A CubeSat release status dual-redundant autonomous monitoring system and method

Abstract

The application provides a kind of cubical star release state double redundancy autonomous monitoring system and method, it is related to spacecraft release technical field.The cubical star release state double redundancy autonomous monitoring system, including cubical star release unit, short message communication antenna, short message communication module, impedance monitoring unit, two or more travel switches, signal acquisition and processing unit, data reporting unit.Through being provided with impedance monitoring and travel switch, by forming electromagnetic field near field perception and mechanical contact perception, and by fusing electromagnetic field near field perception and mechanical contact perception two different physical principles monitoring means, monitoring independent work, backup each other, the reliability that the failure of single channel does not affect overall judgment, fundamentally overcome the systematic risk of single technical solution.

Description

Technical Field

[0001] This invention relates to the field of spacecraft release technology, specifically to a dual-redundant autonomous monitoring system and method for the release status of a CubeSat. Background Technology

[0002] With the rapid development of microsatellite technology, CubeSats, as a standardized microsatellite platform, have been widely used in technology verification, scientific exploration, and commercial services. CubeSats are typically launched into orbit in batches from platforms such as launch vehicles and space stations using standardized release mechanisms (hereinafter referred to as "releasers"). Currently, most mainstream CubeSat release mechanisms employ a spring-loaded pushrod mechanical design, with the core principle being the reliable unlocking and ejection of the satellite from the cavity. However, existing technology suffers from a long-overlooked and potentially cascading failure flaw: the "open-loop execution" of the release action and the "unknowable state" of the release result. Specifically, existing release devices can only receive the "release" command and execute the mechanical action, but cannot directly and in real-time perceive the final result—whether the satellite has physically disengaged. Ground control centers can only indirectly infer the success of the release through telemetry data (such as confirmation of the unlock command) or passively wait for radio signals emitted after the CubeSat enters orbit to deduce whether the release was successful.

[0003] In existing technologies, some solutions attempt to use limit switches as a means of separation sensing. However, limit switches have the following inherent drawbacks: First, limit switches are mechanical contact components, which are susceptible to physical failures such as contact jamming, wear, and cable breakage. Second, existing limit switches can only provide binary (0 / 1) transition signals, which can only confirm whether the satellite has detached from the ejection component, but cannot sense the intermediate state of the satellite during the ejection process, such as when it is stuck in the middle of the cavity. Third, the installation of limit switches requires contact with the satellite's mechanical interface, which poses a risk of unintended interference to the standardized CubeSat, and there is no corresponding risk mitigation method. In addition, in the existing technology, the invention patent with application number 202511876593.2 discloses a method and related equipment for on-orbit release and imaging observation of a satellite, which uses the observation camera carried by the main satellite to confirm the release status of the satellite. However, this is essentially a post-event observation scheme, which not only requires additional payload resources of the main satellite, but also cannot complete the status judgment at the moment of release, and cannot provide a basis for real-time mission decision-making. Therefore, there is an urgent need for a solution that can integrate multiple physical principles, achieve redundancy and complementarity, and empower the release mechanism with the ability to autonomously, directly, and in real time monitor the release results without changing the standard design of the CubeSat. Summary of the Invention

[0004] (a) Technical problems to be solved To address the shortcomings of existing technologies, this invention provides a dual-redundant autonomous monitoring system and method for CubeSat release status. It deeply integrates non-contact sensing based on antenna near-field impedance monitoring with contact physical triggering based on limit switches to form a redundant monitoring architecture with dual physical principles and dual independent channels. By utilizing existing short message communication antennas, it solves the problems of physical failure risk of single limit switches and inability to sense the intermediate state of the satellite during the ejection process.

[0005] (II) Technical Solution To achieve the above objectives, the present invention is implemented through the following technical solution: a dual-redundant autonomous monitoring system for CubeSat release status, comprising: a CubeSat release unit, a short message communication antenna, a short message communication module, an impedance monitoring unit, two or more limit switches, a signal acquisition and processing unit, and a data reporting unit; The cubestar release unit has a cavity for containing a cubestar and an ejection mechanism for ejecting the cubestar out of the cavity. The short message communication antenna is installed on the CubeSat release unit, and its near-field radiation region covers the space where the CubeSat is located inside the cavity. The short message communication module is electrically connected to the short message communication antenna and is used to interact with an external communication system. The impedance monitoring unit is electrically connected to the short message communication antenna and is used to transmit detection signals and measure the input impedance or reflection coefficient of the short message communication antenna. The two or more limit switches are installed at the contact surface between the cubestar release unit and the cubestar, and their contact state changes with the presence or absence of the cubestar, forming a mechanical contact sensing. The signal acquisition and processing unit is electrically connected to the impedance monitoring unit and the limit switch, respectively, and is used to acquire impedance monitoring data and limit switch status, and perform fusion judgment. The data reporting unit is connected to the signal acquisition and processing unit and the short message communication module, and is used to send the fusion judgment result to the ground control center through the short message communication module.

[0006] Preferably, the main body of the cubestar release unit adopts a standard cubestar size for the release device structure design, has a rectangular cavity to accommodate the cubestar, four guide rails inside the cavity, the cubestar is installed in contact with the guide rails, a compression spring is set at the bottom of the cavity as an ejection actuator, a release device control box is installed on the cover plate above the main body of the device, and a connector plug is provided on the side, which can be used to transfer the electrical interface of the release status monitoring system. All monitoring data and control commands are transmitted through this connector plug.

[0007] Preferably, the short message communication antenna is a microstrip patch antenna, installed on the inner surface of the top cover of the CubeSat release unit, with the antenna radiating surface facing the inside of the cavity, and its near-field radiation range covering the entire cavity space; the antenna operates at the BeiDou short message frequency, which can be reused as a sensing antenna for release status monitoring, without the need for additional dedicated monitoring antennas, and does not occupy additional space for the entire satellite installation.

[0008] Preferably, the short message communication module adopts an aerospace-grade Beidou short message communication module, which integrates a baseband processor, an RF transceiver, and a power amplifier. This module is installed in the side wall circuit box of the CubeSat release unit and is electrically connected to the short message communication antenna. It is used to interact with the external communication system after the release is completed, and can also work with the impedance monitoring unit to complete the transmission and reception of detection signals.

[0009] Preferably, the impedance monitoring unit is integrated into the short message communication module or set up independently, and is electrically connected to the short message communication antenna. It is used to transmit detection signals and measure the input impedance or reflection coefficient of the short message communication antenna. When the CubeSat is located in the cavity, the metal structure of the CubeSat body will change the medium distribution around the antenna, thereby causing the antenna input impedance to shift. When the CubeSat is ejected from the cavity, the medium around the antenna returns to free space, and the input impedance will undergo a significant observable change. By capturing this impedance change, it can be determined whether the CubeSat has left the cavity, thus forming a near-field electromagnetic field sensing.

[0010] Preferably, the two or more limit switches are installed at the contact surface between the cubestar release unit and the cubestar. Their contact states change depending on the presence or absence of the cubestar. When the cubestar is inside the cavity, the cubestar body presses against the limit switch contacts, putting the contacts in a first state. When the cubestar is ejected from the cavity, the contacts spring back, and the state switches to a second state. Each limit switch outputs a signal independently without interfering with each other. The failure of any single limit switch does not affect the state output of other limit switches.

[0011] Preferably, the signal acquisition and processing unit is electrically connected to the impedance monitoring unit and the limit switch, respectively, and is used to acquire impedance monitoring data and limit switch status, and perform fusion judgment.

[0012] Preferably, the data reporting unit is connected to the signal acquisition and processing unit and the short message communication module, and is used to send the fusion judgment result to the ground control center through the short message communication module.

[0013] Preferably, the impedance monitoring unit is integrated within the short message communication module or set up independently, and mainly includes: a directional coupler connected between the output of the RF power amplifier and the antenna feed point for coupling reflected signals; a power detector electrically connected to the directional coupler for measuring forward power Pf and reflected power Pr; and an analog-to-digital converter that converts the power detection results into digital signals. When the cubesat is in the cavity, the dielectric load will change the distribution of the antenna near field, thereby changing the input impedance and reflection coefficient of the antenna. When the cubesat is ejected from the cavity, the load environment of the antenna is restored, and the input impedance and reflection coefficient will undergo measurable and significant changes, thereby realizing non-contact cubesat presence status sensing.

[0014] Preferably, the short message communication module is installed in the side wall circuit box of the CubeSat release unit body. The short message communication module integrates a baseband processor, radio frequency transceiver and power amplifier, which can realize the reception and transmission of BeiDou short message signals. After the release mission is completed, the monitoring results are sent to the ground control center through the short message communication link. There is no need to build an additional dedicated communication channel, which reduces the complexity of the system and the resource occupancy rate.

[0015] The monitoring methods of the dual-redundant autonomous monitoring system for CubeSat release status include: Step S1: Reference Calibration Before the CubeSat is loaded into the release mechanism cavity and the release command is executed, the impedance monitoring unit emits a detection signal to measure the first input impedance Z1 of the short message communication antenna and stores it in the signal acquisition and processing unit; at the same time, it records the first state S1 of the limit switch.

[0016] Step S2: Release instruction execution The ejection actuator receives the release command and performs the ejection action.

[0017] Step S3: Real-time monitoring Within a preset time window after the release command is executed, perform the following parallel monitoring: The impedance monitoring unit continuously or intermittently measures the second input impedance Z2 of the short message communication antenna; The signal acquisition and processing unit monitors the state changes of the limit switch and obtains the second state S2; Step S4: State determination The signal acquisition and processing unit performs a fusion judgment based on four working conditions: normal release, limit switch failure, impedance monitoring false alarm, and release failure. Step S5: Result Reporting The data reporting unit sends the fusion judgment result to the ground control center through the short message communication module, and optionally includes the original impedance monitoring data and limit switch status data; The fusion judgment process is shown in the table below:

[0018] This table is a visual representation of the core judgment logic of this invention. Each of the four different working conditions corresponds to a clear judgment output, realizing the redundancy and complementarity of the two monitoring methods. Even when a single monitoring channel fails, it can still output valid results, greatly improving the reliability of the monitoring system.

[0019] (III) Beneficial Effects This invention provides a dual-redundant autonomous monitoring system and method for the release state of a CubeSat. This invention has the following beneficial effects: 1. This invention incorporates impedance monitoring and limit switches, forming a monitoring method based on electromagnetic field near-field sensing and mechanical contact sensing. By integrating these two completely different physical principles, and ensuring that these two monitoring methods operate independently and serve as backups for each other, the failure of a single channel does not affect the overall reliability of the judgment, fundamentally overcoming the systemic risks of a single technical solution. At the same time, the logical algorithm that integrates the data from the two monitoring methods can clearly distinguish four operating conditions: normal release, limit switch failure, impedance monitoring false alarm, and release failure. This provides irreplaceable first-hand data for on-orbit fault diagnosis and post-fault zeroing, improving the safety and practicality of equipment operation.

[0020] 2. This invention compensates for the risks of mechanical jamming and wear of limit switches by using the non-contact characteristics of impedance monitoring. At the same time, impedance monitoring can also sense continuous states and can detect fault modes that limit switches cannot detect, such as satellites being "stuck in the middle of the cavity". The two can complement each other. The mature stability of limit switches can also compensate for the drift risk that impedance monitoring may have in extreme environments. The binary hard signal provided by the limit switch is used as a reference for the calibration of the impedance monitoring threshold. Using the hard signal of the limit switch as a reference, the system can automatically calibrate the impedance monitoring threshold before each mission release, adapting to environmental factors such as different satellite shell materials and temperature changes, thereby overcoming their respective shortcomings.

[0021] 3. All sensing modules of this invention are located on the structure of the release unit. The sensing function is completed independently by the release mechanism. The monitoring is completed instantaneously within the millisecond to second time period of release, providing an immediate "stop / continue" decision basis for satellite deployment missions. At the same time, the impedance monitoring unit can reuse the short message communication antenna and part of the radio frequency front end. The impedance monitoring is completely non-contact, with only a small amount of additional detection circuitry. The limit switch is a mature and low-cost component that only contacts the CubeSat release unit. It is completely non-intrusive and does not interfere with the CubeSat structure. It achieves the dual-redundant "status visibility" function at extremely low additional cost, making it extremely cost-effective. No hardware or software changes are required for the standardized CubeSat, perfectly maintaining the integrity and universality of the standardized CubeSat. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the layout of each unit in the system of the present invention; Figure 2 This is a flowchart of the monitoring method of the present invention; Figure 3 This is the truth table for the double-redundant judgment logic of this invention; The components include: 1. Cubic star release unit; 2. Cavity; 3. Ejection actuator; 4. Guide rail; 5. Limit switch; 6. Short message communication antenna; 7. Release control box; 8. Release device; 9. Connector plug; 10. Short message communication module; 11. Signal acquisition and processing unit; and 12. Data reporting unit.

[0023] Figure 1 The structural diagram is only provided for the purpose of understanding the technical solution of the embodiment, and the dashed lines are the hidden internal outlines. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0025] Example 1: like Figure 1-3 As shown, this embodiment of the invention provides a dual-redundant autonomous monitoring system for the release status of a CubeSat, specifically including: The cubestar release unit 1 adopts a standard 2U cubestar releaser structure, with a rectangular cavity 2 to accommodate the cubestar. A compression spring is set at the bottom of the cavity 2 as an ejection actuator 3. The cubestar is installed in contact with the guide rail 4. A releaser control box 7 is installed on the cover plate above the mechanism body. There is a connector plug 9 on the side. A release device 8 is set at the outlet position to lock the cubestar to be released. After receiving the release command, the locking structure is opened to complete the unlocking, allowing the ejection actuator to eject the cubestar from the cavity.

[0026] The short message communication antenna 6 adopts the form of a microstrip patch antenna and is installed on the inner surface of the top cover plate of the CubeSat release unit 1. The antenna radiation surface faces the inside of the cavity 2, and its near-field radiation range covers the entire space of the CubeSat contained in the cavity 2. The antenna operates at the dedicated frequency of BeiDou short message communication.

[0027] The short message communication module 10 adopts an aerospace-grade Beidou short message communication module, with the optional model XX-BD2-S, integrating a baseband processor, RF transceiver, and power amplifier. This module is installed in the side-wall circuit box of the CubeSat release unit 1. It can provide a hardware multiplexing basis for the impedance monitoring unit while performing communication functions, eliminating the need for an additional dedicated RF path and further reducing the overall system complexity and additional resource consumption.

[0028] The impedance monitoring unit, integrated within the short message communication module 10, can be configured independently and includes: A directional coupler, connected between the output of the RF power amplifier and the antenna feed point, is used to couple reflected signals; A power detector, connected to a directional coupler, is used to measure forward power Pf and reflected power Pr; An analog-to-digital converter converts the power detection results into a digital signal.

[0029] The impedance monitoring unit can actively transmit independent detection signals, measure the reflection coefficient, calculate the voltage standing wave ratio, and characterize the change in antenna input impedance. This can effectively reflect whether a cubesat structure exists in the cavity. When the cubesat is completely located in the cavity, the metal or dielectric structure will change the electromagnetic field distribution in the near field of the antenna, causing the antenna input impedance to shift significantly compared to the cavity state. This shift can be accurately captured by the impedance monitoring unit, thereby achieving non-contact sensing of whether the cubesat is in place.

[0030] Limit switches 5, employing miniature waterproof microswitches, are installed on the satellite contact surfaces on both sides of the bottom of the release mechanism cavity 2. The switch contacts are normally closed: during satellite loading, the contacts are pressed open to form an open state; after satellite release, the contacts close to form a connected state. The two limit switches 5 are respectively installed inside the guide rail at the cavity outlet. When the CubeSat is fully in place, the CubeSat shell presses the contacts of the limit switches 5, placing them in a preset initial closed state. When the CubeSat moves outward and completely disengages from the contacts, the contacts automatically open, completing the state triggering. The signal lines of the two limit switches 5 are independent and connected to different input channels of the signal acquisition and processing unit 11, further enhancing the redundancy of the mechanical sensing components and avoiding monitoring risks caused by the failure of a single switch.

[0031] The signal acquisition and processing unit 11 is installed in the side-wall circuit box, and is connected to the analog-to-digital output terminal of the impedance monitoring unit and the signal lines of the two limit switches, respectively. It acquires data from both monitoring methods in real time and performs state judgment according to a preset fusion logic. Specifically, it can use an STM32 series aerospace-grade microcontroller, which communicates with the impedance monitoring unit via an SPI interface to obtain VSWR data and acquires the state of limit switch 5 via GPIO interrupt. The microcontroller internally contains a fusion judgment algorithm, including: Benchmark learning module: Before the release command, the VSWR value is sampled 10 times and averaged as the benchmark VSWR_ref; at the same time, the initial state of limit switch 5 is recorded; Real-time monitoring module: After the release command, continuously collect VSWR values ​​at a sampling rate of 100Hz, and simultaneously monitor the interruption of limit switch 5.

[0032] Threshold comparison module: When the change in the measured VSWR value relative to the reference value ΔVSWR > the preset threshold, such as when it is set to 15%, ΔVSWR > 15%, then it is determined that "the impedance monitoring channel has determined that the satellite has left its position".

[0033] Fusion Decision Module: Outputs the final result based on the aforementioned working condition judgment logic table.

[0034] The data reporting unit 12 reuses the short message communication module 10 to encode the fusion judgment result into the BeiDou short message format. The BeiDou short message format can include: releaser ID, timestamp, judgment result, original VSWR value, and limit switch 5 status. It is sent to the BeiDou satellite through the short message communication antenna 6, and then forwarded to the ground control center by the BeiDou satellite. The ground control center can directly obtain the real-time status result of this CubeSat release mission without relying on the data forwarding process of other equipment on the satellite, which shortens the information transmission link and further improves the reliability of status information.

[0035] Monitoring methods and procedures The monitoring method in this embodiment specifically includes the following steps: Step S1: System Initialization The ground sends a "prepare to release" command, which wakes up the signal acquisition and processing unit 11 and initiates the reference calibration process.

[0036] Step S2: Reference Calibration The microcontroller controls the impedance monitoring unit to continuously transmit low-power detection signals (-5dBm) 10 times, measures the VSWR value, removes the maximum and minimum values ​​and takes the average to obtain VSWR_ref = 2.1; at the same time, it reads the status of limit switch 5, S1 = [Channel 1: Open, Channel 2: Open].

[0037] Step S3: Release instruction execution The ground sends a "release" command, which activates ejection mechanism 3, releasing the compressed spring and propelling the CubeSat outward.

[0038] Step S4: Real-time monitoring and data collection The microcontroller starts a timer to collect the VSWR value at a frequency of 100Hz within 3 seconds after the release command, and enables interrupt detection of limit switch 5. The actual test found that the VSWR value jumped from 2.1 to 1.3 about 80ms after the release, and ΔVSWR=38% >15% threshold. At the same time, both limit switch 5 channels generated interrupts at about 15ms, and the state changed to closed.

[0039] Step S5: Fusion Judgment Based on the collected data, the impedance monitoring channel judged "satellite has left its position", and the limit switch 5 channel judged "triggered", which meets the working condition 1. The microcontroller outputs the fusion judgment result: "Release successful, dual channels consistent".

[0040] Step S6: Result Reporting Data reporting unit 12 encodes the result into a BeiDou short message, which includes: releaser ID = 01, timestamp = 2025-03-25 10:30:15.200, result = 0x01, VSWR_final = 1.3, and switch status = 0x03. The message is sent to the BeiDou satellite through the short message communication antenna 6. Among them, result = 0x01 means that the release was successful, and switch status = 0x03 means that both channels have been triggered.

[0041] Step S7: Abnormal operating condition simulation To verify the robustness of the system, during ground testing, a fault condition of limit switch 5 can be simulated: one signal line of limit switch 5 is manually disconnected; the above process is repeated, impedance monitoring is normal and the satellite is determined to be out of position, while only one channel of limit switch 5 is triggered; the combined judgment output condition 2: "Release successful, limit switch 5 single channel fault", and the fault information is reported.

[0042] The monitoring method effectively distinguishes different fault types, providing accurate information for ground mission decisions and verifying the effectiveness of the dual-redundancy fusion logic. This system leverages the complementary advantages of two different physical principle sensing methods, significantly improving the reliability of CubeSat release status monitoring with extremely low additional hardware costs. It avoids misjudgments caused by the failure of a single monitoring scheme and is suitable for batch deployment missions of various standardized CubeSats.

[0043] Example 2: This embodiment differs from Embodiment 1 in that the impedance monitoring unit does not use an independent detection signal transmission, but instead reuses the normal communication transmission signal of the short message communication module 10 for monitoring. Specifically, after the release command is executed, the short message communication module 10 sends a status report message according to a preset timing sequence. During message transmission, the impedance monitoring unit measures the reflected power in real time through a directional coupler. Since the message transmission power can reach 5W, which is relatively high, the signal-to-noise ratio of the reflected signal is higher, and the impedance change detection is more sensitive.

[0044] Based on this embodiment, the present invention provides a dual-redundant autonomous monitoring system for CubeSat release status, and its dual-redundant monitoring application in a mission to deploy 12 CubeSats in a single launch. Mission Background: A mission to launch 12 satellites in a single launch employed four separation and release surfaces, each carrying three 6U CubeSats. Each release surface integrated the aforementioned dual-redundant monitoring system.

[0045] The system is configured as follows, taking a single release surface as an example: Impedance monitoring channel: Multiplex short message communication antenna 6, and determine whether the satellite is in cavity 2 by monitoring the antenna standing wave ratio (VSWR). Specifically, the VSWR is higher when the satellite is in place and decreases when it is out of place.

[0046] Limit switch with 5 channels: Each group of satellites corresponds to a set of micro switches. The switch is open when the satellite is pressed and closed when it is released.

[0047] Fusion Judgment Unit: STM32 microcontroller, which acquires two signals and performs logical judgments.

[0048] Monitoring process: S1, Pre-release calibration After the satellite is loaded and positioned, the system measures the initial VSWR value and records that the state of limit switch 5 is "open".

[0049] S2, Execute Release The release surface controller issues an ejection command, and the spring pushes the satellite outward.

[0050] S3, Real-time Monitoring Impedance monitoring: VSWR changes are continuously monitored. After the satellite is removed, the VSWR drops to around 1.4, and the rate of change exceeds the preset threshold.

[0051] Limit switch 5: At the moment the satellite leaves its position, the switch contacts change from open to closed.

[0052] S4, Fusion Judgment

[0053] S5. Result Reporting Results: The system successfully identified a stuck limit switch 5 fault in a single ejection test, but still relied on the impedance monitoring channel to correctly determine the release success, thus avoiding false alarms.

[0054] The advantage of this embodiment is that it further simplifies the hardware, eliminates the need for independent detection signal transmission, and reduces power consumption. However, it is necessary to ensure that the satellite has left its position at the moment of message transmission; otherwise, high-power transmission may cause amplifier damage due to antenna mismatch. Therefore, this embodiment is suitable for timing scenarios where the satellite is released before reporting.

[0055] Working Principle: During operation, this invention compensates for the risks of mechanical jamming and wear of limit switch 5 through the non-contact characteristics of impedance monitoring. Impedance monitoring can also sense continuous states, detecting fault modes that limit switch 5 cannot detect, such as satellite "jammed in the middle of cavity 2," thus complementing each other's strengths. The mature stability of limit switch 5 can also compensate for the drift risk that impedance monitoring may have in extreme environments. Using the binary hard signal provided by limit switch 5 as a reference for impedance monitoring threshold calibration, the system can automatically calibrate the impedance monitoring threshold before each release mission, adapting to different satellite shell materials, temperature changes, and other environmental factors, thereby overcoming the shortcomings of each method. Furthermore, through a logical algorithm that integrates and judges data from both monitoring methods, four operating conditions can be clearly distinguished: normal release, limit switch 5 malfunction, impedance monitoring false alarm, and release failure. This provides irreplaceable first-hand data for on-orbit fault diagnosis and post-failure resetting, improving the safety and practicality of equipment operation.

[0056] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dual-redundant autonomous monitoring system for CubeSat release status, comprising a CubeSat release unit, a short message communication antenna, a short message communication module, an impedance monitoring unit, a limit switch, a signal acquisition and processing unit, and a data reporting unit, characterized in that: The cubestar release unit is provided with a cavity for accommodating the cubestar and an ejection mechanism for ejecting the cubestar out of the cavity. The short message communication antenna is mounted on the body of the CubeSat release unit, and the short message communication antenna is equipped with near-field radiation, and the near-field radiation area covers the cavity of the CubeSat release unit. The short message communication antenna is electrically connected to a short message communication module, which is used to interact with an external communication system. The short message communication antenna is electrically connected to an impedance monitoring unit, which is used to transmit a detection signal and measure the input impedance or reflection coefficient of the short message communication antenna. The cubesat release unit has at least two limit switches on the contact surface with the cubesat body; The signal acquisition and processing unit is electrically connected to the impedance monitoring unit and multiple limit switches, and each of the multiple limit switches and the signal acquisition and processing unit is an independent channel, used to acquire impedance monitoring data and limit switch status, and perform fusion judgment. The data reporting unit is electrically connected to the signal acquisition and processing unit and the short message communication module, respectively, and is used to send the fusion judgment result to the ground control center through the short message communication module.

2. The CubeSat Release Status Dual Redundancy Autonomous Monitoring System according to claim 1, characterized in that: The cavity structure and ejection mechanism of the CubeSat release unit are both existing standard CubeSat release device structures.

3. The CubeSat Release State Dual Redundancy Autonomous Monitoring System according to claim 1, characterized in that: The impedance monitoring unit includes a directional coupler and a power detector. The directional coupler is connected between the radio frequency output terminal of the short message communication module and the short message communication antenna. The power detector is used to measure the forward power and reflected power, and calculate the reflection coefficient or voltage standing wave ratio accordingly.

4. The CubeSat Release Status Dual Redundancy Autonomous Monitoring System according to claim 1, characterized in that: The signal acquisition and processing unit includes a microcontroller, which has a fusion judgment algorithm residing inside. The fusion judgment algorithm outputs a judgment result based on whether the impedance change output by the impedance monitoring unit exceeds a preset threshold and whether the state of the limit switch changes.

5. A dual-redundant autonomous monitoring method for CubeSat release status according to any one of claims 1 to 4, characterized in that: The specific steps are as follows: S1. Reference calibration: Before the CubeSat is loaded into the release mechanism cavity and the release command is executed, the first input impedance of the short message communication antenna is measured and stored by the impedance monitoring unit, and the first state of the limit switch is recorded at the same time. S2. Release command execution: The ejection mechanism receives the release command and executes the ejection action; S3. Real-time monitoring: Within a preset time window after the release command is executed, impedance monitoring and limit switch status monitoring are performed in parallel to obtain the second input impedance and the second status. S4. Fusion Judgment: Based on whether the difference between the first input impedance and the second input impedance exceeds a preset threshold, and whether the first state and the second state are the same, a fusion judgment is performed and the result is output. S5. Result Reporting: The fusion judgment result is sent to the ground control center via the short message communication module.

6. The dual-redundant autonomous monitoring method for CubeSat release state according to claim 5, characterized in that: The fusion judgment step specifically includes: When the difference between the second input impedance and the first input impedance exceeds a preset threshold and the second state is different from the first state, the output is "Release successful"; When the difference between the second input impedance and the first input impedance exceeds a preset threshold and the second state is the same as the first state, the output is "Release successful, limit switch fault". When the difference between the second input impedance and the first input impedance does not exceed the preset threshold and the second state is different from the first state, the output is "Limit switch mistriggered, release pending confirmation"; When the difference between the second input impedance and the first input impedance does not exceed a preset threshold and the second state is the same as the first state, the output is "Release failed".

7. The dual-redundant autonomous monitoring method for CubeSat release state according to claim 5, characterized in that: In the reference calibration step, the first input impedance is determined by taking the average value of multiple measurements, and this value is used as the reference value for subsequent judgments.

8. The dual-redundant autonomous monitoring method for CubeSat release state according to claim 5, characterized in that: In the impedance monitoring step, the power of the detection signal emitted by the impedance monitoring unit is lower than the normal communication transmission power of the short message communication module, so as to avoid electromagnetic interference to satellites and other equipment.

9. The dual-redundant autonomous monitoring method for CubeSat release state according to claim 5, characterized in that: In the real-time monitoring step, the impedance monitoring unit reuses the normal communication transmission signal of the short message communication module to perform impedance measurement, instead of transmitting a separate detection signal.

10. A cubesat release mechanism, characterized in that, The system includes the dual-redundant autonomous monitoring system for the release status of a CubeSat as described in any one of claims 1 to 4.

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