Parameter self-adaptive control method for low-orbit satellite with solar panel driving device

Abstract

The invention discloses a parameter self-adaptive control method for a low-orbit satellite with a solar panel driving device. Belongs to the technical field of aerospace, and particularly relates to the technical field of low-orbit satellite parameter control. The satellite attitude control method solves the technical problems of overcoming the influence of the rotational inertia of the satellite and compensating the influence of the SADA vibration disturbance torque and the atmospheric resistance torque on the satellite attitude control precision. The method comprises the following steps: constructing a satellite attitude kinematics and dynamics equation in a quaternion form, and constructing a satellite attitude kinematics and dynamics equation for designing an attitude controller on the basis of the satellite attitude kinematics and dynamics equation; defining an error attitude kinematics and dynamics equation of the satellite through the attitude control error and the angle control error; carrying out segmentation conversion on a to-be-estimated parameter and a known state variable, and expressing the negative influence of a rotational inertia error on the attitude by matrix operation; designing the control torque of the attitude controller by adopting a mode of combining nonlinear feedback control with self-adaptive control; and updating the self-adaptive estimated value in the control parameters of the attitude controller by adopting a parameter self-adaptive law.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of aerospace, and particularly relates to the technical field of low-orbit satellite parameter control. BACKGROUND

[0002] With the rapid development of aerospace technology, the application of communication, navigation and remote sensing satellites is also more and more extensive. In order to improve the working efficiency of the satellite, many satellites are equipped with a solar array drive assembly (SADA), which can control the solar array to always point to the sun under different orbits and attitudes, ensure the energy balance of the satellite, and enhance the adaptability of the task. However, since the SADA drives the solar array to rotate at different angles, the moment of inertia of the satellite is also changing in real time. At the same time, the SADA will generate a reaction force acting on the satellite body during acceleration and deceleration, which seriously affects the attitude stability of the satellite. In addition, due to the increase of solar activity, the satellite in low-orbit also faces serious atmospheric drag torque, which brings great challenges to the realization of high-precision pointing control. SUMMARY

[0003] In order to solve the technical problem of overcoming the influence of the moment of inertia of the satellite and compensating the influence of the SADA disturbance torque and the atmospheric drag torque on the attitude control accuracy of the satellite, the application provides a low-orbit satellite parameter adaptive control method with a solar array drive assembly. Through dynamic parameter adaptive estimation, the moment of inertia parameters and disturbance torques of the satellite can be estimated in real time, and compensation is performed in combination with nonlinear control. Finally, the satellite can balance the task execution efficiency and control accuracy.

[0004] The method provided by the application comprises the following steps: S1, satellite attitude kinematics and dynamics modeling: constructing a satellite attitude kinematics and dynamics equation in quaternion form, and constructing a satellite attitude kinematics and dynamics equation for attitude controller design on this basis; S2, error attitude kinematics and dynamics equation modeling: defining the error attitude kinematics and dynamics equation of the satellite through attitude control error and angle control error; S3, moment of inertia error matrix transformation: defining a transformation function to separate and convert the to-be-estimated parameters and known state variables, and representing the negative influence of the moment of inertia error on the attitude by matrix operation; S4, attitude controller calculation: designing an attitude controller control torque by adopting a nonlinear feedback control combined with adaptive control; S5, attitude controller parameter adaptive law design: updating the adaptive estimation value in the attitude controller control parameter by adopting a parameter adaptive law.

[0005] Further, the satellite attitude kinematics and dynamics equation in quaternion form is specifically constructed as follows: Using attitude quaternions To represent the satellite's body coordinate system Relative to the inertial coordinate system The posture, among which Representing the scalar part of a quaternion. The vector part of a quaternion. express The transpose of , and satisfies the constraints. ; The quaternion form of the satellite attitude kinematics equations is: ; The quaternion form of the satellite attitude dynamics equations is: ; in, The matrix representing the satellite's moment of inertia; Indicates the satellite's attitude angular velocity; This represents the control angular momentum of the reaction flywheel; This represents the sum of the vibration disturbance torque and the atmospheric drag torque of the SADA. This indicates the control torque of the reaction flywheel; They represent The differential; Representing vectors The antisymmetric matrix; express identity matrix; express The differential; express antisymmetric matrix, subscript These represent the satellite's rotation axes.

[0006] Furthermore, the specific kinematic equations for satellite attitude control design are as follows: The kinematic equations for satellite attitude control design are: ; The satellite attitude dynamics equations used for attitude controller design are: ;in, The matrix representing the measured moment of inertia of the satellite. .

[0007] Furthermore, the satellite is defined in the inertial coordinate system. Expected posture quaternion Attitude control error is expressed by error quaternion. express, , Represents the expected quaternionthe inverse of , denotes quaternion multiplication; , denotes the error quaternion scalar part of denotes the error quaternion vector part of defines the desired angular velocity of the satellite in the inertial coordinate system , the angular velocity control error is represented by the error angular velocity , ; denotes the rotation transformation matrix of the error quaternion ; denotes the skew-symmetric matrix of the vector .

[0008] Further, the error attitude kinematics dynamics equation of the satellite is specifically: the error attitude kinematics equation of the satellite: ; the error attitude dynamics equation of the satellite: .

[0009] Further, step S3 is specifically defined as: defining a transformation function , given the vector , , there is the following relationship: ; The to-be-estimated parameters are segmented and converted with the known state variables, that is: , , , ; Finally, the negative influence of the rotational inertia error on the attitude is represented by .

[0010] Further, the control torque of the attitude controller is obtained by:

[0011] ; denotes the proportional control gain; denotes the differential control gain; denotes the nonlinear compensation control: denotes an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque.

[0012] Further, the step S5 is specifically: an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque; an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque, an adaptive estimation value of the external disturbance torque for compensating the influence of the external disturbance torque, .

[0013] The method has the following beneficial effects: (1) The inertia time-varying parameter and the external disturbance torque parameter can be estimated in real time through the parameter adaptive estimation, and the controller is reconfigured to compensate the influence of the inertia parameter error and the disturbance torque on the attitude pointing precision and the attitude stability.

[0014] (2) The attitude control precision of the low-orbit satellite with the solar panel driving device is ensured, and a technical foundation is provided for the satellite to successfully perform the stable communication task and the high-quality remote sensing imaging task.

[0015] (3) The designed method is simple in regulation and control, high in economic value, and suitable for the attitude control system design of the low-orbit satellite, especially the high-precision optical remote sensing satellite. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 is a control method architecture diagram in the embodiment of the application; Figure 2 is an attitude quaternion curve diagram in the embodiment of the application; Figure 3 is an attitude angular velocity curve diagram in the embodiment of the application; Figure 4 is an error quaternion curve diagram in the embodiment of the application; Figure 5 is an error angular velocity curve diagram in the embodiment of the application; Figure 6 is an interference torque parameter estimation curve diagram in the embodiment of the application; Figure 7 is an inertia parameter estimation curve diagram in the embodiment of the application. DETAILED DESCRIPTION

[0017] The technical solutions of the present application will be described clearly and completely in combination with the drawings. Obviously, the described embodiments are part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the protection scope of the present application.

[0018] The overall architecture of the method described in the present application is shown in Figure 1 Based on the basic feedback control method, the nonlinear feedback control is added to enhance the tracking performance of the attitude control. At the same time, the parameter adaptive compensation control is introduced to compensate the influence of the time-varying moment of inertia parameter and external disturbance torque on the attitude control accuracy.

[0019] The present application is realized by the following technical solutions. The low-orbit satellite parameter adaptive control method with solar sail driving device comprises the following steps: Step 1, satellite attitude kinematics and dynamics modeling: The attitude control reference of the satellite in orbit for space task is the geocentric inertial coordinate system , and the body coordinate system . In order to describe the full-dimensional attitude change without singularity, the attitude quaternion is used to represent the attitude of the satellite body coordinate system relative to the inertial coordinate system , wherein represents the scalar part of the quaternion, represents the vector part of the quaternion, represents the transpose of , and satisfies the constraint condition . The satellite attitude kinematics and dynamics equations in the form of quaternion are as follows: The satellite attitude kinematics equation in the form of quaternion is: ; and the satellite attitude dynamics equation in the form of quaternion is: ; wherein: represents the moment of inertia matrix of the satellite; represents the satellite attitude angular velocity; represents the control angular momentum of the reaction flywheel; represents the sum of the disturbance torque of SADA and the atmospheric resistance torque; represents the control torque of the reaction flywheel; respectively represent the differential of ; represents the skew-symmetric matrix of the vector ; represents the unit matrix of ; denotes the differential of denotes the skew-symmetric matrix of where In particular, The real inertia of the satellite is where the subscripts denote the rotation axes of the satellite, and the measured inertia is defined as The error between the measured inertia and the real inertia is Since only the measured inertia can be obtained in practical engineering, the satellite attitude kinematics and dynamics equation used for controller design can be described as The above equation can be simplified as Step 2, error attitude kinematics and dynamics equation modeling: Define the desired attitude quaternion of the satellite in the inertial coordinate system The attitude control error can be represented by the error quaternion whose calculation formula is as follows: where: denotes the inverse of the desired quaternion denotes quaternion multiplication.

[0020] Define the desired angular velocity of the satellite in the inertial coordinate system The angular velocity control error can be represented by the error angular velocity whose calculation formula is as follows: where denotes the rotation transformation matrix of the quaternion, and its calculation formula is: where: denotes the skew-symmetric matrix of the vector

[0021] Combining the above, the error attitude kinematics and dynamics equation of the satellite is: .​​​​​​​​​​​​​​

[0022] Step 3, Transformation of the moment of inertia error matrix: To design a parameter adaptive controller, a new transformation function is defined. If given vector The following relationship exists: ; The parameters to be estimated are separated and transformed from the known state variables, that is:

[0023] in: ; ; ; Ultimately, the negative impact of rotational inertia error on attitude can be attributed to matrix operations. . Step 4, Attitude Controller Design: To ensure the excellent performance of the attitude tracking controller, a combination of nonlinear feedback control and adaptive control is used in the controller design. The specific form of the attitude controller is as follows: ; in: This indicates that the control torque calculated by the controller is sent to the reaction flywheel (actuator).

[0024] Indicates proportional control gain; Indicates the differential control gain; Indicating nonlinear compensation control: express The adaptive estimate is used to compensate for the influence of external disturbance torque; express An adaptive estimate is used to compensate for the time-varying effects of the moment of inertia.

[0025] Step 5, Parameter Adaptive Law Design: To dynamically compensate for the effects of external disturbance torques and time-varying moments of inertia, real-time calculations are required. and This enables real-time compensation for factors affecting attitude control accuracy. and The parameter adaptive law is used for updating the estimate, specifically in the form of: The update was successful using the parameter adaptive law: To carry out, on The update was successful using the parameter adaptive law: conduct, denotes the update gain of the adaptive law; denotes the derivative of the estimated parameter ; denotes the correction gain of the adaptive law, denotes the error angular velocity loop control variable, . Wherein: denotes the update gain of the adaptive law; denotes the derivative of the estimated parameter ; denotes the correction gain of the adaptive law.

[0026] The control method of the embodiment adds the scene of the imaging process through two attitude maneuver control processes, to illustrate the attitude control performance of the method. The analysis process is a total of 200s, wherein 0s-50s is the initial attitude stabilization process, 50s attitude starts to maneuver, 80s-120s is the first earth imaging process; 120s after the second attitude maneuver, 160s-200s is the second earth imaging process. The attitude quaternion control curve is shown in Figure 2 , from which it can be observed that the actual attitude curve and the expected attitude curve are basically completely coincided, which illustrates the excellent attitude tracking control performance. The attitude angular velocity control curve is shown in Figure 3 , the attitude maneuver angular velocity curve is approximately a triangle, which illustrates that the attitude maneuver process converges rapidly. The attitude quaternion control error and the angular velocity control error are shown in Figures 4-5 , the attitude control error of the satellite throughout the process is very small, and the control error quickly completes the convergence. The disturbance torque and the moment of inertia estimated parameter are shown in Figures 6-7 , which rapidly adaptively adjusts the parameter estimation value with the change of the satellite state, ensuring accurate control precision.

[0027] The embodiment related parameters are shown in Table 1.

[0028] Table 1:

[0029] The memory in the embodiments of the application can be a volatile memory or a nonvolatile memory, or can include both volatile and nonvolatile memory. Among them, the nonvolatile memory can be a read only memory (read only memory, ROM), a programmable read only memory (programmable ROM, PROM), an erasable programmable read only memory (erasable PROM, EPROM), an electrically erasable programmable read only memory (electrically EPROM, EEPROM) or a flash memory. The volatile memory can be a random access memory (random access memory, RAM) used as an external cache. By way of example, but not limitation, many forms of RAM are available, such as static random access memory (static RAM, SRAM), dynamic random access memory (dynamic RAM, DRAM), synchronous dynamic random access memory (synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (double data rate SDRAM, DDR SDRAM), enhanced synchronous dynamic random access memory (enhanced SDRAM, ESDRAM), synchronous link dynamic random access memory (synchlink DRAM, SLDRAM) and direct memory bus random access memory (direct rambus RAM, DR RAM). It should be noted that the memory of the method described in the present application is intended to include but not limited to these and any other suitable type of memory.

[0030] In the above embodiments, all or part of the embodiments can be implemented by software, hardware, firmware or any combination thereof. When implemented by software, all or part of the embodiments can be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer instructions are loaded and executed on a computer, all or part of the processes or functions described in the embodiments of the present application are generated. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium or transferred from one computer-readable storage medium to another computer-readable storage medium, for example, the computer instructions can be transferred from one website, computer, server or data center to another website, computer, server or data center through wired (such as coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (such as infrared, wireless, microwave, etc.) manner. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device such as a server, data center, etc. integrated with one or more available media. The available media can be magnetic media (such as floppy disk, hard disk, magnetic tape), optical media (such as high-density digital video disc (digital video disc, DVD)), or semiconductor media (such as solid state disc (solid state disc, SSD)) and the like.

[0031] In the implementation process, each step of the above method can be completed by integrated logic circuit of hardware in the processor or instruction in the form of software. The steps of the method disclosed in the embodiments of the present application can be directly embodied as hardware processor execution or executed by combination of hardware and software modules in the processor. The software module can be located in random access memory, flash memory, read-only memory, programmable read-only memory, electrically erasable programmable memory, register or other mature storage medium in the art. The storage medium is located in the memory, and the processor reads the information in the memory and combines the hardware to complete the steps of the above method. To avoid repetition, it will not be described in detail here.

[0032] It should be noted that the processor in the embodiments of the present application can be an integrated circuit chip with a signal processing capability. In the implementation process, each step of the method embodiments can be completed by an integrated logic circuit or an instruction in the form of software in the processor. The processor mentioned above can be a general processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. Each method, step and logic block diagram disclosed in the embodiments of the present application can be implemented or executed. The general processor can be a microprocessor or the processor can also be any conventional processor. The steps of the method disclosed in conjunction with the embodiments of the present application can be directly embodied as a hardware code processor for execution, or a combination of hardware and software modules in the code processor for execution. The software module can be located in a random access memory, a flash memory, a read only memory, a programmable read only memory or an electrically erasable programmable memory, a register or other mature storage medium in the art. The storage medium is located in the memory, and the processor reads the information in the memory, and combines the hardware to complete the steps of the above method.

Claims

1. A method for adaptive control of low-Earth orbit satellite parameters with a solar panel drive device, characterized in that, The method includes the following steps: S1. Perform satellite attitude kinematics and dynamics modeling: Construct satellite attitude kinematics and dynamics equations in quaternion form, and on this basis, construct satellite attitude kinematics and dynamics equations for attitude controller design; S2. Model the error attitude kinematics and dynamics equations: Define the error attitude kinematics and dynamics equations of the satellite by using attitude control error and angle control error; S3. Perform rotational inertia error matrix transformation: Define a transformation function to separate and transform the parameters to be estimated with the known state variables, and represent the negative impact of rotational inertia error on attitude using matrix operations; S4. Perform attitude controller design: Design the attitude controller control torque using a combination of nonlinear feedback control and adaptive control. S5. Design the adaptive law for attitude controller parameters: Update the adaptive estimates in the attitude controller control parameters using the adaptive law.

2. The low-Earth orbit satellite parameter adaptive control method with solar panel drive device according to claim 1, characterized in that, The quaternion form of the satellite attitude kinematics and dynamics equations are constructed as follows: Using attitude quaternions To represent the satellite's body coordinate system Relative to the inertial coordinate system The posture, among which Representing the scalar part of a quaternion. The vector part of a quaternion. express The transpose of , and satisfies the constraints. ; The quaternion form of the satellite attitude kinematics equations is: ; The quaternion form of the satellite attitude dynamics equations is: ; in, The matrix representing the satellite's moment of inertia; Indicates the satellite's attitude angular velocity; This represents the control angular momentum of the reaction flywheel; This represents the sum of the vibration disturbance moment and the atmospheric drag moment of the SADA. This indicates the control torque of the reaction flywheel; They represent The differential; Representing vectors The antisymmetric matrix; express identity matrix; express The differential; express antisymmetric matrix, subscript These represent the satellite's rotation axes.

3. The low-orbit satellite parameter adaptive control method with solar panel drive device according to claim 2, characterized in that, The specific kinematic equations for satellite attitude kinematics used in attitude controller design are as follows: The kinematic equations for satellite attitude control design are: ； The satellite attitude dynamics equations used for attitude controller design are: ;in, The matrix representing the measured moment of inertia of the satellite. .

4. The low-Earth orbit satellite parameter adaptive control method with solar panel drive device according to claim 3, characterized in that, Define the satellite in the inertial coordinate system Expected posture quaternion Attitude control error is expressed by error quaternion. express, , Represents the expected quaternion The reverse, Represents quaternion multiplication; , Representing error quaternions The scalar part, Representing error quaternions Vector part, Define the satellite in the inertial coordinate system Expected angular velocity Angular velocity control error is achieved through error angular velocity. express, ; The rotation transformation matrix representing the error quaternion. ; Representing vectors An antisymmetric matrix.

5. The low-Earth orbit satellite parameter adaptive control method with solar panel drive device according to claim 4, characterized in that, The specific equations of motion for the satellite's attitude error are as follows: The error attitude kinematic equations of the satellite: Satellite error attitude dynamics equations: 。 6. The low-Earth orbit satellite parameter adaptive control method with solar panel drive device according to claim 5, characterized in that, Step S3 specifically involves defining the transformation function. Given vector The following relationship exists: ； The parameters to be estimated are separated and transformed from the known state variables, that is: ， ， ， ； Finally, the negative impact of rotational inertia error on attitude was expressed using... express.

7. The low-Earth orbit satellite parameter adaptive control method with solar panel drive device according to claim 6, characterized in that, Control torque of attitude controller pass: get; Indicates proportional control gain; Indicates the differential control gain; Indicating nonlinear compensation control: express The adaptive estimate is used to compensate for the influence of external disturbance torque; express An adaptive estimate is used to compensate for the time-varying effects of the moment of inertia.

8. The low-Earth orbit satellite parameter adaptive control method with solar panel drive device according to claim 7, characterized in that, Step S5 is as follows: right The update was successful using the parameter adaptive law: To carry out, on The update was successful using the parameter adaptive law: conduct, Represents the update gain of the adaptive law; Represents the estimated parameters The derivative; This represents the correction gain of the adaptive law. This represents the error angular velocity loop control variable. .

9. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1-8.

10. A computer-readable storage medium for storing computer instructions, characterized in that, When the computer instructions are executed by the processor, they implement the steps of the method according to any one of claims 1-8.

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