Satellite autonomous temperature control heating system based on orbit information

Abstract

The invention discloses a satellite autonomous temperature control heating system based on orbit information, and belongs to the technical field of satellite thermal control. The system comprises a heating execution unit, a local control unit, a storage unit and an initial state interface. Satellite orbit information and associated heating strategies are pre-stored in the storage unit. And after receiving the initial state information, the local control unit obtains a corresponding heating strategy from the storage unit according to the current time and the track information and autonomously controls the heating execution unit to work, and real-time temperature sensor feedback is not needed in the whole process. The invention further discloses a corresponding control method. According to the system and the method, a temperature sensor and related circuits are omitted, the system structure is simplified, occupation of satellite-borne main controller resources is reduced, light weight, low power consumption and high autonomy are achieved, and the system and the method are particularly suitable for microsatellites. And the heating unit and the control unit can be integrated on the flexible substrate, so that the integration level and the space adaptability are improved.

Description

Technical Field

[0001] The present invention relates to the field of satellite technology. Specifically, it relates to a satellite thermal control technology, and in particular, to a satellite autonomous temperature control and heating system based on orbital information. Background Art

[0002] During the on-orbit operation of a satellite, an accurate thermal control system is required to ensure that its internal equipment operates normally within an appropriate temperature range. Currently, satellite thermal control technologies are mainly divided into two categories: passive thermal control and active thermal control. Passive thermal control achieves temperature regulation through special material and structure designs without external energy input and is usually used as an auxiliary means. Active thermal control relies on external energy input or dynamic regulation mechanisms to achieve more precise temperature control. Common technologies include electric heating and refrigeration systems, fluid loops and phase change energy storage, loop heat pipes and radiators, etc.

[0003] In active thermal control, electric heaters are a commonly used means. Traditional electric heating control methods generally include the following steps: Temperature acquisition: Use thermistors (such as PT100, PT1000, MF51, MF501, and MF61, etc.) or other temperature sensors to continuously monitor the temperature of the object to be controlled. The temperature change causes the resistance value or other electrical signal parameters of the sensor to change.

[0004] Signal processing and transmission: After the sensor signal is processed, it is transmitted through a wire to the satellite's on-board computer (OBC) or a dedicated thermal control unit.

[0005] Control decision-making: The on-board computer receives the temperature data, compares it with the preset target temperature, and calculates the required heating power through control algorithms such as PID (Proportional-Integral-Derivative).

[0006] Execute heating: The on-board computer sends an instruction to the electric heater to adjust its heating power. Ground remote control is sometimes used as an auxiliary control means.

[0007] The structure of a commonly used thin-film electric heater for spacecraft is usually: two layers of polyimide film on the top and bottom, and the middle layer is an electrothermal metal wire formed by processes such as metal foil etching. Wires are welded to the metal wire and led out for power supply and connection.

[0008] However, for microsatellites / nanosatellites with extremely limited volume, weight, power consumption, and computing resources, the above traditional active thermal control methods have significant drawbacks: (1) High system complexity: It requires temperature sensors, signal conditioning circuits, connecting wires, and complex control logic in the on-board computer, increasing the complexity of system design, integration, and testing.

[0009] (2) High resource consumption: The temperature sensors and a large number of wires increase the volume and weight of the system; the real-time temperature acquisition and the operation of algorithms such as PID consume valuable computing resources (computing power) and power of the on-board controller.

[0010] (3) Poor adaptability and portability: The complex wiring and discrete components are not conducive to flexible deployment in the extremely compact space of microsatellites.

[0011] Therefore, there is an urgent need for a new heating control technology that is simpler, lightweight, low-power, and suitable for microsatellites. Summary of the Invention

[0012] The present invention aims to overcome the deficiencies of the prior art and provides an autonomous temperature control heating system and its control method for microsatellites, which has a simple structure, is lightweight, low-power, has a concise control circuit, does not require real-time temperature sensor feedback, does not rely on or reduces the reliance on the computing power of the on-board main controller, and is particularly suitable for microsatellites.

[0013] To solve the above technical problems, the present invention provides a satellite autonomous temperature control heating system based on orbit information, including: Heating execution unit: used to generate heat and heat satellite components; Local control unit: integrated or closely coupled with the heating execution unit, and used to control the working state of the heating execution unit according to a preset logic; Storage unit: connected to the local control unit, and pre-stores the orbit information of the satellite and the heating strategy data associated with the orbit information internally; Initial state interface: used to receive the initial state information of the satellite (for example, initial position, time, attitude, etc.).

[0014] It is characterized in that the local control unit is configured to: Receive the initial state information of the satellite through the initial state interface; Based on the received initial state information and the current time (or the time deduced from the initial state), query or calculate the preset heating strategy data corresponding to the current orbit position or stage from the storage unit; Autonomously determine the target heating power or working mode of the heating execution unit according to the preset heating strategy data; Control the heating execution unit to operate according to the determined target heating power or working mode to achieve temperature regulation.

[0015] Crucially, when the local control unit executes the above heating control process, it does not need to receive feedback signals from external real-time temperature sensors, and can run its core control logic independently of the satellite main on-board controller.

[0016] In a preferred embodiment, the heating execution unit and the local control unit (including its necessary circuits) are formed on a flexible substrate through an integrated manufacturing process (e.g., flexible circuit board etching) to constitute an integrated flexible heating control module.

[0017] In a preferred embodiment, the orbital information stored in the storage unit includes data or its model parameters that change over time, such as the position, velocity, attitude, and illumination conditions (entering / leaving the shadow area) of the satellite within one or more orbital periods.

[0018] In a preferred embodiment, the heating strategy data stored in the storage unit includes control parameters such as preset heating power levels, heating start / stop times, or duty cycles corresponding to different orbital positions, orbital phases, or illumination conditions. These strategy data are obtained through pre-ground simulation calculations based on the satellite thermal model, expected external heat flux changes, and target temperature requirements.

[0019] In a preferred embodiment, the local control unit includes a microcontroller (MCU) or an application-specific integrated circuit (ASIC) for executing control logic and data query / calculation.

[0020] In a preferred embodiment, the initial state interface can receive initial state information once or a limited number of times from the on-board main controller or other specified sources in a wired or wireless manner after satellite deployment or at a specific time point.

[0021] The present invention also provides a satellite autonomous temperature control heating control method based on orbital information, which is applied to the above system. The method includes the following steps: a) Initialization: Receive the initial state information of the satellite (such as initial position, time, etc.) through the initial state interface at a predetermined time point or condition; b) State determination: The local control unit determines the current orbital position or the orbital phase of the satellite according to the received initial state information and the internal clock (or time calculation); c) Strategy query / calculation: The local control unit accesses the storage unit and queries or calculates the corresponding preset heating strategy data (such as target heating power, start / stop instructions, etc.) according to the current orbital position or phase; d) Heating control: The local control unit autonomously generates a control signal based on the obtained heating strategy data to drive the heating execution unit to work according to the specified strategy; e) Loop / update: As time goes by, the local control unit periodically repeats steps b) to d) to dynamically adjust the heating strategy according to the satellite's operation in orbit.

[0022] Crucially, the execution of steps c) and d) of the method does not depend on real-time temperature measurement feedback.

[0023] Compared with the prior art, the present invention has the following remarkable beneficial effects: Simplify the system and reduce complexity: Without the temperature sensor and its related signal conditioning and transmission lines, the hardware composition and circuit complexity of the thermal control system are greatly simplified.

[0024] Save resources and achieve lightweight: The sensor and part of the cables are eliminated, which helps to achieve the lightweight of the satellite system; The heating execution unit and the local control circuit are integrally manufactured (such as flexible etching), with a compact structure and space saving, especially suitable for microsatellites where space is extremely precious.

[0025] Reduce power consumption and computing burden: The control logic is executed in the local control unit, without or greatly reducing the occupancy of the computing power of the satellite's main on-board controller, reducing the power consumption and computing load of the main controller, and improving the efficiency of processing other key tasks. The local control unit itself can also be designed to operate with low power consumption.

[0026] Improve autonomy and efficiency: Based on the pre-computed orbit information for feed-forward control, the autonomous operation of the heater is realized, reducing the dependence on ground commands or complex closed-loop control, and improving the real-time performance of the control response (compared with the centralized control relying on the main controller).

[0027] Optimize the production process: The heater part and the flexible control circuit are integrally etched and formed, simplifying the production and assembly processes and shortening the production cycle.

[0028] Enhance adaptability: Adopting the integrated design with a flexible substrate, it is easier to install in the narrow or irregular space inside the satellite. Description of the Drawings

[0029] Figure 1 It is the overall block diagram of the system.

[0030] Figure 2 It is the satellite orbit calculation flowchart. Detailed Embodiments

[0031] To make the objectives, technical solutions and advantages of the present invention clearer, the present invention will be described in detail below with reference to specific embodiments. It should be noted that, without conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

[0032] Embodiment 1: Integrated Heating Control Module Based on Flexible Circuit Board This embodiment provides an integrated autonomous temperature control heating module. The whole module is fabricated on a flexible polyimide (PI) substrate.

[0033] Heating execution unit: On one or more layers of the PI substrate, electrothermal lines with a predetermined shape and resistance value are formed through a metal foil (such as constantan, nichrome) etching process.

[0034] Local control unit: In another area or layer of the same PI substrate, a low-power microcontroller (MCU) chip, a non-volatile memory chip (such as Flash Memory), and necessary power management and interface circuits are integrated. The MCU, memory, and peripheral components can be fixed on the flexible substrate through SMT (Surface Mount Technology) or other micro-assembly technologies.

[0035] Storage unit: That is, the above-mentioned non-volatile memory chip. Before satellite launch or in the initial stage in orbit, the calculated orbit data and the corresponding heating power table (LookupTable, LUT) or heating control algorithm parameters are written into this memory through a specific interface. The orbit data may include key nodes in the next few days or several orbital periods (such as the time to enter / leave the shadow area, the time to cross a specific latitude / longitude, etc.) and the corresponding external heat flux prediction. The heating power table defines the power values that the MCU should output to the heating lines under different orbital segments or conditions (for example, controlled by the PWM duty cycle).

[0036] Initial state interface: It can be a simple serial communication interface (such as UART, SPI, or I2C), or several specific GPIO pins. After the satellite separates from the launch vehicle or receives the first ground command, the on-board main controller can send the current precise time, six orbital elements (or other forms of position / velocity vectors), and other initial state information to this module through this interface.

[0037] Integrated manufacturing: The wiring of the heating lines and the control circuit is formed in one step on the flexible PI substrate through the etching process, achieving a high degree of integration of the heating function and the control function.

[0038] Workflow: After the module is powered on, the MCU enters the standby state.

[0039] After receiving the initial state information through the initial state interface, the MCU stores it and starts a timer internally or uses the internal real-time clock (if available).

[0040] Based on the current time and the initial orbit information, the MCU calculates the current position of the satellite in orbit or the stage it is in (for example, whether it is in the sunlit area or the shadow area, how long until the next entry / exit from the shadow area, etc.).

[0041] Using this orbit position / stage information as an index, the MCU looks up the corresponding preset heating power value or start / stop instruction in the storage unit.

[0042] The MCU controls the drive circuit (such as a MOSFET switch) to apply voltage to the heating wire in PWM or other ways to generate the target power queried.

[0043] The MCU continuously updates the judgment of the satellite orbit position / stage over time, and periodically queries and adjusts the heating power to achieve open-loop temperature control based on orbit prediction. The entire process does not require real-time data from an external temperature sensor.

[0044] Embodiment 2: Control Method This embodiment describes the control method executed by the MCU in Embodiment 1: Initialization stage: The MCU waits to receive data through the initial state interface. Once valid initial time T0 and initial orbit parameters P0 are received, these information are recorded and the internal timer (or synchronize the internal clock) is started.

[0045] Orbit position / stage judgment: A simplified orbit dynamics model or a look-up table program runs inside the MCU. According to T0, P0 and the current time T_current (obtained from the internal timer), the current orbit state S_current (such as: whether in the shadow area, the expected remaining shadow area time, the current latitude range, etc.) is calculated or looked up.

[0046] Heating strategy query: The MCU uses S_current as an index to look up the corresponding heating power setting value Power_target or control mode Mode_target (such as: full-power heating, half-power heating, turn off heating, heating with a specific duty cycle, etc.) in the heating strategy database pre-stored in the storage unit (which can be a look-up table or a set of rules). This database is generated in advance based on detailed thermal analysis and orbit simulation.

[0047] Heating execution: The MCU controls its output port (such as the PWM output pin) to generate a corresponding drive signal according to Power_target or Mode_target, and applies it to the heating execution unit through the power switch circuit.

[0048] Periodic update: The MCU repeats steps 2 to 4 at a preset time step (such as every dozens of seconds or minutes), and continuously adjusts the heating output according to the progress of the satellite in orbit.

[0049] Key advantages are reflected: Sensorless: This method is completely independent of any real-time temperature feedback.

[0050] Autonomy: Once initialized, the MCU can operate independently without continuous intervention from the on-board main controller. The main controller only needs to communicate with the module when it is necessary to update the orbit model or strategy (if on-orbit update is supported in the design).

[0051] Controllable computational load: The computational load required for orbit position determination and look-up table operations is much smaller than that for real-time PID control and sensor data processing. Therefore, a low-power and low-cost MCU model can be selected.

[0052] Other considerations: Robustness: Multiple sets of orbit models or heating strategies can be backed up in the storage unit to cope with orbit perturbations or initial state errors. Simple fault detection logic can also be designed, such as detecting whether the heater current is abnormal.

[0053] Hybrid mode: In some applications with extremely high requirements, the system of the present invention can be used as a basic heating system, supplemented by a simple, threshold-triggered high / low temperature protection sensor and logic, without performing precise PID regulation, thus still maintaining the advantage of system complexity.

[0054] Communication method: Although cable-free is preferred, when the anti-interference requirement is extremely high, the initial state information and possible strategy updates can also be transmitted through a well-shielded cable.

[0055] In summary, through the combination of software and hardware, this embodiment utilizes pre-computed orbit information and corresponding heating strategies to achieve autonomous temperature control of the satellite heater without relying on real-time temperature sensors and complex on-board controller PID operations. This method is particularly suitable for small satellite platforms with strict restrictions on weight, power consumption, volume, and cost, and has significant practical value and innovation.

[0056] Embodiment 3: Control Strategy Based on Parameterized Orbit Model and Thermal Model Different from using a look-up table (LUT) to store the heating strategy in Embodiment 1, the storage unit in this embodiment stores the correlation coefficients and boundary conditions of the parameterized model.

[0057] Stored content: (1) Simplified orbit model parameters: For example, store the parameter set required for calculating the satellite position, velocity, and determining the illuminated / shaded area using a simplified orbit propagation model (such as a simplified version of the SGP4 model or a periodic function fitting for a specific orbit type). These parameters can be obtained by ground fitting based on precise ephemeris.

[0058] (2) Simplified thermal model parameters: Store the key parameters of a simplified thermal model (e.g., a first-order or second-order thermal network model) that describes the thermal characteristics of the heated component, such as heat capacity, thermal conductivity, radiation / absorption coefficients for the external environment, etc.

[0059] (3) Control law parameters: Store the control law parameters used to calculate the heating power based on the predicted temperature and the target temperature (a simplified feedforward control law or a correction rule based on the predicted deviation, but not real-time temperature feedback PID).

[0060] Tasks of the local control unit (MCU): 1. Receive the initial state information (T0, P0).

[0061] 2. Use the stored orbit model parameters and the current time T_current to calculate in real time the current orbit position, attitude, and external heat flux conditions (solar radiation, earth albedo / infrared radiation, etc.).

[0062] 3. Take the calculated external heat flux as the input, and use the stored thermal model parameters to predict the temperature change trend T_predicted of the controlled component within a specific time period (e.g., the next few minutes or one control cycle) if no heating is performed or heating is performed at a certain base power.

[0063] 4. Compare the predicted temperature T_predicted with the target temperature range T_target stored locally (which may also vary with the orbit).

[0064] 5. According to the comparison result and the stored control law parameters, calculate the heating power Power_calculated that needs to be applied to keep the future temperature within the T_target range as much as possible.

[0065] 6. Control the heating execution unit to output Power_calculated.

[0066] 7. Periodically repeat steps 2 - 6.

[0067] Advantages: Compared with the LUT, this method may require less storage space (storing parameters instead of a large number of data points), and theoretically has better adaptability to small changes in the orbit or environment (through model calculation instead of looking up a table).

[0068] Challenges: The MCU needs to have a certain computing power to execute the model calculation; the degree of simplification and accuracy of the model need to be carefully balanced.

[0069] Example 4: Structural part of two working conditions After the satellite is launched, it enters the corresponding orbit. The satellite needs to go through two working conditions: the sunlit area and the shaded area. The heating power required in these two working conditions and the power situation during their alternation are different.

[0070] The electric heating sheet in the film-type electric heater is composed of lead wires, electrothermal metal lines (metal foil etching), and upper and lower polyimide films. During its production process, it needs to go through processes such as design, photoplotting, exposure, and plate making. In the design stage, the FPCB (flexible printed circuit board) is a circuit board composed of an insulating substrate and a conductive layer. When designing, the conductive layer of the FPCB (flexible printed circuit board) and the heating wire of the heating circuit are designed on the same negative film at the same time, and the etching work is carried out simultaneously. Welding holes for relevant chip soldering are punched on the upper insulating film, and the corresponding welding holes are aligned with the designed solder joints. After being integrally formed with the heating circuit, the corresponding components are chip soldered to achieve the lightweight integration of the heater and the control system. The overall system block diagram is as Figure 1 shown.

[0071] The corresponding track information, embedded program, etc. are input into the main control MCU (micro control chip) of the FPCB (flexible printed circuit board) after welding. During operation, after the power is input (satellite power supply), it enters the power management module to distribute the required current, voltage, etc. for each part. The on-board controller inputs the initial track information to the main control MCU (micro control chip) through the communication interface (using a Bluetooth module). Through the algorithm of the main control MCU, the PWM signal (pulse width modulation wave) of the output pin is calculated and output. The on-off of the electronic switch (MOS tube) is controlled by the high and low potentials of the output pulse signal to realize the start and stop of the heating circuit and achieve the purpose of temperature control.

[0072] Example 5: Working principle of two working conditions This example elaborates in detail the working principle of the satellite autonomous temperature control heating system under two typical working conditions (sunlit area and shaded area). The core lies in accurately calculating the satellite orbit position through the embedded programming module and adjusting the heating power accordingly. Refer to Figure 2 the satellite orbit calculation flowchart shown, and this process mainly relies on accurate orbit dynamics models and numerical integration methods: 1. Self-controlled heating sheet The main control MCU (micro control chip) communicates with the on-board controller through the communication interface (CAN Bluetooth module) to obtain initial information such as the current position, time, and attitude of the satellite. This process corresponds to Figure 2 the initial orbit parameter input stage in. Subsequently, the embedded programming module will execute Figure 2The complex calculation process shown predicts the future flight path, attitude, and time and space nodes of the satellite by numerically integrating the satellite's motion equation. Based on the flight path and time and space nodes, the environmental conditions (sunlit area or shadow area) are determined, and the required compensation power is calculated in real time according to the environmental conditions. The main control MCU (micro control chip) outputs a control signal to the electronic switch (MOS transistor) to complete the start and stop of the heating circuit, adjust the heating power, and autonomously achieve temperature control.

[0073] When the satellite is in the sunlit area, the heating power is low; when it is in the shadow area, the heating power is high. According to the algorithm, different heating powers are provided for different positions on the corresponding orbit to achieve the purpose of adaptive heating function.

[0074] 2. Embedded programming module Embedded programming is a program written for the embedded system on the heating sheet, aiming to calculate the satellite's orbital position in space and is written in C language or assembly language. This module is responsible for implementing Figure 2 the orbital prediction algorithm shown. By analyzing the spatial position relationship between the satellite and the earth, the state quantity is output, thereby controlling the heating power of the heating sheet to achieve the function of automatic control. The advantages for specific hardware are high integration, low power consumption, and real-time processing.

[0075] In satellite orbit prediction, the input parameters are the initial orbit parameters of the satellite, and this system uses the general two-line element set TLE as the initial condition. After obtaining the initial orbit parameters, referring to Figure 2 the embedded module performs precise orbit prediction calculations. This calculation first requires precise time and coordinate system conversions, which involve the calculation of Greenwich Mean Sidereal Time (GMST), precession, nutation, and polar motion to determine the transformation matrix W from the geocentric inertial system to the geocentric fixed system or other required coordinate systems.

[0076] At the same time, as Figure 2 shown, it is necessary to calculate the precise positions of the sun and the moon (calculate the positions of the sun and the moon) because they are the main sources of gravitational perturbation and solar radiation pressure perturbation. Based on the current state of the satellite (position, velocity), the positions of the sun and the moon, and the coordinate transformation relationship, it is necessary to calculate the accelerations generated by various forces acting on the satellite. Among them, is the initial acceleration vector, is the earth's gravitational acceleration vector, is the solar radiation acceleration vector. The GMST calculation is to calculate the Greenwich Mean Sidereal Time, which is the key time parameter for astronomical coordinate system transformation. The precession calculation is to calculate the slow precession (drift) of the Earth's axis of rotation due to long-term gravitational effects, which is used to correct the coordinate system. The nutation calculation is to calculate the short-term periodic oscillation of the Earth's axis of rotation due to factors such as the gravitational forces of the sun and moon, which is used to correct the coordinate system. The polar motion calculation is to calculate the small movement of the Earth's rotation pole relative to the Earth's crust surface, which is used for the precise transformation of the geocentric inertial coordinate system. Calculating the coordinate transformation matrix W is to calculate the matrix used for transformation between different astronomical coordinate systems based on the results of the above GMST, precession, nutation, and polar motion. Calculating the positions of the sun and moon is to calculate the precise position vectors of the sun and moon at a specific moment in a certain reference coordinate system (usually the geocentric inertial system), which is the basis for calculating gravitational perturbations and solar radiation pressure perturbations. Calculating the initial values of the Runge-Kutta method integral is to use the Runge-Kutta numerical integration method to provide the state vectors (position and velocity) at several consecutive time points required for the subsequent multi-step integration method (such as the Adams-Cowell method). The Adams-Cowell integration is to use the Adams-Cowell linear multi-step numerical integration method to integrate the satellite's motion differential equation according to the calculated total acceleration to predict the future orbital state. Orbit prediction refers to the sequence of the satellite's positions and velocities in the future period obtained by using the above integration method.

[0077] The Two-Line Element Set (TLE) is a standardized data format used to describe the orbital parameters of artificial satellites and is widely used in satellite orbit prediction and tracking. The TLE consists of two lines, each with 69 characters, containing the satellite's orbital information, which is defined as follows: The first line: Line number: The first character, usually "1".

[0078] Satellite number: The 3rd - 7th characters, NORAD number.

[0079] Classification: The 8th character, usually "U" (unclassified).

[0080] International number: The 10th - 17th characters, launch year and number.

[0081] Epoch time: The 19th - 32nd characters, the UTC time corresponding to the data.

[0082] First derivative of the mean motion: The 34th - 43rd characters, the orbital change rate.

[0083] Second derivative of the mean motion: The 45th - 52nd characters, the orbital change acceleration.

[0084] BSTAR drag coefficient: Characters 54 - 61, influence of atmospheric drag.

[0085] Orbit model: Character 63, usually "0".

[0086] Element set number: Characters 65 - 68, TLE release sequence number.

[0087] Checksum: Character 69, used to verify data integrity.

[0088] Second line Line number: Character 1, usually "2".

[0089] Satellite number: Characters 3 - 7, NORAD number.

[0090] Orbit inclination: Characters 9 - 16, angle between the orbital plane and the equatorial plane.

[0091] Right ascension of the ascending node: Characters 18 - 25, angle between the ascending node and the vernal equinox.

[0092] Eccentricity: Characters 27 - 33, shape of the orbital ellipse.

[0093] Argument of perigee: Characters 35 - 42, angle between the perigee and the ascending node.

[0094] Mean anomaly: Characters 44 - 51, position of the satellite in the orbit.

[0095] Mean motion: Characters 53 - 63, number of orbits the satellite makes around the Earth per day.

[0096] Number of orbital revolutions: Characters 64 - 68, total number of revolutions since launch.

[0097] Checksum: Character 69, used to verify data integrity.

[0098] According to Figure 2 the shown process, after obtaining the initial orbit parameters, enter the orbit extrapolation and solution stage. Use numerical integration methods to simulate the change of the orbit over time. Numerically integrate the satellite motion equations with a set of correct initial values to extrapolate the future satellite orbit. When the satellite motion force model is relatively complete, the accuracy of the initial values will directly affect the accuracy of the extrapolated orbit. During the calculation process, due to the influence of the initial value error, the longer the calculation interval, the greater the accumulated error of the integration. The orbit calculation steps are as Figure 2 shown.

[0099] In actual positioning calculations, in order to obtain the precise ephemeris coordinates at a specific time, interpolation processing may be required. This corresponds to Figure 2For example, accurate ephemeris coordinates with an interval of 1 second or even smaller step size are required. Based on the accuracy and low computational cost, the Newton polynomial interpolation method of the mean difference of data is used, assuming that Control Points , defined in The zero-order mean difference at ,exist The first-order mean difference at is defined as , the k-order mean difference is defined as:

[0100] Then the Newton interpolation polynomial can be expressed as:

[0101] Each level consists of 2 additions and 1 multiplication, and the time consumption is: Compared with the classical Lagrange polynomial interpolation, Newton polynomial interpolation is much more efficient. Given Different points and the corresponding mean difference coefficient , for any time The interpolation polynomial is generated by the following iteration (Horner algorithm). Where n represents the number of known control points. A is the addition result. M is the multiplication result. k is the order of the mean difference.

[0102]

[0103] The accuracy and time consumption of the above algorithm are within an acceptable range, and the mean differences of each order can be pre-calculated and stored, and can be directly called when needed.

[0104] Satellite orbit data is predicted by double row elements. Figure 2 In the process, after orbit calculation, it enters the state judgment and output stage. When the actual satellite mission is executed, the satellite position can be obtained in real time by injecting the mission start time. According to the relationship between the sun and the earth and the satellite position, it can output whether the satellite is in the sunlit area (output value is 1) or the shadow area (output value is 0), and the remaining time in the area. These output information will be used as Figure 2 The final result of the process is used to guide the main control MCU (micro control chip) of the integrated heater to achieve the heating power change of the electric heater. In order to reduce the control error, the main control MCU (micro control chip) performs position calibration with the onboard controller after running for a certain period of time. This corresponds to Figure 2 The process may include track calibration and correction steps to ensure long-term operation accuracy.

[0105] Example 6: Distributed multi-zone autonomous heating system For satellite components with complex structures or large differences in heat requirements, a distributed system can be formed by using multiple self-controlled temperature heating modules of the present invention.

[0106] System composition: N independent self-controlled temperature heating modules are deployed on the satellite (each module has a structure similar to that of Embodiment 1 or 3). Each module is responsible for heating a specific area or component.

[0107] Data storage: In the storage unit of each module, heating strategies affected by orbital information related to its responsible area are stored. For example, for devices on both sides of the satellite, their illumination conditions are different at the same orbital position, so the heating strategies stored in the modules on both sides will also be different.

[0108] Initialization: All modules can share the same initial state interface or receive initial state information separately. It is necessary to ensure the synchronization of their time bases.

[0109] Coordination (optional): No coordination: Each module works completely independently.

[0110] Simple coordination: Each module can perform very limited information interaction through a simple bus (such as CAN or RS485), such as broadcasting a time synchronization signal, or notifying other modules to enter the safe mode when a certain module detects a global anomaly (such as under-voltage of the power supply). However, complex real-time temperature information sharing and centralized control are avoided.

[0111] Advantages: Good scalability, enabling fine-grained management of large or complex thermal structures by partitioning, while maintaining the simplicity and autonomy of individual modules. Good fault isolation, the failure of one module does not affect the operation of other modules.

[0112] Challenges: It is necessary to manage the strategy generation and loading of multiple modules; if coordination is required, it will increase a certain amount of communication overhead and complexity.

[0113] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A satellite autonomous temperature control and heating system based on orbital information, characterized in that: include: A heating execution unit, used for heating satellite components; A local control unit coupled to the heating execution unit; A storage unit, connected to the local control unit, pre-stored with orbit information of the satellite and heating strategy data associated with the orbit information; An initial state interface is used to receive the initial state information of the satellite; wherein the local control unit is configured to: based on the received initial state information and internal time information, obtain the preset heating strategy data corresponding to the current orbital state from the storage unit, and autonomously determine and control the working state of the heating execution unit according to the heating strategy data to achieve temperature regulation; and the local control unit does not rely on the feedback signal from the external real-time temperature sensor during the execution of heating control.

2. The system according to claim 1, characterized in that The heating execution unit and the local control unit are integrated and manufactured on the same flexible substrate.

3. The system according to claim 2, characterized in that The heating execution unit and the related circuits of the local control unit are formed by performing an etching process on the flexible substrate.

4. The system according to claim 1, characterized in that The orbit information stored in the storage unit includes data or model parameters of the satellite's position, speed, attitude or illumination conditions changing over time in one or more orbital periods.

5. The system according to claim 1, characterized in that The heating strategy data stored in the storage unit includes preset heating power levels, heating start and stop times or duty cycle parameters corresponding to different orbital positions, orbital stages or lighting conditions.

6. The system according to claim 1, characterized in that The heating strategy data is calculated through ground pre-simulation based on the satellite thermal model, expected external heat flux changes and target temperature requirements.

7. The system according to claim 1, characterized in that The local control unit includes a microcontroller unit (MCU) or an application specific integrated circuit (ASIC).

8. The system according to claim 1, characterized in that The initial state information includes the initial position, initial time, initial speed or orbital elements of the satellite.

9. A satellite autonomous temperature control and heating control method based on orbit information, applied to the system according to any one of claims 1 to 8, characterized in that: The method comprises the following steps: a) enabling the local control unit to receive initial state information of the satellite through the initial state interface; b) the local control unit determines the current orbital state of the satellite based on the received initial state information and internal time information; c) the local control unit accesses the storage unit to query or calculate corresponding preset heating strategy data according to the current track state; d) the local control unit autonomously generates a control signal based on the acquired heating strategy data to drive the heating execution unit to work according to the specified strategy; The execution of steps c) and d) does not depend on the real-time feedback of the temperature measurement value.

10. The method according to claim 9, characterized in that Steps b) to d) are repeatedly executed periodically to dynamically adjust the heating strategy according to the operation of the satellite in orbit.

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