CN110884689A - Optical imaging satellite bottom light shield unfolding system - Google Patents

Abstract

The invention provides an optical imaging satellite bottom light shield unfolding system which comprises a bottom light shield stretching mechanism (9) and a bottom light shield (8) arranged on the bottom light shield stretching mechanism, wherein the bottom light shield stretching mechanism (9) can open the bottom light shield (8) in the circumferential direction in a folding mode so as to shield a main reflector. The optical imaging satellite bottom light shield unfolding system utilizes the folding and stretching mechanism to carry out on-orbit unfolding, so that the structural size of the satellite meets the requirements of a fairing.

Description

An optical imaging satellite bottom hood deployment system

technical field

The invention belongs to the technical field of satellites, and in particular relates to an optical imaging satellite bottom hood deployment system.

Background technique

Optical imaging satellites deployed in the Geostationary Orbit (GEO) can realize long-term continuous monitoring and fast access imaging suitable for the ground. When the satellite operates in the GEO orbit, it will be affected by stray light such as sunlight, and the off-axis will be affected. The stray light enters the optical system of the satellite through radiation, and finally reaches the focal plane position of the camera through the primary and secondary mirrors, which will cause the target signal-to-noise ratio and image plane contrast of the satellite's optical system to decrease, and the target image is blurred, thereby affecting the satellite. In this regard, in order to eliminate the influence of stray light such as sunlight on the satellite optical system, it is necessary to install a hood structure on the satellite. The hood structure at the bottom of the optical primary mirror is usually a circular fixed structure, covering the bottom of the satellite primary mirror.

The bottom hood structure of the traditional satellite optical lens is usually fixed, while the GEO high-resolution optical imaging satellite, in order to achieve its high resolution, requires a large aperture for its satellite main mirror, which needs to be divided at the beginning of the launch. Block or foldable, and have the ability to deploy on-orbit, the traditional fixed hood cannot be folded and unfolded with the folding and unfolding of the satellite main reflector.

SUMMARY OF THE INVENTION

The invention provides an optical imaging satellite bottom hood unfolding system, which utilizes a folding and stretching mechanism for on-orbit unfolding, so that the satellite structure size meets the requirements of the fairing.

The technical scheme of the present invention includes:

An optical imaging satellite, comprising a primary and secondary mirror telescopic system, a bottom hood unfolding system, a side hood unfolding system, a conformal structure, an optical camera and each satellite subsystem, wherein:

The primary and secondary mirror telescopic system includes a primary mirror that can be stretched and opened in the circumferential direction, a secondary mirror stretch arm that can be stretched in the length direction, and a secondary mirror installed at the end of the secondary mirror stretch arm. The secondary mirror stretch arm and the main reflector The center of the mirror is connected, and the main mirror is opened to form a concave spherical surface;

The bottom hood unfolding system is arranged on the outer side of the main reflector of the primary and secondary mirror telescopic system, and includes a bottom hood stretching mechanism and a bottom hood installed on it. The bottom hood opens to shield the main reflector;

The side hood deployment system includes a top telescopic collar support rod structure arranged at the top end of the secondary mirror extension arm, a bottom folding rod arranged between the primary mirror and the bottom shade extension mechanism, and a side surface connected between the two The hood, the top telescopic collar support rod structure and the bottom folding rod can be opened in the circumferential direction with the extension of the secondary mirror extension arm, and the side visor is stretched and covered outside the secondary mirror extension arm;

The conformal structure is arranged at the end of the extension arm of the secondary mirror, and concentrically connects the secondary mirror and the communication antenna, wherein the communication antenna is located outside the secondary mirror;

The optical camera is installed in the secondary mirror extension arm of the primary and secondary mirror extension system.

The satellite subsystem includes an attitude control system, an orbit control system, a power supply and distribution system, a thermal control system, a data management system, a camera and image processing system, and a communication system;

The optical camera, the propellant storage tank of the propulsion system and other subsystems are fixed in the frame unit of the extension arm of the secondary mirror through the fixed structure;

The nozzle of the satellite propulsion subsystem is installed at the bottom of the satellite, and a hexagonal ring is fixed by six fixed brackets connected to the base of the main mirror, and the hexagonal ring is fixed on the periphery of the nozzle of the satellite propulsion subsystem to fix the nozzle;

The propellant storage tank of the propulsion subsystem is connected to the nozzle through a pipeline.

Among them, the primary and secondary mirror telescopic system:

The main reflector includes a main mirror base, a number of spaced-arranged main mirror support frames and mirror film traction frames that are evenly articulated on the circumference of the main mirror base by self-locking joints driven by motors, and connected to the main mirror support frame and mirror film traction frame. The optical main mirror film on the frame, and the motor for controlling the movement of the main mirror support frame and/or the mirror film traction frame.

The main mirror support frame and the mirror film traction frame are respectively provided with two.

The optical main mirror film can be an integral annular film, and the main mirror support frame and the mirror film traction frame are bonded to the surface of the optical main mirror film; it can also be a fan-shaped structure design, and the two sides of the optical main mirror film are respectively The adjacent main mirror support frame and the mirror film traction frame are connected.

The optical primary mirror film material is a piezoelectric material lens made of polyvinylidene fluoride.

When the main mirror is retracted, the optical main mirror film is folded and stored in a zigzag shape.

The secondary mirror extension arm is composed of a plurality of frame units. Both ends of each frame unit are triangular frame structures. The middle is a transverse rod that can be folded and stored inward. The middle position of the transverse rod is provided with a bending sleeve that can be bent. , connected by inclined springs between the triangular frames at both ends.

The self-locking joint uses a servo motor to drive the worm to rotate, and the worm rotates to drive the turbine meshed with the worm to rotate.

The extension arm of the secondary mirror is installed in the fairing in a folded state before launching, and the installation structure in the fairing provides a binding force to the extension arm of the secondary mirror.

The sub-reflector of the optical system is a parabolic thin-walled structure with a certain thickness.

Among the conformal structures:

After the sub-reflector and the communication antenna are butt-connected, the radius of curvature of the communication antenna is smaller than that of the sub-reflector, and six fixed supports are evenly arranged in the gap formed between the non-connected positions of the two, and the fixed supports are trapezoidal structure, and its two sides have radians matched with the corresponding connecting surfaces.

The fixed support frame is connected with the communication antenna feed support structure, and the communication antenna feed support structure is fixedly connected with the communication antenna feed by means of triangular support, so that the communication antenna feed is located at the focus of the communication antenna.

The center of the outer surface of the secondary mirror is provided with a secondary mirror fixing structure of the optical system, which is used for connecting with the extension arm of the secondary mirror.

The fixing structure of the sub-reflector of the optical system is a ring-shaped or polygonal boss.

The sub-reflector of the optical system and the communication antenna are made of carbon fiber composite materials, and the thin-walled bottom surface of the sub-reflector of the optical system is coated with a layer of aluminum film.

The secondary reflector adopts the same aperture size as the communication antenna.

Among them the side hood deployment system:

The bottom folding rod mainly includes the upper section of the folding rod, the lower section of the folding rod and the fixed section of the folding rod, and the self-locking joint driven by the motor. After they are together, fold them vertically to the inside of the fixed section of the folding rod.

The top telescopic collar support rod structure includes a fixed collar, a telescopic collar, a lead screw guide, a ball sleeve, a support rod, a support arm, a hinge, a support rod fixed end, and a guide rail fixed triangle. The fixed collar is fixedly connected to the secondary mirror extension. At the end of the arm, the lead screw guide is longitudinally connected to the fixed collar, the telescopic collar can be slidably connected to the lead screw guide so that it can slide along the lead screw guide, and the hinge protrusion is arranged on the fixed return. It is connected with a support rod, the support rod is connected with the side hood, the middle part of each support rod is hinged with one end of a support arm, the other end of the support arm is hinged with the telescopic collar, and the length of the support arm is greater than the connecting position of the support rod The length to the hinge but less than the length of the support rod.

The bottom end of the screw guide is connected with the triangular guide fixed triangle.

The screw guide is composed of a screw, a screw mounting seat, and a stepping motor. The top of the screw mounting seat is fixedly connected with the fixing collar, and the bottom is fixed with the guide rail fixing triangle. The stepping motor is installed in the screw mounting seat and drives the screw. The screw rotates in the lead screw mount.

The end of the support rod is provided with a degree of bending for connecting with the side visor.

The side sunshade adopts flexible solar cells, and the solar cells are used to supply power to the power supply system of the satellite.

One of the bottom hood deployment systems:

The bottom hood extension mechanism is arranged on the outer side of the main mirror base, and includes a ring-shaped guide rail with a gear ring, a guide rail slider set on the ring gear ring guide rail, a motor-driven self-locking joint, and a bottom part connected to the guide rail slider. Hood extension arm.

The extending arm of the bottom light shield has an empty groove structure, and aluminized polyimide films are stacked in the groove.

The bottom hood is made of aluminized polyimide film or flexible solar cells.

The bottom shade is received in a slot on the side of the extension arm of the bottom shade.

A fixed hood is arranged inside the base of the main mirror.

The base of the main mirror is provided with a plurality of fixing brackets pointing to the center, and the fixing brackets are all fixedly connected with the spout of the propellant tank of the propulsion system.

The self-locking joint uses a servo motor to drive the worm to rotate, and the worm rotates to drive the turbine meshed with the worm to rotate.

Other features and advantages of the present invention will be set forth in the description which follows, and in part will be apparent from the description, or may be learned by practice of the invention.

The technical solutions of the present invention will be further described in detail below through the accompanying drawings and embodiments.

Description of drawings

Figure 1 is a schematic diagram of the use state of the GEO high-resolution reflective optical imaging satellite.

FIG. 2 is a schematic diagram of the use state of the GEO high-resolution reflective optical imaging satellite without the light shield.

Figure 3 is a schematic diagram of the retracted state of the GEO high-resolution reflective optical imaging satellite.

FIG. 4 is a schematic diagram of the folded state of the main mirror.

FIG. 5 is a schematic diagram of an open state of the main mirror.

FIG. 6 is a structural diagram of the conformal structure of the sub-reflector and the communication antenna.

FIG. 7 is a cross-sectional structural view of the conformal structure of the sub-reflector and the communication antenna.

FIG. 8 is a bottom view structural diagram of the conformal structure of the sub-reflector and the communication antenna.

FIG. 9 is a schematic diagram of the structural unit of the extension arm of the secondary mirror.

FIG. 10 is a schematic diagram of the structural unit of the extension arm of the secondary mirror.

FIG. 11 is a schematic diagram of the structural unit of the extension arm of the secondary mirror.

Figure 12 is a schematic diagram of the assembly of each sub-system of the satellite.

Figure 13 is a schematic diagram of the connection between the satellite propellant storage tank and the base of the primary mirror.

FIG. 14 is a schematic diagram of the retracted state of the extension mechanism of the light shield.

FIG. 15 is a schematic diagram of the extended state of the hood extending mechanism.

Figure 16 is a schematic diagram of the retracted state of the top telescopic collar support rod.

FIG. 17 is a schematic diagram of the open state of the top telescopic collar support rod.

FIG. 18 is a schematic diagram of the structure of the screw guide rail.

FIG. 19 is a schematic diagram of the retracted state of the bottom light shield extension mechanism.

FIG. 20 is a schematic view of the open state of the bottom light shield extension mechanism.

Figure 21 is a schematic diagram of the structure of the main mirror base.

FIG. 22 is a schematic structural diagram of a secondary mirror of an optical system.

In the picture:

1. Main reflector; 2. Conformal structure; 3. Optical camera; 4. Extending arm of secondary mirror; 5. Side hood; 6. Bottom folding rod; 7. Top telescopic collar support rod structure; 8. Bottom shading Cover; 9. Bottom hood stretching mechanism; 10. Satellite subsystem; 11. Optical main mirror film; 12. Main mirror support frame; 13. Mirror film traction frame; 14. Main mirror base; 15. Self-locking joint ; 14A, circumscribed ring; 14B, main beam;

21. Optical system sub-reflector; 22. Communication antenna; 23. Communication antenna feed; 24. Communication antenna feed support structure; 25. Fixed support frame; 26. Optical system sub-reflector fixed structure;

41. Frame unit; 41A, longitudinal rod; 41B, transverse rod; 41C, torsion spring; 41D, ball hinge; 41E, spring;

61. Upper section of folding rod; 62. Lower section of folding rod; 63. Fixed section of folding rod; 64. Self-locking joint; 65. Self-locking joint;

71, fixed collar; 72, telescopic collar; 73, lead screw guide; 731, lead screw; 732, guide rail mounting seat; 733, stepper motor; 74, ball sleeve; 75, support rod; 76, support arm ;77, hinge; 78, fixed end of support rod; 79, fixed triangle of guide rail;

81. The hood on the periphery of the main mirror base;

91. Ring-shaped guide rail with gear ring; 92. Guide rail slider; 93. Self-locking joint; 94. Bottom hood extension arm;

101, the nozzle; 102, the propellant tank of the propulsion system; 103, other sub-systems; 104, the fixed bracket; 105, the hexagonal ring; 106, the fixed structure.

Detailed ways

In order to make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below with reference to the specific embodiments of the present invention and the corresponding drawings. Obviously, the described embodiments are only some, but not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

The GEO high-resolution reflective optical imaging satellite of the present invention, as shown in Figures 1 and 2, consists of a satellite optical system main mirror 1, an optical system sub-mirror 21 and a conformal structure 2 of a communication antenna 22, an optical camera 3, The secondary mirror extension arm 4 , the side shade 5 , the bottom folding rod 6 , the top telescopic collar support rod structure 7 , the bottom shade 8 , the bottom shade extension mechanism 9 and the satellite subsystem 10 are composed.

Among them, the primary mirror 1, the secondary mirror extending arm 4 and the secondary mirror 21 form a primary and secondary mirror telescopic system. The primary mirror 1 can be stretched and opened in the circumferential direction, and the secondary mirror stretching arm 4 can be stretched in the length direction. The mirror 21 is installed at the end of the extension arm 4 of the secondary mirror, the extension arm 4 of the secondary mirror is connected with the center of the primary mirror 1, and the primary mirror 1 is opened to form a concave spherical surface.

The bottom hood 8 and the bottom hood stretching mechanism 9 constitute a bottom hood unfolding system, and are arranged outside the main reflector 1 of the primary and secondary mirror extension system. The bottom light-shielding cover extending mechanism 9 can open the bottom light-shielding cover 8 in the circumferential direction in a folding manner to cover the main reflector.

The conformal structure 2 is arranged at the end of the extension arm 4 of the secondary mirror, and concentrically connects the secondary mirror 21 and the communication antenna 22 , wherein the communication antenna 22 is located outside the secondary mirror 21 .

The optical camera 3 is installed in the secondary mirror extension arm 4 of the primary and secondary mirror extension system.

As shown in Figure 3, in order to reduce the volume of the satellite, the GEO high-resolution reflective optical imaging satellite is in a folded and compressed state before launch. The designed GEO high-resolution reflective optical imaging satellite can realize the ultra-high resolution of 2m above the ground. The primary mirror 1 of the optical system has a diameter of 12m and a radius of curvature of 144m; the secondary mirror of the optical system has a diameter of 4.2m and a radius of curvature of 143.9m. m; the distance between the primary mirror and the secondary mirror is 46.8m; the distance between the focal point and the vertex of the primary mirror is 8.02m, these parameters can be changed according to the choice of resolution.

About the main reflector and the secondary reflector telescopic system:

The satellite is in a compressed state before launch, as shown in Figure 4, the main mirror 1 of the satellite optical system is folded. The satellite optical main mirror 1 adopts a film unfolding design, and 24 fan-shaped optical main mirror films 11 are supported by 12 main mirror support frames 12 and 12 mirror film traction frames 13, and 12 main mirror support frames 12 and 12 The mirror film traction frame 13 is a curved rib plate with a certain curvature, and is connected with the main mirror base 14 by means of 24 self-locking joints 15 driven by motors. The self-locking joint uses the servo motor to drive the worm to rotate, and the worm rotates to drive the turbine that meshes with the worm to rotate. The self-locking function of the joint is realized by the design that the lead angle of the worm is smaller than the friction angle of the meshing contact. After the satellite is launched into orbit, 24 motors installed at the bottom of the main mirror support frame 12 drive 12 main mirror support frames 12 and 12 mirror film traction frames 13 to move around the motor-driven self-locking joints 15 to move the optical main mirror. When the thin 11 is unfolded, the main reflector 11 is fully unfolded and the motor stops working. After unfolding, the structure of the optical main mirror 1 is shown in FIG. 5 .

The main mirror base 14 is made of equilateral 12-sided rings as a force-bearing mechanism, and the 24 skeletons of the main mirror are gathered and folded in the middle to leave a predetermined space. Twelve main mirror support frames 12 protrude from the apex of the 12-sided ring of the main mirror base 14, and 12 mirror film traction frames 13 extend from the midpoint of each side length of the 12-sided ring. The 24 frames and the main The mirror base 14 together constitute the main structure of the main mirror 1 , and the main mirror 1 is folded and unfolded through the self-lockable joint 15 driven by the motor. In addition, a circular hole is designed at the intersection of the 12 main mirror support frames 12 and the 12 mirror film traction frames 13 to reserve space for the piping arrangement of the rail control sub-system. The main mirror supporting frame 12 and the mirror film pulling frame 13 are fixedly connected with the optical main mirror film 11 . The material of the optical main reflector film 11 is a piezoelectric material lens made of polyvinylidene fluoride, which changes shape rapidly under the scanning of a computer-controlled electron gun. This lightweight thin film structure, after being folded and launched and unfolded on-orbit, can control the mirror surface forming error by an electron gun to be no more than 2.5×10 ^-5 mm, and the density of the piezoelectric material polyvinylidene fluoride used is no more than 1kg/m. To a large extent, it meets the design requirements of the satellite primary mirror.

The sub-reflector structure consists of a sub-reflector 21 and a sub-reflector fixing structure 22 of the optical system, as shown in FIG. 21 . The sub-reflector 21 of the optical system is a parabolic thin-walled structure with a certain thickness. According to the design parameters of the sub-reflector, it can be known that the curvature radius of the curved surface is 143.9m. The secondary mirror 21 is fixedly connected to the secondary mirror fixing structure 22 of the optical system. The fixing structure 22 of the secondary mirror of the optical system is a 12-sided ring structure. At the same time, the thin-walled bottom surface of the sub-reflector 21 of the optical system is coated with an aluminum film to reflect light.

After the GEO high-resolution optical satellite is launched into orbit, the distance between the primary mirror 1 of the optical system and the secondary mirror 21 of the optical system needs to reach several tens of meters to meet the imaging requirements of the satellite's optical system with a resolution of 2 m. However, a satellite at this height cannot be launched into orbit by a rocket. Therefore, a foldable and unfolded secondary mirror extension arm 4 needs to be added between the optical system primary mirror 1 and the optical system secondary mirror 21 to meet the satellite's on-orbit work. Require. The extension arm of the secondary mirror is installed in the fairing in a folded state before launching, and the mounting structure in the fairing constrains the extension arm of the secondary mirror (for example, set an openable lock at both ends of the extension arm of the secondary mirror in the folded state). Connecting rod, the locking connecting rod can be opened by motor control), so that it does not unfold. After the satellite flies away from the fairing, the binding force is unlocked and disappears. section expands.

As shown in FIG. 9 , the secondary mirror extension arm 4 is composed of a plurality of frame units 41 . The frame unit is composed of longitudinal rods 41A, transverse rods 41B, bending sleeves 41C, ball joints 41D, springs 41E and other components. The three thin-walled strip-shaped longitudinal rods 41A are first fixed to form a rigid triangular plane to achieve good support stability, and at the same time use less material and lighter structure than the quadrilateral structure; the three transverse rods 41A are connected to the rigid triangle. The planes are connected by ball joints 41D to form a rectangle, and springs 41E are fixed at each diagonal corner of the rectangle, and at the midpoints of the transverse rods are connected by curved sleeves 41C.

As shown in FIG. 10 , before the satellite is launched into orbit, the frame unit 41 is in a compressed state. The bar 41B is folded in half towards the center of mass of the rigid triangular plane formed by the longitudinal bar 41A through the middle high-rigidity torsion spring 41C. The high-rigidity torsion spring 41C deforms and stores elastic potential energy. The spring 41E installed at the diagonal corners of the rectangular plane formed by the hinged longitudinal rod 41A is compressed (the spring 41E is set to have no elastic potential energy when the transverse rod 41B is in a straight line, that is, the spring 41E does not have elastic force at this time); when the satellite is in orbit During operation, the restraint force disappears, and the elastic potential energy stored by the high-rigidity torsion spring 41C and the compression spring 41E is converted into kinetic energy, so that the entire secondary mirror extension arm 4 is opened, as shown in FIG. 11 . A plurality of frame units 41 share a rigid triangle to form the secondary mirror extending arm 4 .

The present invention has the following characteristics:

1. The optical path design of the double-mirror optical imaging system realizes that the primary reflector and the secondary reflector are located on the same side of the focal point of the primary reflector, and the object and image are located on both sides of the secondary reflector, reducing the actual length of the optical path.

2. Parameter design of the primary and secondary mirrors of the optical system with a resolution of 2 m in the geostationary orbit.

3. The folding mechanism design of the extension arm of the secondary mirror of the optical system with a resolution of 2m in the geostationary orbit.

4. The foldable and unfoldable film main reflector of GEO optical imaging satellite is composed of a fan-shaped optical main reflector film, a main mirror support frame, a mirror film traction frame, a main mirror base, and a motor-driven self-locking joint.

5. The main mirror support frame and the mirror film traction frame are curved rib plates with a certain curvature.

6. The main mirror of the GEO high-resolution optical satellite is folded before entering orbit, and unfolded after entering orbit.

7. Use the motor to drive the main mirror support frame and the mirror film traction frame to fold and unfold the film-type main mirror through the rotation of the self-locking joint driven by the motor.

8. The film material of the optical main reflector is a piezoelectric material lens made of polyvinylidene fluoride, and the mirror surface forming error is controlled by an electron gun.

9. The main mirror base, main mirror support frame and mirror film traction frame are made of carbon fiber material.

Effects of the present invention

1. Using the reflective optical imaging system to achieve high-resolution imaging of 2m stationary orbit, and there is no chromatic aberration;

2. The actual length of the optical path is reduced by placing the primary reflector and the secondary reflector on the same side of the focal point of the primary reflector;

3. The object and the image are located on both sides of the secondary mirror to reduce the difficulty of the manufacturing process;

5. The foldable and unfoldable film main reflector of the GEO optical imaging satellite is designed. The film is used to support the skeleton to pull the film so that it is in a folded state before the satellite enters orbit, which greatly compresses the overall size of the satellite. After folding, it can be directly put into in the satellite fairing;

6. The flexible film material used in the satellite is used as the material of the main reflector, which avoids the use of rigid materials, greatly reduces the structural weight of the entire satellite, and enables the satellite to enter orbit once under the existing conditions.

Regarding conformal structure 2:

When the satellite is in operation, the light reflected by the primary mirror 1 of the optical system is reflected twice by the secondary mirror 21 of the optical system. At the same time, in order to maintain the effective communication between the satellite in the GEO orbit and the ground, it is necessary to install a communication antenna on the satellite. In order to maximize the use of the existing structure of the satellite, reduce the number of satellite components. As shown in FIG. 6 , the conformal structure of the satellite sub-reflector and the communication antenna consists of the optical system sub-reflector 21 , the communication antenna 22 , the communication antenna feed 23 , the communication antenna feed support structure 24 , the fixed support frame 25 and the optical system The secondary mirror fixing structure 26 is composed.

FIG. 7 is a cross-sectional view of the conformal structure of the satellite sub-reflector and the communication antenna. The optical system sub-reflector 21 and the communication antenna 22 are two parabolic thin-walled structural members with the same diameter and different curvatures, and the bottoms of the two thin-walled structures overlap. , and is fixedly connected to the secondary mirror fixing structure 25 of the optical system. Generally, after the sub-reflector 21 and the communication antenna 22 are butt-connected, the radius of curvature of the communication antenna 22 is smaller than the radius of curvature of the sub-reflector 21, and six fixed supports are evenly arranged in the gap formed between the non-connected positions of the two. The frame 25, the fixed support frame 25 has a trapezoidal structure, and its two sides have arcs that match with the corresponding connecting surfaces. As shown in FIG. 8 , the optical system sub-reflector fixing support 25 is a 12-sided ring structure, which is fixedly connected to the optical system sub-reflector 21 , and the end face connected to the optical system sub-reflector 21 has the same characteristics as the optical system sub-reflector 21 . , so that it can better support the secondary mirror 21 of the optical system. The sub-reflector fixing support frame 25 of the optical system is fixedly connected with the sub-reflector extending arm 4 of the GEO optical satellite.

The optical system sub-reflector 21 and the communication antenna 22 are supported by a fixed support frame 25 to ensure the stability and strength of the structure. The fixing bracket 25 is a quadrilateral bracket with a certain thickness. The upper and lower sides have curves that fit the two structures and are respectively welded and fixed with the optical system sub-reflector 21 and the communication antenna 22. The left and right sides are vertical support beam structures. Six fixed supports 25 are distributed between the optical system sub-reflector 21 and the communication antenna 22 .

A rod-shaped communication antenna feed support structure 24 is fixed on every two fixed supports 25 and extends out from the focus of the communication antenna 22, and three communication antenna feed support structures 24 are connected to the communication antenna feed 23, so that the communication antenna The feed 23 is located at the focal point of the communication antenna 22, thereby enabling communication between the satellite and the ground. The optical system sub-reflector 21 and the communication antenna 22 are made of carbon fiber composite materials, and the thin-walled bottom surface of the optical system sub-reflector 21 is coated with an aluminum film to reflect light.

The optical system sub-mirror fixing structure 26 is an annular or polygonal boss.

The present invention has the following characteristics:

1. The conformal structure is composed of two parabolic thin-walled structural members with different curvatures of the sub-reflector of the optical system and the communication antenna, which undertakes the dual functions of reflecting light and communication.

2. The sub-reflector of the optical system is overlapped with the bottom of the two thin-walled structures of the communication antenna, and the middle is supported by a fixed structure to ensure the structural strength and stability.

3. Three rod-shaped communication antenna feed support structures are evenly extended from the edge of the thin-walled structure of the communication antenna to connect the communication antenna feed, so that the communication antenna feed is located at the focus of the communication antenna.

4. The sub-reflector of the optical system and the communication antenna use the same aperture size, and the volume of the satellite is reduced by stacking installation.

5. The thin-walled bottom surface of the sub-reflector of the optical system is coated with an aluminum film to reflect light.

In this embodiment, the conformal design of the sub-reflector of the optical system and the communication antenna is carried out. The satellite sub-reflector performs dual functions. When the GEO optical imaging satellite performs optical imaging on the ground, the concave surface of the satellite sub-reflector faces the ground as a parabolic antenna to communicate with the ground, while the convex surface of the sub-reflector serves as the satellite optical system. The light reflected by the primary mirror is concentrated for optical reflection. The existing structure of the satellite is used to the greatest extent, the satellite parts are reduced, and the volume of the optical satellite is compressed.

As shown in Figure 12, the satellite adopts the distributed design idea in the design of the sub-system. By using the main body of the satellite as the load platform, the satellite sub-system 10 is placed in it. The satellite sub-systems are: attitude control system, orbit control system. System, power supply and distribution system, thermal control system, data management system, camera and image processing system, communication system, these control systems can all be configured using the current satellite general system. As shown in FIG. 10 , the optical camera 3 , the propellant storage tank 102 of the propulsion system, and other subsystems 103 are fixed in the frame unit 41 of the secondary mirror extension arm 4 by the fixing structure 106 , and these frame units 41 have no bending sleeve 41C. The satellite does not fold before being in orbit. The structural shape and installation location of each sub-system can be specifically designed and installed according to the task. The nozzle 101 of the satellite propulsion subsystem is installed at the bottom of the satellite, and a hexagonal ring 105 is fixed by six fixing brackets 104 connected to the main mirror base 14. The fixation of the spout 101. The propellant storage tank 102 of the propulsion subsystem is connected to the nozzle 101 through a pipeline. The distributed design idea adopted in the design of the subsystem has innovated the traditional satellite platform-load design idea, broke the platform limitation of the traditional satellite, realized the flexible design of the subsystem-main frame, and reduced the overall requirements of the satellite. space and weight.

As shown in FIG. 13 , in order to ensure that the connection between the secondary mirror extension arm 4 and the main reflector 1 of the satellite optical system meets the load-bearing requirements, the rigid triangle of the building unit where the propellant storage tank 102 of the satellite propulsion subsystem is located is used as the benchmark, and the The outer ring 14A is connected to the bracket of the main mirror 1 of the extension satellite optical system, and the ring and the 24 skeletons of the main mirror are all in contact and fixed connection, which can achieve uniform bearing capacity. At the same time, three main beams 14B are extended from the 12-sided ring of the main mirror base 14 to be fixedly connected to the rigid triangular vertices on the circumscribed ring 14A to complete the connection of the entire secondary mirror extension arm 4 with the main mirror 1 of the satellite optical system. Bearing structure design.

About the side hood deployment system:

As shown in Figures 1 and 2, in order to eliminate the influence of stray light such as sunlight on the satellite optical system, it is necessary to install a light hood structure on the satellite. The hood system includes a side hood 5 and a bottom hood 8 . The side hood 5 is supported by the bottom folding rod 6 and the top telescopic collar support rod structure 7 . The function of the bottom folding rods 6 is to fix the lower ends of the side light shields 5, and there are six in total. When the satellite is deployed in orbit, the side visor 5 is stretched out in cooperation with the top telescopic collar support rod 7. As shown in FIG. 14, the bottom folding rod 6 is a segmented structure.

As shown in FIG. 15 , the bottom folding rod 6 mainly includes a folding rod upper section 61, a folding rod lower section 62, a folding rod fixing section 63, and a motor-driven self-locking joint 64 between the folding rod upper section 61 and the folding rod lower section 62, The motor-driven self-locking joint 65 between the upper section 61 of the folding rod and the fixed section 63 of the folding rod, the upper section 61 of the folding rod and the lower section 62 of the folding rod are folded and stored together and then folded vertically to the inside of the fixed section 63 of the folding rod. In order to ensure that the bottom folding rod 6 does not contact the main mirror 1 of the satellite optical system during folding, the folding rod fixing section 63 is first extended from the main mirror base 14 at a certain distance, and the folding rod fixing section 63 and the folding rod upper section 61 are driven by a motor. The self-locking joint 64 is connected with the self-locking joint 64, which adopts a reverse-folding structure. The fixed section 63 of the folding rod is vertically folded upward, and is connected with the lower section 62 of the folding rod by a motor-driven self-locking joint 65; the lower section 62 of the folding rod is vertically folded downward. The non-hinged end of the lower section 62 of the folding rod is fixedly connected with the side visor 5 .

As shown in Figure 16. When the satellite is deployed in orbit, the peripheral shading cloth is driven to expand to form a complete folding rod, thereby forming a support structure for pulling the shading cloth at the bottom of the satellite.

The function of the top telescopic collar support rod 7 is to cooperate with the bottom folding rod 6 to extend the side hood 5. As shown in Figure 17, the top telescopic collar support rod 7 has a structure including a fixed collar 71, a telescopic collar 72, and a lead screw. The guide rail 73 , the ball sleeve 74 , the support rod 75 , the support arm 76 , the hinge 77 , the support rod fixed end 78 , and the guide rail fixed triangle 79 . The fixed collar 71 is fixedly connected to the end of the extension arm 4 of the secondary mirror, the lead screw guide 73 is longitudinally connected with the fixed collar 71, and the telescopic collar 72 is slidably connected to the lead screw guide 73 so that it can follow the lead screw The guide rail 73 slides, and the hinges 77 are protruded and arranged on the fixed bracket 71. Each hinge 77 is connected with a support rod 75, the free end of the support rod 75 is connected with the side visor, and the middle of each support rod 75 is connected with a support arm 76 One end of the support arm 76 is hinged with the telescopic collar 72 , and the length of the support arm 76 is greater than the length between the joint position of the support rod 75 and the hinge 77 but less than the length of the support rod 75 . The fixing collar 71 is a circular ring, and is fixedly connected with the rigid triangle on the upper surface of the frame unit 41 at the uppermost end of the secondary mirror extension arm 4 . Three screw guide rails 73 are perpendicularly passed through the rigid triangular connection between the fixed collar 71 and the upper surface of the frame unit 41 , and the screw guide rails 73 are fixedly connected with the fixed collar 71 . The tops of the three screw guide rails 73 are at a certain distance from the fixing collar 71 and are fixedly connected with the optical system sub-reflector fixing structure 25 to support the optical system sub-reflector 2 .

As shown in FIG. 18 , the three screw guide rails 73 are composed of a screw 731 , a screw mounting seat 732 and a stepping motor 733 . The top of the screw mounting seat 732 is fixedly connected with the fixing collar 71 , and the bottom is fixed with the guide rail fixing triangle 79 , the stepping motor 733 is installed in the screw mounting seat and drives the screw 731 to rotate in the screw mounting seat. Six fixed ends 78 of support rods with a certain length are uniformly extended around the outer circumference of the fixed collar 71 , and the fixed ends 78 of the support rods are connected to the support rods 75 through spherical hinges 77 . The support rod 75 is formed by connecting two sections of elongated rods, and an obtuse angle is formed between the two rods. The top end of the support rod 75 is connected to the shading cloth. The telescopic collar 72 and the fixed collar 71 are both circular rings, and the telescopic collar 72 is moved on the lead screw guide rail 73 through the ball sleeve 74 . One end of the support arm 76 is hinged with the support rod 75, and the other part is hinged with the sliding sleeve. As shown in FIG. 15 , the top telescopic collar support rod 7 is in a folded state before the satellite enters the orbit, and the telescopic collar 72 moves down along the lead screw guide rail 73 at this time until the support arm 76 is parallel to the guide rail. After the satellite enters the orbit, the stepper motor connected with the guide rail of the lead screw structure rotates, and drives the ball sleeve 74 with the balls installed inside to move upward along the lead screw guide rail 73, and drives the support arm 76 and the support rod 75 to expand, so as to drive from the top On-orbit extension of the satellite shade cloth.

As shown in Figure 3, the side hood 5 of the GEO high-resolution optical imaging satellite is folded around the main mirror 1 of the folded optical system before the satellite is launched, and its folding is divided into radial compression folding and axial laminar folding . The radial folding is a zigzag fold, and its top and bottom are respectively connected with the top telescopic collar support rod structure 7 and the bottom folding rod 6. When the bottom folding rod 6 and the top telescopic collar support rod structure 7 are unfolded at the same time, the side visor 5 Expanding outward along the circumference, the zigzag folding angle becomes larger, and the total perimeter becomes larger, and the zigzag folding hood is fully unfolded to form a hexagon. When the secondary mirror extension arm 4 is unfolded, since the uppermost end of the secondary mirror extension arm is fixedly connected with the fixed collar 71 of the top telescopic collar support rod, when the secondary mirror extension arm 4 moves upward, the top telescopic collar support rod structure is driven. 7 moves upward, thereby driving the side shading cover 5 to stretch in the radial direction. After the rail is fully extended, as shown in Figure 1, a 6-sided giant shading structure will be formed. In order to make full use of this structure, the satellite uses flexible solar cells as the side shading cover 5 in the design, which not only shields the satellite optical system from light, but also serves as the satellite's energy system to supply power to the satellite.

The present invention has the following characteristics:

1. The self-expanding solar cell hood at the periphery of the GEO optical imaging satellite is supported and expanded by the top telescopic collar support rod structure and the partial folding rod structure.

2. The bottom folding rod is a reflex structure, and the top telescopic collar support rod is the traction mechanism of the shading cloth around the satellite. It folds and shrinks with the main skeleton of the satellite and extends on-orbit, so that the size of the shading structure around the satellite meets the fairing. requirements.

3. The flexible solar cells are used as the shading cloth around the satellite. While shading the satellite optical system, it also serves as the energy system of the satellite to supply power to the satellite, which reduces the structure of the satellite and reduces the overall weight of the satellite.

Effects of the present invention

The present invention designs a self-expanding solar cell hood for the periphery of a GEO optical imaging satellite. The hood is in a folded state before the satellite enters orbit. The hood can be unfolded by using the top telescopic collar support rod structure 7 and the bottom folding rod 6 , and uses foldable solar cells as the outer structure of the hood, which can be used as the energy system of the satellite to supply power to the satellite. The design of the folding and unfolding hood enables a GEO optical imaging satellite to achieve a single access rail.

About the bottom hood deployment system:

As shown in Figures 1 and 2, in order to eliminate the influence of stray light such as sunlight on the satellite optical system, it is necessary to install a hood structure on the satellite. The GEO optical imaging satellite hood includes a side hood 5 and a deployable hood 8 at the bottom of the satellite. The expandable hood 8 at the bottom of the GEO optical imaging satellite consists of two parts, namely the fixed hood inside the base of the main mirror and the expandable hood outside the base of the main mirror. The expandable hood outside the base of the main mirror is composed of a foldable hood cloth 81 and a bottom hood extension mechanism 9 .

In addition to the need for shading on the side of the satellite, the bottom of the satellite also needs shading. The hood 81 on the periphery of the main mirror base is unfolded by the bottom hood stretching mechanism 9. As shown in FIG. 19, the bottom hood stretching mechanism 9 is driven by a ring-shaped guide rail 91 with a gear ring, a guide rail slider 92, and two motors. Self-locking joint 93 and two bottom hood extension arms 94 are formed. Before the satellite enters orbit, two annular guide rail sliders 92, two motor-driven self-locking joints 93, and two bottom hood extension arms 94 are juxtaposed together, the bottom hood extension mechanism 9 is in a compressed state, and the bottom hood is stretched The arm 94 is rotated into a vertical state about a self-locking joint 93 driven by a motor. The bottom hood extending arm 94 has an empty slot structure, and aluminized polyimide films are stacked in the slot. When the satellite enters orbit, as shown in FIG. 20 , the bottom hood extending arm 94 is a self-locking joint driven by a motor. 93 is rotated into a horizontal state, the ring guide 91 with a gear ring is fixed, a gear is installed in the guide slider 92 and the gear meshes with the ring gear of the ring guide, the motor mounted on the guide slider drives the gear along the ring guide with the ring gear 91 Circular movement, the bottom light shield extension arm 94 is fixed on the annular guide rail slider 92 and moves with the movement of the annular guide rail slider 92, so that the two bottom light shield extension arms 94 are separated, so as to separate the aluminum-plated aluminum alloys stacked in the folding rod. The polyimide film is stretched, and the aluminized polyimide film is inlaid with a spider-like wire mesh. Before entering the rail, the wire mesh and the aluminized polyimide film are manually folded in the empty space of the extension arm 94 of the bottom hood. In the slot structure, the wire mesh is gradually expanded with the expansion of the aluminized polyimide film after entering the orbit to support the entire annular hood structure. As shown in Figure 20, a complete annular shape is formed at the bottom of the satellite. hood structure.

The self-locking joint uses the servo motor to drive the worm to rotate, and the worm rotates to drive the turbine that meshes with the worm to rotate. The self-locking function of the joint is realized by the design that the lead angle of the worm is smaller than the friction angle of the meshing contact.

As shown in Figure 21, the structure within the 12-sided ring of the main mirror base 14 does not change during the entire launch process. Therefore, in the initial structural design of the satellite, aluminized polyimide film (PI) is directly used as the shading cloth , wrap the satellite structure inside the main mirror base 14 side ring, and use the main mirror base 14 side ring and the 6 fixing brackets 104 of the nozzle fixing bracket to pull, and arrange the nozzle outside the hood.

The present invention has the following characteristics:

1. The expandable hood at the bottom of the GEO optical imaging satellite consists of two parts: the fixed hood inside the main mirror base and the expandable hood outside the main mirror base.

2. The expandable hood outside the base of the main mirror is composed of a bottom hood stretching mechanism and a foldable shading cloth. The bottom hood stretching mechanism is in a folded state before the satellite is launched, and the foldable shading cloth is stacked in the inner hollow slot.

3. The material of the foldable shade cloth is aluminized polyimide film (PI)

4. The bottom hood stretching mechanism uses the motor to drive the annular guide slider to open the foldable shading cloth in a fan shape along the annular guide.

5. The fixed hood inside the base of the main mirror is fixed by the nozzle fixing bracket.

Effects of the present invention

The invention designs an expandable light hood at the bottom of the GEO optical imaging satellite, which overcomes the defect that the fixed structure of the traditional light hood cannot be folded, is suitable for shading the bottom of the foldable primary mirror of the GEO optical imaging satellite, and reduces the rectification occupied Cover the space, so that the GEO optical imaging satellite can be launched into orbit at one time under the existing conditions.

To sum up, those skilled in the art can easily understand that, on the premise that there is no conflict, the above advantageous manners can be freely combined and superimposed.

The above description is only an embodiment of the present invention, and is not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the scope of the claims of the present invention.

Claims (8)

1. The bottom light shield unfolding system for the optical imaging satellite is characterized by comprising a bottom light shield stretching mechanism (9) and a bottom light shield (8) arranged on the bottom light shield stretching mechanism, wherein the bottom light shield stretching mechanism (9) can open the bottom light shield (8) in the circumferential direction in a folding mode so as to shield a main reflector.

2. The optical imaging satellite bottom shade deployment system of claim 1,

the bottom light shield extension mechanism (9) is arranged on the outer side of the main mirror base (14) and comprises a toothed ring annular guide rail (91), a guide rail slide block (92) arranged on the toothed ring annular guide rail (91), a motor-driven self-locking joint (93) and a bottom light shield extension arm (94) connected to the guide rail slide block.

3. The optical imaging satellite bottom shade deployment system of claim 2,

the bottom hood extension arm (94) is hollow, and an aluminized polyimide film is stacked in the hollow.

4. The optical imaging satellite bottom shade deployment system of claim 1,

the bottom light shield adopts an aluminized polyimide film or a flexible solar cell.

5. The optical imaging satellite bottom shade deployment system of claim 2,

the bottom hood (8) is received in a slot in the side of the bottom hood extension arm (94).

6. The optical imaging satellite bottom shade deployment system of claim 2,

a fixed light shield is arranged in the main mirror base (14).

7. The optical imaging satellite bottom shade deployment system of claim 2,

a plurality of fixed supports (104) pointing to the center are arranged in the main mirror base (14), and the fixed supports (104) are fixedly connected with a nozzle (101) of a propellant tank of the propulsion system.

8. The optical imaging satellite bottom shade deployment system of claim 2,

the self-locking joint drives the worm to rotate by using the servo motor, and the worm rotates and drives the worm wheel meshed with the worm to rotate.

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