A control system and method for a spacecraft solar array swing mechanism

Abstract

The application relates to a control system and method for a spacecraft solar cell array swing mechanism, which comprises a drive backup switching module and two groups of circuits, the circuits comprising a CPU control module, a motor drive module, a feedback signal processing module and an A / B winding backup switching module; the CPU control module is connected with an upper computer of a spacecraft, and the motor drive module generates a drive signal to a stepping motor based on a control instruction of the CPU control module; the feedback signal processing module sends a preprocessed feedback signal to the CPU control module; the A / B winding backup switching module controls the switching of A / B windings of the stepping motor based on an instruction of the CPU control module; and the drive backup switching module controls the switching of A / B windings of the stepping motor of the +Y wing based on a control instruction of the upper computer of the spacecraft. Compared with the prior art, the application can accurately and reliably control the swing mechanism, monitors and eliminates the occurrence of faults within a certain limit, protects relevant equipment and ensures the swing angle precision.

Description

Technical Field

[0001] This invention relates to the field of space structures and mechanisms, and in particular to a control system and method for a spacecraft solar array oscillation mechanism. Background Technology

[0002] For many spacecraft, the electricity generated by solar arrays is the power source for their operation. A characteristic of low Earth orbit spacecraft orbits is that the angle between sunlight and the spacecraft's orbital plane changes significantly throughout its lifespan. To improve battery energy conversion efficiency, it is sometimes necessary to adjust the solar array's orientation to the sun to increase the effective usable area. Currently, existing spacecraft solar array drive methods are mainly divided into two categories: single-degree-of-freedom drive and two-degree-of-freedom drive.

[0003] A single-degree-of-freedom (DOF) drive device contains a one-dimensional drive mechanism. Driven by a drive motor, the connected solar array can rotate around an axis, thereby adjusting and expanding the solar array's illuminated area. However, a single-DOF drive device can only rotate a solar array on one axis at most. When applied to spacecraft, this means the solar array can only be oriented towards the sun in one direction. In the horizontal direction, the angle of the solar array must be adjusted by the spacecraft's own attitude control.

[0004] The dual-degree-of-freedom (DFD) drive system comprises a one-dimensional drive mechanism and a oscillating mechanism, which are connected but have different rotation axes. Compared to single-degree-of-freedom (DFD) drive systems, the DFD allows for omnidirectional adjustment of the solar array in space without requiring spacecraft attitude or position adjustments, achieving real-time solar array orientation and high adjustment efficiency. However, the DFD requires more sophisticated control technology and is more complex to operate. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art by providing a control system and method for the swing mechanism of a spacecraft solar cell array, which can accurately and reliably control the swing mechanism, monitor and eliminate faults within a certain limit, protect related equipment, and ensure the accuracy of the swing angle.

[0006] The objective of this invention can be achieved through the following technical solutions:

[0007] A control system for a spacecraft solar array swing mechanism, wherein there are two swing mechanisms, which are used to drive the ±Y-wing solar arrays on the spacecraft respectively. The power source of the swing mechanism is a stepper motor, and the stepper motor has two sets of windings, A and B, which are backups of each other. An offset detection sensor is installed on the solar array.

[0008] The control system includes a drive backup switching module and two sets of circuits. The circuits include a CPU control module, a motor drive module, a feedback signal processing module, and an A / B winding backup switching module.

[0009] The CPU control module is connected to the spacecraft's host computer.

[0010] The motor drive module is connected to the CPU control module and generates drive signals to the stepper motor based on the control instructions of the CPU control module.

[0011] The feedback signal processing module is connected to the CPU control module. After preprocessing the feedback signal, it is sent to the CPU control module. The feedback signal includes at least the stepper motor speed, operating current, and the bias position signal of the solar cell array.

[0012] The A / B winding backup switching module is connected to the CPU control module and controls the switching of the stepper motor A / B windings based on the instructions of the CPU control module.

[0013] The drive backup switching module is connected to the A / B winding backup switching module of two sets of lines, and controls the switching of the A / B windings of the stepper motor of the ±Y wing based on the control commands of the spacecraft host computer.

[0014] Furthermore, the circuit also includes a secondary power supply module, which converts the power supply on the spacecraft into the operating voltage required by the components in the control system.

[0015] Furthermore, the spacecraft is powered by a 28V power supply.

[0016] Furthermore, the CPU control module is connected to the spacecraft's host computer via a serial communication port.

[0017] Furthermore, the control system also includes a telemetry circuit module, which is used to enable communication between the spacecraft's host computer and the ground telemetry center.

[0018] Furthermore, the step angle of the stepper motor is 1.8°.

[0019] Furthermore, the control system is a modular single-unit structure, comprising multiple box-type structures. Each box-type structure includes a shell, reinforcing crossbars, printed circuit boards, fasteners, and electronic components. All the box-type structures are connected together and then installed on the spacecraft.

[0020] Furthermore, all the box-shaped structures are connected together with bolts, and the entire modular unit is fixed to the spacecraft with bolts.

[0021] A control method for a spacecraft solar array oscillation mechanism includes the following steps:

[0022] S1. The timer is reset to zero and starts timing. At the same time, the stepper motor enters the step-by-step acceleration operation phase.

[0023] S2. The step-by-step acceleration phase ends and the stepper motor enters the constant speed operation phase. Obtain the operating current of the stepper motor at this time. If the operating current is normal, proceed to step S3. Otherwise, if the operating current is abnormal, check if there is a usable backup winding. If there is a usable backup winding, mark the current operating winding of the stepper motor as unusable and switch to the backup winding. Proceed to step S1. If there is no usable backup winding, forcibly terminate the drive.

[0024] S3. After the constant speed operation phase ends, the stepper motor enters the step deceleration operation phase. When the motor speed decreases by the preset value, the step deceleration operation phase ends, and the stepper motor enters the low constant speed operation phase.

[0025] S4. Monitor the counter value. If the counter value is greater than the preset counting threshold, the drive will be forcibly terminated. Otherwise, the drive will terminate normally after receiving the bias signal.

[0026] Furthermore, the duration of the step-by-step acceleration phase is a preset constant value, the duration of the constant speed phase is a preset constant value, and the duration of the step-by-step deceleration phase is a preset constant value.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] (1) A control system applicable to the swing mechanism of a spacecraft is provided, which can accurately and reliably control the swing mechanism, monitor and eliminate the occurrence of faults within a certain limit, protect relevant equipment, and ensure the accuracy of the swing angle.

[0029] (2) The communication between the spacecraft host computer and the ground telemetry center is realized through the telemetry circuit module, which facilitates manual control and fault handling and ensures the reliability of the swing mechanism control.

[0030] (3) A control method for a swing mechanism is provided, which divides the swing process of the swing mechanism into a step-by-step acceleration, constant speed, step-by-step deceleration and low constant speed stage. The working current of the constant speed stage is detected to determine whether the motor is abnormal. Then, the counter count value and the bias signal are detected in the low constant speed stage. The drive can be forcibly terminated in case of abnormality to avoid damage to the motor. Attached Figure Description

[0031] Figure 1 A schematic diagram of a two-degree-of-freedom drive system for a spacecraft's solar cell array.

[0032] Figure 2A block diagram showing the hardware circuitry of the control system;

[0033] Figure 3 A flowchart of the control method;

[0034] Reference numerals: 01, spacecraft; 02, one-dimensional drive mechanism; 03, swing mechanism; 04, solar array.

[0035] 1. Spacecraft host computer; 2. Onboard power supply; 3. CPU control module; 4. Secondary power supply module; 5. Motor drive module; 6. Feedback signal processing module; 7. Drive backup switching module; 8a. +Y wing A / B winding backup switching module; 8b. -Y wing A / B winding backup switching module; 9a. +Y wing swing mechanism; 9b. -Y wing swing mechanism; 10. Telemetry circuit module. Detailed Implementation

[0036] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments. These embodiments are based on the technical solution of the present invention and provide detailed implementation methods and specific operating procedures. However, the scope of protection of the present invention is not limited to the following embodiments.

[0037] In the accompanying drawings, components with the same structure are indicated by the same numerical designation, and components with similar structures or functions are indicated by similar numerical designations. The dimensions and thicknesses of each component shown in the drawings are arbitrary, and the present invention does not limit the dimensions and thicknesses of each component. To make the illustrations clearer, some components are appropriately exaggerated in the drawings.

[0038] Example 1:

[0039] like Figure 1 As shown, the dual-degree-of-freedom drive device includes a one-dimensional drive mechanism 02 and a swing mechanism 03. In this embodiment, the one-dimensional drive mechanism 02 is mounted on the spacecraft 01, the swing mechanism 03 is mounted on the one-dimensional drive mechanism 02, and the solar cell array 04 is mounted on the swing mechanism 03. By adjusting the one-dimensional drive mechanism 02 and the swing mechanism 03, the solar cell array 04 can be oriented towards the sun.

[0040] The spacecraft 01 has solar cell arrays 04 installed on both sides, namely the +Y wing solar cell array and the -Y wing solar cell array. Therefore, there are two swing mechanisms 03, which are used to drive the ±Y wing solar cell arrays on the spacecraft 01. The power source of the swing mechanism 03 is a stepper motor. The stepper motor has two sets of windings, A and B, which are backups of each other. The step angle of the motor is 1.8°. The solar cell array 04 is equipped with an offset detection sensor to detect whether the solar cell array 04 has swung into position. After swinging into position, the offset detection sensor will send an offset position signal as a feedback signal.

[0041] A control system for a solar array oscillation mechanism on a spacecraft is provided. This system controls the oscillation mechanism 03, causing the solar array 04 to oscillate ±90 degrees around its axis. The controlled objects are two two-phase stepper motors mounted on the solar array 04 on both sides of the spacecraft 01. Figure 2 As shown, the control system includes a drive backup switching module 7, a telemetry circuit module 10, and two sets of circuits. The circuits include a CPU control module 3, a secondary power supply module 4, a motor drive module 5, a feedback signal processing module 6, and an A / B winding backup switching module.

[0042] CPU control module 3 is connected to the spacecraft host computer 1 and communicates with it via a serial communication port. It receives commands from the host computer 1 and controls the swing mechanism 03. Secondary power supply module 4 is connected to the 28V on-board power supply 2 on the spacecraft and converts the on-board power supply 2 on spacecraft 01 into the working voltage value required by various components in the control system. Motor drive module 5 is connected to CPU control module 3 and generates drive signals to the stepper motor based on the control commands of CPU control module 3, thereby driving the stepper motor to work. Feedback signal processing module 6 is connected to CPU control module 3 and preprocesses the feedback signal to convert it into a standard that the CPU module can accept before sending it to CPU control module 3. The feedback signal includes at least the stepper motor speed, working current, and the bias position signal of the solar cell array 04. A / B winding backup switching module is connected to CPU control module 3 and controls the switching of the stepper motor A / B windings based on the commands of CPU control module 3.

[0043] like Figure 2 As shown, one circuit includes a CPU control module 3, a secondary power supply module 4, a motor drive module 5, a feedback signal processing module 6, and a +Y wing A / B winding backup switching module 8a, used to control the +Y wing swing mechanism 9a; the other circuit includes a CPU control module 3, a secondary power supply module 4, a motor drive module 5, a feedback signal processing module 6, and a -Y wing A / B winding backup switching module 8b, used to control the -Y wing swing mechanism 9b.

[0044] The drive backup switching module 7 connects to the A / B winding backup switching modules of the two sets of lines. Based on the control commands of the spacecraft host computer 1, it controls the switching of the A / B windings of the stepper motor of the ±Y wing. After a failure of one line, the stepper motor can be controlled through the other line, which is more reliable. The telemetry circuit module 10 is used to realize the communication between the spacecraft host computer 1 and the ground telemetry center, so that the ground telemetry center can obtain relevant data, judge the working mode and working status of the swing mechanism 03, facilitate fault decision-making, and send the control commands to the spacecraft host computer 1 through the telemetry circuit module 10 to realize manual monitoring and adjustment.

[0045] The control system is a modular single-unit structure, consisting of multiple box-type structures. Each box-type structure includes an aluminum alloy shell, reinforcing crossbars, printed circuit boards, fasteners, and electronic components. All the box-type structures are connected together by 10 M5 titanium alloy long bolts, and the entire modular single unit is fixed to the spacecraft 01 satellite by 4 M5 bolts.

[0046] A control method for a spacecraft solar array oscillation mechanism, such as Figure 3 As shown, it includes the following steps:

[0047] S1. The timer is reset to zero and starts timing. At the same time, the stepper motor enters the step-by-step acceleration operation phase.

[0048] S2. The step-by-step acceleration phase ends and the stepper motor enters the constant speed operation phase. Obtain the operating current of the stepper motor at this time. If the operating current is normal, proceed to step S3. Otherwise, if the operating current is abnormal, check if there is a usable backup winding. If there is a usable backup winding, mark the current operating winding of the stepper motor as unusable and switch to the backup winding. Proceed to step S1. If there is no usable backup winding, forcibly terminate the drive.

[0049] S3. After the constant speed operation phase ends, the stepper motor enters the step deceleration operation phase. When the motor speed decreases by the preset value, the step deceleration operation phase ends, and the stepper motor enters the low constant speed operation phase.

[0050] S4. Monitor the counter value. If the counter value is greater than the preset counting threshold, the drive will be forcibly terminated. Otherwise, the drive will terminate normally after receiving the bias signal.

[0051] The duration of the step-by-step acceleration phase is a preset constant value, the duration of the constant speed phase is a preset constant value, and the duration of the step-by-step deceleration phase is a preset constant value.

[0052] In step S2, if an abnormal operating current of the stepper motor is detected, since the stepper motor contains two windings, A and B, the operating winding is switched to a backup winding to ensure the normal operation of the swing mechanism 03. This command is executed only once. If the operating current of the stepper motor becomes abnormal again, the winding switch will not be performed again because there is no available backup winding. If the operating current of the stepper motor returns to normal after switching the backup winding, the fault is resolved, and subsequent steps can continue. Otherwise, the stepper motor is damaged, and the drive is forcibly terminated.

[0053] In step S4, the stepper motor operates at a low constant speed. During this process, the system detects whether an external bias positioning signal is input and monitors the counter. If the bias positioning signal appears when the counter count is less than a predetermined threshold, it indicates that the solar array 04 has reached its swing position, the task is complete, and the drive ends normally. If the bias positioning signal does not appear even after the counter count exceeds the predetermined threshold, the drive is immediately forcibly stopped to ensure that the motor is not damaged during operation. At this point, two types of faults may occur in the control system.

[0054] a. Motor damaged. This is an unrepairable fault.

[0055] b. Solar array 04 failed to swing to the specified angle within the stipulated time. This is a repairable fault. The ground telemetry center obtains relevant data from the control system through telemetry circuit module 10 to determine whether the line is working properly. If the line cannot work properly, it can send a ground command through telemetry circuit module 10 to switch, and the spacecraft host computer 1 controls and drives the backup switching module 7 to restart.

[0056] This invention provides a control system applicable to spacecraft oscillation mechanisms, capable of precise and reliable control, monitoring and eliminating faults within certain limits, protecting relevant equipment, ensuring oscillation angle accuracy, and monitoring and providing feedback on angle and accuracy adjustments within certain limits. In case of abnormalities, it can actively switch windings or terminate the program. This invention reduces the development complexity of dual-degree-of-freedom drive devices and meets the solar orientation requirements of near-Earth spacecraft solar cell drive systems.

[0057] The preferred embodiments of the present invention have been described in detail above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A control method for a spacecraft solar array swing mechanism, characterized by, The method comprises the following steps: S1, the counter is cleared, and the stepping motor enters a step-by-step acceleration running stage; S2, the step-by-step acceleration running stage ends, the stepping motor enters a constant speed running stage, the working current of the stepping motor at this time is obtained, if the working current is normal, step S3 is executed, otherwise, the working current is abnormal, it is checked whether there is a backup winding available, if there is a backup winding available, the current working winding of the stepping motor is marked as unusable, and the backup winding is switched to, step S1 is executed, if there is no backup winding available, the driving is forcibly ended; S3, the constant speed running stage ends, the stepping motor enters a step-by-step deceleration running stage, and when the motor running speed is reduced to a preset value, the step-by-step deceleration running stage ends, and the stepping motor enters a low constant speed running stage; S4, the counting value of the counter is monitored, if the counting value of the counter is greater than a preset counting threshold, the driving is forcibly ended, otherwise, when a biasing to position signal is received, the driving is normally ended; The number of the swing mechanisms is 2, and the swing mechanisms are respectively used for driving ±Y wing solar cell arrays on the spacecraft. The swing mechanisms have stepping motors as power sources. The stepping motors have A and B groups of windings which are backup to each other. The solar cell arrays are provided with biasing detection sensors. The control system comprises a driving backup switching module and two groups of circuits. The circuits comprise a CPU control module, a motor driving module, a feedback signal processing module and an A / B winding backup switching module. The CPU control module is connected with an upper computer of the spacecraft. The motor driving module is connected with the CPU control module, generates a driving signal to the stepping motor based on a control instruction of the CPU control module. The feedback signal processing module is connected with the CPU control module, and feeds a preprocessed feedback signal into the CPU control module. The feedback signal at least comprises a rotating speed of the stepping motor, a working current and a biasing to position signal of the solar cell array. The A / B winding backup switching module is connected with the CPU control module, and controls switching of the stepping motor A / B winding based on an instruction of the CPU control module. The driving backup switching module is connected with the A / B winding backup switching modules of the two groups of circuits, and controls switching of the stepping motor A / B winding of the ±Y wing based on a control instruction of the upper computer of the spacecraft.

2. The control method for a spacecraft solar array swing mechanism according to claim 1, characterized by, The circuits further comprise a secondary power supply module, which converts a power source on the spacecraft into a working voltage value required by elements in the control system.

3. The control method for a spacecraft solar array swing mechanism according to claim 2, wherein The power source on the spacecraft is a 28V power source.

4. The method of claim 1, wherein, The CPU control module is connected with the upper computer of the spacecraft through a serial communication port.

5. The method of claim 1, wherein, The control system further comprises a telemetry circuit module, which is used for realizing communication between the upper computer of the spacecraft and a ground telemetry center.

6. The method of claim 1, wherein, The motor step angle of the stepping motor is 1.8°.

7. The method of claim 1, wherein, The control system is a modular single machine structure, comprises a plurality of box structures, the box structure comprises a shell, a reinforcing cross strip, a circuit printed board, a fastener and electronic components, and all the box structures are connected together and then installed on the spacecraft.

8. The method of claim 7, wherein, All the box structures are connected through long bolts, and the whole modular single machine is fixed on the spacecraft through bolts.

9. The method of claim 1, wherein, The duration of the stepwise acceleration operating phase is a pre-set constant value, the duration of the constant speed operating phase is a pre-set constant value, and the duration of the stepwise deceleration operating phase is a pre-set constant value.

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