A Satellite General Mission Scheduling Method and System Based on a Process Engine

Abstract

The present invention provides a satellite general mission scheduling method and system based on a process engine. The system first defines all task sets and rollback policies during the execution of space missions by the satellite. Then, a task plan and corresponding rollback policy are created for each task; during the operation of the system, a task instance is created for the task plan that meets the current execution conditions. The task instance executes according to the planned task process. If a failure or interruption occurs during the execution, operations are performed according to the rollback policy. The present invention reduces the research and development and test cycles of satellite mission scheduling and improves the flexibility and scalability of satellite missions through unified planning and execution of complex space missions of the satellite.

Description

Technical Field

[0001] The present invention relates to the technical field of aerospace systems, and particularly to a satellite general mission scheduling method and system based on a process engine. Background Art

[0002] During the execution of space missions by satellites, a complete mission chain is jointly completed through the interaction of multiple subsystems of the satellite and the ground system. For example, the mission chain for a satellite to image the Earth includes the cooperation and coordination of multiple systems such as the imaging mission of the payload, the driving and pointing mission of the antenna, the signal transmission mission, and the ground system reception mission; the imaging mission can be broken down into a set of different instructions: power-on instruction, imaging instruction, power-off instruction, etc.; the antenna driving mission can be broken down into: X-axis driving to a certain position instruction, Y-axis driving to a certain position instruction; signal transmission can be broken down into: transmitter power-on instruction, power output instruction, transmitter power-off instruction; these subdivided instructions need to be executed in a specific order under specific conditions such as specific time, geographical location, and satellite status; the usual approach is to calculate in advance the execution order and timing of each step before each mission execution, form a job list, upload the job list to the satellite through the TT&C channel, and the satellite executes each task in sequence according to the job list;

[0003] Due to different satellite platforms, different payloads, and different working mechanisms, there is no general method and system for satellite mission scheduling during the satellite development process, resulting in continuous increases in the scale and cost of the hardware (various processors, actuators, etc.) and software (scheduling algorithms, human-computer interaction methods) of the satellite mission scheduling function; at the same time, due to the lack of standardization and generalization, the reliability and security of mission scheduling lack inheritance.

[0004] How to achieve complex and diverse execution scenarios of satellite missions through a standardized and generalized system and platform has become an urgent problem to be solved.

[0005] The invention patent with patent document CN102866709A discloses a method for realizing the on-orbit mobile imaging task of an agile satellite. The user transmits the command parameters required for mobile imaging to the satellite through the satellite-to-ground link. The satellite can autonomously generate a set of commands. The on-board computer uses a data structure with two-dimensional indexes of task number and time information to store the commands. At the same time, in conjunction with the program-controlled data blocks designed for agile mobile tasks injected by the ground, the operations of adding tasks, deleting tasks, running tasks, and terminating tasks can be realized according to the needs of ground users. In addition, the on-board computer can back up and store the task-related instructions through the internal emergency data recovery module, and can restore the instructions after the on-board computer is reset or cut off, so as to ensure that the entire satellite continues to perform the task according to the predetermined mode. Different from the above scheme, the present invention adopts a dynamic task planning method with branch node condition judgment, rather than a stacked task sequence queue, which can more flexibly and autonomously execute satellite tasks, and the task scope is not limited to mobile imaging tasks.

[0006] The invention patent with the patent document CN105955812A discloses a method and system for scheduling earth observation satellite tasks, wherein the earth observation satellite tasks include observation tasks and downlink tasks, and the method includes: inserting observation tasks and / or downlink tasks into the earth observation satellite tasks according to preset constraints to obtain an initial earth observation satellite task sequence; calculating the initial earth observation satellite task sequence by a preset first algorithm to obtain a scheduled earth observation satellite task sequence. Inserting observation tasks and / or downlink tasks into the earth observation satellite tasks according to preset constraints to obtain an initial earth observation satellite task sequence, and optimizing the initial earth observation satellite task sequence by a first algorithm to obtain a scheduled earth observation satellite task sequence. Different from the above scheme, the present invention does not need to preset a certain fixed algorithm, but allows the user to configure a dynamic algorithm according to actual conditions, and the task scope is not limited to observation tasks and downlink tasks.

[0007] The invention patent with the patent document number CN108960483A discloses a satellite scheduling method, a processing system, and a software program product. The satellite scheduling method includes: a) generating an initial scheduling plan based on input requests related to tasks to be executed by one or more remote sensing satellites within a given time period; b) applying a genetic algorithm-based process to the initial scheduling plan to generate a genetic algorithm-based scheduling plan, which is optimized for a given task objective and complies with given constraints related to satellite resources, tasks to be executed, and the given time period; and c) applying a simulated annealing-based process to the genetic algorithm-based scheduling plan to generate a simulated annealing-based scheduling plan, which is suitable for a specific task objective, complies with the given constraints, and schedules more tasks in the simulated annealing-based scheduling plan than in the genetic algorithm-based scheduling plan. Different from the above solution, the present invention does not solve specific satellite task problems, but provides open and dynamic task planning means to implement different task planning schemes. Summary of the Invention

[0008] Aiming at the defects in the prior art, the purpose of the present invention is to provide a satellite general task scheduling method and system based on a process engine.

[0009] A satellite general task scheduling method based on a process engine provided by the present invention includes the following steps:

[0010] Define task planning steps: Define task planning and store the planned tasks in the task planning queue.

[0011] Instance creation steps: Run task scheduling and create task instances for task plans that meet the conditions.

[0012] Execution steps: Execute task instances and call satellite resources.

[0013] Rollback strategy definition steps: Define rollback strategies and the task plans they monitor.

[0014] Task instance monitoring steps: Perform corresponding rollback operations on faulty task instances.

[0015] Task manual interface steps: Monitor task plans and task instances and provide an operation interface for manual intervention.

[0016] Preferably, the define task planning steps include:

[0017] Execution frequency definition steps: Define the execution frequency of task plans, which are divided into one-time tasks and periodic tasks. If it is a one-time task, define the task trigger time. If it is a periodic task, define the periodic frequency of the task.

[0018] Preferably, the task planning includes a task node sub-component. A task planning can set multiple task nodes, and a task node describes the operations to be performed when the task execution reaches this node.

[0019] Preferably, the task nodes are divided into timer nodes, instruction nodes, and data nodes, where:

[0020] The timer node sets the waiting time of the node. When the corresponding task instance of this task node is executed, it will wait for the set time and then execute the next task node;

[0021] The instruction node sets the instruction code of the satellite. When the corresponding task instance of this instruction node is executed, it will trigger the instruction module of the satellite, send out the corresponding instruction, and then execute the next task node;

[0022] The data node sets the calculation formula of the satellite parameters. When the corresponding task instance of this data node is executed, it will perform data calculation, save the data result to the parameters of the satellite, and then execute the next task node.

[0023] Preferably, the task planning includes a task path sub-component. The task path connects two task nodes and describes the relationship between the previous and the next task nodes.

[0024] Preferably, the task paths are divided into branch paths, exclusive paths, and direct paths, where:

[0025] One task node is connected to multiple task nodes at the same time. After the task instance of the previous task node is executed, all the subsequent task nodes connected are executed simultaneously, with the branch path as the task instance;

[0026] One task node is connected to multiple task nodes at the same time. After the task instance of the previous task node is executed, only one or some of the subsequent task nodes are executed, with the exclusive path as the task instance;

[0027] One task node is only connected to another task node. After the task instance of the previous task node is executed, the next task node is continued to be executed, with the direct path as the task instance.

[0028] Preferably, the instance creation steps include:

[0029] Creation step: The system periodically polls the task set, and creates corresponding task instances according to the current time of the system and the cycle frequency of the task planning;

[0030] Marking step: After a one-time task creates a task instance, mark this task as inactive and stop polling.

[0031] Preferably, the execution steps include:

[0032] Functions or calculation formulas included in the parsing task;

[0033] When the task instance node is a timer node, execute the set waiting time;

[0034] When the task instance node is an instruction node, send the instruction module according to the instruction code;

[0035] When the task instance node is a data node, calculate satellite parameters according to the calculation formula;

[0036] After all task instance nodes are executed, find the next task instance node according to the task path connected to this task node;

[0037] If there is no next task node for the current task instance node, the task instance is executed and completed.

[0038] Preferably, the task instance monitoring step includes:

[0039] Monitor the running status of the task instance. When the running status is incorrect, it is considered that the task instance has a failure;

[0040] Monitor the running time of the task instance. When the running time of the task instance exceeds the set task duration, it is considered that the task instance has a failure;

[0041] After monitoring that the task instance has a failure, terminate the running of this task and execute the rollback strategy.

[0042] A satellite general task scheduling system based on a process engine provided by the present invention includes the following modules:

[0043] Task planning module: used to describe and record satellite tasks in the form of task nodes and task branches;

[0044] Task execution module: According to the description of the task plan, combined with the current satellite operation status, a dynamically generated execution module will call various resources of the satellite to execute the planned task;

[0045] Task parsing module: Parse into an executable programming language according to the task plan description to which the running task instance belongs;

[0046] Task monitoring module: includes a task rollback strategy and task monitoring execution; the task rollback strategy defines the rollback operations required to execute steps in different task plans when a task failure, interruption, or exception occurs, and the task monitoring execution will monitor all task instances. When a failure, interruption, or exception occurs in this instance, execute the rollback according to the task rollback strategy to which this task instance belongs;

[0047] Task artificial interface: Provide task information acquisition and task intervention instructions based on the satellite TT&C link.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] 1. The present invention solves the problems of non-uniformity and non-generality in the prior art satellite task scheduling system, reduces the satellite development cycle and cost, and improves reliability and safety.

[0050] 2. The present invention reduces the R & D and test cycles of satellite task scheduling by uniformly planning and executing complex satellite space tasks, and improves the flexibility and scalability of satellite tasks.

[0051] 3. The present invention adopts a dynamic task planning method with branch node condition judgment, which can more flexibly execute satellite tasks autonomously. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] By reading the following detailed description of the non-limiting embodiments with reference to the accompanying drawings, other features, objects and advantages of the present invention will become more apparent:

[0053] Figure 1 It is a flowchart of a satellite general task scheduling method based on a process engine.

[0054] Figure 2 It is a schematic diagram of task nodes and task paths.

[0055] Figure 3 It is a flowchart of a rollback operation of a satellite general task scheduling method based on a process engine.

[0056] Figure 4 It is a visualization schematic diagram of task planning. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0057] The present invention will be described in detail below with reference to specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that those of ordinary skill in the art can make several changes and improvements without departing from the concept of the present invention. These all belong to the protection scope of the present invention.

[0058] Such as Figures 1 to 4As shown in the figure, a satellite general mission scheduling method and system based on a process engine according to the present invention includes a mission planning module, a mission execution module, a mission parsing module, a mission monitoring module, a mission manual interface, and a system operation processing device. The mission planning module includes mission information planning, mission node planning, mission branch planning, and a mission planning set; the mission planning is used to describe and record satellite missions in the form of mission nodes and mission branches. The mission execution module includes mission instances, a mission instance set, and mission instance status; the mission instance is an execution module dynamically generated according to the description of the mission planning and in combination with the current satellite operation status, and will call various resources of the satellite to execute the planned mission. The mission parsing module parses the description of the mission planning to which the running mission instance belongs into an executable programming language, especially the parsing of functions and algorithms. The mission monitoring module includes a mission rollback policy and mission monitoring execution; the mission rollback policy defines the rollback operations required to execute steps when mission failures, interruptions, or exceptions occur in different mission plans, and the mission monitoring execution will monitor all mission instances. When a failure, interruption, or exception occurs in an instance, the rollback will be executed according to the mission rollback policy to which the mission instance belongs. The mission manual interface provides mission information acquisition and mission intervention instructions based on the satellite TT&C link. The system operation processing device refers to the satellite on-board computer.

[0059] A satellite general mission scheduling method based on a process engine provided by the present invention includes the following steps:

[0060] S1. Define the mission plan and store the planned mission in the mission plan queue;

[0061] The specific content of step S1 is as follows:

[0062] S11. Define the execution frequency of the mission plan, which is divided into one-time missions and periodic missions. If it is a one-time mission, the mission trigger time needs to be defined. If it is a periodic mission, the mission cycle frequency needs to be defined.

[0063] S12. The mission plan includes mission node sub-components, and multiple mission nodes can be set in one mission plan. The mission node describes the operations to be performed when the mission execution reaches this node. The mission nodes are divided into timer nodes, instruction nodes, and data nodes.

[0064] The specific content of step S1 is as follows:

[0065] S121. The timer node can set the waiting time of the node. When the corresponding mission instance of this mission node is executed, it will wait for the set time and then execute the next mission node;

[0066] S122. The instruction node can set the instruction code of the satellite. When the task instance corresponding to this instruction node is executed, it will trigger the instruction module of the satellite, send out the corresponding instruction, and then execute the next task node;

[0067] S123. The data node can set the calculation formula of the satellite parameters. When the task instance corresponding to this data node is executed, it will perform data calculation, save the data result to the satellite parameters, and then execute the next task node;

[0068] S13. The task planning includes a task path sub-component. The task path is the route connecting two task nodes, describing the relationship between the previous and the next task nodes. The task path is divided into a branch path, an exclusive path, and a direct path;

[0069] The specific content of the belonging step S13 is as follows:

[0070] S131. The branch path means that when a task node is connected to multiple task nodes at the same time, after the task instance of the previous task node is executed, the task instances of all the connected subsequent task nodes will be executed simultaneously. The branch path can set execution conditions and only execute the subsequent tasks that meet the conditions;

[0071] S132. The exclusive path means that when a task node is connected to multiple task nodes at the same time, after the task instance of the previous task node is executed, only the task instance of one of the subsequent task nodes will be executed. The exclusive path can set execution conditions and only execute the first subsequent task that meets the conditions;

[0072] S133. The direct path means that when a task node is only connected to another task node, after the task instance of the previous task node is executed, the task instance of the next task node will continue to be executed. The direct path does not need to set execution conditions;

[0073] S2. Run the task scheduling to create task instances for the task planning that meets the conditions;

[0074] The specific content of the belonging step S2 is as follows:

[0075] S21. The system periodically polls the task set and creates corresponding task instances according to the current time of the system and the cycle frequency of the task planning;

[0076] After a one-time task creates a task instance, it marks the task as inactive and no longer polls.

[0077] S3. Execute the task instance and call the satellite resources;

[0078] Preferably, the belonging step S3 further includes:

[0079] S31. Analyze the functions or calculation formulas included in the task;

[0080] S32. When the task instance node is a timer node, execute the set waiting time;

[0081] S33. When the task instance node is an instruction node, send the instruction module according to the instruction code;

[0082] S34. When the task instance node is a data node, calculate the satellite parameters according to the calculation formula;

[0083] S35. After all task instance nodes are executed, find the next task instance node according to the task path connected to this task node;

[0084] S36. If there is no next task node for the current task instance node, this task instance is executed and completed;

[0085] S4. Define the rollback strategy and the task plan it monitors;

[0086] The specific content of S4 is as follows:

[0087] S41. The rollback strategy refers to a series of instructions to return the satellite to the initial or normal state and parameters. When a task instance fails to execute, the satellite's state and parameters can be returned to the initial normal state through the rollback strategy.

[0088] S42. Different rollback strategies can select the corresponding task plans to be monitored, so that different task instances can execute different rollback strategies according to the required situations after a failure;

[0089] S43. The rollback strategy can set the task duration. When a task instance fails to execute within the task duration, it is considered that the task instance has failed;

[0090] S5. Monitor the task instance and perform corresponding rollback operations on the failed task instance.

[0091] The specific content of S5 is as follows:

[0092] S51. Monitor the running state of the task instance. When the running state is incorrect, it is considered that the task instance has failed;

[0093] S52. Monitor the running time of the task instance. When the running time of the task instance exceeds the set task duration, it is considered that the task instance has failed;

[0094] S53. When it is monitored that the task instance has failed, terminate the running of this task and execute the rollback strategy.

[0095] S6. Monitor the task plan and task instance, and provide an operation interface for manual intervention

[0096] Through the satellite's TT&C channel, the status of the mission plan and mission instance is downlinked, satellite remote control commands are received, mission plans are added, modified, deleted, or mission instances are terminated, rolled back, or executed;

[0097] More specifically, an embodiment of the present invention provides a satellite general mission scheduling method and system based on a process engine, including the following steps:

[0098] S1. Define a mission plan and add it to the mission set; In this embodiment, it is assumed that an earth imaging mission needs to be executed, and the mission plan corresponding to this mission is set as follows:

[0099] Task Name Task Frequency Task Trigger Method Remarks Image the Earth Periodic Task "Sub-satellite Point" == "Daytime" Image the Earth when the sub-satellite point is daytime

[0100] The settings of this task node are as follows

[0101]

[0102] The settings of this task path are as follows

[0103] Branch Type Previous Node Next Node Branch Condition (Function) Direct Path Imager Power-on Imaging Start Direct Path Imaging Start Imaging Wait Direct Path Imaging Wait Imaging End Direct Path Imaging End Imager Power-off Direct Path Imager Power-off Transmission Preparation Direct Path Transmission Preparation Calculate Download Conditions Exclusive Path Calculate Download Conditions Transmission Preparation TRUE Exclusive Path Calculate Download Conditions Antenna Drive X-axis FALSE Direct Path Antenna Drive X-axis Antenna Drive Y-axis Direct Path Antenna Drive Y-axis Transmitter Power-on Direct Path Transmitter Power-on Transmitter Power Output Direct Path Transmitter Power Output Transmitter Power-off

[0104] So far, the settings of this mission plan are completed, and the visual schematic diagram of the mission plan is as shown in Figure 4 shown.

[0105] S2. Run mission scheduling to create mission instances for mission plans that meet the conditions;

[0106] When the sub-satellite point of the satellite is during the day, the execution conditions of this example mission are met, and a mission instance of this mission plan is created;

[0107] S3. Execute the mission instance and call satellite resources;

[0108] During the execution of the example mission, it is executed in sequence according to the mission sequence such as "imaging instrument power on", "imaging start", "imaging waiting", etc.; When executing to the "downlink condition calculation" node, it is judged whether the condition is met according to the current position of the satellite. Since the next two paths of this node are exclusive paths, only when the position judgment condition is met, it enters the "antenna drive X-axis" node, otherwise it enters the "transmission preparation" node and waits for the next calculation; Until the "launcher shutdown" node is executed, the execution of this mission instance ends;

[0109] S4. Define the rollback strategy and the mission plan it monitors;

[0110] The rollback strategy in this example is as follows

[0111]

[0112] The rollback operation is as follows

[0113] Operation Sequence Rollback Operation Operation Type 1 Imaging End Instruction 2 Imager Power-off Instruction 3 Storage Area Reset Instruction

[0114] S5. Monitor the task instances and perform corresponding rollback operations on the faulty task instances;

[0115] When a fault or timeout occurs during the execution of the "imaging the earth" task, such as a fault of the imager computer crashing, perform a rollback operation according to the rollback strategy, stop the subsequent tasks, and the satellite returns to the normal state.

[0116] S6. Monitor the task planning and task instances and provide an operation interface for manual intervention

[0117] In this example, the status information of the satellite task planning and task instances can be transmitted through the satellite telemetry and remote control channel, and an operation interface for manual intervention is also provided to add, modify, delete the task planning, or terminate, roll back, and execute the task instances.

[0118] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which does not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined with each other arbitrarily.

Claims

1. A satellite general mission scheduling method based on a process engine, characterized in that, It includes the following steps: Define the task planning step: Define the task planning and store the planned tasks in the task planning queue; Instance creation step: Run the task scheduling to create task instances for the task planning that meets the conditions; Execution step: Execute the task instance and call the satellite resources; Rollback strategy definition step: Define the rollback strategy and the task planning it monitors; Task instance monitoring step: Perform corresponding rollback operations on the faulty task instances; Task manual interface step: Monitor the task planning and task instances and provide an operation interface for manual intervention; The define task planning step includes: Execution frequency definition step: Define the execution frequency of the task planning, which is divided into one-time tasks and periodic tasks. If it is a one-time task, define the task trigger time. If it is a periodic task, define the periodic frequency of the task; The task planning contains task node sub-components. A task planning can set multiple task nodes, and the task node describes the operations that need to be performed when the task execution reaches this node; The task planning contains task path sub-components. The task path connects two task nodes and describes the relationship between the previous and the next task nodes; The task paths are divided into branch paths, exclusive paths, and direct paths, where: One task node is connected to multiple task nodes at the same time. After the task instance of the previous task node is executed, all the connected subsequent task nodes are executed simultaneously, and the branch path is used as the task instance; One task node is connected to multiple task nodes at the same time. After the task instance of the previous task node is executed, only one or some of the subsequent task nodes are executed, and the exclusive path is used as the task instance; One task node is only connected to another task node. After the task instance of the previous task node is executed, the next task node is continued to be executed, and the direct path is used as the task instance.

2. The satellite general mission scheduling method based on a process engine according to claim 1, wherein, The task nodes are divided into timer nodes, instruction nodes, and data nodes, where: The timer node sets the waiting time of the node. When the corresponding task instance of this task node is executed, it will wait for the set time and then execute the next task node; The instruction node sets the instruction code of the satellite. When the task instance corresponding to this instruction node is executed, it will trigger the instruction module of the satellite, send the corresponding instruction, and then execute the next task node; The data node sets the calculation formula of the satellite parameters. When the task instance corresponding to this data node is executed, it will perform data calculation, save the data result to the satellite parameters, and then execute the next task node.

3. The satellite general mission scheduling method based on a process engine according to claim 1, characterized in that The instance creation step includes: Creation step: The system periodically polls the task set and creates corresponding task instances according to the current time of the system and the periodic frequency of the task planning; Marking step: After a one-time task creates a task instance, mark the task as inactive and stop polling.

4. The satellite general mission scheduling method based on a process engine according to claim 2, wherein The execution step includes: Parse the functions or calculation formulas contained in the task; When the task instance node is a timer node, execute the set waiting time; When the task instance node is an instruction node, send the instruction module according to the instruction code; When the task instance node is a data node, calculate the satellite parameters according to the calculation formula; After all task instance nodes have been executed, the next task instance node is found according to the task path connected to the task node; If there is no next task node for the current task instance node, the task instance is executed and completed.

5. The satellite general mission scheduling method based on a process engine according to claim 1, characterized in that The task instance monitoring steps include: Monitoring the running status of the task instance. When the running status is an error, it is considered that the task instance has failed; Monitoring the running time of the task instance. When the running time of the task instance exceeds the set task duration, it is considered that the task instance has failed; After monitoring that the task instance has failed, terminate the running of the task and execute the rollback policy.

6. A satellite general mission scheduling system based on a process engine for implementing the method according to claim 1, characterized in that It includes the following modules: Task planning module: used to describe and record satellite tasks in the form of task nodes and task branches; Task execution module: a dynamically generated execution module according to the description of the task plan and combined with the current satellite operation status, which will call various resources of the satellite to execute the planned tasks; Task parsing module: parsed into an executable programming language according to the task plan description to which the running task instance belongs; Task monitoring module: includes task rollback policy and task monitoring execution; the task rollback policy defines the rollback operations to be executed for different task plans when task failures, interruptions or exceptions occur, and the task monitoring execution will monitor all task instances. When a failure, interruption or exception occurs to the instance, execute the rollback according to the task rollback policy to which the task instance belongs; Task manual interface: provides task information acquisition and task intervention instructions based on the satellite TT&C link.

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