Satellite grappling anchor based on flexible capture mechanism

Abstract

The application provides a satellite capture anchor claw based on a flexible capture mechanism. The satellite capture anchor claw comprises a shell, a connecting rod, a baffle, a baffle fixing rod, a sliding block, an anchor tail, a fixed pulley, a finger chain and a traction rope. The shell is composed of an anchor head and an anchor body, and the finger chain is rotatably connected by a plurality of finger joints. The anchor body and the anchor tail are both provided with cavities, and four limiting guide rails are arranged on the inner walls of the cavities. The sliding block is fixedly connected with the connecting rod, the first sliding block is arranged in the anchor body, and the second sliding block is arranged in the anchor tail. The first baffle is fixed on the rear end surface of the anchor body, and the second baffle is fixed on the front end surface of the anchor tail. The baffle and the limiting guide rail limit the sliding block to move forward and backward in the cavity. One end of the traction rope is fixed on the barbed finger joint at the end of the finger chain, and the other end is fixed on the finger chain support plate of the anchor tail. During the recovery process, the anchor tail and the shell are relatively displaced under the action of the recovery rope, the traction rope is pulled tight, and the traction finger chain is bent to tightly hold the target satellite. The satellite capture anchor claw has the advantages of simple structure, low cost, convenient operation and the capability of capturing the space satellite.

Description

Technical Field

[0001] The present invention relates to the field of aerospace, and in particular to a satellite capturing anchor claw based on a flexible capturing mechanism. Background Art

[0002] With the passage of time, the division of power in outer space has also changed. With the rise of commercial spaceflight, more and more countries and private entities are becoming increasingly involved in space activities. The active participation of private entities and the rise of commercial spaceflight are propelling our space sector into a new era.

[0003] The development and utilization of space resources is a new frontier in the current great power struggle and a key area of ​​technological competition. It carries the hope for the sustainable development of human civilization and is a major strategic issue concerning my country's future development. With the rapid development of my country's economy and science and technology, and the significant increase in its comprehensive national strength, my country has placed increasing emphasis on the exploration and collection of outer space resources. China is one of the few countries globally capable of developing space resources. Currently, the proactive removal of space debris remains a common challenge and difficulty facing the global aerospace industry, and a hot topic for the future. Both domestic and foreign researchers have explored the capture of space debris. The existing capture mechanisms can be roughly divided into three categories: the first category is the rigid connection capture mechanism, which mainly relies on rigid robotic arms to capture space debris. Representative research results include the DEOS project proposed by Germany's DLR, the FREND project in the United States, and the US DARPA "Phoenix" program; the second category is the flexible connection capture mechanism, which captures debris by connecting structures such as nets and rope-capture mechanisms with flexible structures. Representative research includes the European Space Agency's harpoon scheme and rope net capture method; the third category is non-contact removal, which applies a small thrust to the debris, such as electrostatic force, laser, ion beam, etc., to change the orbit of the debris and achieve deorbit removal of the debris.

[0004] Domestic research on capturing space satellites has also been conducted, with most using flexible connection mechanisms, rope net capture, and rope-capture mechanisms. However, most existing capture mechanisms are complex, difficult to manufacture, and expensive, making them unsuitable for mass production. This results in low satellite capture efficiency and low profitability. Summary of the Invention

[0005] The object of the present invention is to provide a satellite capture anchor claw which has a simple structure, low cost, is suitable for batch production and is reusable and can realize efficient and firm capture of satellites.

[0006] The technical solution for achieving the purpose of the present invention is: a satellite capture anchor claw based on a flexible capture mechanism, including a shell, a connecting rod, an anchor tail, two sliders, two baffles, four fixed pulleys, four finger chains, four traction ropes and eight baffle fixing rods; the shell is composed of an anchor head and an anchor body from front to back, the anchor body is cylindrical, and a first cavity is opened from the rear end to the front, the first baffle is fixed to the bottom surface of the anchor body, four evenly distributed limiting guide rails are provided inside the first cavity to cooperate with the positioning notch to achieve positioning, the anchor tail is cylindrical, and a second cavity is opened from the front end to the back, and the inner wall of the second cavity is provided with four The limiting guide rail cooperates with the positioning notch to achieve positioning. The first slider is placed in the first cavity and is fixedly connected to one end of the connecting rod. The connecting rod passes through the two baffles and extends into the second cavity to be fixedly connected to the second slider placed on the anchor tail. The second baffle is fixed to the front end surface of the anchor tail through four fixing rods. Four groups of long strips are evenly distributed on the outer surface of the anchor body. Each group of long strips is provided with a fixed pulley and a finger chain. Each fixed pulley is rotatably connected to the anchor body and the front end of the finger chain through a pulley mounting rod. One end of the traction rope is fixedly connected to the hook knuckle of the finger chain. The traction rope passes through the groove of the finger chain, bypasses the fixed pulley and is fixed to the finger chain support block on the anchor tail.

[0007] Compared with the prior art, the present invention has the following effects:

[0008] (1) The present invention is based on the study and innovation of the existing flexible capture mechanism. It adopts the shell separation method on the existing small-sized flying anchor structure to realize the contraction of the towing rope, and further realizes the fixation of the satellite capture anchor claw to the satellite. The present invention only needs to be launched and recovered after the launch, and does not require additional control. For satellites of different sizes, the size of the flying anchor can be appropriately scaled. For large satellites, the number of finger chains and towing ropes can be appropriately increased to achieve better grasping and recovery purposes. Under the condition that there is no obvious deformation of the anchor head and no obvious breakage of the towing rope, the satellite capture anchor claw can be reused.

[0009] (2) The present invention is simple to operate, easy to process, simple to assemble, low in cost, and easy to understand and operate. It can capture satellites in space, especially spherical satellites that are difficult to capture. The anchor head and the four finger chains have the function of locking space debris. The multiple locking makes it difficult for the satellite to fall off. Each ordinary finger joint on the finger chain is provided with a rotation limit. The finger chain can only bend forward, and the rotation angle of adjacent finger joints is certain to prevent two unexpected situations: the finger chain bends in the opposite direction of the target satellite when the traction rope is tightened, and the finger chain bends excessively in advance when the traction rope is tightened.

[0010] (3) The present invention adopts a separate anchor body structure. During the recovery process, the anchor tail and the shell undergo relative displacement. The movement of the anchor tail drives the tightening of the traction rope, and the traction rope drives the finger chain to bend forward, so that the finger chain holds the target satellite tightly. During the recovery process, the displacement between the anchor tail and the anchor body can only increase and cannot decrease, thereby achieving the purpose of the satellite capture anchor claw being able to firmly grasp the target satellite.

[0011] (4) By using 3D printing technology to process a proportional satellite capture anchor claw physical model, the performance of the satellite capture anchor claw structure was tested, and the satellite capture anchor claw was fine-tuned. The test structure showed that the satellite capture anchor claw can normally and effectively grasp objects. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 A three-dimensional diagram of a satellite capture anchor claw based on a flexible capture mechanism in one embodiment.

[0013] Figure 2 A half-section perspective view of a satellite capture anchor claw based on a flexible capture mechanism in one embodiment.

[0014] In the figure: 1-housing, 2-connecting rod, 3-baffle, 4-baffle fixing rod, 5-slider, 6-anchor tail, 7-fixed pulley, 8-finger chain, 9-traction rope.

[0015] Figure 3 2 is a perspective view of a housing in one embodiment.

[0016] Figure 4 FIG. 1 is a perspective view of an anchor tail in one embodiment.

[0017] Figure 5 A schematic diagram of mechanical analysis of a finger chain in one embodiment.

[0018] Figure 6 It is a three-dimensional view of a common knuckle of a finger chain in one embodiment.

[0019] Figure 7 It is a three-dimensional diagram of the sliding structure in one embodiment.

[0020] Figure 8 This is an exploded view of a satellite capture anchor claw penetrating the main structure in one embodiment. DETAILED DESCRIPTION

[0021] The satellite capture anchor claw based on the flexible capture mechanism of the present invention will be further described in detail below in conjunction with the accompanying drawings and working principles of the present invention.

[0022] Combine Figures 1 to 8The present invention provides a satellite capture anchor claw based on a flexible capture mechanism, including a shell 1, a connecting rod 2, an anchor tail 6, two baffles 3, two sliders 5, four fixed pulleys 7, four finger chains 8, four traction ropes 9 and eight baffle fixing rods 4. The shell 1 is composed of an anchor head and an anchor body from front to back, and is formed through integral processing. The anchor head is conical, and the maximum diameter of the anchor head is larger than the maximum diameter of the anchor body. The anchor body is cylindrical, and a first cavity is opened from the rear end face to the front. Four limiting guide rails are evenly distributed on the inner wall of the first cavity. The baffle 3 is pie-shaped, and a number of positioning notches are evenly distributed on its circumferential outer wall. The first baffle 3 is fixed to the bottom surface of the anchor body by four fixing rods. The inner wall of the first cavity is provided with four mutually parallel first limiting guide rails to cooperate with the positioning notches to achieve positioning. The slider 5 is a circular ring; a number of positioning notches are evenly distributed on its circumferential outer wall. The anchor tail 6 is cylindrical, and a second cavity is opened from the front end face to the back. Four limiting guide rails are evenly distributed on the inner wall of the second cavity. The limiting guide rails cooperate with the positioning notches on the baffle and the slider to limit the relative rotation of the shell 1 and the anchor tail 6, so as to prevent the satellite capture anchor claw from tightening the traction rope 9 in advance during flight and prevent different traction ropes 9 from being entangled together. The first slider 5 is placed in the first cavity and is fixedly connected to one end of the connecting rod 2. The connecting rod 2 passes through the two baffles 3 and extends into the second cavity and is fixedly connected to the second slider 5 placed in the second cavity. The second baffle 3 is fixed to the front end face of the anchor tail 6 by four baffle fixing rods 4. Four groups of long strips are evenly distributed on the outer surface of the anchor body, and each group of long strips is provided with a fixed pulley 7 and a finger chain 8. Each fixed pulley 7 is rotatably connected to the anchor body and the front end of the finger chain 8 through a pulley mounting rod. The fixed pulley can change the direction of the force. One end of the traction rope 9 is fixedly connected to the hook knuckle of the finger chain 8. The fixing hole of the traction rope 9 on the hook knuckle is located above the axis of the hook knuckle to ensure that when the traction rope 9 is tightened, the finger chain 8 can be smoothly bent and grasp the satellite. The traction rope 9 passes through the groove of the finger chain 8, bypasses the fixed pulley 7 and is fixed to the finger chain 8 support block on the anchor tail 6.

[0023] During the satellite capture anchor's penetration of the target satellite, in the first stage, during launch, the anchor tail 6 propels the entire satellite capture anchor forward, with the four finger chains 8 of the satellite capture anchor clinging tightly to the four finger chain 8 support plates of the anchor tail 6. In the second stage, the satellite capture anchor begins to contact the target satellite, decelerating the main body of the satellite capture anchor. The anchor head penetrates the target satellite, and the finger chains 8 continue to move forward due to inertia. Finally, the satellite capture anchor and the satellite move at the same speed. In the third stage, the recovery rope tightens the anchor tail 6, generating a relative velocity between the anchor tail 6 and the housing 1. Under the action of the first slider 5 and the connecting rod 2, the anchor tail 6 and the housing 1 produce relative displacement, tightening the traction rope 9. Driven by the traction rope 9, the finger chains 8 continue to bend, finally securing the target satellite. During the recovery process, the distance between the anchor tail 6 and the housing 1 does not decrease, and the traction rope 9 remains taut and does not loosen, ensuring that the finger chains 8 maintain a tight grip on the target satellite. Driven by the recovery rope, the satellite capture anchor pulls the target satellite backward.

[0024] Furthermore, the finger chain 8 consists of several ordinary finger joints and one barbed finger joint from front to back. Adjacent finger joints are rotatably connected by a rotating shaft. The lowest ordinary finger joint is rotatably connected to the barbed finger joint by a rotating shaft. The rotation between the two finger joints is limited by a rotation limit on each ordinary finger joint. The finger chain 8 can only bend forward, and the rotation angle of adjacent finger joints is fixed to prevent the finger chain 8 from bending in the opposite direction of the target satellite when the towing rope 9 is tightened, and the finger chain 8 from bending prematurely when the towing rope 9 is tightened. A barbed finger joint is added at the end of each finger chain 8 to increase the anchoring force of the satellite capture anchor claw on the satellite.

[0025] An embodiment provided by the present invention is as follows Figures 2 to 4 As shown, the shell 1 includes an anchor head, an anchor body and a limiting guide rail, which are formed through integral processing. During the penetration and fixation process, the two sliders 5 will move forward and backward along the inner wall of the anchor body and the inner wall of the anchor tail 6 respectively, and cannot rotate. The baffle 3 has a limiting effect on the slider 5. The shell 1 and the anchor tail 6 can achieve relative displacement under the action of the slider 5, the connecting rod 2 and the baffle 3. Furthermore, the traction rope 9 is tightened, and the traction rope 9 pulls the finger chain 8 to bend forward and hold the target satellite tightly.

[0026] After the satellite capture anchor claw penetrates the target satellite, the anchor tail 6, driven by the recovery rope, produces relative displacement with the shell 1, causing the traction rope 9 to be tightened, thereby driving the finger chain 8 to bend forward and hold the target satellite tightly. In addition, since the maximum diameter of the anchor head is larger than the maximum diameter of the anchor body, the anchor head generates an anchoring force on the target satellite similar to an expansion bolt.

[0027] The principle of the present invention is similar to the principle of a space harpoon capturing space debris. The satellite capture anchor claw is launched at a very high speed through a power launch device (such as a cylinder, a gunpowder launch device, etc.), and then penetrates and fixes the target satellite. Before launching the satellite capture anchor claw, the finger chain 8 should be manually straightened, which can not only maintain flight stability during flight, but also prevent the finger chain 8 from bending prematurely during flight and penetration. In the process of penetrating target debris, the shell 1 collides with and penetrates the target satellite, and part of the kinetic energy of the shell 1 is converted into the kinetic energy of the target satellite, and part is converted into the deformation energy of the shell 1 and the target satellite and the shear work done during penetration. The kinetic energy of the shell 1 is reduced and the speed is reduced, so that the finger chain 8 rotates forward due to inertia during the penetration process; the anchor tail 6 moves backward under the pull of the recovery rope, and while the anchor tail 6 and the shell 1 produce relative displacement, the traction rope 9 is also tightened, which further causes the finger chain 8 to bend, and then the finger chain 8 is pulled to hold the target satellite tightly, thereby achieving the capture of the target satellite.

[0028] The satellite capture anchor claw of the present invention is subjected to mechanical analysis, and the satellite capture anchor claw satisfies the following formula:

[0029] 0.5m p v0 2 =E pp +E tp +E s +0.5(m p +m t )v 2 (Formula 1)

[0030] m p v0=(m p +m t )v (Formula 2)

[0031]

[0032]

[0033] σ x =L×(n-1)×(1-cosθ) (Equation 5)

[0034] L T =2×L t +L×(n-1)×(1-cosθ) (Equation 6)

[0035] Where: m p is the total mass of the satellite capture anchor claw, m t is the mass of the target satellite, E pp is the deformation energy of the satellite capture anchor claw, E tp is the deformation energy of the satellite, E sis the shear work done by the satellite capture anchor claw penetrating the target satellite, v0 is the initial velocity of the satellite capture anchor claw, v is the residual velocity of the satellite capture anchor claw, θ is the rotation angle of the finger joint, n is the number of ordinary finger joints in a single finger chain 8, is the angle between two common knuckles; R h is the standard capture radius of the satellite capture anchor claw under ideal conditions, R is the rotation radius of the finger joint, σ x is the displacement of the traction rope 9 during the capture process of the satellite capture anchor claw, L is the effective length of the ordinary finger joint, and L T is the length of connecting rod 2, L t is the connection length between the connecting rod 2 and the slider 5.

[0036] The space environment is unpredictable and may encounter extreme conditions such as ultra-high temperature, ultra-low temperature, strong electromagnetic field, and weightlessness. Electronic control equipment is prone to loss of control under such extreme conditions, which brings troubles to satellite capture work. In the process of the satellite capture anchor claw penetrating the space satellite, the difference between the maximum diameter of the anchor head and the maximum diameter of the anchor body is used to enable the anchor head to generate an anchoring force on the target satellite. In addition, the relative displacement of the shell 1 and the anchor tail 6 drives the traction rope 9 to tighten, so that the finger chain 8 grasps the target satellite. Furthermore, during the recovery process, the distance between the shell 1 and the anchor tail 6 will only increase and not decrease. The satellite capture work is achieved through the mechanical structure, thereby ensuring that the satellite capture anchor claw can still have a high probability of grasping the target satellite under different extreme conditions in space.

Claims

1. A satellite capture anchor claw based on a flexible capture mechanism, characterized by: The invention comprises a shell (1), a connecting rod (2), an anchor tail (6), two baffles (3), two sliders (5), four fixed pulleys (7), four finger chains (8), four traction ropes (9) and eight baffle fixing rods (4); the shell (1) is composed of an anchor head and an anchor body in sequence from front to back, the anchor body is cylindrical, and a first cavity is opened from the rear end to the front, the baffle (3) is a low circular cake shape, and a plurality of positioning notches are evenly distributed on the circumferential outer wall thereof, the first baffle (3) is fixed to the bottom surface of the anchor body through four baffle fixing rods (4), the inner wall of the first cavity is provided with four mutually parallel first limiting guide rails to cooperate with the positioning notches to achieve positioning, the slider (5) is annular; a plurality of positioning notches are evenly distributed on the circumferential outer wall thereof, the anchor tail (6) is cylindrical, and a second cavity is opened from the front end to the rear, and the inner wall of the second cavity is provided with four second limiting guide rails. The guide rail is used to match the positioning notch to achieve positioning. The first slider (5) is placed in the first cavity of the shell (1) and is fixedly connected to one end of the connecting rod (2). The connecting rod (2) passes through the two baffles (3) and extends into the second cavity of the anchor tail (6) to be fixedly connected to the second slider (5) placed in the anchor tail (6). The second baffle (3) is fixed to the front end surface of the anchor tail (6) through four baffle fixing rods (4). Four groups of long strips are evenly distributed on the outer surface of the anchor body. Each group of long strips is provided with a fixed pulley (7) and a finger chain (8). Each fixed pulley (7) is rotatably connected to the anchor body and the front end of the finger chain (8) through a pulley mounting rod. One end of the traction rope (9) is fixedly connected to the hook knuckle at the end of the finger chain (8). The traction rope (9) passes through the groove of the finger chain (8) and bypasses the fixed pulley (7) to be fixedly connected to the finger chain support block on the anchor tail (6); The maximum diameter of the anchor head is greater than the diameter of the anchor body; during the launch process, the anchor tail (6) pushes the entire satellite capture anchor claw to move forward, and the four finger chains (8) of the satellite capture anchor claw are tightly attached to the four finger chains (8) support plates of the anchor tail (6); during the recovery process of the satellite capture anchor claw, the anchor tail (6) is pulled to move backward, and the baffle (3) fixed on the anchor tail (6) gradually approaches the second slider (5), driving the second slider (5) and the connecting rod (2) to move backward together, and the four traction ropes (9) fixed on the anchor tail (6) are gradually tightened, and the four finger chains (8) are gradually bent and tightened, and finally the first slider (5) placed in the first cavity contacts the baffle (3) and drives the shell (1) to move backward together, the four traction ropes (9) are completely tightened, and the four finger chains (8) hold the satellite tightly, and under the drive of the recovery rope, the satellite is pulled to move backward together; The finger chain (8) is composed of a plurality of common finger joints and a barbed finger joint from front to back, and the adjacent two finger joints are connected by a rotating shaft. The common finger joint at the bottom is connected by a rotating shaft to the barbed finger joint, and the rotation between the two finger joints is smooth.

2. The satellite capture anchor claw based on the flexible capture mechanism according to claim 1, characterized in that: Each common finger joint is provided with a rotation limit, and the finger chain (8) can only bend forward, and the rotation angle of adjacent finger joints is constant. The rotation angle θ is related to the total number n of common finger joints on each finger chain (8), and the specific relationship is:

3. The satellite capture anchor claw based on the flexible capture mechanism according to claim 2, characterized in that: The finger chain (8) bends under the pulling of the rope, and the tightened length of the rope is equal to the length of the connecting rod.

4. The satellite capture anchor claw based on the flexible capture mechanism according to claim 3, characterized in that: The satellite capture anchor claw satisfies the following formula: 0.5m p v0 2 = E pp + E tp + E s + 0.5(m p + m t )v 2 (Equation 1) m p v0 = (m p + m t )v (Equation 2) s x =L×(n-1)×(1-cosθ) (Equation 5) L T = 2 × L t + L × (n - 1) × (1 - cosθ) (Equation 6) Where: m p is the total mass of the satellite capture anchor claw, m t is the mass of the target satellite, E pp is the deformation energy of the satellite capture anchor claw, E tp is the deformation energy of the satellite, E s is the shear work done by the satellite capture anchor claw penetrating the target satellite, v0 is the initial velocity of the satellite capture anchor claw, v is the residual velocity of the satellite capture anchor claw, θ is the rotation angle of the finger joint, n is the number of ordinary finger joints in a single finger chain (8), is the angle between two common knuckles; R h is the standard capture radius of the satellite capture anchor claw under ideal conditions, R is the rotation radius of the finger joint, σ x is the displacement of the traction rope (9) during the capture process of the satellite capture anchor claw, L is the effective length of the ordinary knuckle, and L T is the length of the connecting rod (2), L t is the connection length between the connecting rod (2) and the slider (5).

Images