A high thermal stability temperature control structure for the main system of a space camera

Abstract

The present invention relates to the field of spacecraft thermal control technology, specifically providing a high-thermal-stability temperature control structure for a space camera main system, comprising: a first thermal insulation layer, a second thermal insulation layer, a third thermal insulation layer, and a truss. The first thermal insulation layer, which is coated on the inner wall of the space camera main system and has a high solar spectrum absorptivity and a high infrared spectrum emissivity, is coated on the outer wall of the space camera main system and has a low solar spectrum absorptivity and a low infrared spectrum emissivity. A truss is also installed on the outer circumference of the space camera main system, and a third thermal insulation layer, which has a low solar spectrum absorptivity and a high infrared spectrum emissivity, is disposed on the truss. The present invention utilizes a multi-stage thermal insulation structure to improve the camera main system's ability to suppress the influence of the external thermal environment, effectively reducing the impact of external heat flux changes on the temperature stability of the camera main system.

Description

Technical Field

[0001] The present invention belongs to the technical field of spacecraft thermal control, and in particular relates to a high thermal stability temperature control structure for a main system of a space camera. Background Art

[0002] The main system structure of a space camera supports the camera's optical components. Deformation of this structure can directly cause positional shifts in these components, degrading image quality. Initially, during the satellite's orbital period, the camera's focusing mechanism compensates for any misalignment caused by main system deformation. Subsequently, during the camera's on-orbit lifespan, changes in the external thermal environment are the primary factor causing structural deformation. With the exception of a few space cameras whose orbital thermal environment remains relatively stable, most space cameras orbiting celestial bodies experience thermal changes primarily due to variations in direct stellar heat flux, infrared heat flux from celestial bodies, and reflected heat flux from celestial bodies. Due to the influence of celestial bodies, the orbit periodically transitions between sunlit and shadowed regions, causing dramatic variations in the camera's external thermal flux, with variations in direct stellar heat flux having the greatest impact. As space cameras advance toward higher resolution, longer focal lengths, and larger apertures, structural deformation caused by even small temperature changes in the main system structure can significantly degrade image quality, placing high demands on the thermal stability of the main system structure. Space cameras are mounted on satellite platforms, completely exposed to the exterior of the satellite's payload bay and directly affected by external heat fluxes. In order to ensure the thermal stability of the main system structure, a more efficient suppression design is needed to suppress the influence of external heat flow caused by orbital period changes.

[0003] Currently, thermal stability design for the camera's main system structure primarily involves coating the exterior of the main system components with a multi-layer thermal insulation assembly. The outermost layer of the multi-layer insulation features low solar absorptivity and high infrared emissivity. This reduces the maximum temperature of the multi-layer surface when exposed to direct solar radiation, minimizing the impact of high-temperature heat flux on the camera. Compensatory heating maintains the camera's operating temperature during periods of low solar radiation, minimizing temperature fluctuations. When low-orbit satellites are designed for long-term yaw-towards-the-Sun (Yao-Zhi) in the sunlit zone due to energy requirements, or when high-orbit satellites are exposed to long-term sunlight, the camera is exposed to sunlight for extended periods. The temperature of the multi-layer outer surface remains above 60°C, causing the camera's main system structure to heat up. When the temperature exceeds the closed-loop temperature control target for the compensated heating, the temperature of the camera's main system fluctuates periodically with the satellite's orbit, affecting image quality. Beyond a certain number of layers, increasing the number of layers significantly reduces the insulation effect. Furthermore, the solar absorptivity of the multi-layer surface film degrades with age, with a greater increase at the end of its lifespan compared to the beginning. Currently, methods such as increasing the number of layers of multi-layer masks and changing the solar absorption rate of multi-layer masks have limited effect on suppressing the high temperature effects of long-term direct solar heat flux on the outside of the camera, making it difficult to ensure the thermal stability requirements of the camera's main system structure. The impact of direct solar heat flux is particularly evident on large-size, long-focal-length cameras. Summary of the Invention

[0004] In view of this, the present invention aims to provide a high thermal stability temperature control structure for the main system of a space camera. By designing a truss structure on the circumferential outside of the camera main system structure, covering it with a thermal insulation layer, and forming a multi-level radiation insulation structure together with the thermal insulation layer of the camera main system structure itself, the thermal insulation ability of the camera and the external thermal environment is greatly improved, the impact of external heat flow changes on the camera temperature is reduced, the thermal stability of the camera main system structure is ensured, and thus the camera imaging performance is ensured.

[0005] To achieve the above object, the technical solution created by the present invention is implemented as follows:

[0006] The present invention provides a high thermal stability temperature control structure for a space camera main system, comprising:

[0007] A first thermal insulation layer covering the inner wall of the space camera main system, wherein the outer surface of the first thermal insulation layer has an absorptivity greater than or equal to 0.82 in the solar spectrum and an emissivity greater than or equal to 0.7 in the infrared spectrum;

[0008] A second thermal insulation layer covering the outer wall of the space camera main system, wherein the outer surface of the second thermal insulation layer has an absorptivity of less than or equal to 0.2 in the solar spectrum and an emissivity of less than or equal to 0.2 in the infrared spectrum;

[0009] A truss installed on the outer side of the space camera main system, with a third thermal insulation layer installed on the truss. The outer surface of the third thermal insulation layer has a solar spectrum absorptivity of less than or equal to 0.6, and an infrared spectrum emissivity of greater than or equal to 0.59. The inner surface of the third thermal insulation layer facing the space camera main system has a solar spectrum absorptivity of less than or equal to 0.2, and an infrared spectrum emissivity of less than or equal to 0.2.

[0010] There is a gap between the third thermal insulation layer and the second thermal insulation layer.

[0011] Preferably, the first heat insulation layer includes at least one layer of polyimide black film.

[0012] Preferably, the second heat-insulating layer includes at least one layer of aluminum-plated polyimide film.

[0013] Preferably, the trusses are made of thermally insulating material.

[0014] Preferably, the outer surface of the third thermal insulation layer is an F46 thin film silver-plated secondary surface mirror or a single-sided aluminum-plated polyimide secondary surface mirror, and the inner surface of the third thermal insulation layer is an aluminum-plated polyimide film.

[0015] Preferably, the gap size between the third thermal insulation layer and the second thermal insulation layer is 100 mm-300 mm, inclusive.

[0016] Preferably, a heat dissipation area is provided on the outer wall of the space camera main system, and a third heat insulation layer is not provided at the position corresponding to the heat dissipation area on the truss, so as to radiate heat from the space camera main system to the outside.

[0017] Preferably, the space camera main system is provided with a compensation heating unit to perform closed-loop temperature control on the space camera main system in partitions.

[0018] Preferably, a baffle is provided at the position of the top end surface opening of the space camera main system and the truss, and the baffle blocks a part of the top end surface opening of the space camera main system and the truss, and the blocked area of ​​the baffle is the entrance position of the direct heat flux of the in-orbit star of the space camera main system.

[0019] Preferably, it also includes: an active driving device for the baffle, which calculates the entrance position of the direct heat flow of the on-orbit star in real time according to the space attitude and orbit parameters of the space camera main system, and drives the baffle to move to the entrance position of the direct heat flow of the on-orbit star.

[0020] Compared with the prior art, the present invention can achieve the following beneficial effects:

[0021] The present invention not only designs thermal insulation structures on the inner and outer walls of the space camera main system, but also designs a truss structure in the circumference of the space camera main system, and installs a thermal insulation layer on the truss to form a multi-stage thermal insulation system, and innovatively designs the spectral characteristics of the three-layer thermal insulation structure based on temperature control requirements. The thermal insulation layer of the inner wall is designed to have a high solar spectrum absorptivity and a high infrared spectrum emissivity to meet the stray light elimination requirements of the camera optical system; the thermal insulation layer of the outer wall is designed to have a low solar spectrum absorptivity and a low infrared spectrum emissivity, which not only isolates external heat energy from entering the interior of the space camera main system, but also reduces the outward conduction of internal heat energy of the space camera main system, thereby maintaining the thermal stability of the space camera main system as much as possible; the thermal insulation layer on the truss is designed to have a low solar spectrum absorptivity and a high infrared spectrum emissivity, which not only isolates external heat energy from entering the gap between the space camera main system and the truss, but also improves the efficiency of heat energy conduction. By rationally selecting the material properties of the multi-layer mask, the radiation heat exchange between the multiple insulation layers is reduced, the ability of the insulation system to suppress the influence of the external thermal environment is greatly improved, constant temperature control is achieved, and the influence of sudden changes in the external thermal environment on the main system of the space camera is avoided. The design of the present invention has both heat dissipation and heat preservation capabilities. Compared with traditional designs that only have insulation capabilities, the design of the present invention has higher thermal stability and effectively reduces the influence of external heat flow changes on the camera imaging effect.

[0022] In order to prevent the direct heat flux from the on-orbit star from entering through the gaps in the insulation layer and irradiating the insulation layer on the outer wall of the space camera main system, causing the temperature of the irradiated area of ​​the insulation layer on the outer wall to rise rapidly and cause the insulation layer to burn, the present invention also provides a baffle at the position of the end face opening to block the entrance position of the direct heat flux from the star, thereby preventing the direct heat flux from irradiating the insulation layer on the outer wall of the system. The baffle position can be adjusted according to the camera attitude and satellite orbit parameters to achieve tracking of the entrance position of the direct heat flux from the star. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which constitute part of the present invention, are intended to provide a further understanding of the present invention. The exemplary embodiments of the present invention and their descriptions are intended to explain the present invention and do not constitute an undue limitation of the present invention. In the accompanying drawings:

[0024] Figure 1 2. It is a schematic diagram of a high thermal stability temperature control structure of a space camera main system not covered with a third thermal insulation layer according to an embodiment of the present invention;

[0025] Figure 2 2. It is a schematic diagram of a high thermal stability temperature control structure of a space camera main system covered with a third thermal insulation layer according to an embodiment of the present invention;

[0026] Figure 3 The figure is a schematic diagram of a high thermal stability temperature control structure of a space camera main system provided with a baffle according to an embodiment of the present invention.

[0027] Reference numerals include:

[0028] Space camera main system 1, satellite platform 2, first thermal insulation layer 3, second thermal insulation layer 4, truss 5, third thermal insulation layer 6, heat dissipation area 7, and baffle 8. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and do not constitute a limitation to the present invention. Similar elements in different embodiments use associated similar element numbers. In the following embodiments, many detailed descriptions are intended to enable the present invention to be better understood. However, those skilled in the art can easily recognize that some of the features can be omitted in different situations, or can be replaced by other elements, materials, or methods. In some cases, some operations related to the present invention are not shown or described in the specification. This is to avoid the core part of the present invention being overwhelmed by too much description. For those skilled in the art, it is not necessary to describe these related operations in detail. They can fully understand the related operations based on the description in the specification and the general technical knowledge in the art.

[0030] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments of the present invention can be combined with each other to form various implementation methods. At the same time, the steps or actions in the method description can also be interchanged or adjusted in a manner that is obvious to those skilled in the art. Therefore, the various orders in the description and the drawings are only for the purpose of clearly describing a certain embodiment and are not intended to be a required order, unless otherwise specified that a certain order must be followed.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0032] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "installed," "connected," and "connected" should be understood in a broad sense. For example, they can refer to fixed connections, detachable connections, or integral connections; they can refer to mechanical connections or electrical connections; they can refer to direct connections or indirect connections through an intermediate medium; and they can refer to internal connections between two components. Those skilled in the art can understand the specific meanings of the above terms in the present invention based on specific circumstances.

[0033] The present invention will be described in detail below with reference to the accompanying drawings and in combination with embodiments.

[0034] See also Figure 1 and Figure 2In one embodiment of the present invention, a high thermal stability temperature control structure for a space camera main system is provided, which is mainly used to control the temperature and insulate the space camera main system 1. Since the space camera main system 1 is installed on the satellite platform 2 and is outside the satellite payload cabin, the space camera main system 1 will be affected by changes in the external thermal environment during on-orbit operation, resulting in a decrease in imaging quality. In order to reduce the impact of external heat flow changes on the temperature stability of the space camera main system 1, an embodiment of the present invention designs a high thermal stability temperature control structure for the space camera main system 1, which specifically includes: a first thermal insulation layer 3, a second thermal insulation layer 4, a truss 5 and a third thermal insulation layer 6, wherein the first thermal insulation layer 3 covers the inner wall of the space camera main system 1. The outer shell of the space camera main system 1 is mostly a cylindrical structure, and the optical imaging component is arranged inside the shell. Because the interior of the space camera main system 1 has high extinction requirements and requires minimal stray light suppression, the first thermal insulation layer 3 utilizes a film material with high solar spectrum absorptivity and high infrared spectrum emissivity. This film material absorbs a significant amount of stray light entering the optical system, reducing its impact on image contrast and clarity. High infrared spectrum emissivity helps dissipate internal camera heat outward as infrared radiation, achieving effective heat dissipation. Using this film material for the first thermal insulation layer 3 ensures smoother and more uniform temperature changes within the structure, reducing thermal stress and ensuring the stability of the space camera main system 1.

[0035] The first thermal insulation layer 3 can be made of at least one layer of polyimide black film, which has the high solar spectrum absorptivity and high infrared spectrum emissivity required by the design. Typically, based on actual needs, the inner wall of the space camera main system 1 can be covered with about 10 layers of thermal insulation material, but the outermost layer needs to be made of polyimide black film to achieve the effect of eliminating stray light. Except for the outermost layer of polyimide black film, the remaining layers can be designed with alternating layers of double-sided aluminum-coated polyester film and polyester mesh. Since the first thermal insulation layer 3 is located inside the camera optical path, it needs to be made of a material with high solar spectrum absorptivity to achieve stray light elimination. After testing and verification, the solar spectrum absorptivity of the first thermal insulation layer 3 must be greater than or equal to 0.82; the infrared spectrum emissivity of the first thermal insulation layer 3 must be greater than or equal to 0.7. In an embodiment of the present invention, the solar spectrum absorptivity of the first thermal insulation layer 3 is 0.92, and the infrared spectrum emissivity of the first thermal insulation layer 3 is 0.8.

[0036] The second thermal insulation layer 4 is disposed on the outer wall of the housing of the space camera main system 1. It is constructed from a film material with low solar absorptivity and low infrared emissivity. Typically, at least one layer of aluminum-coated polyimide film is used. Similarly, only the outermost layer of the second thermal insulation layer 4 needs to be aluminum-coated polyimide film. Besides the outermost layer of aluminum-coated polyimide film, the remaining layers can also be constructed from alternating layers of double-sided aluminum-coated polyester film and polyester mesh. Materials with low solar absorptivity reflect more sunlight, thereby reducing the amount of heat absorbed by the space camera main system 1 from the external environment. This design effectively reduces the temperature rise of the camera main system structure when the satellite enters a sunlit area, preventing a rapid rise in the camera's internal temperature due to excessive heat absorption, which could damage optical components and electronic equipment, affecting image quality and proper operation. The low infrared emissivity reduces the amount of heat radiated from the space camera main system 1 to the outside. When the satellite enters the shadow zone, the space camera main system 1 does not need to dissipate heat. On the contrary, the cold black space will reduce the temperature of the space camera main system 1. To avoid the temperature of the space camera main system 1 dropping suddenly due to the cold black space, the use of low infrared emissivity materials helps to maintain the heat inside the space camera main system 1 and prevent it from dissipating heat too quickly to the external cold black space, thereby maintaining a relatively stable internal temperature of the camera and reducing the impact of temperature fluctuations on camera performance. The second thermal insulation layer 4 not only reduces the temperature increase effect of external heat flow on the space camera main system 1 in the sunny area, but also suppresses the cooling effect of external cold currents on the space camera main system 1 in the shadow area, achieving stable temperature control. After testing and verification, the solar spectrum absorptivity of the second thermal insulation layer 4 must be less than or equal to 0.2, and the infrared spectrum emissivity of the second thermal insulation layer must be less than or equal to 0.2. In the embodiment of the present invention, the solar spectrum absorptivity of the second thermal insulation layer 4 is 0.1, and the infrared spectrum emissivity of the second thermal insulation layer is 0.1.

[0037] In order to prevent direct sunlight from affecting the service life of the second thermal insulation layer 4, which would affect the service life of the space camera main system 1, the embodiment of the present invention further provides a truss 5 on the circumferential outside of the space camera main system 1. The shape of the truss 5 is designed according to the shape of the outer shell of the space camera main system 1. When the outer shell of the space camera main system 1 is cylindrical, the diameter of the truss 5 is designed to be slightly larger than the outer shell diameter of the space camera main system 1, so that a heat dissipation gap is left between the truss 5 and the outer arm of the space camera main system 1. It should be noted that since the bottom of the space camera main system 1 is installed on the satellite platform 2, and the top needs to collect light, the truss 5 only needs to be designed on the circumferential outside of the space camera main system 1, and the top and bottom usually do not need to be designed with a truss 5.

[0038] To prevent heat exchange between the space camera main system 1 and the external environment through the truss 5, the truss 5 is preferably made of carbon fiber with low linear expansion and low thermal conductivity. The truss 5 is mounted to the outer wall of the space camera main system 1 via carbon fiber brackets. These brackets support the truss 5 and isolate heat conduction between the truss 5 and the space camera main system 1, minimizing the thermal impact of the low-temperature truss 5 on the space camera main system 1.

[0039] A third thermal insulation layer 6 is installed on the truss 5. The outer surface of the third thermal insulation layer 6 is designed with low solar spectrum absorptivity and high infrared spectrum emissivity, such as F46 thin film silver-coated secondary surface mirrors, single-sided aluminum-coated polyimide secondary surface mirrors, etc. Similarly, the outer surface of the third thermal insulation layer 6 only needs to be made of F46 thin film silver-coated secondary surface mirrors, single-sided aluminum-coated polyimide secondary surface mirrors, etc. The remaining layers can also be designed with alternating structural layers of double-sided aluminum-coated polyester film and polyester mesh. After testing and verification, the solar spectrum absorptivity of the outer surface of the third thermal insulation layer 6 must be less than or equal to 0.6, and the infrared spectrum emissivity of the outer surface of the third thermal insulation layer 6 must be greater than or equal to 0.59. In an embodiment of the present invention, the solar spectrum absorptivity of the outer surface of the third thermal insulation layer 6 is 0.5, and the infrared spectrum emissivity of the outer surface of the third thermal insulation layer 6 is 0.69. The inner surface of the third thermal insulation layer 6, facing the space camera main system 1, is designed with low solar spectrum absorptivity and low infrared spectrum emissivity, such as double-sided aluminum-coated polyimide film. Similarly, the inner surface of the third thermal insulation layer 6, facing the space camera main system 1, only needs to be made of double-sided aluminum-coated polyimide film for the outermost layer. Besides the outermost layer of double-sided aluminum-coated polyimide film, the remaining layers can also be constructed with alternating layers of double-sided aluminum-coated polyester film and polyester mesh. The outer surface of the third thermal insulation layer 6 reflects sunlight energy, preventing the camera from absorbing excessive heat from the external environment. It also efficiently dissipates heat as infrared radiation, preventing excessive temperatures from affecting camera performance and lifespan. The inner surface of the third thermal insulation layer 6 is designed with low solar spectrum absorptivity and low infrared spectrum emissivity, primarily to prevent the small amount of sunlight that penetrates from the outside from being absorbed and converted into heat within the camera, further reducing heat accumulation within the camera and preventing excessive internal temperatures. Furthermore, it reduces the amount of heat transmitted from the third thermal insulation layer 6 to the space camera main system 1. After testing and verification, the inner surface of the third thermal insulation layer 6 must have a solar spectrum absorptivity of less than or equal to 0.2, and a infrared spectrum emissivity of less than or equal to 0.2. In the embodiment of the present invention, the inner surface of the third thermal insulation layer 6 has a solar spectrum absorptivity and an infrared spectrum emissivity of 0.1.

[0040] The present invention utilizes a first insulation layer 3, a second insulation layer 4, and a third insulation layer 6 to achieve multi-level thermal insulation. This significantly improves the temperature control structure's ability to suppress the effects of the external thermal environment and reduces the impact of external heat flux changes on the temperature stability of the space camera's main system 1. Furthermore, the selected materials must meet the design requirements of the camera's orbital space environment, such as protection against static electricity, ultraviolet radiation, space particle irradiation, and atomic oxygen.

[0041] Truss 5 is mounted on the outer wall of the space camera main system 1, resulting in a gap between the second insulation layer 4 and the third insulation layer 6. The size of this gap is determined based on a comprehensive consideration of the camera's structural and thermal design. An excessively large gap can result in poor mechanical properties for truss 5, and external heat flux can directly affect the space camera main system 1 through the gap between truss 5 and the space camera main system 1, weakening the third insulation layer 6's ability to suppress external heat flux. An excessively small gap prevents the truss 5 from dissipating heat during exposure. Extensive experimental testing and demonstration have determined that the gap between the second insulation layer 4 and the third insulation layer 6 is preferably between 100 mm and 300 mm, inclusive.

[0042] As an optional embodiment, under normal circumstances, an independent heat dissipation area 7 is provided on the outer wall of the space camera main system 1 to ensure rapid heat dissipation during the illumination process. During on-orbit operation, the heat dissipation area 7 is usually on the opposite side of the illuminated surface of the space camera main system 1, that is, on the side corresponding to the cold black space, so as to quickly dissipate the heat. In order to ensure that the radiation heat dissipation channel of the space camera main system 1 to the external cold black space is unobstructed and to reduce the obstruction of the heat dissipation area 7 by the third thermal insulation layer 6, the third thermal insulation layer 6 is not provided on the truss 5 at the position corresponding to the heat dissipation area 7, that is, an opening is reserved in this area and is not covered by the third thermal insulation layer 6. As for the size of the reserved opening, it is generally believed that each boundary of the radial projection of the reserved opening on the space camera main system 1 is larger than the heat dissipation area 7200mm.

[0043] As an optional embodiment, a compensating heating unit is installed on the space camera main system 1. This compensating heating unit comprises multiple partitioned modules. The heating modules are divided according to the principle of consistent external heat flow, and the heating capacity of each partitioned module can be independently controlled. Furthermore, each module uses active closed-loop temperature control to ensure that the space camera main system 1 maintains high thermal stability throughout its on-orbit lifespan.

[0044] As an optional embodiment, since there is a gap between the second thermal insulation layer 4 and the third thermal insulation layer 6, when the direct heat flux from the star is large and the incident angle of light is small, the direct light may enter the gap between the second thermal insulation layer 4 and the third thermal insulation layer 6 from the top end opening of the space camera main system 1 and the truss 5. Since the third thermal insulation layer 6 has a good shielding effect on the cold black space, the direct heat flux from the star directly hits the second thermal insulation layer 4, which will cause the temperature of the illuminated area of ​​the second thermal insulation layer 4 to rise rapidly, causing the second thermal insulation layer 4 to burn. Figure 3 As shown, the embodiment of the present invention further provides a baffle 8 at the position of the top end surface opening of the space camera main system 1 and the truss 5, and the baffle 8 blocks a portion of the top end surface opening of the space camera main system 1 and the truss 5. The baffle 8 is made of carbon fiber honeycomb panel, and the outer surface of the baffle 8 is sprayed with white paint with low solar spectrum absorption rate and high infrared spectrum emissivity, ensuring that the solar spectrum absorption rate is ≤0.35 and the infrared spectrum emissivity is ≥0.9. The top end surface opening is annular, and the direct heat flux from the star will only be incident from a portion of the annular area, so it is only necessary to design the baffle 8 as a baffle 8 that can block a portion of the annular area. The shielding area of ​​the baffle 8 is the entrance position of the direct heat flux from the in-orbit star of the space camera main system 1. Since the entrance position of the direct heat flow from the star in orbit is constantly changing during the on-orbit change process, the present invention designs the baffle 8 to be movable, such as installing the baffle 8 at the gap position of the top end face opening through a slide rail or other device, and designs an active driving device for the baffle 8. The active driving device calculates the entrance position of the direct heat flow from the star in orbit in real time according to the space attitude and orbit parameters of the space camera main system 1, and drives the baffle 8 to move to the entrance position of the direct heat flow from the star in orbit, thereby tracking the entrance position of the direct heat flow from the star and always blocking the direct heat flow from the star.

[0045] Compared with the traditional method of directly wrapping a single thermal insulation material on the outside of the space camera main system 1, the present invention can not only reduce the heat absorption when exposed, but also reduce the heat exchange when not exposed, so as to maintain the temperature stability inside the space camera main system 1 as much as possible, and avoid external heat flow causing sudden temperature changes of the space camera main system 1. The present invention adopts a multi-stage thermal insulation and temperature control design, and specially designs the optical properties of each insulation surface, thereby improving the temperature control structure's ability to suppress the influence of the external thermal environment, and effectively reducing the influence of external heat flow changes on the temperature stability of the space camera main system 1.

[0046] In short, the above description is only a preferred embodiment of this specification and is not intended to limit the scope of protection of this specification. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this specification shall be included in the scope of protection of this specification.

[0047] The systems, devices, modules, or units described in one or more of the above embodiments may be implemented by a computer chip or entity, or by a product having a certain function. A typical implementation device is a computer. Specifically, the computer may be, for example, a personal computer, a laptop computer, a cellular phone, a camera phone, a smartphone, a personal digital assistant, a media player, a navigation device, an email device, a game console, a tablet computer, a wearable device, or a combination of any of these devices.

[0048] It should also be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, commodity, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or includes elements inherent to such process, method, commodity, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, commodity, or apparatus that includes the element.

[0049] The various embodiments in this specification are described in a progressive manner. Similar parts between the various embodiments can be referred to in conjunction with each other. Each embodiment focuses on the differences between the other embodiments. In particular, the system embodiments are generally similar to the method embodiments, so the description is relatively simple. For relevant parts, refer to the description of the method embodiments.

Claims

1. A high thermal stability temperature control structure for a space camera main system, characterized in that: include: a first thermal insulation layer covering the inner wall of the space camera main system, wherein the outer surface of the first thermal insulation layer has a solar spectrum absorptivity greater than or equal to 0.82 and an infrared spectrum emissivity greater than or equal to 0.7; a second thermal insulation layer covering an outer wall of the space camera main system, wherein the outer surface of the second thermal insulation layer has an absorptivity of less than or equal to 0.2 in the solar spectrum and an emissivity of less than or equal to 0.2 in the infrared spectrum; A truss installed on the outer side of the space camera main system, wherein a third thermal insulation layer is installed on the truss, wherein the outer surface of the third thermal insulation layer has a solar spectrum absorptivity of less than or equal to 0.6 and an infrared spectrum emissivity of greater than or equal to 0.59, and the inner surface of the third thermal insulation layer facing the space camera main system has a solar spectrum absorptivity of less than or equal to 0.2 and an infrared spectrum emissivity of less than or equal to 0.2; There is a gap between the third heat insulation layer and the second heat insulation layer.

2. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: The first heat insulation layer includes at least one layer of polyimide black film.

3. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: The second heat-insulating layer includes at least one layer of aluminum-plated polyimide film.

4. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: The trusses are made of thermally insulating material.

5. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: The outer surface of the third thermal insulation layer is an F46 thin film silver-plated secondary surface mirror or a single-sided aluminum-plated polyimide secondary surface mirror, and the inner surface of the third thermal insulation layer is an aluminum-plated polyimide film.

6. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: The gap size between the third thermal insulation layer and the second thermal insulation layer is 100 mm-300 mm, inclusive.

7. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: A heat dissipation area is provided on the outer wall of the space camera main system, and the third heat insulation layer is not provided at the position corresponding to the heat dissipation area on the truss, which is used for the space camera main system to radiate heat to the outside.

8. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: The space camera main system is provided with a compensation heating unit, which performs closed-loop temperature control on the space camera main system in different zones.

9. The high thermal stability temperature control structure of the space camera main system according to claim 1, characterized in that: A baffle is provided at the position of the opening of the top end surface of the space camera main system and the truss, and the baffle blocks a part of the area of ​​the opening of the top end surface of the space camera main system and the truss. The blocked area of ​​the baffle is the entrance position of the direct heat flux of the in-orbit star of the space camera main system.

10. The high thermal stability temperature control structure of the space camera main system according to claim 9, characterized in that: Also includes: The active driving device of the baffle calculates the entrance position of the direct heat flow of the on-orbit star in real time according to the space attitude and orbit parameters of the space camera main system, and drives the baffle to move to the entrance position of the direct heat flow of the on-orbit star.

Images