Methods and computer program products for autonomous control of lunar far-side sampling mechanism avoidance.

Abstract

This application discloses a method and computer program product for autonomous control of lunar far-side sampling mechanism avoidance, relating to the technical field of space exploration. The method includes: analyzing the branch working state of the sampling mechanism before avoidance; determining multiple midpoints of the sampling mechanism's movement based on these branch working states; identifying the midpoint that would obstruct the ascent vehicle's takeoff from these midpoints; generating an avoidance trajectory for the sampling mechanism based on the determined midpoints; decomposing the sampling mechanism's actions into a series of execution steps based on the avoidance trajectory; adding monitoring telemetry to each execution step and determining its start time to form an autonomous control sequence; and verifying and checking the autonomous control sequence until it meets the requirements. This overcomes the ground control continuity problem that may arise from the dependence on relay communication arcs and quality during the avoidance process of existing lunar far-side sample return probes.

Description

Technical Field

[0001] This application belongs to the field of space exploration technology and relates to a method and computer program product for autonomous obstacle avoidance control of a sampling mechanism on the far side of the moon. Background Technology

[0002] Sampling and encapsulation are crucial components of unmanned lunar sample return missions. The sampling mechanisms will undergo multiple large-scale movements within the sampling area and encapsulation container. The encapsulation container, responsible for sealing the lunar surface, will perform a combination of rotation, descent, and actuation maneuvers. These complex lunar mechanism controls are typically achieved remotely via uplink command channels and downlink telemetry links between Earth and space. One of the core tasks of unmanned lunar sample return missions is to return lunar samples to Earth, and ensuring the sampling mechanism is properly positioned to avoid obstacles before the lunar probe's launch is a prerequisite. Therefore, research on obstacle avoidance by the sampling mechanism is an indispensable part of lunar sample return missions.

[0003] Among the lunar exploration missions conducted both domestically and internationally, the US Surveyor mission used a surface sampling mechanism to excavate and collect lunar regolith on the near side of the moon, transfer samples, and avoid obstacles. The Soviet Luna mission used a pendulum-type drilling and sampling mechanism to drill and core samples, transfer samples, and seal them. China's Chang'e 5 mission used a drilling and sampling device and a surface sampling robotic arm to collect, transfer, and initially seal lunar regolith samples from the near side of the moon, and used a sealing container to complete the lunar surface sealing. All these missions' probes were located on the near side of the moon, and all used ground-based remote control to complete the obstacle avoidance work. For lunar far-side exploration missions, relay satellites become an indispensable bridge for information exchange between the lunar probe and the ground. The arc constraint and communication quality of the relay satellite are factors that cannot be ignored in the obstacle avoidance design of the sampling mechanism. Improving the autonomous obstacle avoidance capability of the sampling mechanism is an important guarantee for enhancing the reliability and safety of the lunar far-side sampling and sealing process. Summary of the Invention

[0004] The technical problem solved by this application is to overcome the shortcomings of the prior art and provide an autonomous control implementation method for lunar far-side sampling mechanism avoidance, which overcomes the ground control continuity problem that may be caused by the dependence on relay communication arc and relay communication quality during the avoidance process of the sampling mechanism of the lunar far-side sampling return probe.

[0005] Based on my country's lunar far-side sampling and packaging development work, a common avoidance trajectory for the sampling mechanism in multiple positions and states was designed for the avoidance process. The modular working mode of the sampling mechanism was determined, and an autonomous control sequence combining state-driven and time-controlled mechanisms was proposed. An autonomous control triggering, implementation, and cancellation mechanism was formulated, thus forming the autonomous avoidance control capability of the sampling mechanism of the lunar far-side sampling return probe.

[0006] The technical solution provided in this application is as follows:

[0007] A method for autonomous control of lunar far-side sampling mechanism avoidance is disclosed for lunar surface sampling and packaging operations of a lunar probe. The lunar probe includes a lander and an ascender. The ascender is connected to the upper surface of the lander and can detach from the lander independently. A sampling mechanism is installed on the lander. A sealed packaging container is disposed on the surface of the ascender facing away from the lander. The sampling mechanism is used to collect samples and place them inside the sealed packaging container. The method includes:

[0008] S1: Analyze the branch working state of the sampling mechanism before avoidance, determine the midpoint of the movement of multiple sampling mechanisms based on the branch working state of the sampling mechanism, and determine the midpoint that hinders the take-off of the ascender among the midpoints of the movement of multiple sampling mechanisms.

[0009] S2: Generate the avoidance trajectory of the sampling mechanism based on the determined intermediate point; the initial point of the avoidance trajectory is a point on the entire set path of the sampling mechanism from the start of canister placement or direct sample placement to the end; the endpoint of the avoidance trajectory is below the top surface of the lander; the distance from the initial point to the endpoint includes three segments: the first segment is the movement from the initial point position along a direction perpendicular to the surface of the lander where the ascender is installed, moving away from the ascender, to the endpoint of the first segment; the second segment is the movement from the endpoint of the first segment along a direction parallel to the surface of the lander where the ascender is installed, until it is located next to the probe, reaching the endpoint of the second segment; the third segment is the straight line from the endpoint of the second segment to the endpoint of the avoidance trajectory.

[0010] S3: Based on the avoidance trajectory, the sampling mechanism's actions are decomposed into a series of execution steps. Monitoring telemetry is added to each execution step, and the start time is determined to form an autonomous control sequence. According to the autonomous control sequence, when the start time of a certain execution step is reached, the sampling mechanism executes according to the content of the execution step. After execution, the status of the sampling mechanism is judged by monitoring telemetry to determine whether the execution is in place. If the execution is in place, when the start time of the next execution step is reached, the sampling mechanism executes according to the next execution step. If the execution is not in place, it stops.

[0011] S4: Verify and validate the autonomous control sequence until it meets the requirements.

[0012] In S2, the distance between the avoidance trajectory and the nearest point of each intermediate point is no greater than the local fine-tuning range.

[0013] The second segment of the avoidance trajectory is a rotational motion at the same height, with the axis of rotation being the connection point between the oversampling mechanism and the lander and perpendicular to the upper surface of the lander.

[0014] In S3, when the autonomous control sequence is started, if the sealed container is in one of three states: open, closed but not sealed, or sealed, the process starts with the open lid and connects the lid rotation to close, the descent and sinking, and the sealing action into a combined process to form a continuous execution step.

[0015] In S3, when the autonomous control sequence is started, the execution time margin for each execution step is not less than 20%.

[0016] The start trigger time of the autonomous control sequence is T0 = T e -1.2×ΔT, where T e The latest time set for the separation of the ascender and lander; ΔT is the total execution time ΔT of the entire autonomous control sequence.

[0017] In step S4, the autonomous control sequence is checked and verified until it meets the requirements, including:

[0018] The autonomous control sequence, combined with the lunar probe's digital simulation model, simulates all possible entry states to conduct a digital simulation of the avoidance process, confirming the correctness of the process and the safety of the trajectory.

[0019] Generate instruction data from the autonomous control sequence;

[0020] The software and hardware of the verification software are used to perform dual verification of the instruction data with the target machine to confirm the correctness of the instruction format, data field parameters and execution time;

[0021] The command data, combined with the ground-based physical verification platform of the lunar probe, was used to simulate the avoidance process under different working conditions, confirming the compatibility of the physical verification autonomous control sequence, sampling mechanism, sealed packaging container and the physical verification platform of the lunar probe.

[0022] Before the sampling mechanism begins operation, the autonomous control sequence is uploaded to and stored on the lunar probe.

[0023] Before the lunar far side probe performs its avoidance operation, it unloads the autonomous control sequence command data back to the ground to confirm the consistency between the uplink injected data and the unloaded sequence data. After confirming that it is correct, it enables the autonomous avoidance control function and puts the autonomous control sequence command data into an active waiting state.

[0024] The lunar probe is equipped with a communication unit, an integrated management unit, a power supply unit, a sampling control unit, and a packaging control unit. Ground control sends control signals to the communication unit via relay satellite. The communication unit receives the control signals and sends them to the integrated management unit. The integrated management unit then sends sampling signals to the sampling control unit or packaging signals to the packaging control unit based on the control signals. The sampling control unit sends the sampling signals to the sampling mechanism, which performs sampling based on the signals. The packaging control unit sends packaging signals to the sealing packaging container, which then controls its lid to seal the opening of the sealing packaging container based on the packaging signals.

[0025] The integrated management unit stores the instruction data of the aforementioned autonomous control sequence. When the integrated management unit is executed by the processor, it implements the execution steps corresponding to the instruction data of the autonomous control sequence. If the avoidance process is successfully implemented with the support of the relay satellite, the ground sends an instruction to disable and delete the autonomous control sequence, canceling the execution opportunity of the subsequent autonomous control sequence. If the relay satellite disconnects from the lunar probe, causing the avoidance process to remain unexecuted until the time reaches the start trigger time T0 of the autonomous control sequence, and if the autonomous control sequence is still not canceled, the autonomous control sequence is executed.

[0026] A computer program product includes a computer program / instructions that, when executed by a processor, implement the steps of any of the methods described above.

[0027] Therefore, compared with the prior art, the control method of the present invention has the following beneficial effects:

[0028] 1) The relay dependency problem in the avoidance process of the lunar far-side sampling mechanism was solved. Through the coordination between the spacecraft and the ground and the formulation of autonomous control strategies on the spacecraft, an integrated method of supervised avoidance with relay support and autonomous avoidance without relay support was proposed.

[0029] 2) A method for determining the common avoidance trajectory of the sampling mechanism in multiple positions and states above the probe is proposed to ensure the safety and reliability of the sampling mechanism's avoidance before the probe takes off and ascends;

[0030] 3) An autonomous control sequence for sampling mechanism avoidance combining state-driven and time-controlled approaches was developed, enabling the implementation of avoidance operations for sampling mechanisms without relays on the far side of the moon.

[0031] 4) A complete working method for the ground simulation verification of the autonomous control sequence for sampling mechanism avoidance and the lunar surface use control was proposed, laying the foundation for efficient and safe autonomous control implementation. Attached Figure Description

[0032] Figure 1 This is a flowchart illustrating the implementation of autonomous control for obstacle avoidance in the sampling mechanism of this invention.

[0033] Figure 2 This is a schematic diagram of a typical state of the sampling mechanism before avoidance in this invention, where a is a state diagram of nominal tank placement, b is a state diagram of direct sampling, and c is a state diagram of the beginning of avoidance.

[0034] Figure 3 This is a schematic diagram of the sampling mechanism avoiding the common trajectory in this invention;

[0035] Figure 4 This is a schematic diagram of the autonomous control instruction generation and verification in this invention;

[0036] Figure 5 This is a schematic diagram of the information flow that the sampling mechanism avoids in this invention.

[0037] Explanation of reference numerals: 1. Lander; 2. Ascendant;

[0038] 11. Sampling mechanism; 111. Robotic arm; 112. Sampler; 113. Encapsulation container;

[0039] 21. Sealed and encapsulated container; 22. Cover. Detailed Implementation

[0040] To make the objectives, technical solutions, and advantages of the present invention clearer, the embodiments disclosed in the present invention will be described in further detail below with reference to the accompanying drawings.

[0041] This application discloses an autonomous control method for avoiding obstacles in a lunar far-side sampling mechanism, used for lunar surface sampling and packaging operations of a lunar probe. The lunar probe includes a lander 1 and an ascender 2. The ascender 2 is connected to the upper surface of the lander 1 and can take off independently and separate from the lander 1. A sampling mechanism 11 is installed on the lander 1. The sampling mechanism 11 includes a robotic arm 111 and a sampler 112. The robotic arm 111 is connected to the upper surface of the lander 1, and the sampler 112 is connected to the other end of the robotic arm 111. The sampler 112 can be selectively connected to a packaging container 113. The packaging container is used to hold the sample collected by the sampler and is placed inside the sealed packaging container. A sealed packaging container 21 is provided on the surface of the ascender 2 away from the lander 1. The sealed packaging container 21 is provided with a cover 22. The sealed packaging container 21 is used to hold the sample or store the packaging container. The cover 22 is used to seal the opening of the sealed packaging container 21 after the sample is placed inside. Since the sampling mechanism 11 is located on the side of the ascender 2 away from the lander 1 during the process of placing the can into the sealed packaging container 21 or directly releasing the sample, the movement of the sampling mechanism 11 will obstruct the takeoff of the ascender 2. Therefore, the sampling mechanism 11 needs to make way so that the ascender 2 can take off smoothly.

[0042] The lunar probe is equipped with a communication unit, an integrated management unit, a power supply unit, a sampling control unit, and a packaging control unit. Ground control sends control signals to the communication unit via relay satellite. The communication unit receives the control signals and sends them back to the integrated management unit. The integrated management unit sends sampling signals to the sampling control unit or packaging signals to the packaging control unit based on the control signals. The sampling control unit sends the sampling signals to the sampling mechanism 11, which performs sampling based on the signals. The packaging control unit sends packaging signals to the sealing packaging container 21. The sealing packaging container 21, based on the packaging signals, controls the cover to seal the opening of the sealing packaging container 21.

[0043] The autonomous control implementation method of this patent forms a computer program / instruction, which in turn forms a computer program product. An integrated management unit is used to run this computer program product. When the computer program / instruction is executed by the processor, it can control the sampling control unit and the packaging control unit to implement the steps of the autonomous control implementation method.

[0044] The autonomous control implementation method includes the following steps: Step 1, avoidance entry state analysis, combining the task process analysis with the branch working state of sampling mechanism 11 before avoidance, determining the midpoints of multiple sampling mechanism 11 movements based on the branch working states of sampling mechanism 11, and identifying midpoints that may hinder the detector's takeoff; Step 2, common avoidance trajectory determination, based on the determined midpoints, and considering the movement range and mode of sampling mechanism 11, detector surface layout, etc., generating a multi-pose, multi-state common avoidance trajectory; Step 3, autonomous control sequence formulation based on state-driven and time-controlled mechanisms, combined with mechanism movement... The process involves several steps: 1) Designing characteristics, telemetry parameters, and time protection control; 2) Sequencing and decomposing the avoidance trajectory to form a control sequence with autonomous triggering, execution, and interpretation capabilities; 3) Time control and state judgment; 4) Digital simulation confirmation of the autonomous control sequence: Using the lunar probe's digital simulation model, simulating all possible entry states to verify the correctness of the process and the safety of the trajectory; 5) Generating command data for the autonomous control sequence: Based on the data injection method of the sampling mechanism 11 and combined with time stamp control, generating all the command data required for the autonomous control sequence; 6) Verifying the command data of the autonomous control sequence: Using verification software and the target machine to perform dual software and hardware verification of the command data, ensuring the correctness of the command format, data domain parameters, and execution time; 7) Physical verification of the autonomous control sequence: Using the sampling and packaging physical verification platform, performing physical verification of the avoidance process under different working conditions, verifying the compatibility of the autonomous control sequence with the product and probe; 8) Advance uploading of the autonomous control sequence: Based on the probe's operational progress, injecting the autonomous control sequence data blocks into the probe's integrated management unit via ground uplink for storage; 9) Autonomous control... Step 10: Autonomous control sequence unloading verification. Ground commands are sent to unload the autonomous control sequence data blocks from the corresponding sectors of the detector's integrated management unit, confirming the consistency of the data between the detector and the ground. Step 11: Autonomous control sequence early cancellation. If the avoidance process is successfully implemented with the support of relay satellites, ground commands are sent to disable and delete the autonomous control sequence, canceling the execution opportunity of subsequent autonomous control sequences. Step 12: Autonomous control sequence fully autonomous execution. According to the time control mechanism, if the autonomous control sequence has not been cancelled by the time point of autonomous execution, the detector's integrated management unit organizes all equipment on the detector to autonomously implement the avoidance process.

[0045] In this invention, considering that the sampling mechanism 11 itself is in a fault-free state, and that each step of the execution after receiving the instruction can be performed correctly, the autonomous avoidance process of the sampling mechanism 11 is controlled mainly from the aspects of analysis and design, simulation and verification, input and verification, execution or cancellation. The correctness of the design of the autonomous control function is ensured through the analysis, design, simulation and verification links, and the on-orbit maintainability of the autonomous control function is ensured through the input, verification, execution and cancellation links.

[0046] Specifically, in step one, the following steps are performed: First, the state of the sampling mechanism before avoidance is analyzed and summarized, mainly including: analyzing which aspects might hinder the probe's takeoff for the two possible modes of nominal and direct sampling that the lunar far-side sampling mechanism may adopt; summarizing the midpoints of movement above the probe and the possible attitudes of the sampler in both modes; and analyzing the differences in the sampler's state before and after direct sampling, and the differences in the sampler's state before and after releasing the container. Then, all possible entry conditions for the autonomous control process are determined, establishing the correct boundaries for the design of the autonomous control sequence.

[0047] In step two, the following steps are performed: Based on the Cartesian motion mode and joint space motion mode of the sampling mechanism, and combined with the layout of the detector surface products, a common safety avoidance trajectory is determined, which has a safety distance that meets the requirements.

[0048] The initial point of the safety avoidance trajectory is one of the intermediate points. Intermediate points are derived from: 1. During the nominal placement process, the sampling mechanism initially moves the sample to the container status observation point, and then places the sample in the sealed container 21 from the container status observation point until release, along the entire set path; 2. During the direct placement process, the sampling mechanism initially moves the sample to the direct placement fine-tuning starting point, and the sampling mechanism releases the sample at the direct placement point, along the entire set path from the direct placement fine-tuning starting point to the direct placement point; 3. The avoidance starting point is the position after the sample is released during the nominal placement or direct placement process.

[0049] In step three, the following steps are performed: Based on the determined common avoidance trajectory, the mode control, speed control, acceleration control, and state interpretation telemetry decomposition design for each segment of the trajectory are carried out; the motion time of each segment of the sampling mechanism is estimated, and a reasonable mechanism motion protection time is determined; combined with work events such as lunar surface sampling and packaging, scientific exploration, and takeoff and ascent preparation, the starting point for triggering autonomous avoidance control is determined; and an autonomous avoidance control sequence combining time control and state drive is formed.

[0050] In step four, the following steps are performed: using the lunar probe to sample and encapsulate digital simulation, the autonomous control sequence generated in step three is introduced into the system model, and the various entry conditions determined in step one are used as the starting states. The system verifies whether the collaborative workflow of the relevant equipment is correct and confirms whether the mechanism's motion trajectory has an appropriate safe distance from other surface equipment.

[0051] In step five, the following steps are performed: Based on the data injection and usage guidelines of the sampling mechanism, a single instruction is generated in conjunction with the autonomous control sequence, and a time code is added to the single instruction according to the instruction format of the time control, forming a usable sequence instruction.

[0052] In step six, the following steps are performed: Using instruction verification software, the instruction format and data field content of all instruction data are reverse-engineered and compared. All instructions on the target machine are checked for passability, and the correctness of all instruction data is confirmed through double verification.

[0053] Step seven involves: using the ground-based physical verification platform of the lunar probe, simulating all possible entry states under different operating conditions, and using products in the same state to physically verify the avoidance process, further confirming the correctness of the procedure, the safety of the trajectory, the completeness of the interpretation, and the compliance of the time control. The ground-based physical verification platform for the lunar probe is the same as the lunar probe itself.

[0054] In step eight: Before the lunar far-side probe sampling mechanism starts working, ground operators will upload the autonomous control sequence data block to the probe's integrated management unit for storage.

[0055] In step nine: Before the lunar far-side probe avoids the terrain, ground operators unload the autonomous control sequence command data stored in the probe's integrated management unit back to the ground. Ground operators confirm the consistency between the uplink injected data and the unloaded sequence data through manual inspection and tool comparison. After confirming that it is correct, the autonomous control function for avoidance is enabled and put into an active waiting state.

[0056] In step ten: According to the strategy for using the autonomous control sequence for lunar far-side avoidance, the avoidance process of lunar far-side sampling and encapsulation preferentially adopts a supervised implementation method with relay support. During the stable operation of relay communication support, the autonomous control sequence is first in an active waiting state. After the avoidance process is completed with relay support, the ground sends a command to disable and delete the autonomous control sequence, and cancels the subsequent execution opportunity.

[0057] In step eleven: According to the strategy of autonomous control sequence for avoiding the far side of the moon, if the relay communication is interrupted during the operation of the sampling mechanism and has not been restored before the lunar surface takeoff preparation, according to the time control of each instruction data in the autonomous control sequence, when the autonomous control sequence is still enabled at the autonomous execution time, each device on the detector integrated management unit organizes the autonomous avoidance process.

[0058] Example 1

[0059] This invention provides an autonomous obstacle avoidance control method for a lunar far-side sampling mechanism, used in the obstacle avoidance process of the lunar far-side sampling mechanism towards the probe. The method mainly includes four aspects: analysis and design, simulation and verification, data upload and calibration, and execution or cancellation. A typical autonomous obstacle avoidance control implementation process for a sampling mechanism is as follows: Figure 1 As shown, the autonomous control implementation method of the present invention is specifically as follows:

[0060] The lunar far-side sampling mechanism typically operates in two modes: nominal sampling and direct sampling. In nominal sampling mode, the sampling mechanism moves above the detector to perform tasks such as transferring and aligning the primary packaging container. Sealing is then performed after the container is released and withdrawn. During this process, the sampler is vertical; before release, it holds the primary packaging container to form a combined unit; after release, it closes and remains in its original envelope state. The sampling mechanism's movement above the detector passes through several intermediate points, including: the container transfer midpoint, the release fine-tuning starting point, the release point, the container status observation point, and the avoidance starting point. In direct sampling mode, the sampling mechanism moves above the detector to directly transfer the collected sample to the sealed container. Sealing is performed after multiple direct sampling operations are completed and withdrawn. During this process, the sampler is tilted and closes in its original envelope state. The sampling mechanism's movement above the detector passes through several intermediate points, including: the direct sampling fine-tuning starting point, the direct sampling point, the container status observation point, and the avoidance starting point. A typical entry state during the avoidance process is as follows: Figure 2 As shown.

[0061] For the sampling mechanism's obstacle avoidance, considering three states—before container release, after container release, and direct sample release—the common obstacle avoidance trajectory involves raising the sampler to a sufficiently high position within the reachable space. This eliminates the differences in the height of the primary packaging container and the differences in the tilt and vertical height of the sampler in these three states. The first step of the obstacle avoidance trajectory is determined to be an incremental vertical lifting motion. This step moves from the initial position along a direction perpendicular to the surface of the lander's ascender, away from the ascender, to the first segment's endpoint. Considering that the sampling mechanism and terminal sampler located above the probe would obstruct takeoff, moving from above the probe to the side while maintaining a certain height can quickly eliminate takeoff channel interference. The second step of the obstacle avoidance trajectory is determined to be a rotational motion at the same height. This motion moves from the first segment's endpoint to the second segment's endpoint, which is the obstacle avoidance midpoint. When the sampling mechanism and sampler (including the container if the primary encapsulation container has not yet been released) are positioned beside the probe, to ensure that there are no obstacles within a safe distance during takeoff and ascent at a small angle, the sampling mechanism and sampler move as a whole from beside the probe to beside the lander 1. This ensures that the probe takeoff is completely unobstructed. The third step of determining the avoidance trajectory is a diagonal descent. This step moves from the end of the second segment to the end of the avoidance trajectory, with the end point being the avoidance point. During this period, the sealed encapsulation container 21 may be in three states: open, closed but not sealed, and sealed. Starting from the open state, the process can be combined by rotating and closing the lid, descending and sinking, and actuating the seal. The avoidance trajectory of the sampling mechanism is as follows: Figure 3As shown. Considering the randomness of the timing of relay communication disconnection, the starting point of the sampling mechanism's avoidance may be any one of the seven intermediate points: container transfer intermediate point, release fine-tuning starting point, release point, direct placement fine-tuning starting point, direct placement point, container status observation point, and avoidance starting point. The designed common avoidance trajectory must ensure that the distance to the nearest point among these seven intermediate points is no greater than the local fine-tuning range (the radius of the sphere space can be considered to be no greater than 2cm). Through autonomous state detection by the on-board control program, if the preceding steps have been completed, the mechanism can be in a holding state. When it is necessary to execute the unfinished steps, the mechanism can continue to move.

[0062] The autonomous control of the sampling mechanism's obstacle avoidance process requires the onboard product to have single-step automatic execution capabilities, such as the ability to perform Cartesian linear planning, joint space planning, and incremental motion planning based on a given target point; the sealed packaging container should be able to correctly execute steps such as rotating and closing the lid and descending and sinking according to instructions. The design of the autonomous control sequence is transformed into decomposing the realization of the sampling mechanism's common obstacle avoidance trajectory into a series of execution steps. Autonomous control is free from ground personnel supervision, and onboard monitoring and telemetry are added to each execution step, with time design. The sampling mechanism's movement should be considered as an acceleration, constant speed, and deceleration process, with a time margin of no less than 20% for each execution step. The failure to meet the lunar far-side relay conditions is a prerequisite for the implementation of obstacle avoidance autonomous control, and a constraint time T before takeoff and ascent is required. e This is the rear line after the avoidance is completed. After completing the decomposition and step-by-step timing design of each step, the total execution time ΔT of the entire autonomous control sequence should be calculated, and the starting trigger time T0 = T of the autonomous control sequence should be determined. e -1.2×ΔT, as shown in Table 1, take 0:00:00 on XX / XX / XXXX as T0, and then generate the trigger time of each step in the sequence according to the time requirements of each step.

[0063] Table 1. Examples of sampling mechanism avoidance autonomous control sequence content.

[0064] Serial Number Triggering time Execution steps Onboard monitoring and telemetry 1. XXXX-XX-XX T00:00:00 Cartesian mode settings Sampling mechanism working mode 2. XXXX-XX-XX T00:00:05 Avoidance starting point setting Target location of sampling mechanism 3. XXXX-XX-XX T00:00:10 Desired linear velocity setting Sampling mechanism linear velocity setting 4. XXXX-XX-XX T00:00:15 End-point desired linear acceleration setting Sampling mechanism acceleration settings 5. XXXX-XX-XX T00:00:30 Sampling mechanism starts movement Sampling mechanism working status 6. XXXX-XX-XX T00:10:00 Cartesian mode settings Sampling mechanism working mode 7. XXXX-XX-XX T00:10:05 Vertical Incremental Motion Settings Sampling agency target increment 8. XXXX-XX-XX T00:10:10 Desired linear velocity setting Sampling mechanism linear velocity setting 9. XXXX-XX-XX T00:10:15 Desired linear acceleration settings Sampling mechanism acceleration settings 10. XXXX-XX-XX T00:48:40 Sampling mechanism starts movement Sampling mechanism working status 11. XXXX-XX-XX T00:14:00 Sealed control unit open Sealed voltage state 12. XXXX-XX-XX T00:14:30 Hermetically pre-programmed packaging work Sealed working condition 13. XXXX-XX-XX T00:22:30 Explosives busbar return pyrotechnic switch status 14. XXXX-XX-XX T00:23:30 Cover sealing action Initiation current 15. XXXX-XX-XX T00:24:00 Sealed control unit off Sealed voltage state 16. XXXX-XX-XX T00:25:00 Fireworks busbar return line breakage pyrotechnic switch status 17. XXXX-XX-XX T00:25:30 Joint Space Planning Mode Settings Sampling mechanism working mode 18. XXXX-XX-XX T00:26:00 Movement to avoidance midpoint setting Target location of sampling mechanism 19. XXXX-XX-XX T00:26:05 Desired angular velocity setting Sampling mechanism angular velocity setting 20. XXXX-XX-XX T00:26:00 Desired angular acceleration settings Sampling mechanism angular acceleration setting 21. XXXX-XX-XX T00:26:30 Sampling mechanism starts movement Sampling mechanism working status 22. XXXX-XX-XX T00:33:30 Joint Space Planning Mode Settings Sampling mechanism working mode 23. XXXX-XX-XX T00:34:00 Move to the avoidance point Target location of sampling mechanism 24. XXXX-XX-XX T00:34:05 Desired angular velocity setting Sampling mechanism angular velocity setting 25. XXXX-XX-XX T00:34:10 Desired angular acceleration settings Sampling mechanism angular acceleration setting 26. XXXX-XX-XX T00:34:30 Sampling mechanism starts movement Sampling mechanism working status 27. XXXX-XX-XX T00:39:30 Sampling mechanism power failure sequence settings Sampling agency serial number 28. XXXX-XX-XX T00:40:00 Sequence execution begins Sampling mechanism sequence execution status 29. XXXX-XX-XX T00:42:30 Sampling mechanism control unit power failure Sampling mechanism voltage state

[0065] After the autonomous control sequence for the sampling mechanism to avoid obstacles is generated, it is converted into a descriptive language that can be recognized by the digital simulation system. The control parameters such as working mode, target position, linear velocity, linear acceleration, angular velocity, and angular acceleration are set according to the step requirements. It is confirmed that the avoidance trajectory can complete all tasks under various possible entry states, that the minimum safe distance of the mechanism throughout the entire movement process meets the requirements, that the simulation time of each step conforms to the step-by-step time of the design, and that the coordination between the sampling mechanism and the sealed packaging container is confirmed.

[0066] Each step of the sampling mechanism's autonomous control sequence must be converted into instruction data before it can be executed. The instruction data includes information such as the trigger time, execution device, and instruction content, and generates frame headers, packet headers, and checksums according to the prescribed instruction format, forming a valid data block. The correctness and compatibility of the instructions are confirmed through manual review, software checks, hardware checks, and physical verification. Figure 4 As shown. During the physical verification process, the verification platform is used in conjunction with the sampler status of the sampling mechanism, the status of the sealed packaging container, and the simulated entry state of the sampling mechanism at 7 intermediate points. Using the determined autonomous control sequence and instruction data, combined with the actual sampling mechanism and sealed packaging container, the physical verification work is completed. The physical objects are used to further confirm that the control process is correct, the step-by-step time is reasonable, and the equipment spacing is safe.

[0067] Before the probe lands on the far side of the moon and begins its lunar surface work, the autonomous avoidance control sequence is injected into a predetermined sector of the probe's integrated management unit via a relay link from the ground. The data stored in this sector is then transferred to the ground via the relay link through an uplink command. Ground personnel compare the injected and transferred data manually or using tools to confirm their correctness. Once confirmed, the autonomous avoidance function is enabled. (If the relay link no longer supports uplinking at this time, since the sampling mechanism has not yet started working, there is no need to consider issues such as obstructing the probe's takeoff, and therefore no need to send an uplink autonomous control sequence.)

[0068] Under normal circumstances, the relay link between the ground control center, relay satellite, and lunar probe works stably. During sample collection, placement, primary packaging, and container grasping, the autonomous control sequence is in an active waiting state because the working time is still earlier than the triggering time. If the relay link is functioning normally, the sampling mechanism's avoidance and encapsulation will be completed with relay support (in the workflow, this time is still earlier than the trigger time). Ground personnel can monitor this process using telemetry, images, and other information. After the avoidance process is completed, the uploaded autonomous control sequence will be disabled via ground uplink, and the sequence command data stored in the detector's integrated management unit will be deleted. The autonomous control function will be revoked and will not be implemented again. If the relay link is disconnected during this period, the autonomous control sequence will remain in a waiting state at the originally planned avoidance time with relay support. If the relay link is restored before the autonomous control sequence trigger time, the avoidance work with relay support will be implemented as described above. If the relay link is not restored by the trigger time, the detector's integrated management unit will send corresponding commands to the control unit according to the time control requirements, driving the sampling mechanism to autonomously complete the avoidance process according to the designed trajectory. Figure 5 As shown, this allows for takeoff avoidance of the probe.

[0069] This embodiment also discloses a computer program product, including a computer program / instructions that, when executed by a processor, implement the steps of any of the methods described above.

[0070] The improvements in this patent are as follows:

[0071] An integrated method for relay-free autonomous control and relay-monitored control in the obstacle avoidance process of a lunar probe's sampling mechanism;

[0072] A design method for a shared avoidance trajectory for a lunar probe's sampling mechanism across multiple locations and states;

[0073] A state-driven and time-controlled autonomous control sequence design method for the avoidance process of a lunar probe's sampling mechanism;

[0074] Ground simulation verification of the autonomous control sequence for lunar probe sampling mechanism avoidance, and the full-process implementation method of lunar surface use control.

[0075] The contents not described in detail in this application specification are common knowledge to those skilled in the art.

[0076] The present application has been described in detail above with reference to specific embodiments and exemplary examples; however, these descriptions should not be construed as limiting the present application. Those skilled in the art will understand that various equivalent substitutions, modifications, or improvements can be made to the technical solutions and implementation methods of the present application without departing from the spirit and scope of the present application, and all such modifications and improvements fall within the scope of the present application. The scope of protection of the present application is determined by the appended claims.

Claims

1. A method for autonomous control of lunar far-side sampling mechanism, used for lunar surface sampling and packaging work of a lunar probe, the lunar probe including a lander (1) and an ascender (2), the ascender (2) being connected to the upper surface of the lander (1), and the ascender (2) being able to fly off independently and separate from the lander (1), a sampling mechanism (11) being installed on the lander (1), a sealed packaging container (21) being provided on the surface of the ascender (2) away from the lander (1), the sealed packaging container (21) being provided with a cover (22), the sampling mechanism (11) being used to collect samples and place the samples inside the sealed packaging container (21); characterized in that, include: S1: Analyze the branch working state of the sampling mechanism (11) before it avoids, determine the midpoint of the movement of multiple sampling mechanisms (11) based on the branch working state of the sampling mechanism (11), and determine the midpoint that hinders the take-off of the ascender (2) among the midpoints of the movement of multiple sampling mechanisms (11). S2: Generate the avoidance trajectory of the sampling mechanism (11) based on the determined intermediate point; the initial point of the avoidance trajectory is a point on the entire set path of the sampling mechanism (11) from the start of can placement or direct sampling to the end, and the end point of the avoidance trajectory is below the top surface of the lander (1). The distance from the initial point to the end point includes three segments. The first segment is to move from the initial point position along the direction perpendicular to the surface of the lander (1) where the ascender (2) is installed, and move away from the ascender (2) to the end point of the first segment. The second segment moves from the end of the first segment along the surface parallel to the ascender (2) installed on the lander (1) until it is located next to the probe and reaches the end of the second segment. The third segment moves in a straight line from the end of the second segment to the end of the avoidance trajectory. S3: Based on the avoidance trajectory, the execution action of the sampling mechanism (11) is decomposed into a series of execution steps. Monitoring telemetry is added to each execution step and the start time is determined to form an autonomous control sequence. According to the autonomous control sequence, when the start time of a certain execution step is reached, the sampling mechanism (11) executes according to the content of the execution step. After execution, the status of the sampling mechanism (11) is judged by monitoring telemetry to determine whether the execution is in place. If the execution is in place, when the start time of the next execution step is reached, the sampling mechanism (11) executes according to the next execution step. If the execution is not in place, it stops. S4: Verify and validate the autonomous control sequence until it meets the requirements; In step S4, the autonomous control sequence is checked and verified until it meets the requirements, including: The autonomous control sequence, combined with the lunar probe's digital simulation model, simulates all possible entry states to conduct a digital simulation of the avoidance process, confirming the correctness of the process and the safety of the trajectory. Generate instruction data from the autonomous control sequence; The software and hardware of the verification software are used to perform dual verification of the instruction data with the target machine to confirm the correctness of the instruction format, data field parameters and execution time; The command data, combined with the ground-based physical verification platform of the lunar probe, was used to simulate the avoidance process under different working conditions, confirming the compatibility of the physical verification autonomous control sequence, sampling mechanism, sealed packaging container and the physical verification platform of the lunar probe. Before the sampling mechanism begins operation, the autonomous control sequence is uploaded to and stored on the lunar probe. Before the lunar far side probe performs its avoidance operation, it unloads the autonomous control sequence command data back to the ground to confirm the consistency between the uplink injected data and the unloaded sequence data. After confirming that it is correct, it enables the autonomous avoidance control function and puts the autonomous control sequence command data into an active waiting state.

2. The autonomous control implementation method for lunar far-side sampling mechanism avoidance according to claim 1, characterized in that: In S2, the distance between the avoidance trajectory and the nearest point of each intermediate point is no greater than the local fine-tuning range.

3. The autonomous control implementation method for lunar far-side sampling mechanism avoidance according to claim 1, characterized in that: The second segment of the avoidance trajectory is a rotational motion at the same height, with the axis of rotation being the connection point between the oversampling mechanism and the lander and perpendicular to the upper surface of the lander.

4. The autonomous control implementation method for lunar far-side sampling mechanism according to claim 1, characterized in that, In S3, when the autonomous control sequence is started, if the sealed container is in one of three states: open, closed but not sealed, or sealed, the process starts with the open lid and connects the lid rotation to close, the descent and sinking, and the sealing action into a combined process to form a continuous execution step.

5. The autonomous control implementation method for lunar far-side sampling mechanism according to claim 1, characterized in that: In S3, when the autonomous control sequence is started, the execution time margin for each execution step is not less than 20%.

6. The autonomous control method for avoiding obstacles in a lunar far-side sampling mechanism according to claim 5, characterized in that: The start trigger time of the autonomous control sequence is T0=T e -1.2×ΔT, where T e The latest time set for the separation of the ascender (2) and the lander (1); ΔT is the total execution time ΔT of the entire autonomous control sequence.

7. The autonomous control implementation method for lunar far-side sampling mechanism according to claim 1, characterized in that: The lunar probe is equipped with a communication unit, an integrated management unit, a power supply unit, a sampling control unit, and a packaging control unit. Ground control sends control signals to the communication unit via relay satellite. The communication unit receives the control signals and sends them to the integrated management unit. The integrated management unit sends sampling signals to the sampling control unit or packaging signals to the packaging control unit based on the control signals. The sampling control unit sends the sampling signals to the sampling mechanism, which performs sampling based on the sampling signals. The packaging control unit sends packaging signals to the sealing packaging container, which controls the cover to seal the opening of the sealing packaging container based on the packaging signals.

8. The autonomous control implementation method for lunar far-side sampling mechanism according to claim 7, characterized in that: The integrated management unit stores the instruction data of the aforementioned autonomous control sequence. When the integrated management unit is executed by the processor, it can implement the execution steps corresponding to the instruction data of the autonomous control sequence. If the avoidance process is successfully carried out with the support of relay satellites, the ground will send a command to disable and delete the autonomous control sequence, and cancel the execution of subsequent autonomous control sequences. If the relay satellite loses communication with the lunar probe and the avoidance process is not executed until the start trigger time T0 of the autonomous control sequence is reached, and if the autonomous control sequence is still not canceled, the autonomous control sequence will be executed.

9. A computer program product comprising a computer program / instructions, characterized in that, When the computer program / instructions are executed by the processor, they implement the steps of the method described in any one of claims 1-6.

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