Three-dimensional resistance-increasing derail sail

Abstract

The invention discloses a three-dimensional resistance-increasing deorbit sail, which relates to the technical field of spacecraft deorbit and comprises a base and at least two supporting retracting and releasing mechanisms, a sail storage device is arranged between every two adjacent supporting folding and unfolding mechanisms. The supporting retracting and releasing mechanisms are distributed in the circumferential direction around the axis of the base. The supporting and retracting mechanisms are provided with telescopic ruler belts, the free ends of the ruler belts are connected with one corner of the triangular canvas stored in the canvas storage device, and the ruler belts of the supporting and retracting mechanisms on the two adjacent sides of the triangular canvas drive the supporting and retracting mechanisms to achieve retracting and retracting actions. The device is simple in structure, convenient for repeated experiments on the ground, low in cost, provided with a self-stabilization structure, capable of increasing resistance in multiple directions and capable of achieving high synchronism and reliability of the sail surface.

Description

Technical Field

[0001] The present invention relates to the technical field of spacecraft deorbiting, and in particular to a three-dimensional drag-enhancing deorbiting sail. Background Art

[0002] With the development of aerospace technology, the number of space debris is increasing day by day. The orbit with the most dense distribution of space debris is the low Earth orbit, and its natural orbit descent time is extremely slow, which will pose a safety threat to spacecraft working normally in this area, and is not conducive to the environmental stability and sustainable development of the low orbit. Therefore, in order to speed up the orbit descent time of spacecraft after they fail and become space debris, it is necessary to equip them with corresponding deorbit devices. In low Earth orbit, atmospheric drag perturbation is the most important perturbation force on spacecraft. The use of deorbit sails can effectively increase the surface-to-mass ratio of spacecraft and achieve rapid deorbit.

[0003] At present, the deorbiting methods of space debris are divided into dragging deorbiting, electrodynamic rope deorbiting, deorbiting sail deorbiting, chemical propulsion deorbiting, solar sail deorbiting and other methods. Among them, the deorbiting sail increases the friction resistance between the deorbiting target and the earth's upper atmosphere by greatly increasing the surface area of ​​the deorbiting target in its orbit. This resistance will accelerate the orbital decay of the target, and eventually cause the target to descend and be destroyed in the atmosphere. At present, the sail surface of the deorbiting sail is mostly flat, but the drag efficiency of the flat deorbiting sail is low, and it is very easy to have the risk of attitude instability when used in orbit. Based on this, an electrically driven three-dimensional drag-increasing deorbiting sail is provided to achieve low-cost, multi-directional drag increase and ensure that it has higher stability. Summary of the invention

[0004] The purpose of the present invention is to provide a three-dimensional drag-increasing off-orbit sail to solve the problems existing in the above-mentioned prior art, facilitate repeated experiments on the ground, have low cost, have a self-stabilizing configuration, can increase drag in multiple directions, and can achieve higher synchronization and reliability of the sail surface.

[0005] To achieve the above object, the present invention provides the following solutions:

[0006] The present invention provides a three-dimensional drag-enhancing off-track sail, comprising a base and at least two supporting and retracting mechanisms; a sail storage device is arranged between two adjacent supporting and retracting mechanisms; each of the supporting and retracting mechanisms and the sail storage device is fixedly arranged on the base, and each of the supporting and retracting mechanisms is circumferentially distributed around the axis of the base; the supporting and retracting mechanism comprises a retracting bracket, a storage device, a tape ruler, an active friction shaft, a driven friction shaft and a driving motor; the retracting bracket is fixedly arranged on the base; the storage device is arranged on the retracting bracket; one end of the tape ruler can be wound and stored in the storage device, and the free end of the tape ruler can be extended and retracted along an inclined direction toward the axis direction away from the base, and the inclined direction has an angle with the axis of the base; the active friction shaft and The driven friction shaft is arranged opposite to each other, and the active friction shaft and the driven friction shaft are both rotatably arranged on the retractable bracket; the ruler tape is passed through the gap between the active friction shaft and the driven friction shaft; the drive motor is arranged on the retractable bracket, and the output shaft of the drive motor is used to drive the active friction shaft to rotate; the sail storage device has a storage cavity and an opening connected to the storage cavity; a triangular canvas is placed in the storage cavity; the triangular canvas has a first corner point, a second corner point and a third corner point; the first corner point is used to be fixed on the sail storage device, the second corner point is connected to the free end of the ruler tape of the adjacent support and retractable mechanism, and the third corner point is connected to the free end of the ruler tape of another adjacent support and retractable mechanism.

[0007] Preferably, the supporting and retracting mechanism also includes a clamp; the clamp is arranged on the retracting bracket, and the driven friction shaft is rotatably arranged on the clamp; the clamp can drive the driven friction shaft to maintain a tendency to approach the active friction shaft.

[0008] Preferably, the clamping device includes two swinging components; the two swinging components are symmetrically arranged on the retractable bracket; the swinging component includes a swinging plate and a compression spring; the swinging plate is rotatably arranged on the retractable bracket around a first axis; the swinging plate is provided with a pushing portion, and a accommodating groove is provided at a position corresponding to the pushing portion on the retractable bracket, the compression spring is arranged in the accommodating groove, and one end of the compression spring abuts against the pushing portion; the two ends of the driven friction shaft are respectively connected to the corresponding swinging plates for rotation around a second axis, and the second axis is parallel to the first axis; after the compression spring is able to push the pushing portion, the swinging plate can drive the driven friction shaft to move around the first axis to the side close to the active friction shaft.

[0009] Preferably, the supporting and retracting mechanism also includes a lateral limiting mechanism; the lateral limiting mechanism includes two lateral limiting wheels; the two lateral limiting wheels are both located on the side of the active friction shaft close to the free end of the ruler tape; each of the lateral limiting wheels is rotatably arranged on the retracting bracket; the two lateral limiting wheels are respectively located on both sides below the ruler tape; and each of the lateral limiting wheels is in rolling contact with the ruler tape at the position where it contacts the ruler tape.

[0010] Preferably, the number of the supporting and retracting mechanisms is 4; and the supporting and retracting mechanisms are evenly distributed circumferentially around the axis of the base.

[0011] Preferably, the triangular canvas is folded and placed in the storage cavity; the triangular canvas is folded in an equidistant Z shape along a fold line parallel to the bottom edge of the triangular canvas to form a long strip; the long strip is folded in an unequal Z shape from the middle to both sides to form a final folded shape.

[0012] Preferably, the second corner point and the third corner point of the triangular canvas are connected to the corresponding free end of the ruler tape via a tension spring.

[0013] Preferably, the base includes a bottom plate and a plurality of bracket plates; each of the bracket plates is evenly fixed to the bottom plate in a circumferential direction around the axis of the bottom plate; and each of the supporting and retracting mechanisms is fixedly disposed on one of the bracket plates.

[0014] Preferably, it also includes a controller, which is communicatively connected with the driving motor of each supporting and retracting mechanism; the controller is fixedly arranged on the bottom plate within the enclosed space of each bracket plate.

[0015] Preferably, the sail storage device includes a storage box and a bottom bracket; the storage box is fixedly arranged at the upper end of the bottom bracket; the lower end of the bottom bracket is fixedly connected to the base; the storage box has the storage cavity and the opening; the opening faces the side away from the axis of the base; a through hole connected to the storage cavity is arranged above the storage box; the first corner point of the triangular canvas is fixedly connected to the outer wall of the storage box after passing through the through hole from the storage cavity.

[0016] Compared with the prior art, the present invention has achieved the following technical effects:

[0017] The three-dimensional drag-increasing off-orbit sail provided by the present invention is extended and retracted in the direction away from the axis of the base along the inclined direction by means of a ruler tape. When a plurality of circumferentially distributed supporting and retracting mechanisms work in coordination, when the sail surface is unfolded, these inclined ruler tapes pull the triangular canvases from different angles to form a pyramid shape as a whole. When the atmospheric flow hits the sail surface, the pyramid-shaped three-dimensional sail surface can not only realize multi-directional drag increase, but also provide a larger offset between the pressure center and the center of mass, and can provide a larger restoring torque when facing disturbances. In this way, the whole device will have a stronger anti-interference ability, that is, better attitude stability. Each supporting and retracting mechanism is driven by an independent motor. The machine drives the active friction shaft. In terms of control algorithm, the same speed and torque parameters can be set for each motor. Real-time monitoring and adjustment can be performed through encoders and other feedback elements to ensure that all tapes are extended and retracted synchronously, so that the various parts of the sail can be coordinated to unfold and fold to maintain good synchronization. The transmission of the support and retraction mechanism is achieved by the active friction shaft, the driven friction shaft and the drive motor. Compared with the release device of pyrotechnics, it is purely electrically driven and has the advantages of being safe, reusable, not affecting other components, and being able to change speed continuously. Compared with the release device based on memory alloy, it has the advantages of low cost and convenience for repeated experiments on the ground.

[0018] Furthermore, in the transmission mode in which the tape is inserted into the gap between the active friction shaft and the driven friction shaft, the clamping device allows the driven friction shaft to continuously approach the active friction shaft, and can always maintain the appropriate and stable clamping force of the two on the tape. This makes the friction force fluctuate very little during the friction transmission process, effectively avoiding the slipping of the tape due to insufficient friction, ensuring that the power output by the drive motor is stably and accurately transmitted to the tape, so that the tape retraction and extension action is continuous and smooth, which is very critical for the precise control of the deployment and folding of the sail surface. Since the three-dimensional drag-enhanced off-orbit sail is a multi-group support and folding mechanism working in coordination, the tape retraction and extension of all mechanisms must be highly synchronized to achieve a smooth and coordinated deployment and folding of the sail surface. The clamping device ensures the stability of the friction transmission in each support and folding mechanism, so that the speed and stroke of each group of tapes in response to the drive motor command are consistent, thereby strengthening the synchronization of the deployment and folding action of the entire sail surface, avoiding uneven force on the sail surface, stretching deformation, or even tearing due to the lag or advance of individual tapes.

[0019] Furthermore, the compression springs on both sides each provide a driving force for the corresponding swinging plate and work together. Under the conditions of long-term operation, temperature changes, slight wear of components, etc., even if there is a slight fluctuation in the elastic force of the spring on one side, the spring on the other side can assist in compensation, and still ensure that the driven friction shaft applies a relatively balanced clamping force to the scale tape, which is of great significance for maintaining a stable friction transmission and ensuring the accuracy of the sail surface movement. After repeated use, the friction shaft and the scale tape surface will inevitably produce a certain degree of wear, resulting in changes in the originally appropriate gap between the two. At this time, the compression spring can adapt to this wear condition by virtue of its own elasticity. As the gap increases, the spring pushes the swinging plate to rotate around the first axis, driving the driven friction shaft to approach the active friction shaft, automatically making up the gap, and maintaining a stable clamping force. There is no need for frequent manual intervention and adjustment, thereby ensuring the long-term stable operation of the device.

[0020] Furthermore, the two lateral limit wheels are respectively located on both sides below the ruler tape and in rolling contact with it, defining a precise path for the extension and retraction movement of the ruler tape. During the retraction and extension process, the ruler tape can only move along the direction specified by the lateral limit wheels to avoid lateral deviation to the left or right, which is crucial for the off-orbit sail, because the accuracy of the unfolding and folding of the sail surface directly depends on whether the ruler tape movement of each supporting and retracting mechanism is accurate. Precise guidance can prevent deformation and asymmetry of the sail surface due to deviation of the ruler tape, and ensure that the sail surface is unfolded and folded as expected by the design; the lateral limit wheels and the ruler tape adopt a rolling contact method. Compared with sliding friction, the rolling friction coefficient is extremely small. This rolling contact greatly reduces the friction between the two, reduces the risk of wear, fluffing and even breakage due to friction, and extends the service life.

[0021] Furthermore, the optimal configuration is to form a quadrangular pyramid structure after unfolding. The impact force of the airflow is evenly dispersed to the entire sail surface, and the tension in each area is relatively balanced, avoiding local stress concentration. This not only prevents the sail surface from tearing due to uneven force and extends the service life of the sail surface, but also maintains the stable three-dimensional configuration of the sail surface, ensuring the stability and sustainability of its drag-enhancing effect.

[0022] Furthermore, it adopts the Frog-leg folding method, which provides an orderly process for the unfolding of the canvas. Combined with the pulling of the tape supporting the retracting and releasing mechanism, it can accurately and smoothly restore the original triangular shape of the sail, reduce the jamming and entanglement that may occur due to sudden large-scale unfolding, and ensure the reliability and synchronization of the sail unfolding; the unequally spaced Z-shaped folding makes the final shape of the canvas more flexible and changeable, which can better fit the irregular contour of the storage cavity and make full use of the corner space inside the cavity. In actual engineering design, this reduces the strict requirements on the accuracy of the shape of the storage cavity, which is conducive to simplifying the mechanical design and manufacturing process of the device and indirectly controlling costs.

[0023] Furthermore, the tension spring connection can act as a buffer component. When encountering an instantaneous impact force, the tension spring can stretch quickly, absorb and store part of the energy, and avoid the impact force being directly and rigidly transmitted to the connection between the canvas and the tape, preventing this place from being damaged due to sudden strong impact, ensuring the structural integrity, and maintaining the normal function of the off-orbit sail; in actual operation, since the performance of the drive motors and the friction conditions of the transmission components of each supporting and retracting mechanism are difficult to be completely consistent, the tension applied by different tapes to the corners of the canvas may be slightly different. The tension spring can adapt to this uneven tension. When the tension of the tape on one side is slightly larger, the corresponding tension spring will stretch appropriately, otherwise it will retract and automatically adjust to make the force on the two corners of the canvas as balanced as possible, ensuring the smooth deployment of the sail, maintaining a stable three-dimensional configuration, and improving the stability of the drag-increasing effect; compared with the rigid connection, the tension spring gives the connection link a certain flexibility. In the early stage of the sail deployment, the tension spring is first stretched to drive the corners of the canvas to move in a more moderate manner, giving the entire sail a buffered start-up process to avoid the canvas from being torn or stuck at the fold due to excessive initial tension.

[0024] Furthermore, multiple bracket plates are evenly distributed around the axis of the bottom plate, so that the tension and stress carried by each support and retracting mechanism can be evenly dispersed on the bottom plate. When the deorbit sail is deployed, the sail surface is subjected to airflow resistance, and the corresponding support and retracting mechanism is pulled. The tension is dispersed and transmitted through the bracket plate to avoid stress concentration in one place, which can effectively prevent the base from deformation and damage, provide a solid and reliable support foundation for the entire device, and ensure the long-term stable operation of the deorbit sail.

[0025] Furthermore, the controller is connected to each drive motor in communication, just like building a "central command center" for the entire three-dimensional drag-enhancing deorbit sail. It can centrally send instructions, accurately set the speed, direction, start and stop time of each drive motor, and allow the scales of each supporting and retracting mechanism to be retracted and released synchronously, thereby ensuring that the unfolding and folding movements of the sail are uniform; fixing the controller on the bottom plate in the space enclosed by the bracket plate cleverly utilizes the originally idle space inside the base, avoiding the addition of an independent control box, making the structure of the entire deorbit sail device more compact, and helping to reduce the overall size and weight, which is very beneficial for reducing launch costs for aerospace equipment.

[0026] Furthermore, the design of perforations and openings plans the starting route for the deployment of the triangular canvas. The first corner point of the canvas is fixed to the outer wall of the storage box after being perforated. When the support and retraction mechanism pulls the second and triangular points, the canvas begins to stretch in an orderly manner from this stable starting point, avoiding confusion and entanglement in the early stage of deployment, allowing the sail surface to be accurately and smoothly deployed to the predetermined position, ensuring the stable performance of the subsequent resistance-enhancing function; the first corner point is fixed to the outer wall of the storage box. This position is relatively stable in the entire device structure and is not easily displaced by vibration and shaking caused by the retraction action. The firm fixed point provides a solid "anchor point" for the subsequent deployment and force of the canvas, ensuring that the sail surface deployment action is more stable in the complex space environment, and improving the reliability of the entire deorbit sail device. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0028] Figure 1 A schematic diagram of the overall structure of the three-dimensional drag-enhancing off-orbit sail provided by the present invention;

[0029] Figure 2 A schematic diagram of the structure of the support and retracting mechanism of the three-dimensional drag-enhancing off-orbit sail provided by the present invention;

[0030] Figure 3 A schematic diagram of the structure of the three-dimensional drag-enhancing off-orbit sail midsail storage device provided by the present invention;

[0031] Figure 4 A schematic structural diagram of a base in a three-dimensional drag-enhancing off-orbit sail provided by the present invention;

[0032] Figure 5 A schematic diagram of the structure of the three-dimensional drag-enhancing off-orbit sail provided by the present invention in a deployed state;

[0033] Figure 6 A schematic diagram of the folding of the triangular canvas in the three-dimensional drag-enhancing off-orbit sail provided by the present invention.

[0034] In the figure:

[0035] 10-base; 11-bottom plate; 12-bracket plate; 13-top connecting piece;

[0036] 20-supporting and retracting mechanism; 21-retracting bracket; 211-accommodating groove; 22-storage container; 23-ruler tape; 24-active friction shaft; 241-slave transmission gear; 242-transmission belt; 25-driven friction shaft; 26-swing plate; 261-propelling part; 27-driving motor; 271-main transmission gear; 28-limiting rod; 29-lateral limiting wheel;

[0037] 30 - sail storage device; 31 - storage box; 311 - perforation; 32 - bottom bracket; 33 - triangle sailcloth. DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] The purpose of the present invention is to provide a three-dimensional drag-increasing off-orbit sail to solve the problems existing in the prior art, facilitate repeated experiments on the ground, have low cost, have a self-stabilizing configuration, can increase drag in multiple directions, and can achieve higher synchronization and reliability of the sail surface.

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0041] Embodiment 1

[0042] This embodiment provides a three-dimensional drag-enhancing off-orbit sail, such as Figure 1 to Figure 6As shown, it includes a base 10 and at least two supporting and retracting mechanisms 20; a sail storage device 30 is arranged between two adjacent supporting and retracting mechanisms 20; each supporting and retracting mechanism 20 and the sail storage device 30 are fixedly arranged on the base 10, and each supporting and retracting mechanism 20 is circumferentially distributed around the axis of the base 10; the supporting and retracting mechanism 20 includes a retracting bracket 21, a storage container 22, a ruler 23 (whose structure is the same as the ruler 23 in the measuring tape, which can be retracted and retracted, and can maintain a certain shape when extended), an active friction shaft 24, a driven friction shaft 25 and a driving motor 27; the retracting bracket 21 is fixedly arranged on the base 10; the storage container 22 is arranged on the retracting bracket 21; one end of the ruler 23 can be retracted and stored in the storage container 22, and the free end of the ruler 23 can be extended and retracted along the inclined direction toward the axis direction away from the base 10, and the inclination direction is the same as the ruler 23 in the measuring tape. The oblique direction has an included angle with the axis of the base 10; the active friction shaft 24 and the driven friction shaft 25 are arranged opposite to each other, and the active friction shaft 24 and the driven friction shaft 25 are both rotatably arranged on the storage bracket 21; the ruler 23 is passed through the gap between the active friction shaft 24 and the driven friction shaft 25; the drive motor 27 is arranged on the storage bracket 21, and the output shaft of the drive motor 27 is used to drive the active friction shaft 24 to rotate; the sail storage device 30 has a storage cavity and an opening connected to the storage cavity; a triangular canvas 33 is placed in the storage cavity; the triangular canvas 33 has a first corner point, a second corner point and a third corner point; the first corner point is used to be fixed on the sail storage device 30, the second corner point is connected to the free end of the ruler 23 of the adjacent support and storage mechanism 20, and the third corner point is connected to the free end of the ruler 23 of another adjacent support and storage mechanism 20.

[0043] When the ruler tape 23 is extended and retracted along the inclined direction away from the axis of the base 10, and multiple circumferentially distributed support and retracting mechanisms 20 work together, when the sail surface is unfolded, these inclined ruler tapes 23 pull the triangular canvases 33 from different angles to form a pyramid shape as a whole. When the atmospheric flow hits the sail surface, the pyramid-shaped three-dimensional sail surface can not only achieve multi-directional resistance increase, but also provide a larger offset between the pressure center and the center of mass, and can provide a larger restoring torque when facing disturbances. In this way, the entire device will have a stronger anti-interference ability, that is, better attitude stability; each support and retracting mechanism 20 is driven by an independent drive motor 27 to actively friction The friction shaft 24 can set the same speed and torque parameters for each motor in the control algorithm, and monitor and adjust in real time through feedback elements such as encoders to ensure that all the tapes 23 are extended and retracted synchronously, so that the various parts of the sail surface can be coordinated to unfold and fold, and maintain good synchronization; the transmission of the support and retraction mechanism 20 is achieved by the active friction shaft 24, the driven friction shaft 25 and the drive motor 27. Compared with the release device of the pyrotechnics, it is purely electrically driven, has the advantages of safety, reusability, no impact on other components, and stepless speed change; compared with the release device based on memory alloy, it has the advantages of low cost and convenience for repeated experiments on the ground.

[0044] Among them, the relevant setting description of the support and retracting mechanism 20 is as follows:

[0045] In the optional scheme of this embodiment, it is more preferred that Figure 1 and Figure 5 As shown, the number of the supporting and retracting mechanisms 20 is 4; each supporting and retracting mechanism 20 is evenly distributed around the axis of the base 10 (in this case, the bottom plate 11 is a square plate, each supporting and retracting mechanism 20 is arranged at each corner, and the sail storage device 30 is arranged at each side). The structure that forms a quadrangular pyramid after unfolding is the preferred configuration. The airflow impact force is evenly dispersed to the entire sail surface, and the tension in each area is relatively balanced, avoiding the situation of local stress concentration. This can not only prevent the sail surface from being torn due to uneven force and extend the service life of the sail surface, but also maintain the stable three-dimensional configuration of the sail surface, ensuring the stability and sustainability of its drag-increasing effect.

[0046] In the optional scheme of this embodiment, it is more preferred that Figure 1 and Figure 2 As shown, the support and retracting mechanism 20 also includes a clamp; the clamp is arranged on the retracting bracket 21, and the driven friction shaft 25 is rotatably arranged on the clamp; the clamp can drive the driven friction shaft 25 to maintain a tendency to approach the active friction shaft 24. In the transmission mode where the tape 23 passes through the gap between the active friction shaft 24 and the driven friction shaft 25, the clamp allows the driven friction shaft 25 to continuously approach the active friction shaft 24, and can always maintain a suitable and stable clamping force between the two on the tape 23. This makes the friction force fluctuation very small during the friction transmission process, effectively avoiding the slippage of the tape 23 due to insufficient friction, ensuring that the power output by the drive motor 27 is stably and accurately transmitted to the tape 23, so that the retracting and releasing action of the tape 23 is continuous and smooth, which is very important for the precision of the deployment and folding of the sail. Accurate control is critical; since the three-dimensional drag-enhancing off-orbit sail is a multi-group support and retractable mechanism 20 working in coordination, the retraction and extension of the tapes 23 of all mechanisms must be highly synchronized to achieve a smooth and coordinated deployment and folding of the sail surface. The clamp ensures the stability of the friction transmission in each support and retractable mechanism 20, so that the speed and stroke of each group of tapes 23 in response to the instructions of the drive motor 27 tend to be consistent, thereby strengthening the synchronization of the deployment and folding actions of the entire sail surface, and avoiding uneven force on the sail surface, stretching deformation, or even tearing due to the lag or advance of individual tapes 23.

[0047] In the optional scheme of this embodiment, it is more preferred that Figure 1 and Figure 2As shown, the clamp includes two swing components; the two swing components are symmetrically arranged on the storage bracket 21; the swing component includes a swing plate 26 and a clamping spring; the swing plate 26 is rotatably arranged on the storage bracket 21 around a first axis; the swing plate 26 has a pushing portion 261 (the pushing portion 261 is a pushing block, and the pushing block has a shelf groove corresponding to the accommodating groove 211, one end of the clamping spring is placed in the shelf groove, and the other end of the clamping spring is placed in the accommodating groove 211), and a accommodating groove 211 is provided at a position corresponding to the pushing portion 261 on the storage bracket 21, the clamping spring is arranged in the accommodating groove 211, and one end of the clamping spring abuts against the pushing portion 261; the two ends of the driven friction shaft 25 are respectively connected to the corresponding swing plates 26 for rotation around a second axis, and the second axis is parallel to the first axis; after the compression spring is able to push the pushing portion 261, the swing plate 26 can drive the driven friction shaft 25 to move around the first axis to the side close to the active friction shaft 24. The compression springs on both sides each provide a driving force for the corresponding swing plate 26 and work together. Under the conditions of long-term operation, temperature changes, slight wear of components, etc., even if the elastic force of the spring on one side fluctuates slightly, the spring on the other side can assist in compensation, and still ensure that the driven friction shaft 25 applies a relatively balanced clamping force to the scale tape 23, which is of great significance for maintaining a stable friction transmission and ensuring the accuracy of the sail surface movement; after repeated use, the surfaces of the friction shaft and the scale tape 23 will inevitably produce a certain degree of wear, resulting in changes in the originally appropriate gap between the two. At this time, the compression spring can adapt to this wear condition by virtue of its own elasticity. As the gap increases, the spring pushes the swing plate 26 to rotate around the first axis, driving the driven friction shaft 25 to approach the active friction shaft 24, automatically making up the gap, maintaining a stable clamping force, and no frequent manual intervention and adjustment are required, thereby ensuring the long-term stable operation of the device.

[0048] Specifically, a limit rod 28 is fixedly provided on the retractable bracket 21 corresponding to the swing position of the swing plate 26 , and the limit rod 28 is used to limit the swing limit position of the swing plate 26 to ensure safe use.

[0049] In the optional scheme of this embodiment, it is more preferred that Figure 2As shown, the support and retracting mechanism 20 also includes a lateral limiting mechanism; the lateral limiting mechanism includes two lateral limiting wheels 29; the two lateral limiting wheels 29 are both located on one side of the active friction shaft 24 close to the free end of the ruler tape 23; each lateral limiting wheel 29 is rotatably set on the retracting bracket 21; the two lateral limiting wheels 29 are respectively located on both sides below the ruler tape 23; and each lateral limiting wheel 29 is in rolling contact with the ruler tape 23. The two lateral limit wheels 29 are respectively located on both sides below the ruler tape 23 and in rolling contact with it, defining a precise path for the extension and retraction movement of the ruler tape 23. During the retraction and extension process, the ruler tape 23 can only move along the direction defined by the lateral limit wheels 29 to avoid lateral deviation to the left or right, which is crucial for the off-track sail, because the accuracy of the unfolding and folding of the sail surface directly depends on whether the movement of the ruler tape 23 of each supporting and retracting mechanism 20 is accurate. Precise guidance can prevent the deformation and asymmetry of the sail surface caused by the deviation of the ruler tape 23, and ensure that the sail surface is unfolded and folded as expected by the design; the lateral limit wheels 29 and the ruler tape 23 adopt a rolling contact method. Compared with sliding friction, the rolling friction coefficient is extremely small. This rolling contact greatly reduces the friction between the two, reduces the risk of wear, fuzzing and even breakage due to friction, and extends the service life.

[0050] Specifically, a main transmission gear 271 is fixedly disposed on the output shaft of the driving motor 27 , a slave transmission gear 241 is fixedly disposed on the active friction shaft 24 , and a transmission belt 242 is sleeved on the main transmission gear 271 and the slave transmission gear 241 .

[0051] Specifically, both ends of the active friction shaft 24 are fixed on the retractable bracket 21 through a bearing fixing seat respectively.

[0052] The following are the relevant configuration instructions for the sail storage device 30:

[0053] Specifically, the triangular canvas 33 is a flexible sail surface material, which is a polyimide film with a thickness of 25 μm.

[0054] In the optional scheme of this embodiment, it is more preferred that Figure 1 and Figure 3As shown, the sail storage device 30 includes a storage box 31 and a bottom bracket 32; the storage box 31 is fixedly arranged at the upper end of the bottom bracket 32; the lower end of the bottom bracket 32 ​​is fixedly connected to the base 10; the storage box 31 has a storage cavity and an opening; the opening faces the side away from the axis of the base 10; a through hole 311 communicating with the storage cavity is arranged above the storage box 31; the first corner point of the triangular canvas 33 passes through the through hole 311 from the storage cavity and is fixedly connected to the outer wall of the storage box 31. The design of the through hole 311 and the opening plans a starting route for the unfolding of the triangular canvas 33. The first corner point of the canvas is fixed on the outer wall of the storage box 31 after passing through the hole 311. When the supporting and retracting mechanism 20 pulls the second and triangular points, the canvas begins to stretch in an orderly manner from this stable starting point, avoiding confusion and entanglement in the initial stage of deployment, allowing the sail surface to be accurately and smoothly deployed to the predetermined position, thereby ensuring the stable performance of the subsequent resistance-enhancing function; the first corner point is fixed on the outer wall of the storage box 31. This position is relatively stable in the structure of the entire device and is not easily displaced due to vibration and shaking caused by the retracting and releasing action. The firm fixing point provides a solid "anchor point" for the subsequent deployment and force application of the canvas, thereby ensuring that the sail surface deployment action is more stable in a complex space environment, thereby improving the reliability of the entire deorbit sail device.

[0055] Specifically, the storage box 31 has an isosceles trapezoidal cross-section structure, which is convenient for adapting to the selected folding method, and the opening is arranged on the long side of the isosceles trapezoid, so as to facilitate the smooth unfolding of the sail.

[0056] Specifically, in order to reduce the resistance during unfolding, the opening direction of the storage box 31 is consistent with the extension and retraction direction of the two tapes 23 of the triangular canvas 33 inside it.

[0057] In the optional scheme of this embodiment, it is more preferred that Figure 6As shown, the triangular canvas 33 is folded and placed in the storage cavity; the triangular canvas 33 is equidistantly Z-folded along the fold line parallel to the bottom edge of the triangular canvas 33 (Z-folding refers to a folding form in which convex creases and concave creases are staggered) to form a long strip; the long strip is unequally Z-folded from the middle to both sides to form a final folded shape (the final folded shape can match the storage cavity of the storage box 31). It adopts the above-mentioned Frog-leg folding method (which is an existing folding method), which provides an orderly process for the unfolding of the canvas. Cooperating with the pulling of the ruler tape 23 supporting the retracting and releasing mechanism 20, it can accurately and smoothly restore the original triangular shape of the sail surface, reduce the jamming and entanglement that may occur due to sudden large-scale unfolding, and ensure the reliability and synchronization of the unfolding of the sail surface; the unequally spaced Z-shaped folding makes the final shape of the canvas more flexible and changeable, and can better fit the irregular contour of the storage cavity and make full use of the corner space in the cavity. In actual engineering design, this reduces the strict requirements on the accuracy of the shape of the storage cavity, which is conducive to simplifying the mechanical design and manufacturing process of the device and indirectly controlling costs.

[0058] In the optional scheme of this embodiment, it is more preferred that the second corner point and the third corner point of the triangular canvas 33 are connected to the free end of the corresponding tape 23 through a tension spring (the tension spring is connected to the eyelet rings at the second corner point and the third corner point of the triangular canvas 33). The tension spring connection can act as a buffer component. When encountering an instantaneous impact force, the tension spring can quickly stretch, absorb and store part of the energy, and avoid the impact force being directly and rigidly transmitted to the connection between the canvas and the tape 23, preventing this place from being damaged due to sudden strong impact, ensuring the structural integrity, and maintaining the normal function of the off-track sail; in actual operation, since the performance of the drive motor 27 of each supporting and retracting mechanism 20 and the friction conditions of the transmission components are difficult to be completely consistent, the tension applied to the corner points of the canvas by different tapes 23 may be slightly different, and the tension spring can adapt to this. In the case of uneven tension, when the tension of the ruler tape 23 on one side is slightly larger, the corresponding tension spring will be stretched appropriately, otherwise it will retract and automatically adjust to make the forces on the two corners of the canvas as even as possible, so as to ensure the smooth deployment of the sail surface, maintain a stable three-dimensional configuration, and improve the stability of the drag-increasing effect; compared with the rigid connection, the tension spring gives the connection link a certain flexibility. In the early stage of the sail surface deployment, the tension spring is first stretched to drive the corner point of the canvas to move in a gentle manner, giving the entire sail surface a buffer start process to avoid the canvas from being torn or stuck at the folded part due to excessive initial tension.

[0059] Among them, the relevant setting instructions about the base 10 are:

[0060] In the optional scheme of this embodiment, it is more preferred that Figure 1 , Figure 4 and Figure 5As shown, the base 10 includes a bottom plate 11 and a plurality of support plates 12; each support plate 12 is evenly fixed on the bottom plate 11 around the axis of the bottom plate 11; each support and retracting mechanism 20 is fixed on a support plate 12. The plurality of support plates 12 are evenly distributed around the axis of the bottom plate 11, so that the tension and stress carried by each support and retracting mechanism 20 can be evenly dispersed on the bottom plate 11. When the deorbit sail is deployed, the sail surface is subjected to airflow resistance, and the corresponding support and retracting mechanism 20 is pulled. The tension is dispersed and transmitted through the support plates 12 to avoid stress concentration in a certain place, which can effectively prevent the base 10 from deformation and damage, provide a solid and reliable support foundation for the entire device, and ensure the long-term stable operation of the deorbit sail.

[0061] Specifically, the bracket plate 12 has an inclined surface for supporting the installation of the retracting mechanism 20, and its inclination angle is set according to the best effect of the optimal configuration. For example, the four-sided pyramid configuration with an angle of 63 degrees of the tape 23 obtained by numerical simulation is the global optimal configuration.

[0062] Specifically, the top of each bracket plate 12 is fixedly connected to a top connecting member 13 to increase the stability of each bracket plate 12 .

[0063] Specifically, the bottom plate 11 may be provided with necessary weight-reducing holes for lightweight design.

[0064] Among them, about other related settings description:

[0065] In the optional scheme of this embodiment, it is more preferred to further include a controller, which is in communication connection with the drive motors 27 of each support and retracting mechanism 20; the controller is fixedly arranged on the bottom plate 11 in the enclosed space of each bracket plate 12. The controller is in communication connection with each drive motor 27, just like building a "central command center" for the entire three-dimensional drag-enhancing deorbit sail. It can centrally send instructions, accurately set the speed, steering, start and stop time of each drive motor 27, and allow the ruler tape 23 of each support and retracting mechanism 20 to be retracted synchronously, thereby ensuring that the unfolding and folding actions of the sail surface are uniform; fixing the controller on the bottom plate 11 in the enclosed space of the bracket plate 12 cleverly utilizes the originally idle space inside the base 10, avoids the additional independent control box, makes the structure of the entire deorbit sail device more compact, and helps to reduce the overall volume and weight, which is very helpful for reducing the launch cost for aerospace equipment.

[0066] Specifically, it also includes other necessary components, such as a power supply (Format (ACE) 6s series model aircraft battery), an electric speed controller (RoboMaster electric speed controller center board), and a controller (DJI RoboMaster C-type development board). The power supply provides power to the electric speed controller, and the electric speed controller adjusts the speed and direction of the drive motor 27 according to the control signal sent by the controller, so that the drive motor 27 generates mechanical power; the controller is responsible for receiving user remote control commands and generating control signals to control the operation of the electric speed controller.

[0067] The present invention uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core ideas of the present invention. At the same time, for those skilled in the art, according to the ideas of the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A three-dimensional drag-enhancing off-orbit sail, characterized in that: It comprises a base and at least two supporting and retracting mechanisms; a sail storage device is arranged between two adjacent supporting and retracting mechanisms; Each of the supporting and retracting mechanisms and the sail storage device is fixedly arranged on the base, and each of the supporting and retracting mechanisms is circumferentially distributed around the axis of the base; The supporting and retracting mechanism comprises a retracting bracket, a storage container, a ruler tape, an active friction shaft, a driven friction shaft and a driving motor; the retracting bracket is fixedly arranged on the base; the storage container is arranged on the retracting bracket; one end of the ruler tape can be wound and stored in the storage container, and the free end of the ruler tape can be extended and retracted along an inclined direction in a direction away from the axis of the base, and the inclined direction has an angle with the axis of the base; the active friction shaft and the driven friction shaft are arranged opposite to each other, and the active friction shaft and the driven friction shaft are both rotatably arranged on the retracting bracket; the ruler tape is inserted in a gap between the active friction shaft and the driven friction shaft; the driving motor is arranged on the retracting bracket, and the output shaft of the driving motor is used to drive the active friction shaft to rotate; The sail storage device has a storage cavity and an opening connected to the storage cavity; a triangular canvas is placed in the storage cavity; the triangular canvas has a first corner point, a second corner point and a third corner point; the first corner point is used to be fixed on the sail storage device, the second corner point is connected to the free end of the ruler tape of the adjacent supporting and retracting mechanism, and the third corner point is connected to the free end of the ruler tape of another adjacent supporting and retracting mechanism.

2. The three-dimensional drag-enhancing off-track sail according to claim 1, characterized in that: The supporting and retracting mechanism also includes a clamp; the clamp is arranged on the retracting bracket, and the driven friction shaft is rotatably arranged on the clamp; the clamp can drive the driven friction shaft to maintain a tendency to approach the active friction shaft.

3. The three-dimensional drag-enhancing off-track sail according to claim 2, characterized in that: The clamp comprises two swing assemblies; the two swing assemblies are symmetrically arranged on the retractable bracket; The swing assembly includes a swing plate and a clamping spring; the swing plate is rotatably arranged on the retractable bracket around a first axis; the swing plate has a pushing portion, a receiving groove is arranged on the retractable bracket at a position corresponding to the pushing portion, the clamping spring is arranged in the receiving groove, and one end of the clamping spring abuts against the pushing portion; The two ends of the driven friction shaft are respectively connected to the corresponding swing plates for rotation around a second axis, and the second axis is parallel to the first axis; after the compression spring can push the pushing part, the swing plate can drive the driven friction shaft to move around the first axis to the side close to the active friction shaft.

4. The three-dimensional drag-enhancing off-track sail according to claim 1, characterized in that: The supporting and retracting mechanism also includes a lateral limiting mechanism; The lateral limiting mechanism includes two lateral limiting wheels; the two lateral limiting wheels are both located on one side of the active friction shaft close to the free end of the tape; each of the lateral limiting wheels is rotatably arranged on the retractable bracket; The two lateral limiting wheels are respectively located at two sides below the ruler tape; and each of the lateral limiting wheels is in rolling contact with the ruler tape.

5. The three-dimensional drag-enhancing off-track sail according to claim 1, characterized in that: The number of the supporting and retracting mechanisms is 4; each of the supporting and retracting mechanisms is evenly distributed circumferentially around the axis of the base.

6. The three-dimensional drag-enhancing off-orbit sail according to claim 1, characterized in that: The triangular canvas is folded and placed in the storage cavity; The triangular canvas is folded in an equidistant Z shape along a fold line parallel to the bottom edge of the triangular canvas to form a long strip; the long strip is folded in an unequal Z shape from the middle to both sides to form a final folded shape.

7. The three-dimensional drag-enhancing off-track sail according to claim 1, characterized in that: The second corner point and the third corner point of the triangular canvas are both connected to the corresponding free ends of the ruler tape via a tension spring.

8. The three-dimensional drag-enhancing off-track sail according to claim 1, characterized in that: The base includes a bottom plate and a plurality of bracket plates; Each of the bracket plates is uniformly fixed on the bottom plate in the circumferential direction around the axis of the bottom plate; Each of the supporting and retracting mechanisms is fixedly arranged on one of the bracket plates.

9. The three-dimensional drag-enhancing off-track sail according to claim 8, characterized in that: It also includes a controller, which is communicatively connected to the drive motor of each of the supporting and retracting mechanisms; The controller is fixedly arranged on the bottom plate in the space enclosed by each of the bracket plates.

10. The three-dimensional drag-enhancing off-orbit sail according to claim 1, characterized in that: The sail storage device comprises a storage box and a bottom bracket; the storage box is fixedly arranged at the upper end of the bottom bracket; the lower end of the bottom bracket is fixedly connected to the base; The storage box comprises the storage cavity and the opening; the opening faces the side away from the axis of the base; a through hole connected to the storage cavity is provided on the top of the storage box; the first corner point of the triangular canvas passes through the through hole from the storage cavity and is fixedly connected to the outer wall of the storage box.

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