A thermal design device for a stereo distribution focal plane assembly of a space camera

Abstract

The present application relates to the technical field of spacecraft thermal control, and specifically provides a kind of thermal design device of space camera stereo distribution focal plane assembly, comprising: frame and multiple sub focal planes, multiple sub focal planes are evenly attached to the side of frame by heat insulation pad;The inner surface of multiple sub focal planes is sequentially connected with detector heat pipe, and the outer surface of multiple sub focal planes is sequentially connected with imaging processing circuit heat pipe;Detector heat pipe and imaging processing circuit heat pipe are arranged in parallel on multiple sub focal planes;The hot end of detector heat pipe and the cold end of detector heat pipe, the hot end of imaging processing circuit heat pipe and the cold end of imaging processing circuit heat pipe are all in the same horizontal plane;Or the cold end of detector heat pipe is higher than the hot end of detector heat pipe, and the cold end of imaging processing circuit heat pipe is higher than the hot end of imaging processing circuit heat pipe.The present application guarantees that detector heat pipe and imaging processing circuit heat pipe can be normally started during ground test by the parallel arrangement of detector heat pipe and imaging processing circuit heat pipe.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft thermal control technology, and particularly relates to a thermal design device for a three-dimensional distributed focal plane assembly of a space camera. Background Technology

[0002] To achieve wide-coverage observations, space cameras typically employ focal plane assemblies composed of multiple detectors mechanically or optically stitched together. Detector dark current and noise are closely related to temperature, and temperature variations can cause thermal deformation of the focal plane substrate, leading to decreased stitching accuracy. Each detector and its imaging processing circuitry form a sub-focal plane. To ensure camera imaging performance, precise temperature control of the detectors and their imaging circuitry is crucial. As space cameras increasingly demand high-resolution observation capabilities, detector power density has increased accordingly. Detectors typically weigh only tens of grams and have relatively small heat capacities; therefore, rapid heat dissipation during long-term operation is a critical task in space camera thermal design. Current heat dissipation designs for detectors and imaging processing circuits generally utilize heat pipes with ultra-high thermal conductivity as the primary heat dissipation path, thermally connected to external heat sinks, which radiate heat into the cold black space to dissipate heat. With the increasing functionality of cameras, the number of camera electronics, focal plane assemblies, and other components has increased. To achieve optimal camera structure and the layout of individual components, the arrangement of sub-focal planes can no longer be entirely based on one-dimensional or two-dimensional spatial arrangement. For focal plane assemblies with a three-dimensional distribution of sub-focal planes, a separate heat dissipation channel design is required for each sub-focal plane. Furthermore, considering maintaining the focal plane storage temperature during camera downtime, a thermal compensation heating design is needed for each sub-focal plane. This complicates the overall thermal control system of the focal plane assembly, reduces camera reliability, and increases weight and cost. Multiple heat pipe arrangements can lead to difficulties in coordinating ground test startup, resulting in insufficient ground test verification and low utilization of thermal control resources. Therefore, the thermal control scheme for three-dimensionally distributed focal plane assemblies needs to be redesigned. Summary of the Invention

[0003] In view of this, the present invention aims to provide a thermal design device for a three-dimensional distributed focal plane assembly of a space camera. The device uses the detector heat pipe and the imaging processing circuit heat pipe as a common heat dissipation channel for each sub-focal plane. It sets attitude constraints such as the cold end of the heat pipe not being higher than the hot end and arranges them in a consistent parallel direction to ensure synchronous start-up of ground tests. The device uses a single heating loop on the adapter block to achieve unified thermal compensation for all sub-focal planes, which significantly simplifies the system, reduces weight and cost, and improves thermal control reliability and resource utilization.

[0004] To achieve the above objectives, the technical solution created by this invention is implemented as follows: The present invention provides a thermal design device for a three-dimensional distributed focal plane assembly of a space camera, comprising: a frame and multiple sub-focal planes, wherein the multiple sub-focal planes are uniformly attached to the side of the frame by heat insulation pads; The inner surfaces of multiple sub-focal surfaces are sequentially connected to detector heat pipes, and the outer surfaces of multiple sub-focal surfaces are sequentially connected to imaging processing circuit heat pipes. The detector heat pipes and the imaging processing circuit heat pipes are arranged in parallel to each other on multiple sub-focal planes. Both the detector heat pipe and the imaging processing circuit heat pipe include a hot end and a cold end. The hot end and the cold end of the detector heat pipe are on the same horizontal plane, and the hot end and the cold end of the imaging processing circuit heat pipe are on the same horizontal plane; or the cold end of the detector heat pipe is higher than the hot end of the detector heat pipe, and the cold end of the imaging processing circuit heat pipe is higher than the hot end of the imaging processing circuit heat pipe. The cold end of the detector heat pipe and the cold end of the imaging processing circuit heat pipe are connected to one end of the heat dissipation heat pipe through an adapter block. The other end of the heat dissipation heat pipe is connected to a heat sink. The detector heat pipe and the imaging processing circuit heat pipe transfer the heat generated during the operation of the sub-focal surface to the heat sink through the heat dissipation heat pipe. The outer surface of the adapter block is equipped with heating blocks and temperature sensors. The temperature sensors monitor the temperature of multiple sub-focal surfaces in real time and set a temperature threshold. When the temperature of multiple sub-focal surfaces is lower than the temperature threshold, the heating blocks heat the adapter block. The adapter block conducts heat to multiple sub-focal surfaces through the detector heat pipe and the imaging processing circuit heat pipe. When the temperature of multiple sub-focal surfaces is higher than the temperature threshold, the heating blocks stop heating the adapter block.

[0005] Preferably, the sub-focal plane includes a detector, a detector heat-conducting plate, an imaging processing circuit device, and an imaging processing circuit heat-conducting plate; a heat-conducting block is arranged on the detector heat-conducting plate, and the detector is connected to the heat-conducting block; the imaging processing circuit device is connected to the imaging processing circuit heat-conducting plate; the detector heat pipe is connected to the detector heat-conducting plate, and the imaging processing circuit heat pipe is connected to the imaging processing circuit heat-conducting plate; the detector heat-conducting plate is provided with a window for the detector to be photosensitive.

[0006] Preferably, the detector heat pipe is connected to the detector heat-conducting plate via a first pressure plate, and the imaging processing circuit heat pipe is connected to the imaging processing circuit heat-conducting plate via a second pressure plate; a thermally conductive material is filled between the detector heat pipe and the detector heat-conducting plate, and between the detector heat pipe and the first pressure plate; a thermally conductive material is filled between the imaging processing circuit heat pipe and the imaging processing circuit heat-conducting plate, and between the imaging processing circuit heat pipe and the second pressure plate.

[0007] Preferably, the heat-conducting block is a copper heat-conducting block, and GD414 silicone rubber is filled between the copper heat-conducting block and the detector heat-conducting plate; the mating surface between the imaging processing circuit device and the imaging processing circuit heat-conducting plate is filled with an insulating heat-conducting pad.

[0008] Preferably, both the detector heat pipe and the imaging processing circuit heat pipe are aluminum ammonia channel heat pipes, and the bending radius of both the detector heat pipe and the imaging processing circuit heat pipe is greater than 5 times their respective diameters.

[0009] Preferably, the heat insulation pad is composed of a combination of titanium alloy parts and polyimide parts.

[0010] Preferably, the adapter block includes: two aluminum alloy pressure plates with semi-circular grooves, the cold ends of the detector heat pipe and the imaging processing circuit heat pipe are arranged in the semi-circular grooves, and thermally conductive material is filled between the cold ends of the detector heat pipe and the adapter block, and thermally conductive material is filled between the cold ends of the imaging processing circuit heat pipe and the adapter block.

[0011] Preferably, the heating block is a thin-film electric heater, and the temperature sensor is a thermistor.

[0012] Preferably, the outer surfaces of the multiple sub-focal surfaces, except for the detector's photosensitive window, are all covered with multi-layer heat insulation components; the outer surface of the adapter block is covered with multi-layer heat insulation components, and the heating block and temperature sensor are encased within the multi-layer heat insulation components; the outer surface of the frame is covered with multi-layer heat insulation components; the detector heat pipe, except for the connection surface with the first pressure plate and the detector heat-conducting plate, is covered with multi-layer heat insulation components; the imaging processing circuit heat pipe, except for the connection surface with the second pressure plate and the imaging processing circuit heat-conducting plate, is covered with multi-layer heat insulation components; the outer surface of the multi-layer heat insulation components is a polyimide black film.

[0013] Compared with the prior art, the present invention can achieve the following beneficial effects: This invention utilizes a ring-shaped arrangement of detector heat pipes and imaging processing circuit heat pipes as a shared heat dissipation channel for all sub-focal surfaces. This allows detectors on multiple sub-focal surfaces to share a single heat pipe, and imaging processing circuits to share another, avoiding the problem of a surge in the number of heat pipes caused by designing separate heat dissipation paths for each sub-focal surface. Furthermore, a single-path compensation heating circuit is provided only on the heat pipe adapter block to achieve unified thermal compensation temperature control for all sub-focal surfaces. Compared to configuring separate heating circuits and temperature sensors for each sub-focal surface, this invention significantly reduces the number of heat pipes, heaters, temperature sensing elements, and cables, substantially reducing the complexity of the focal surface assembly thermal control system and the overall weight, thus saving valuable launch costs for spacecraft.

[0014] This invention addresses the difficulty of starting up ground tests due to the multi-heatpipe arrangement of a three-dimensional distributed focal plane assembly. It proposes a specific installation constraint where the detector heatpipes and imaging processing circuit heatpipes of each sub-focal plane are arranged in parallel with a consistent overall orientation, and the hot end is no higher than the cold end. This design ensures that all heatpipes can start up synchronously and normally under ground gravity, avoiding insufficient ground test verification due to the failure of individual heatpipes to start. By fully verifying the effectiveness of the thermal control design during the ground phase, the thermal control risks during on-orbit operation are significantly reduced.

[0015] This invention utilizes the reversible heat transfer characteristics of the detector heat pipe and the imaging processing circuit heat pipe. During non-operation periods, the heat generated by the single-path heater on the adapter block is transferred in reverse through the surrounding heat pipe network to each sub-focal surface, achieving simultaneous heat preservation for all detectors and imaging circuits. Compared to multi-path independent heating, single-path centralized heating significantly reduces thermal control power consumption, effectively saving energy. Attached Figure Description

[0016] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments and descriptions of the invention are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a schematic diagram of the thermal design device for a three-dimensional distributed focal plane assembly of a space camera according to an embodiment of the present invention; Figure 2 This is another angle structural schematic diagram of the thermal design device for the three-dimensional distributed focal plane assembly of a space camera provided according to an embodiment of the present invention; Figure 3 This is an exploded view of the frame structure of the thermal design device for the focal plane assembly provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the subfocal surface structure provided according to an embodiment of the present invention.

[0017] The reference numerals in the accompanying drawings include: frame 1, beam splitter 2, detector heat pipe 3, imaging processing circuit heat pipe 4, detector 5, detector heat conduction plate 6, first pressure plate 7, second pressure plate 8, imaging processing circuit heat conduction plate 9, heat insulation pad 10, adapter block 11, heat dissipation heat pipe 12, back plate 13, light transmission channel 14, heat conduction block 15, detector circuit components 16, detector circuit component board 17, imaging processing circuit component board 18, imaging processing circuit components 19, and bottom cover 20. Detailed Implementation

[0018] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and do not constitute a limitation thereof. Similar elements in different embodiments are referred to by associated similar element reference numerals. In the following embodiments, many details are described to facilitate a better understanding of the invention. However, those skilled in the art will readily recognize that some features may be omitted in different situations, or may be replaced by other elements, materials, or methods. In some cases, some operations related to the invention are not shown or described in the specification. This is to avoid obscuring the core parts of the invention with excessive description. For those skilled in the art, detailed description of these related operations is not necessary; the relevant operations can be fully understood based on the description in the specification and general technical knowledge in the art.

[0019] It should be noted that, unless otherwise specified, the embodiments and features described in this invention can be combined to form various implementations. Furthermore, the order of the steps or actions in the method description can be changed or adjusted in a manner readily apparent to those skilled in the art. Therefore, the various orders in the specification and drawings are merely for the clear description of a particular embodiment and do not imply a mandatory order, unless otherwise stated that a particular order must be followed.

[0020] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," and "counterclockwise," etc., indicating orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation on this invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, features defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0021] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0022] The invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0023] Please see Figure 1 In one embodiment of the present invention, a thermal design device for a three-dimensional distributed focal plane assembly of a space camera is provided, comprising: a frame 1 and a plurality of sub-focal planes, wherein the plurality of sub-focal planes are uniformly attached to the side of the frame 1 by heat insulation pads 10. The inner surfaces of multiple sub-focal surfaces are sequentially connected to detector heat pipes 3, and the outer surfaces of multiple sub-focal surfaces are sequentially connected to imaging processing circuit heat pipes 4. The detector heat pipe 3 and the imaging processing circuit heat pipe 4 are arranged in parallel to each other on multiple sub-focal surfaces. Both the detector heat pipe 3 and the imaging processing circuit heat pipe 4 include a hot end and a cold end. The hot end and the cold end of the detector heat pipe 3 are on the same horizontal plane, and the hot end and the cold end of the imaging processing circuit heat pipe 4 are on the same horizontal plane; or the cold end of the detector heat pipe 3 is higher than the hot end of the detector heat pipe 3, and the cold end of the imaging processing circuit heat pipe 4 is higher than the hot end of the imaging processing circuit heat pipe 4. The cold end of the detector heat pipe 3 and the cold end of the imaging processing circuit heat pipe 4 are connected to one end of the heat dissipation heat pipe 12 through the adapter block 11. The other end of the heat dissipation heat pipe 12 is connected to a heat dissipation plate. The detector heat pipe 3 and the imaging processing circuit heat pipe 4 conduct the heat generated during the operation of the sub-focal surface into the heat dissipation plate through the heat dissipation heat pipe 12. The outer surface of the adapter block 11 is equipped with a heating block and a temperature sensor. The temperature sensor monitors the temperature of multiple sub-focal surfaces in real time and sets a temperature threshold. When the temperature of multiple sub-focal surfaces is lower than the temperature threshold, the heating block heats the adapter block 11. The adapter block 11 conducts heat to multiple sub-focal surfaces through the detector heat pipe 3 and the imaging processing circuit heat pipe 4. When the temperature of multiple sub-focal surfaces is higher than the temperature threshold, the heating block stops heating the adapter block 11.

[0024] Please see Figure 2 , Figure 3 and Figure 4The frame 1 is an octagonal prism structure. The top and bottom surfaces of the frame 1 each include four long sides and four short sides. A quadrilateral square cavity is arranged in the center of the top surface of the frame 1. The four corners of the quadrilateral square cavity point to the center of the four long sides of the top surface of the frame 1. Heat insulation pads 10 are evenly distributed at the four corners of the four sides of the four long sides. Quadrilateral light transmission channels 14 are evenly distributed in the center of the four sides of the four long sides.

[0025] Beam splitter 2 is an irregularly shaped, hollowed-out quadrangular pyramid made of silicon carbide material with a coating. Beam splitter 2 has four reflective planes. A cylindrical hollow cavity is located at the center of the bottom surface of beam splitter 2. Beam splitter 2 is mounted on frame 1 via a back plate 13. Back plate 13 is a hollowed-out triangular prism with a cylindrical hollow cavity at its center. The three corners of back plate 13 are fixedly connected to the top surface of frame 1 with screws. Beam splitter 2 is positioned within a quadrilateral square cavity on the top surface of frame 1, embedded in the quadrilateral square cavity at the center of the top surface of frame 1, and then fixedly connected to the top surface of frame 1 via back plate 13. Multiple sub-focal planes are connected to frame 1 via heat insulation pads 10. Heat insulation pads 10 are composite heat insulation pads composed of titanium alloy and polyimide components.

[0026] This embodiment employs four sub-focal planes, each distributed circumferentially along the frame 1. Each sub-focal plane has a flat, plate-like structure and includes: a detector 5, detector circuit components 16, imaging processing circuit components 19, a heat-conducting block 15, a bottom cover 20, a detector heat-conducting plate 6, a detector circuit component board 17, an imaging processing circuit component board 18, and an imaging processing circuit heat-conducting plate 9. The detector heat-conducting plate 6, detector circuit component board 17, imaging processing circuit component board 18, and imaging processing circuit heat-conducting plate 9 are of the same size and are sequentially connected by screws. The side of the sub-focal plane closest to the frame 1 is the detector heat-conducting plate 6. One side of the detector heat-conducting plate 6 is connected to the frame 1 via a heat insulation pad 10. The upper half of the other side of the detector heat-conducting plate 6 has a boss structure, and the lower half of the detector heat-conducting plate 6 has a quadrilateral square cavity corresponding one-to-one with the light-transmitting channel 14 on the side of the frame 1, with the same size as the light-transmitting channel 14. The quadrilateral square cavity serves as the photosensitive window for the detector. One side of the detector circuit board 17 is connected to the side of the detector heat-conducting plate 6 where the boss is located. The upper half of the detector circuit board 17 is provided with detector circuit components 16, the positions of which correspond one-to-one with the positions of the boss structures on the detector heat-conducting plate 6. The detector circuit components 16 and the boss structures on the detector heat-conducting plate 6 are in corresponding contact. An insulating thermal pad is provided on the surface of the detector circuit components 16 to conduct the heat generated during operation to the detector heat-conducting plate 6. The lower half of the detector heat-conducting plate 6 is provided with a conductive... The heat-conducting block 15 is made of copper and has a long strip structure. Its length does not exceed the range of the detector heat-conducting plate 6. The heat-conducting block 15 has bosses at both ends and a groove in the middle. The groove in the middle of the heat-conducting block 15 is used to install the detector 5. The size of the groove matches the size of the detector 5. The detector 5 is the core photosensitive element of the sub-focal plane. The bosses at both ends of the heat-conducting block 15 are fixedly connected to the detector heat-conducting plate 6 by screws. The contact surface is filled with thermally conductive material (e.g., GD414 silicone rubber). The thermally conductive material is used to reduce thermal resistance.

[0027] One side of the imaging processing circuit device board 18 is connected to the other side of the detector circuit device board 17. An imaging processing circuit device 19 is arranged on the other side of the imaging processing circuit device board 18. The other side of the imaging processing circuit device board 18 is connected to one side of the imaging processing circuit heat-conducting plate 9. A boss structure is arranged on one side of the imaging processing circuit heat-conducting plate 9. The position of the imaging processing circuit device 19 on the imaging processing circuit device board 18 corresponds one-to-one with the position of the boss structure on the imaging processing circuit heat-conducting plate 9. The imaging processing circuit device 19 and the boss structure on the imaging processing circuit heat-conducting plate 9 are in corresponding contact. An insulating thermal pad is arranged on the surface of the imaging processing circuit device 19 to conduct the heat generated by the imaging processing circuit device 19 during operation to the imaging processing circuit heat-conducting plate 9, ensuring electrical insulation while efficiently conducting heat.

[0028] A bottom cover 20 is provided at the bottom of the sub-focal surface. The bottom cover 20 is a hollow cuboid structure. The upper surface of the bottom cover 20 is open, and the other five sides are closed. The size of the bottom cover 20 matches the size of the bottom surface formed by connecting the detector circuit device board 17, the detector heat-conducting plate 6, the imaging processing circuit device board 18, and the imaging processing circuit heat-conducting plate 9. The bottom surface formed by connecting the detector circuit device board 17, the detector heat-conducting plate 6, the imaging processing circuit device board 18, and the imaging processing circuit heat-conducting plate 9 is installed in the cavity of the bottom cover 20.

[0029] The inner surface of each sub-focal plane (detector heat-conducting plate 6) is sequentially connected to a detector heat pipe 3, allowing all sub-focal planes to share a single detector heat pipe 3 as a heat dissipation channel. The outer surface of each sub-focal plane (imaging processing circuit heat-conducting plate 9) is sequentially connected to an imaging processing circuit heat pipe 4, allowing all sub-focal planes to share a single imaging processing circuit heat pipe 4 as a heat dissipation channel. The detector heat pipes 3 and imaging processing circuit heat pipes 4 are arranged spatially around the four sub-focal planes, and the detector heat pipes 3 and imaging processing circuit heat pipes 4 have the same diameter.

[0030] Both the detector heat-conducting plate 6 and the imaging processing circuit heat-conducting plate 9 have pre-machined semi-circular grooves that match the diameter of the detector heat pipe 3 and the imaging processing circuit heat pipe 4. The first pressure plate 7 also has a semi-circular groove matching the heat pipe diameter. The detector heat pipe 3 is pressed and fixed into the semi-circular groove of the detector heat-conducting plate 6 by the first pressure plate 7. The second pressure plate 8 also has a semi-circular groove matching the heat pipe diameter. The imaging processing circuit heat pipe 4 is pressed and fixed into the semi-circular groove of the imaging processing circuit heat-conducting plate 9 by the second pressure plate 8. The first pressure plate 7 and the second pressure plate 8 are elongated strip structures, with a length less than the width of the detector heat-conducting plate 6 and the imaging processing circuit heat-conducting plate 9.

[0031] Thermal grease is filled between the detector heat pipe 3 and the detector heat plate 6, between the detector heat pipe 3 and the first pressure plate 7, between the imaging processing circuit heat pipe 4 and the imaging processing circuit heat plate 9, and between the imaging processing circuit heat pipe 4 and the second pressure plate 8 as a thermally conductive material to minimize contact thermal resistance and enhance heat exchange efficiency.

[0032] The heat-conducting plate 6 of the detector, the heat-conducting plate 9 of the imaging processing circuit, the first pressure plate 7, and the second pressure plate 8 are all made of aluminum alloy with high thermal conductivity or high volume aluminum-based composite material.

[0033] Both the detector heat pipe 3 and the imaging processing circuit heat pipe 4 are aluminum ammonia channel heat pipes, with axial capillary channels machined into their internal walls. Both heat pipes are filled with liquid ammonia as the phase change working fluid. To ensure the wall strength at the bends and prevent the internal axial channels from twisting and deforming due to bending, thus blocking the capillary backflow of the working fluid, the bending radii of both the detector heat pipe 3 and the imaging processing circuit heat pipe 4 are designed to be greater than five times their own diameter.

[0034] Both the detector heat pipe 3 and the imaging processing circuit heat pipe 4 include a hot end and a cold end. The hot end is the evaporation section where liquid ammonia absorbs heat, and the cold end is the condensation section where gaseous ammonia releases heat. To ensure the heat pipes can start normally (i.e., the working fluid flows back smoothly) during testing under ground gravity, the spatial arrangement of the detector heat pipe 3 and the imaging processing circuit heat pipe 4 must meet specific positional constraints: the hot end of the detector heat pipe 3 must not be higher than the cold end of the detector heat pipe 3, and the hot end of the imaging processing circuit heat pipe 4 must not be higher than the cold end of the imaging processing circuit heat pipe 4. Specifically, there are two arrangement forms: the hot end and cold end of the detector heat pipe 3 are on the same horizontal plane, and the hot end and cold end of the imaging processing circuit heat pipe 4 are on the same horizontal plane; or the cold end of the detector heat pipe 3 is higher than the hot end of the detector heat pipe 3, and the cold end of the imaging processing circuit heat pipe 4 is higher than the hot end of the imaging processing circuit heat pipe 4. Through this positional constraint, gravity-assisted capillary force can be effectively used to achieve the reflux of the working fluid, ensuring the normal start-up of the ground test. On a single sub-focal plane, the detector heat pipe 3 and the imaging processing circuit heat pipe 4 are arranged parallel to each other, and their overall orientation remains consistent across all sub-focal planes. This parallel and consistent arrangement ensures that all heat pipes are synchronously affected by gravity under the same spatial orientation when the ground test position is changed, thus enabling them to start up synchronously and normally.

[0035] The cold ends of the detector heat pipe 3 and the imaging processing circuit heat pipe 4 converge and connect to the same adapter block 11. The adapter block 11 consists of two aluminum alloy plates with semi-circular grooves machined on them. Each aluminum alloy plate has three semi-circular grooves arranged side-by-side from top to bottom. The cold ends of the detector heat pipe 3 and the imaging processing circuit heat pipe 4 are respectively clamped and fixed within the upper and lower semi-circular grooves. Thermal grease is filled between the cold ends of the detector heat pipe 3 and the adapter block 11, and between the cold ends of the imaging processing circuit heat pipe 4 and the adapter block 11, to enhance heat conduction.

[0036] The semi-circular groove in the middle of the adapter block 11 is thermally connected to one end of the heat pipe 12. The connection between the adapter block 11 and the heat pipe 12 is filled with thermally conductive grease as a thermally conductive material. The other end of the heat pipe 12 is connected to an external heat sink. The heat generated during the operation of the sub-focal plane is sequentially transferred to the adapter block 11 via the detector heat pipe 3 and the imaging processing circuit heat pipe 4, then transferred from the adapter block 11 to the heat pipe 12, and finally transferred to the external heat sink through the heat pipe 12. The heat sink then radiates the heat into the cold black space to dissipate the heat. Multiple sub-focal planes share a single heat pipe 12 and a heat sink, greatly simplifying the heat dissipation path.

[0037] To reduce dark current and noise in detector 5, the operating temperature of the sub-focal surfaces needs to be designed to be lower than that of other components of the space camera (such as frame 1, beam splitter 2, etc.). To reduce heat leakage from other components to the sub-focal surfaces, on the one hand, the heat insulation pads 10 between each sub-focal surface and frame 1 are composite heat insulation pads composed of layers of titanium alloy and polyimide components. Titanium alloy has low thermal conductivity, and polyimide has extremely low thermal conductivity; the combination of the two can significantly reduce heat leakage from frame 1 to the sub-focal surfaces. On the other hand, except for the light-sensing window of detector 5 (to avoid blocking light), each sub-focal surface is tightly covered with multiple layers of heat insulation components. The outer surface of the adapter block 11 is also covered with a multi-layer heat insulation component. The heating block and temperature sensor are encased within the multi-layer heat insulation component, and the outer surface of the frame 1 is also covered with a multi-layer heat insulation component. The detector heat pipe 3, except for its connection surfaces with the first pressure plate 7 and the detector heat-conducting plate 6, is covered with a multi-layer heat insulation component. The imaging processing circuit heat pipe 4, except for its connection surfaces with the second pressure plate 8 and the imaging processing circuit heat-conducting plate 9, is also covered with a multi-layer heat insulation component. The surface of all materials in the multi-layer heat insulation components is coated with a polyimide black film, which effectively reduces the influence of stray light near the sub-focal plane on imaging.

[0038] A thin-film electric heater is attached to the outer surface of one of the aluminum alloy pressure plates of the adapter block 11 as a heating block, and a thermistor is attached to the outer surface of the other aluminum alloy pressure plate as a temperature sensor. Both the thin-film electric heater and the thermistor are connected to the camera's temperature control circuit via wires, forming a closed-loop temperature control circuit to achieve thermal compensation temperature control for all sub-focal surfaces. The working principle is as follows: During non-operational periods of the space camera, the temperature sensor monitors the temperature status of each sub-focal surface in real time and presets a stored temperature threshold. When the temperature of each sub-focal surface detected by the temperature sensor is lower than the temperature threshold, the temperature control circuit controls the heating block to be powered on and start heating the adapter block 11. Heat is transferred from the adapter block 11 through contact conduction to the cold end of the detector heat pipe 3 and the cold end of the imaging processing circuit heat pipe 4, and further transferred via heat pipes to the detector heat-conducting plate 6 and the imaging processing circuit heat-conducting plate 9 of each sub-focal surface, and finally conducted to the detector 5 and the imaging processing circuit device 19, ensuring that the temperature of each sub-focal surface during non-operational periods is never lower than its stored temperature threshold.

[0039] When the temperature sensor detects that the temperature of each sub-focal surface is higher than the preset temperature threshold, the temperature control circuit cuts off the power supply to the heating block and stops heating. By intermittently operating the above-mentioned single heating circuit, accurate thermal compensation for all sub-focal surfaces is achieved, reducing the number of heating circuits and simplifying the thermal control system.

[0040] In summary, the above description is merely a preferred embodiment of this specification and is not intended to limit the scope of protection of this specification. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this specification should be included within the scope of protection of this specification.

[0041] The systems, apparatuses, 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, a 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 any combination of these devices.

[0042] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0043] The various embodiments in this specification are described in a progressive manner. Similar or identical parts between embodiments can be referred to interchangeably. Each embodiment focuses on describing the differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments.

Claims

1. A thermal design device for a three-dimensional distributed focal plane assembly of a space camera, characterized in that, include: A frame and multiple sub-focal surfaces, wherein the multiple sub-focal surfaces are uniformly attached to the side of the frame by heat insulation pads; The inner surfaces of the plurality of sub-focal surfaces are sequentially connected to detector heat pipes, and the outer surfaces of the plurality of sub-focal surfaces are sequentially connected to imaging processing circuit heat pipes. The detector heat pipe and the imaging processing circuit heat pipe are arranged parallel to each other on the multiple sub-focal surfaces; Both the detector heat pipe and the imaging processing circuit heat pipe include a hot end and a cold end. The hot end and the cold end of the detector heat pipe are on the same horizontal plane, and the hot end and the cold end of the imaging processing circuit heat pipe are on the same horizontal plane; or the cold end of the detector heat pipe is higher than the hot end of the detector heat pipe, and the cold end of the imaging processing circuit heat pipe is higher than the hot end of the imaging processing circuit heat pipe. The cold end of the detector heat pipe and the cold end of the imaging processing circuit heat pipe are connected to one end of the heat dissipation heat pipe via an adapter block. The other end of the heat dissipation heat pipe is connected to a heat dissipation plate. The detector heat pipe and the imaging processing circuit heat pipe transfer the heat generated during the operation of the sub-focal surface to the heat dissipation plate through the heat dissipation heat pipe. The outer surface of the adapter block is equipped with a heating block and a temperature sensor. The temperature sensor monitors the temperature of the multiple sub-focal surfaces in real time and sets a temperature threshold. When the temperature of the multiple sub-focal surfaces is lower than the temperature threshold, the heating block heats the adapter block. The adapter block conducts heat to the multiple sub-focal surfaces through the detector heat pipe and the imaging processing circuit heat pipe. When the temperature of the multiple sub-focal surfaces is higher than the temperature threshold, the heating block stops heating the adapter block.

2. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 1, characterized in that, The subfocal plane includes a detector, a detector heat-conducting plate, an imaging processing circuit device, and an imaging processing circuit heat-conducting plate; a heat-conducting block is arranged on the detector heat-conducting plate, and the detector is connected to the heat-conducting block; the imaging processing circuit device is connected to the imaging processing circuit heat-conducting plate; the detector heat pipe is connected to the detector heat-conducting plate, and the imaging processing circuit heat pipe is connected to the imaging processing circuit heat-conducting plate; the detector heat-conducting plate is provided with a window for the detector to sense light.

3. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 2, characterized in that, The detector heat pipe is connected to the detector heat-conducting plate via a first pressure plate, and the imaging processing circuit heat pipe is connected to the imaging processing circuit heat-conducting plate via a second pressure plate; a thermally conductive material is filled between the detector heat pipe and the detector heat-conducting plate, and between the detector heat pipe and the first pressure plate; a thermally conductive material is filled between the imaging processing circuit heat pipe and the imaging processing circuit heat-conducting plate, and between the imaging processing circuit heat pipe and the second pressure plate.

4. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 2, characterized in that, The heat-conducting block is a copper heat-conducting block, and GD414 silicone rubber is filled between the copper heat-conducting block and the detector heat-conducting plate; the mating surface between the imaging processing circuit device and the imaging processing circuit heat-conducting plate is filled with an insulating heat-conducting pad.

5. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 1, characterized in that, Both the detector heat pipe and the imaging processing circuit heat pipe are aluminum ammonia channel heat pipes. The bending radius of the detector heat pipe and the bending radius of the imaging processing circuit heat pipe are both greater than 5 times the diameter of the detector heat pipe and the imaging processing circuit heat pipe.

6. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 1, characterized in that, The heat insulation pad is composed of titanium alloy parts and polyimide parts.

7. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 1, characterized in that, The adapter block includes two aluminum alloy pressure plates with semi-circular grooves. The cold ends of the detector heat pipe and the imaging processing circuit heat pipe are arranged in the semi-circular grooves. Thermally conductive material is filled between the cold ends of the detector heat pipe and the adapter block. Thermally conductive material is also filled between the cold ends of the imaging processing circuit heat pipe and the adapter block.

8. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 1, characterized in that, The heating block is a thin-film electric heater, and the temperature sensor is a thermistor.

9. The thermal design device for the three-dimensional distributed focal plane assembly of a space camera according to claim 3, characterized in that, The outer surfaces of the plurality of sub-focal surfaces, except for the photosensitive window of the detector, are all covered with multi-layer heat insulation components; the outer surface of the adapter block is covered with multi-layer heat insulation components, and the heating block and the temperature sensor are encased within the multi-layer heat insulation components; the outer surface of the frame is covered with multi-layer heat insulation components; the detector heat pipe, except for the connection surface with the first pressure plate and the detector heat-conducting plate, is covered with multi-layer heat insulation components; the imaging processing circuit heat pipe, except for the connection surface with the second pressure plate and the imaging processing circuit heat-conducting plate, is covered with multi-layer heat insulation components; the outer surface of the multi-layer heat insulation components is a polyimide black film.

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