A heat control method and device for improving performance of a lunar orbit laser corner reflector

Abstract

The application discloses a heat control method and device for improving performance of a lunar orbit laser corner reflector, and belongs to the technical field of aerospace. The method comprises the following steps: in a non-test stage, analyzing the illumination and thermal environment data of the corner reflector in a lunar orbit, and designing heat dissipation and heat insulation measures so that the corner reflector is in a low-temperature storage stage; in a preparation test stage, starting a heating belt for preheating, collecting temperature data of each region of the corner reflector, combining a novel PID temperature control algorithm and an external heat flow prediction model, and independently adjusting the duty cycle of each heating belt; in a test process, starting the heating belt, and performing real-time monitoring and adjustment on each region of the corner reflector; when the temperature deviates, the duty cycle of the heating belt is adjusted through the novel PID temperature control algorithm and the external heat flow prediction model; and after the test is completed, the corner reflector reenters the low-temperature storage stage. The application can ensure high precision and high reliability of the laser corner reflector in the lunar orbit, and improves the success probability of laser ranging of the corner reflector on a lunar orbit spacecraft on the ground.

Description

Technical Field

[0001] This invention belongs to the field of aerospace technology, specifically relating to a thermal control method and device for improving the performance of a lunar orbit laser corner reflector. Background Technology

[0002] The application of laser corner reflectors in lunar orbit currently faces a series of challenges, particularly in the precise control of thermal deformation. Laser corner reflectors are high-precision distance measurement devices. Typically mounted externally on satellites, their operating temperature fluctuates due to factors such as direct sunlight, infrared radiation, and solar reflection during satellite operation. The measurement accuracy of the laser corner reflector optical system, particularly its trihedral angle, is highly sensitive to temperature; the success of laser ranging is largely determined by the measurement error of the laser corner reflector. To ensure the measurement accuracy of the laser corner reflector optical system, increasingly stringent thermal control requirements are being placed on the laser corner reflector. Current technologies utilize large-aperture single-unit laser corner reflectors to improve the accuracy of lunar laser ranging, but the increased aperture of the laser corner reflector also introduces challenges in thermal control.

[0003] The extreme temperature variations in the lunar space environment and the uneven illumination of the laser corner reflector cause localized deformation of the laser corner reflector material due to thermal expansion and contraction, affecting ranging accuracy. Current thermal control designs, due to the relatively low requirements for laser corner reflector specifications, generally employ a passive-based, supplementary active thermal control scheme. This involves multi-layered encapsulation and active temperature control of the mounting surface. This approach can generally meet the requirements for laser corner reflectors in near-Earth orbit. However, for laser corner reflectors and their assemblies with higher specifications, such as those in lunar orbit, precise temperature gradient control is impossible. Therefore, relying solely on the above methods is insufficient to meet the measurement requirements.

[0004] For the thermal control of laser corner reflector assemblies in satellite components, the temperature rise requirements can generally be met by heater power compensation. The key and difficult point of thermal control design is how to avoid excessive temperature gradients and keep the temperature of each position of the corner reflector consistent, so as not to cause a decrease in optical performance due to local temperature unevenness and thermal deformation. Summary of the Invention

[0005] To address the aforementioned technical problems, this invention provides a thermal control method and apparatus for improving the performance of a lunar orbit laser corner reflector. This method solves the problem of reduced accuracy caused by thermal deformation of the laser corner reflector (hereinafter referred to as the corner reflector) in lunar orbit, ensuring the thermal stability and thermal gradient of the corner reflector in lunar orbit, so that the overall temperature and temperature gradient of the corner reflector are within the required range, thereby improving the optical performance of the lunar orbit spaceborne laser corner reflector in complex space thermal environments.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A thermal control method for improving the performance of a lunar orbit laser corner reflector includes the following steps:

[0008] Step 1: In the non-experimental phase, analyze the radiation and thermal environment data of the corner reflector in lunar orbit, and design heat dissipation or insulation measures to keep the corner reflector in a low-temperature storage phase.

[0009] Step 2, Preparation for the test: Start the heating belt to preheat, collect temperature data of each area of ​​the corner reflector, and adjust the duty cycle of each heating belt independently by combining the PID temperature control algorithm and the external heat flow prediction model to ensure that the temperature gradient meets the requirements.

[0010] Step 3: During the test: Start the heating belt, monitor and adjust each area of ​​the corner reflector in real time. When the temperature deviates, adjust the duty cycle of the heating belt through the PID temperature control algorithm and the external heat flow prediction model.

[0011] Step 4: After completing the test, the satellite attitude maneuvers back to the conventional solar panel sun-oriented mode, and the corner reflector re-enters the cryogenic storage stage.

[0012] Furthermore, in step 1, the 'low temperature' refers to a temperature lower than the operating temperature of the corner reflector. This is to facilitate precise temperature control through heating during the testing phase and to avoid excessively high temperatures during the storage phase, which could lead to difficulties in temperature control later.

[0013] Furthermore, each region of the corner reflector includes the corner reflector body and its lens mount, spacer ring, back cover, and mounting structure area. Each region is equipped with an independent heating belt and a PID controller connected to the heating belt.

[0014] Furthermore, in step 2, the external heat flow prediction model adjusts the heating zone duty cycle in advance at locations where a significant change in the external heat flow is predicted.

[0015] Furthermore, in step 2 or step 3, the novel PID control algorithm calculates and adjusts the power regulation of the heating belt according to the following formula. ,in, These represent the proportional, integral, and derivative adjustments of the PID controller, as well as the external heat flow correction.

[0016] Furthermore, the proportional adjustment amount , The proportional gain determines the controller's responsiveness to the current deviation; the integral part... = , The integral coefficients are used to eliminate the steady-state error of the system; the differential part... = , The differential coefficients are used to predict the trend of deviation changes; external heat flow compensation section. This represents the compensation term for temperature fluctuations caused by external heat flow during satellite attitude maneuvers; e represents the deviation between the desired corner reflector operating temperature and the current corner reflector temperature obtained in real time from the temperature sensor.

[0017] Furthermore, the corner reflector is covered with a thermal control multilayer and an OSR reflective surface, and a light shield is installed on the front side of the corner reflector. The corner reflector is made of solid glass.

[0018] Furthermore, the heating band includes multiple heating elements, each with an irregular shape that fits perfectly against the surface of the corner reflector.

[0019] Furthermore, the edges of the heating band are serrated, and the serrated edges of adjacent heating bands completely match.

[0020] On the other hand, the present invention provides a thermal control device for improving the performance of a lunar orbit laser corner reflector, applied to the aforementioned thermal control method for improving the performance of a lunar orbit laser corner reflector, the device comprising:

[0021] The temperature measurement module is used to divide the corner reflector into multiple temperature measurement zones, each of which includes a temperature sensor;

[0022] An active temperature control module is used to independently and actively control multiple temperature measurement zones. Each temperature measurement zone includes an independently controlled irregularly shaped heating belt. The heating belt is connected to a PID controller, which adjusts the duty cycle of the heating belt to achieve precise temperature control in each zone based on data from the temperature measurement module and an external heat flow prediction model.

[0023] The passive temperature control module is used to install a thermal control multilayer, OSR reflective surface and sunshade on the outside of the corner reflector to achieve heat insulation and reflection of solar radiation.

[0024] The control module is used to combine satellite orbital attitude data and external heat flow prediction model to dynamically adjust the external heat flow correction term of the PID controller, and coordinate the active and passive temperature control modules to ensure that the overall temperature and temperature gradient of the corner reflector meet the index requirements.

[0025] The beneficial effects of this invention are as follows:

[0026] This invention divides the corner reflector into multiple temperature-controlled zones, utilizes a novel PID temperature control system with heating elements for real-time precision, introduces an external heat flow compensation mechanism, and incorporates a uniquely shaped, serrated edge heating element design to ensure a smooth temperature transition between zones. Temperature differences between adjacent zones can be controlled within a minimal range, which helps prevent thermal deformation caused by uneven temperature distribution, thereby improving the accuracy of laser reflection. This is crucial for high-precision measurement tasks such as Earth-Moon laser ranging.

[0027] The low-temperature design during the non-testing phase ensures that the corner reflector is stored at a temperature lower than its operating temperature. This avoids the problem of the corner reflector area exceeding the operating temperature during the testing phase, which would prevent rapid heat dissipation and cooling, thus avoiding large temperature gradient changes that could cause thermal deformation and affect performance. During the non-testing phase, conventional loads are not intentionally kept below the operating temperature. Without active cooling devices, there is a risk that the ambient temperature may be too high during operation, making it impossible to reduce the temperature back to the operating range.

[0028] During the experimental phase, the temperature was rapidly and accurately adjusted to the operating temperature and maintained stably using a novel PID algorithm. A stable operating temperature ensures consistent optical performance and reflection characteristics of the laser corner reflector, improving the accuracy and reliability of ranging. The novel PID temperature control algorithm incorporates an external heat flux compensation term, taking into account satellite orbit and attitude, as well as the influence of internal heating elements, to predict and compensate for changes in external heat flux. This enables precise control of the corner reflector temperature and temperature uniformity, ensuring on-orbit optical performance.

[0029] Besides the laser incident surface, the sides and bottom (three-sided corners) of the corner reflector are evenly covered with flexible electric heating elements. These heating elements are irregularly shaped and fit perfectly against the reflector surface. The edges of the heating elements are serrated, and the serrated edges of adjacent heating elements perfectly match. This ensures that the temperature control areas covered by different heating elements have a gradual temperature transition even when the target temperatures are inconsistent, preventing excessive temperature gradients. The remaining structural components outside the corner reflector also implement active temperature control measures as needed, following the same approach.

[0030] The synergistic effect of the sunshade, OSR reflector, and thermal control multilayer material in the thermal control system creates an optimized thermal environment for the corner reflector. The sunshade prevents direct sunlight from reaching the interior of the corner reflector, the OSR reflector reflects solar radiation heat, reducing the heat absorbed by the corner reflector, and the thermal control multilayer material provides both insulation and heat preservation. This combination allows the corner reflector to maintain good operating performance in the complex lunar orbit thermal environment. For example, during non-experimental periods, it ensures the corner reflector remains at a lower temperature, facilitating precise and uniform temperature control when heating it to operating temperature. This avoids the added weight, power consumption, and complexity of introducing active cooling modules. Under high temperatures such as direct sunlight, the internal temperature of the corner reflector does not become excessively high due to the large influx of external heat, thus ensuring normal operation and preventing performance degradation caused by overheating, effectively improving its performance.

[0031] The heating belt employing a PID control algorithm specifically designed for corner reflectors enables highly efficient temperature regulation. Based on real-time monitored temperature data and external heat flow compensation, the PID controller quickly calculates and adjusts the heating belt's power, allowing the corner reflector to rapidly reach its operating temperature. Furthermore, throughout the entire operation, it can adjust promptly according to temperature changes, ensuring the temperature consistently meets requirements. Compared to traditional temperature regulation methods, this approach is more precise and efficient, reducing adjustment time and thus improving overall work efficiency. Attached Figure Description

[0032] Figure 1 This is a flowchart of a thermal control method for improving the performance of a lunar orbit laser corner reflector.

[0033] Figure 2 This invention describes the external shape and basic working principle of the corner reflector body.

[0034] Figure 3 This is a structural diagram of the corner reflector body and heating element of the present invention;

[0035] Figure 4 This is a diagram showing the distribution structure of the heating elements. Detailed Implementation

[0036] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0037] like Figure 1 The diagram shown is a flowchart of a thermal control method for improving the performance of a lunar orbit laser corner reflector according to the present invention, which specifically includes the following steps:

[0038] Step 1: In the non-experimental phase, by analyzing the radiation and thermal environment data of the corner reflector in lunar orbit, heat dissipation or heat insulation measures are designed to keep the corner reflector in a low-temperature storage phase, where low temperature means below the operating temperature.

[0039] Step 2, Experiment Preparation Stage: (e.g.) Figure 2 The diagram illustrates the external shape and basic working principle of the corner reflector in this invention. The corner reflector is made of solid glass, with its bottom composed of three mutually perpendicular reflective surfaces, resembling a three-dimensional angle, hence the name "trihedral." Its basic working principle is as follows: when electromagnetic waves or light waves are incident on the corner reflector, after being reflected sequentially by the three reflective surfaces, the reflected waves return in a direction parallel to the incident waves, thus achieving efficient reflection of the incident waves. This has important applications in fields such as laser ranging. The "trihedral" formed by the three reflective surfaces is the core area for precise temperature control.

[0040] The heating belts are preheated, and the temperature control module collects temperature measurements from each area, implementing a novel PID temperature control system. Each heating belt is independently controlled to begin preheating. Simultaneously, by pre-loading the attitude maneuver commands to be executed, and based on the model's prediction of external heat flow, the novel PID algorithm is adjusted and corrected. The heating belt duty cycle is adjusted in advance at locations where significant changes in predicted external heat flow are expected. This ensures that the temperature and temperature gradient in each controlled area meet the requirements.

[0041] Step 3: During the test: Start the heating belt and monitor and adjust the temperature of the corner reflector in real time. When the temperature deviates, adjust the duty cycle of the heating belt through the PID controller (with external heat flow model correction).

[0042] Step 4: After completing the test, the satellite attitude maneuvers back to the conventional solar panel sun-oriented mode, and the corner reflector re-enters the cryogenic storage stage.

[0043] In step 1, the purpose of lowering the corner reflector temperature during the storage phase is to facilitate precise temperature control of different areas of the corner reflector using PID temperature management of the heating elements, ensuring uniform temperature distribution and preventing excessive temperature gradients. Otherwise, if the corner reflector itself experiences excessively high temperatures in a single area due to sunlight exposure or the heat dissipation of high-power units on the satellite, it would be difficult to compensate for this through the heating elements in other areas. Adding additional active cooling or heat dissipation functions would significantly increase the satellite's cost and complexity. Therefore, designing a low-temperature thermal environment for the corner reflector during the storage phase is an easy-to-operate, energy-saving method that facilitates temperature gradient control.

[0044] In steps 2 and 3, a novel PID temperature control algorithm was employed, introducing an external heat flow correction term into the traditional PID temperature control algorithm. Since the corner reflector is installed externally with thermal insulation, the external heat flow of the lunar orbiting satellite mainly comes from sunlight. Due to satellite attitude adjustments, the angle and position of sunlight exposure change, causing variations in the external heat flow and thus affecting the temperature regulation accuracy of the corner reflector. An external heat flow variation model was established based on the satellite's orbit and attitude conditions, allowing for advance compensation and adjustment of the impact of external heat flow changes in the algorithm control.

[0045] The PID controller is used to adjust the power output of the heating element based on the temperature feedback signal. By setting the parameters of the PID controller, a PWM signal is output to control the heater's operation, achieving rapid response and stable control of the diagonal temperature response. Traditional PID parameters include proportional, integral, and derivative; this invention introduces an external heat flow correction term into the PID parameter control terms.

[0046] The novel PID control algorithm calculates and adjusts the power regulation of the heating belt according to the following formula. ,in, These represent the proportional, integral, and derivative control parameters of the PID controller, as well as the external heat flux correction. The temperature is controlled within the set range by adjusting the duty cycle of the heating element. The proportional control parameter... , The proportional gain determines the controller's responsiveness to the current deviation; the integral part... = , The integral coefficients are used to eliminate the steady-state error of the system; the differential part... = , The differential coefficients are used to predict the trend of deviation changes; external heat flow compensation section. This represents the compensation term for temperature fluctuations caused by external heat flow during satellite attitude maneuvers; 'e' represents the deviation between the desired corner reflector operating temperature and the current corner reflector temperature obtained in real-time from temperature sensors. For example, for a specific heated area, a conventional PID algorithm calculates that the duty cycle for maintaining the target temperature in the heated area is 50%. However, the satellite is about to maneuver to this area where it will be directly exposed to sunlight, and the mounting surface in this area will be powered on during a period of high power consumption. At this time, the computer calculates and adjusts the duty cycle in advance based on the external heat flow change model to compensate for the impending changes in external heat flow, thereby further reducing the temperature fluctuations of the satellite.

[0047] Based on the above method, the present invention also provides a thermal control device for improving the performance of a lunar orbit laser corner reflector, comprising:

[0048] The temperature measurement module divides the corner reflector into multiple temperature measurement zones to accurately measure the temperature of the laser corner reflector body, its lens mount, spacer, and back cover, etc., in order to determine the temperature gradient distribution of the entire corner reflector unit. The selection of sensors takes into account measurement accuracy, response time, and stability in extreme environments.

[0049] The active temperature control module divides the corner reflector into multiple temperature control zones by distributing different heating bands. It employs a novel PID algorithm for precise temperature control of the corner reflector body, its mount, spacer, and back cover. Each temperature control zone is equipped with a heating band and includes a PID controller connected to the heating band for real-time and precise temperature control of each zone, ensuring the overall temperature and temperature gradient of the corner reflector remain within the required range. Each temperature control zone corresponds one-to-one with the temperature measurement zone.

[0050] Passive temperature control module: The corner reflector is wrapped with a thermal control multilayer, a multilayer thermal insulation material used for spacecraft thermal control. It consists of multiple layers of aluminized polyester film and other materials, separated by spacers. Its principle is to effectively block heat conduction and radiation through multilayer reflection and low thermal conductivity, thereby providing a stable temperature environment for the spacecraft's internal equipment. The outer side of the thermal control multilayer is covered with an OSR reflector to reduce the impact of extreme temperatures such as direct sunlight and the cold background of deep space on the corner reflector.

[0051] Furthermore, it also includes a control unit, which combines the measurement data from the temperature measurement module with the external heat flow model corresponding to the satellite's orbital position and attitude to control the temperature settings of the active and passive temperature control modules, adjust the duty cycle of the electric heating belt output, and ensure that the overall temperature and temperature gradient of the corner reflector are within the required index range. The control unit's functions are uniformly calculated by the onboard integrated electronic unit.

[0052] Furthermore, the passive temperature control module includes a multi-layer thermal control system with multiple layers of material for heat insulation and preservation of the corner reflector. These multi-layer materials are carefully selected based on thermophysical properties such as thermal conductivity, heat capacity, and emissivity to achieve effective temperature control of the corner reflector.

[0053] Furthermore, the passive temperature control module wraps an additional OSR reflector around the outer layer of the corner reflector's thermal control multilayer. During solar irradiation, the OSR heat dissipation surface effectively reflects solar radiation, significantly reducing the heat absorbed by the corner reflector. For example, under direct sunlight, without the OSR heat dissipation surface, the surface temperature of the corner reflector might rise rapidly due to the absorption of solar radiation; however, with the OSR heat dissipation surface, the temperature rise is greatly reduced, potentially by tens of degrees Celsius compared to when there is no OSR heat dissipation surface. The specific value depends on factors such as solar radiation intensity, irradiation time, and the reflectivity of the OSR heat dissipation surface. In low-temperature design during non-experimental phases, the OSR heat dissipation surface helps maintain the corner reflector's low-temperature storage state. During the experimental phase, it also helps stabilize the temperature of each temperature-controlled area, preventing localized overheating.

[0054] Furthermore, the laser corner reflector is made of solid material, and each temperature-controlled area is the corner reflector body. Multiple flexible electric heating elements are distributed on the sides and bottom surface (excluding the incident surface) of the temperature-controlled area. Each heating element comprises multiple heating components, with each heating element corresponding to one of the temperature-controlled areas of the corner reflector. The heating element has an irregular shape and is designed to fully conform to the corner reflector surface. The edges of the electric heating elements are serrated, and the serrated edges between adjacent heating elements can perfectly match. This ensures that the temperature control areas covered by different heating elements have a gradual temperature transition even when the target temperatures are inconsistent, preventing excessive temperature gradients. The remaining structural components outside the corner reflector body also implement active temperature control measures as needed, following the methods described above. Figure 3 The diagram shows the temperature measuring point structure of the corner reflector body and heating elements of the present invention. Different heating elements on the surface of the body are distinguished by different filling patterns. (Preferably, the corner reflector body has six heating elements and temperature measuring points, symmetrically distributed, as shown in the diagram.) Figure 4 As shown in the figure, the edges of the heating element are arranged in a serrated pattern to ensure a consistent temperature gradient.

[0055] Example:

[0056] Before the laser corner reflector test (non-test phase), based on the irradiation conditions and thermal environment analysis of the corner reflector in lunar orbit, a low-temperature design was implemented for the corner reflector's thermal environment during the non-test phase. Excess heat was dissipated through the heat dissipation surface, ensuring that the overall storage temperature of the corner reflector was lower than the operating temperature and guaranteeing a uniform temperature gradient. The temperature control and measurement module monitored the temperature in real time, activating the heating module if the temperature threshold was exceeded.

[0057] Preparation for the test phase: Before ranging begins, the satellite's attitude is adjusted to ensure that the laser corner reflector receives solar radiation evenly, reducing the risk of localized overheating. Simultaneously, the visibility of the satellite antenna relative to the ground control station, the visibility of the star sensor, and the solar panel's visibility to the sun must be comprehensively considered. Dynamic model simulations are used to ensure that satellite telemetry signals are consistently received during ranging, that attitude-sensitive devices remain in normal operating condition, and that power is sufficient. To meet these constraints, the satellite's attitude can be adjusted for necessary attitude offset maneuvers at other angles, provided that the corner reflector remains aligned with the ground.

[0058] After determining the expected attitude adjustment of the satellite during the test, the satellite computer will perform illumination analysis and calculation based on the attitude situation to obtain the illumination status of the corner reflector during the test, i.e., the change in external heat flow, which will be used as the external heat flow correction term in the temperature control algorithm and output to the temperature control module in real time.

[0059] 1.5 hours before ranging begins, the PID controller is activated in precise temperature control mode. Based on real-time temperature data and changes in external heat flow calculated by the spacecraft computer, the power output of the heating belt is adjusted in real time, and the PWM duty cycle is adjusted to compensate for changes in external heat flow. This maintains the corner reflector temperature precisely within the set range.

[0060] During the experiment, ensure that the temperature gradient at each location is maintained within 0.1℃, and the average temperature is maintained at 20±0.1℃.

[0061] During the testing phase, the heating element in the thermal control device was activated, and PID control was employed to ensure consistent temperature gradient adjustment. The passive thermal control system for the individual laser corner reflector unit was designed with a multi-layered material and OSR film covering its mounting surface and body, along with a light shield. These materials include, but are not limited to, high-reflectivity metal foil, heat-insulating ceramic layers, low-emissivity coatings, and high-reflectivity OSR materials. The selection and layer configuration of these materials aim to minimize the impact of the external thermal environment on the corner reflector's temperature. The light shield prevents direct sunlight while minimizing stray light interference.

[0062] Temperature sensors, such as thermocouples, thermistors, or temperature sensors, are installed at different locations on the corner reflector. These sensors are evenly distributed within a predefined temperature control zone to ensure comprehensive monitoring of the temperature distribution. Heating belts are installed at critical locations on the corner reflector, such as edges and areas with large temperature gradients. The heating belts are managed by a PID controller, which adjusts the output of the heating belts in real time based on data from the temperature measurement module. Six heating belts and temperature measurement points are set on the main body of the corner reflector, and several heating belts and temperature measurement points are set on the outer shell and structural components of the corner reflector. The positions of the temperature measurement points and heating belts correspond one-to-one. The corner reflector points towards the direction of the Earth laser station. Traditional thermal control methods only focus on local temperature measurement points and cannot obtain changes in the overall temperature gradient. Traditional PID temperature control algorithms do not consider changes in external heat flow caused by attitude changes and do not compensate for such changes in advance. When the corner reflector is exposed to sunlight in different areas for a long time, local overheating and over-temperature are likely to occur, resulting in excessive temperature gradients and the risk of thermal deformation. These factors can cause even small deformations of the corner reflector, leading to a decrease in on-orbit optical performance. However, based on the above measures of the present invention, the on-orbit performance of the laser corner reflector will remain optimal, thereby increasing the probability of successful lunar orbit-to-ground ranging.

[0063] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above descriptions are merely specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A thermal control method for improving the performance of a lunar orbit laser corner reflector, characterized in that, Includes the following steps: Step 1: In the non-experimental phase, analyze the illumination and thermal environment data of the corner reflector in lunar orbit, and design heat dissipation or heat insulation measures to keep the corner reflector in a low-temperature storage phase, where low temperature means 5~10℃ below the operating temperature. Step 2, Preparation for the test: Start the preheating of multiple independently controlled irregular heating belts, collect temperature measurement data of each area of ​​the corner reflector, and combine the new PID control algorithm and external heat flow prediction model to independently adjust the duty cycle of each heating belt to ensure that the temperature gradient meets the requirements. Step 3: During the test: Start the heating belt and monitor and adjust each area of ​​the corner reflector in real time. When the temperature deviates, adjust the duty cycle of the heating belt through the new PID temperature control algorithm and external heat flow prediction model. Step 4: After the test is completed, the satellite attitude maneuvers back to the normal solar panel orientation attitude, and the corner reflector re-enters the cryogenic storage stage; The novel PID control algorithm calculates and adjusts the power regulation of the heating belt according to the following formula. ,in, These represent the proportional, integral, and derivative control parameters of the PID controller, respectively, and the external heat flow correction parameter. Dynamic adjustments are made based on satellite orbital attitude data and external heat flow prediction models to compensate for temperature fluctuations caused by external heat flow during satellite attitude maneuvers.

2. The thermal control method for improving the performance of a lunar orbit laser corner reflector according to claim 1, characterized in that, Each area of ​​the corner reflector includes the corner reflector body and its lens mount, spacer ring, back cover, and mounting structure area. Each area is equipped with an independent heating belt and a PID controller connected to the heating belt.

3. The thermal control method for improving the performance of a lunar orbit laser corner reflector according to claim 1, characterized in that, In step 2, the external heat flow prediction model adjusts the duty cycle of the heating zone in advance at the location where a significant change in the external heat flow is predicted.

4. A thermal control method for improving the performance of a lunar orbit laser corner reflector according to claim 1, characterized in that, The proportional adjustment amount , The proportional gain determines the controller's responsiveness to the current deviation; the integral part... = , The integral coefficients are used to eliminate the steady-state error of the system; the differential part... = , represents the differential coefficient, used to predict the trend of deviation; e represents the deviation between the desired operating temperature of the corner reflector and the current temperature of the corner reflector as monitored in real time by the temperature sensor.

5. A thermal control method for improving the performance of a lunar orbit laser corner reflector according to claim 2, characterized in that, The corner reflector is covered with a thermally controlled multilayer and an OSR reflective surface, and a light shield is installed on the front side of the corner reflector. The corner reflector is made of solid glass.

6. A thermal control method for improving the performance of a lunar orbit laser corner reflector according to claim 2, characterized in that, The heating band includes multiple heating elements, each with an irregular shape that fits perfectly against the surface of the corner reflector.

7. A thermal control method for improving the performance of a lunar orbit laser corner reflector according to claim 6, characterized in that, The edges of the heating band are serrated, and the serrated edges of adjacent heating bands completely match.

8. A thermal control device for improving the performance of a lunar orbit laser corner reflector, applied to the thermal control method for improving the performance of a lunar orbit laser corner reflector as described in any one of claims 1-7, characterized in that, The device includes: The temperature measurement module is used to divide the corner reflector into multiple temperature measurement zones, each of which includes a temperature sensor; An active temperature control module is used to independently and actively control multiple temperature measurement zones. Each temperature measurement zone includes an independently controlled irregularly shaped heating belt. The heating belt is connected to a PID controller, which adjusts the duty cycle of the heating belt to achieve precise temperature control in each zone based on data from the temperature measurement module and an external heat flow prediction model. The passive temperature control module is used to set up a thermal control multilayer, OSR reflective surface and sunshade on the outside of the corner reflector that are adapted to the thermal characteristics of the solid glass corner reflector, so as to achieve heat insulation and reflection of solar radiation and reduce the impact of heat conduction on glass deformation. The control module is used to combine satellite orbital attitude data and external heat flow prediction model to dynamically adjust the external heat flow correction term of the PID controller, and coordinate the active and passive temperature control modules to ensure that the overall temperature and temperature gradient of the corner reflector meet the index requirements.

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