloy switches from the deployed state to the retracted state, the SMA driving spring 6 drives the push plate 7 to deflect, and the push plate 7 will squeeze the slider 8 during the rotation process, causing the slider 8 to move downward (attachedFigure 1 It moves in the opposite direction of the Z-axis. Conversely, when the umbrella-shaped unfolding and folding mechanism based on shape memory alloy switches from the folded state to the unfolded state, the SMA driving spring 6 drives the pushing plate 7 to deflect in the opposite direction. The radiation ribs 5 provide a tension force due to the recovery of their own bending deformation, and transmit the tension force along the tension locking net 4 to the slider 8, thereby gradually driving the slider 8 to move upward.

[0058] Optionally, a through long slot hole 51 is provided at the middle position of the radiation rib 5. After the plurality of radiation ribs 5 are subjected to the pulling force of the tension locking net 4, they rotate and fold relative to the base 3, and elastically bend at the position of the long slot hole 51 until folding is formed.

[0059] In this embodiment, in combination with the attached Figure 13 and the attached Figure 14 As shown, the radiation rib 5 can be made of carbon fiber material, and the radiation rib 5 has the characteristic of restoring its original shape after deformation. A through long slot hole 51 is provided at the middle position of the radiation rib 5. After the radiation rib 5 is subjected to the pulling force of the tension locking net 4, it can not only fold relative to the first pipe body 1, but also elastically bend at the position of the long slot hole 51 to achieve folding (as shown in the attached Figure 2 and the attached Figure 14 As shown), thereby further reducing the length of the radiation rib 5 after folding. Moreover, the radiation rib 5 is in an elastic deformation state in the folded state. Furthermore, when the device switches from the folded state to the unfolded state, the tension force in the unfolded state can be provided by the elastic restoring force of the radiation rib itself. Therefore, compared with the mechanism relying only on SMA material or SMPC (Shape Memory Polymer Composites) hinge, the tension force of the present invention is significantly increased, the stability in the unfolded state is greater, and it is not easily changed by external forces.

[0060] Optionally, a first through hole 11 communicating with the gap is provided at one end of the first pipe body 1 away from the base 3, a second through hole 12 communicating with the gap is provided at one end close to the base 3, a third through hole 22 communicating with the gap is provided at one end of the second pipe body 2 away from the base 3. The tension locking net 4 includes a first rope body 41 and a second rope body 42. One end of the first rope body 41 is connected to the position of the radiation rib 5 close to the long slot hole 51, and the other end sequentially passes through the first through hole 11 and the third through hole 22 and is connected to the slider 8. One end of the second rope body 42 is connected to the end of the radiation rib 5 away from the base 3, and the other end sequentially passes through the second through hole 12 and the third through hole 22 and is connected to the slider 8.

[0061] In this embodiment, in combination with the attached Figure 6 and the attached Figure 7As shown, at the upper end of the first tube body 1 (in the positive Z-axis direction in the figure), a plurality of first through holes 11 are provided, and at the lower end, a plurality of second through holes 12 are provided. At the upper end of the second tube body 2, a plurality of third through holes 22 are provided. Combining the figure shown, one end of the first rope body 41 is connected to the radiation rib 5 at a position close to the long slot hole 51, and the other end sequentially passes through the first through hole 11 and the third through hole 22 and is connected to the upper end of the slider 8. One end of the second rope body 42 is connected to the end of the radiation rib 5 far from the base 3, and the other end sequentially passes through the second through hole 12 and the third through hole 22 and is connected to the slider 8. That is, the second rope body 42 first passes through the second through hole 12, then goes up along the gap between the first tube body 1 and the second tube body 2, and finally passes through the second through hole 12 and extends into the interior of the second tube body 2, and is finally connected to the upper end of the slider 8. Combining the figure shown, when the slider 8 moves downward, the first rope body 41 and the second rope body 42 will be bent in the direction indicated by the arrow in the figure until they become the state shown in the figure or the figure. Figure 6 In the positive Z-axis direction in the figure, a plurality of first through holes 11 are provided at the upper end of the first tube body 1, and a plurality of second through holes 12 are provided at the lower end. At the upper end of the second tube body 2, a plurality of third through holes 22 are provided. Figure 17 As shown in the figure, one end of the first rope body 41 is connected to the radiation rib 5 at a position close to the long slot hole 51, and the other end sequentially passes through the first through hole 11 and the third through hole 22 and is connected to the upper end of the slider 8. One end of the second rope body 42 is connected to the end of the radiation rib 5 far from the base 3, and the other end sequentially passes through the second through hole 12 and the third through hole 22 and is connected to the slider 8. That is, the second rope body 42 first passes through the second through hole 12, then goes up along the gap between the first tube body 1 and the second tube body 2, and finally passes through the second through hole 12 and extends into the interior of the second tube body 2, and is finally connected to the upper end of the slider 8. Figure 17 As shown in the figure, when the slider 8 moves downward, the first rope body 41 and the second rope body 42 will Figure 17 be bent in the direction indicated by the arrow in the figure until they become Figure 2 or Figure 14 the state shown in the figure.

[0062] Optionally, the tensioning lock net 4 is used to be connected to the radiation rib 5 through the fixing bolt 9. The fixing bolt 9 includes a bottom plate 91, a locking plate 92, a buckle 93 and a fixing rod 94. The bottom plate 91 is connected to the radiation rib 5. Two locking plates 92 are juxtaposed and hinged to the bottom plate 91. Each locking plate 92 is respectively provided with the buckle 93. At the ends of the two locking plates 92 close to each other, tooth-shaped holes 95 are respectively provided. The tensioning lock net 4 is used to pass through between the tooth-shaped holes 95 of the two locking plates 92. Two fixing rods 94 are arranged on the bottom plate 91 at intervals. When the two locking plates 92 are respectively rotated relative to the bottom plate 91 until the two tooth-shaped holes 95 clamp the tensioning lock net 4, the buckles 93 on the two locking plates 92 are respectively clamped to the two fixing rods 94.

[0063] In this embodiment, combining the figure shown, Figure 13 the tensioning lock net 4 (the first rope body 41 and the second rope body 42) can be connected to the radiation rib 5 through the fixing bolt 9. Combining the figure shown, Figure 15 and Figure 16As shown, the fixing bolt 9 includes a bottom plate 91, a locking plate 92, a buckle 93 and a fixing rod 94. When not locked, the two locking plates 92 can rotate flexibly relative to the bottom plate 91. When locking is required, the tensioning lock net 4 is passed through between the toothed holes 95 of the two locking plates 92. By pulling the tensioning lock net 4, the locking plates 92 are driven to rotate. When the locking plates 92 turn to the horizontal position, since the buckle 93 above the locking plates 92 is stuck into the fixing rod 94, the rotation of the locking plates 92 is restricted by the buckle 93 at this time. The two locking plates 92 are kept parallel. The teeth of the toothed holes 95 of the two locking plates 92 are inserted into the tensioning lock net 4 to clamp the tensioning lock net 4. At this time, the fixing bolt 9 and the tensioning lock net 4 are locked. The fixing bolt 9 is fixed to the radiation rib 5 by screws or riveting, and the fixation of the tensioning lock net 4 and the radiation rib 5 can be realized. The fixing bolt 9 adopts a unique mousetrap-like design, making it have good reliability and can be unlocked, which is convenient for disassembly and maintenance and replacement of the tensioning lock net 4.

[0064] Optionally, the umbrella-shaped unfolding and folding mechanism based on shape memory alloy further includes a top seat 10, and the top seat 10 is connected to one ends of the first tube 1 and the second tube 2 far away from the base 3.

[0065] In this embodiment, in combination with the attached Figures 1 to 3 As shown, at the upper ends of the first tube 1 and the second tube 2 (in the positive Z-axis direction in the attached Figure 1 or the attached Figure 3 ), a top seat 10 is connected. The top seat 10 acts similar to an end cap and plays a role in protecting the first tube 1 and the second tube 2.

[0066] Optionally, the top seat 10 is provided with a first annular groove 101 and a second annular groove 102. One end of the first tube 1 far away from the base 3 is embedded in the first annular groove 101, and one end of the second tube 2 far away from the base 3 is embedded in the second annular groove 102.

[0067] In this embodiment, in combination with the attached Figure 12 As shown, the top seat 10 is provided with a first annular groove 101 and a second annular groove 102. The upper end of the first tube 1 (in the positive Z-axis direction in the attached Figure 1 or the attached Figure 3 ) can be embedded in the first annular groove 101, and the upper end of the second tube 2 can be embedded in the second annular groove 102. In this way, the first tube 1 and the second tube 2 can be kept coaxial.

[0068] Optionally, the umbrella-shaped unfolding and folding mechanism based on shape memory alloy further includes a controller. A groove 31 is provided on the base 3, and both the power supply and the controller are arranged in the groove 31. The controller is used to control the switch of the power supply.

[0069] In this embodiment, in combination with the attachedFigure 11 As shown, a plurality of pin shafts for hinging with the radiation ribs 5 are arranged at intervals on the outer periphery of the base 3, and a groove 31 is formed in the middle position thereof. The power supply and the controller are both arranged in the groove 31. The power supply is directly connected to the controller and the controller controls the switch of the power supply. Based on controlling the power supply state, by utilizing the characteristic that the shape memory alloy (SMA driving spring 6) changes its shape under the influence of temperature, the task of repeated unfolding and folding of the mechanism in the use environment, that is, during the operation of the spacecraft, is realized.

[0070] In other embodiments, the controller can be added with an intelligent control computer and a voltage output control device. The measurement data is fed back to the intelligent control computer, and the intelligent control computer adjusts the supply voltage of the power supply to the SMA driving spring 6 by analyzing the data to calculate the unfolding and folding conditions of the mechanism, so as to finely adjust the restoration form of the SMA driving spring 6 to ensure the stability during the unfolding or folding process. At the same time, the intelligent control computer judges the real-time unfolding work progress or folding work progress through the analysis of the data.

[0071] Optionally, a ranging sensor is arranged in the groove 31. The ranging sensor is communicatively connected with the controller and is used for obtaining the distance information between the slider 8 and the base 3 and feeding back the distance information to the controller.

[0072] In this embodiment, the groove 31 is communicated with the inside of the second tube body 2. The ranging sensor in the groove 31 can obtain the distance information between the slider 8 and the base 3 and feed back the distance information to the controller. The deformation characteristics of the SMA driving spring 6 can be judged through the distance change, so as to calculate the unfolding and folding conditions of the mechanism, thereby serving as a feedback device for unfolding and folding.

[0073] In addition, the present invention also provides a spacecraft, including the umbrella-shaped unfolding and folding mechanism based on shape memory alloy as described above.

[0074] Since the technical improvement and the obtained technical effects of the spacecraft are the same as those of the umbrella-shaped unfolding and folding mechanism based on shape memory alloy, the technical effects of the spacecraft will not be described in detail herein.

[0075] The terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one such feature.

[0076] Although the present invention is disclosed as above, the protection scope of the present invention is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, and these changes and modifications will all fall within the protection scope of the present invention.

Claims

1. An umbrella-shaped deployment and retraction mechanism based on shape memory alloy, characterized in that: include: A first tube body (1), a second tube body (2), a base (3), a tension lock net (4), a radiation rib (5), an SMA drive spring (6), a propulsion plate (7), a slider (8) and a power source; The first tube body (1) is sleeved on the second tube body (2), and a gap is left between the inner wall of the first tube body (1) and the outer wall of the second tube body (2), and the lower ends of the first tube body (1) and the second tube body (2) are respectively connected to the base (3); The power source is arranged in the base (3) and is electrically connected to the SMA drive spring (6), and the SMA drive spring (6) is used to be heated and generate high-temperature memory deformation; The second tube body (2) is provided with a window (21) which is in communication with the gap; the push plate (7) is hinged at the window (21); one end of the SMA drive spring (6) is connected to the inner wall of the first tube body (1); the other end is used to pass through the window (21) and be connected to the push plate (7); the slider (8) is slidably connected to the inner wall of the second tube body (2); the SMA drive spring (6) is used to drive the push plate (7) to deflect when deformation occurs; and the slider (8) is used to slide along the length direction of the second tube body (2) under the action of the extrusion force generated when the push plate (7) deflects; A plurality of the radiation ribs (5) are arranged at intervals around the first tube body (1) and one end of the radiation ribs (5) is hinged to the base (3); each of the radiation ribs (5) is connected to the slider (8) via the tensioning and locking net (4); the slider (8) is used to drive the plurality of radiation ribs (5) to rotate relative to the base (3) and to expand or retract the deformation via the plurality of tensioning and locking nets (4).

2. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 1, characterized in that: The sliding block (8) is provided with a U-shaped groove (81) along its side wall toward the center, and the pushing plate (7) passes through the U-shaped groove (81) and abuts against the inner wall of the U-shaped groove (81).

3. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 1, characterized in that: A through long slot hole (51) is provided in the middle of the radiation rib (5). After being pulled by the tensioning net (4), the radiation ribs (5) rotate and gather relative to the base (3) and are elastically bent at the position of the long slot hole (51) until they are folded.

4. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 3 is characterized in that: The first tube body (1) is provided with a first through hole (11) communicating with the gap at one end away from the base (3), and a second through hole (12) communicating with the gap at one end close to the base (3); the second tube body (2) is provided with a third through hole (22) communicating with the gap at one end away from the base (3); the tension lock net (4) comprises a first rope body (41) and a second rope body (42); one end of the first rope body (41) is connected to a position of the radiation rib (5) close to the long slot hole (51), and the other end passes through the first through hole (11) and the third through hole (22) in sequence and is connected to the slider (8); one end of the second rope body (42) is connected to an end of the radiation rib (5) away from the base (3), and the other end passes through the second through hole (12) and the third through hole (22) in sequence and is connected to the slider (8).

5. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 1, characterized in that: The tension lock net (4) is used to be connected to the radiation rib (5) through a fixing bolt (9), the fixing bolt (9) comprising a bottom plate (91), a locking plate (92), a buckle (93) and a fixing rod (94), the bottom plate (91) is connected to the radiation rib (5), two locking plates (92) are hinged to the bottom plate (91) in parallel, each locking plate (92) is provided with the buckle (93), and the two locking plates (92) are respectively connected to each other at one end thereof. A tooth-shaped hole (95) is separately provided, and the tension lock net (4) is used to pass through the tooth-shaped holes (95) of the two locking plates (92); two fixing rods (94) are arranged on the bottom plate (91) at intervals, and when the two locking plates (92) are respectively rotated relative to the bottom plate (91) until the two tooth-shaped holes (95) clamp the tension lock net (4), the buckles (93) on the two locking plates (92) are respectively clamped on the two fixing rods (94).

6. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 1, characterized in that: It also comprises a top seat (10), wherein the top seat (10) is connected to one end of the first tube body (1) and the second tube body (2) away from the base (3).

7. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 6, characterized in that: The top seat (10) is provided with a first annular groove (101) and a second annular groove (102); an end of the first tube body (1) away from the base (3) is embedded in the first annular groove (101), and an end of the second tube body (2) away from the base (3) is embedded in the second annular groove (102).

8. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 1, characterized in that: It also comprises a controller. A groove (31) is provided on the base (3). The power supply and the controller are both arranged in the groove (31). The controller is used to control the switch of the power supply.

9. The umbrella-shaped deployment and retraction mechanism based on shape memory alloy according to claim 8, characterized in that: A distance measuring sensor is arranged in the groove (31), and the distance measuring sensor is communicatively connected with the controller, and is used to obtain distance information between the slider (8) and the base (3), and feed the distance information back to the controller.

10. A spacecraft, characterized in that: It comprises the umbrella-shaped deployment and retraction mechanism based on shape memory alloy as described in any one of claims 1 to 9.

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