Aircraft output feedback attitude control method
By designing an angular velocity observer using a modified Rodrigues parameter framework and an immersion and invariant method, and combining it with a filtered state and a proportional-derivative feedback controller, the problem of unmeasurable angular velocity of the aircraft was solved, achieving high-precision attitude control and simplifying the observer structure.
Patent Information
- Application Number
- CN202511528792.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-24
- Publication Date
- 2026-01-16
AI Technical Summary
Existing technologies for measuring the angular velocity of aircraft suffer from accuracy issues due to sensor defects, external environmental interference, and the characteristics of the aircraft itself, making it difficult to achieve high-precision attitude control. In particular, when angular velocity information is unmeasurable, existing methods suffer from low accuracy and high complexity.
An angular velocity observer is designed using a modified Rodrigues parameter framework and an immersion and invariant method. By introducing a filtered state and a proportional-differential feedback controller, the observer structure is simplified, the observation accuracy is improved, and the computational load is reduced.
It achieves high-precision attitude control when angular velocity is unmeasurable, simplifies the observer structure, reduces computational complexity, and improves the parameter adjustment range and the practicality of the observer.
Smart Images
Figure CN121349136A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of rigid body aircraft attitude control, and particularly relates to an aircraft output feedback attitude control method and device, medium and equipment. BACKGROUND
[0002] In application scenarios such as satellites, unmanned aerial vehicles, spacecraft, underwater vehicles and robot manipulators involving rigid body attitude control, accurate angular velocity measurement is the key to achieving high-precision attitude control. However, current aircrafts face many challenges in angular velocity measurement, which is mainly due to three factors: sensor defects, external environmental interference and aircraft characteristics. In terms of sensor defects, for example, MEMS sensors, temperature changes will significantly affect their sensitivity. In extreme temperature differences, the characteristics of fiber-optic gyroscopes will also change, thereby affecting the measurement results, and the precision is limited. In terms of external environmental interference, temperature fluctuations will cause sensor zero drift and sensitivity changes. Vibration and impact caused by engine vibration, airflow impact and other factors during flight not only produce instantaneous measurement interference, but also reduce measurement accuracy in the long run, and even cause the sensor to fail. In terms of aircraft characteristics, in order to control costs, many aircrafts do not have sensors. Although this measure reduces hardware costs and subsequent maintenance costs, it makes the angular velocity measurement, which is already difficult, even more difficult, further increasing the difficulty of achieving high-precision attitude control.
[0003] There are mainly three methods to solve the problem of unmeasurable angular velocity. The first method is to use Kalman filtering and its derivative algorithms for online estimation of angular velocity. When this method is used in the aircraft attitude control system, the algorithm is often simplified to different degrees, greatly reducing the accuracy of angular velocity estimation. The second method is based on the research of the passivity characteristics of the attitude dynamics model. However, this method has certain limitations. It cannot directly provide angular velocity estimates, which is a problem in some applications that require angular velocity information, such as high-speed maneuvering aircraft attitude adjustment tasks. Accurate real-time angular velocity information is crucial for quickly responding to external disturbances and maintaining flight stability. The lack of angular velocity estimates will cause attitude control to be delayed and deviated. The third method is to design an angular velocity observer. However, it is very complex to design an observer for nonlinear time-varying rigid body dynamics. The establishment of separation properties and the demonstration of closed-loop system stability are two major difficulties in existing angular velocity observer design methods, which severely limit the application of related observer methods.
[0004] The observers designed using the immersion and invariance method can solve the above problems well. However, the current angular velocity observers designed based on the immersion and invariance method all use quaternions to describe the attitude, and the designed observers contain quite complex dynamic scaling factors, which makes the observer structure complex and computationally intensive, which is not conducive to practical applications. Summary of the Invention
[0005] Therefore, it is necessary to provide an aircraft output feedback attitude control method, device, medium, and equipment to address the aforementioned technical problems.
[0006] The following technical solution is adopted in this specification: This specification provides a method for output feedback attitude control of an aircraft, including: Based on the modified Rodrigues parameter framework, the attitude kinematics model and dynamics model of the aircraft are established. Based on the attitude kinematics model and dynamics model, and combined with the principles of immersion and invariance, the external form of the angular velocity observer is designed; wherein, the external form of the observer includes dynamic update terms and compensation terms; Based on the external form of the angular velocity observer, the specific functional expression of the angular velocity observer is obtained by introducing the filtering state of the angular velocity observation value; Based on the specific function expression of the angular velocity observer and the proportional-differential full feedback attitude controller, the output feedback attitude control law based on the angular velocity observer is obtained. According to the aforementioned feedback attitude control law, attitude control is performed on an aircraft whose angular velocity information is unmeasurable.
[0007] Furthermore, the process of establishing the attitude kinematics model and dynamics model of the aircraft specifically includes: Using modified Rodrigues parameters, the attitude kinematics and dynamics equations of a single-unit aircraft are established: ; ; in, It corrects the Rodrigues parameters; yes The derivative; It is the angular velocity of the aircraft; It is the derivative of the aircraft's angular velocity; It is the cross product matrix corresponding to the angular velocity of the aircraft; It is the control torque; It is the moment of inertia; To correct the attitude transfer matrix represented by the Rodrigues parameters.
[0008] Furthermore, the angular velocity observation values of the angular velocity observer The calculation formula is: ; in, It is a dynamically updated item; It is the moment of inertia; It corrects the Rodrigues parameters; It is a compensation item β Other states included in it; It is a compensation item; By introducing the filtered state of the attitude value, the partial differential equation concerning the compensation term is solved approximately, and the external form of the compensation term is obtained.
[0009] Furthermore, the specific functional expression of the angular velocity observer is calculated as follows: Based on the external form of the angular velocity observer, a filter state with modified Rodrigues parameters is introduced. Alternative Solve the partial differential equation of the compensation term to obtain the compensation term. β The function expression; By introducing the filtering state of angular velocity observations The nonlinear compensation error in the system is suppressed to obtain the filtered state of the angular velocity observations; Based on the filtered state of the angular velocity observations, the control parameters are obtained. and dynamic update items The function expression; The solution to the partial differential equation for the compensation term is as follows: ; in, These are control parameters; To correct the Rodrigues parameters The filtering state; β As compensation; Dynamic definition: ; in, These are control parameters; It is the filtering error; To correct the attitude transfer matrix represented by the Rodrigues parameters; These are observed angular velocities. The dynamic design function for the filtering state of the angular velocity observations is: ; in, Angular velocity observation value The filtering state; for The derivative; It is the control torque; The control parameters The function expression is: ; in, It is a positive number; It is the moment of inertia. The largest eigenvalue; For any small positive constant; The dynamic update item The function expression is: ; in, It is the moment of inertia; yes Derivative; yes Derivative.
[0010] Specifically, the aircraft output feedback attitude control method of the present invention further includes proving the global exponential convergence of the observation error of the angular velocity observer by designing a dynamic scaling factor and a candidate Lyapunov function.
[0011] Furthermore, the proof process for the global exponential convergence of the observation error of the angular velocity observer specifically includes: By defining the scaling error of the angular velocity observation, the derivative of the scaling factor r is obtained; For each parameter of the scaling error formula, four candidate Lyapunov functions are designed; By analyzing the candidate Lyapunov function and its corresponding derivative, it is proven that the system is exponentially convergent. The scaling error of the angular velocity observation is defined as: ; in, Z This is the error in scaling angular velocity observation; It is an error in angular velocity observation; r It is the scaling factor; The scaling factor r The derivative of is calculated using the following formula: ; in, It is a positive number; It is the smallest eigenvalue of the inertia matrix; Moment of inertia The 2-norm; These are observed angular velocities. for The filtering state; The four candidate Lyapunov functions are: ; ; ; ; in, It is the filtering error; This is the filtering error of the angular velocity observations; The filtering error of the angular velocity observation is defined as: .
[0012] Furthermore, the obtained output feedback attitude control law based on the angular velocity observer specifically includes: The proportional-derivative tracking controller is designed as follows: ; in, , It is a positive number; It is the angular velocity of the aircraft; It is the cross product matrix corresponding to the angular velocity of the aircraft; It is the control torque; It is the moment of inertia; It corrects the Rodrigues parameters; The angular velocity observation value of the angular velocity observer Replace the aircraft angular velocity in the proportional-derivative tracking controller The value of is used to obtain the output attitude control law based on the angular velocity observer: ; in, These are the observed angular velocity values.
[0013] The above-mentioned technical solutions adopted in this specification can achieve the following beneficial effects: This invention employs an immersion and invariant method to design an angular velocity observer, which can accurately capture the angular velocity of an aircraft, greatly improving observation accuracy. By introducing filters that correct Rodrigues parameters and angular velocity observation values, the integrability barrier of immersion and invariance methods and the disturbance problem caused by nonlinear term compensation in the dynamic equations are overcome. Through reasonable design of the dynamic scaling factor, the scaling factor is only used to assist in the stability proof of the system, and no scaling factor is needed in the controller. This further simplifies the complexity and computational load of existing immersion and invariant angular velocity observers, enhances the adjustability and practicality of the observer parameters, and enables attitude control when the angular velocity of the aircraft is unmeasurable. Attached Figure Description
[0014] The accompanying drawings, which are included to provide a further understanding of this application and form part of this application, illustrate exemplary embodiments of this application and are used to explain this application, but do not constitute an undue limitation of this application. In the drawings:
[0015] Figure 1 This specification provides a flowchart illustrating an aircraft output feedback attitude control method. Figure 2 This is a closed-loop structural diagram of an aircraft attitude control system provided in this specification. Detailed Implementation
[0016] To make the objectives, technical solutions, and advantages of this specification clearer, the technical solutions of this application will be clearly and completely described below in conjunction with specific embodiments and corresponding drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. All other embodiments obtained by those skilled in the art based on the embodiments in this specification without creative effort are within the scope of protection of this application.
[0017] This invention provides an output feedback attitude control method for aircraft, aiming to solve the attitude control problem of aircraft when angular velocity is unmeasurable. The method employs an aircraft attitude motion model described by modified Rodrigues parameters and designs an angular velocity observer based on the immersion and invariance method. This effectively addresses the problem of low angular velocity estimation accuracy in existing methods when angular velocity is unmeasurable. By introducing filtered states to solve the disturbance problems caused by integrability barriers and nonlinear term compensation, the method avoids the problems of high computational burden and complex controller design in existing methods. Furthermore, the observer does not require scaling factor information, further reducing its complexity and improving the parameter adjustment range.
[0018] In order to achieve the objectives of the present invention, the technical solutions provided by the various embodiments of this application will be described in detail below with reference to the accompanying drawings.
[0019] Figure 1 This is a flowchart illustrating an aircraft output feedback attitude control method as described in this specification, which specifically includes the following steps: S101: Establish the attitude kinematics and dynamics model of the aircraft within the modified Rodrigues parameter framework.
[0020] Under the modified Rodrigues parameter framework, the individual attitude motion model of the aircraft is as follows: ; ; in, It corrects the Rodrigues parameters; It is the angular velocity of the aircraft; It is the derivative of the aircraft's angular velocity; It is the cross product matrix corresponding to the angular velocity of the aircraft; It is the control torque; It is the moment of inertia; To correct the attitude transfer matrix represented by the Rodrigues parameters, it is defined as: ; in, Denotes the cross product matrix for any vector. ,have ;in It is an antisymmetric matrix.
[0021] S102: Design an angular velocity observer using the immersion and invariance method, and approximate the solution of the partial differential equation.
[0022] Based on the principles of immersion and invariance, the angular velocity observer takes the following form: in, These are observed values of angular velocity; It is a dynamically updated item; It is the system's undetermined state function; and The specific form is yet to be designed.
[0023] The angular velocity parameter estimation error is defined as... .
[0024] To obtain the specific form of the angular velocity observer, it is necessary to overcome the integrability barrier of the partial differential equations. Therefore, by providing... Introducing filter state Substitution, approximate solution of partial differential equations ,in The dynamic definition is: ; in, It is a positive number; The specific form is yet to be determined; Define the attitude filtering error as: .
[0025] S103: Introducing the observer filter state to overcome the disturbance caused by nonlinear compensation, and giving the specific form of the observer.
[0026] By providing Introducing filter state To handle the additional disturbances caused by nonlinear term compensation, The dynamic design is as follows: ; Define the observation filtering error as .
[0027] With the help of , and thus and The specific form is as follows: ; ; in, It is a positive number; Inertia matrix The 2-norm; For any small positive constant; yes Derivative; yes Derivative; yes The derivative of .
[0028] S104: Design the Lyapunov function and dynamic scaling factor, and prove the global exponential convergence of the angular velocity observation error.
[0029] To prove the stability of the closed-loop system, the scaling error is defined as: in, ; It is a positive number; The smallest eigenvalue of the inertia matrix; note that... , Established.
[0030] Design the following four candidate Lyapunov functions: ; ; ; ; Based on the positive definiteness of the candidate Lyapunov function and the semi-negative definiteness of its derivative, combined with the correlation between the two, it can be determined that the angular velocity observation error has global exponential convergence, and the dynamic scaling factor is only used to assist in the stability proof, and no scaling factor information is needed in the observer.
[0031] S105: A proportional-differential output feedback attitude controller designed by combining immersion and constant angular velocity observers.
[0032] The proportional-derivative tracking controller used is designed as follows: ; in , It is a positive number.
[0033] By combining the angular velocity observer with the full-state feedback attitude tracking control law, the designed output attitude control law based on the angular velocity observer is as follows: S106: Provides the complete form of the controller, applicable to attitude control systems where angular velocity is unmeasurable.
[0034] Summarizing the results of the above steps, the complete form of the designed aircraft attitude controller is as follows: The aforementioned controller is used in the aircraft attitude motion control system to achieve attitude control when the angular velocity is unmeasurable. The resulting closed-loop structure diagram of the aircraft attitude control system is shown below. Figure 2 As shown.
[0035] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.
Claims
1. An aircraft output feedback attitude control method, characterized by, The application relates to a method for designing an output feedback attitude control law based on an angular velocity observer. The application comprises the following steps: According to the attitude kinematics model and the dynamics model, the external form of an angular velocity observer is designed by combining the immersion and invariance principle; wherein the external form of the observer comprises a dynamic updating term and a compensation term; Based on the external form of the angular velocity observer, a specific function expression of the angular velocity observer is obtained by introducing a filtering state of the angular velocity observation value; According to the specific function expression of the angular velocity observer and a proportional-differential type full feedback attitude controller, an output feedback attitude control law based on the angular velocity observer is obtained; According to the feedback attitude control law, an attitude of an aircraft with unmeasurable angular velocity information is controlled.
2. The aircraft output feedback attitude control method of claim 1, wherein, The establishment process of the attitude kinematics model and the dynamics model of the aircraft comprises the following steps: The attitude kinematics equation and the dynamics equation of a single aircraft are established by using modified Rodrigues parameters; ； ； wherein is a modified Rodrigues parameter; is a derivative of is an angular velocity of the aircraft; is a derivative of the angular velocity of the aircraft; is a skew-symmetric matrix corresponding to the angular velocity of the aircraft; is a control torque; is a moment of inertia; is an attitude transition matrix expressed in terms of a modified Rodrigues parameter.
3. The aircraft output feedback attitude control method of claim 1, wherein the angular velocity observer The calculation formula is: ； wherein, is a dynamic update term; is a moment of inertia; is a modified Rodrigues parameter; is a compensation term β other states contained in the middle; is a compensation term; The filtering state of the attitude value is introduced to approximately solve a partial differential equation about the compensation term, and the external form of the compensation term is obtained.
4. The aircraft output feedback attitude control method of claim 1, wherein The calculation process of the specific function expression of the angular velocity observer is as follows: According to the external form of the angular velocity observer, by introducing the filtering state of the modified Rodrigues parameters substitute , the partial differential equation of the compensation term is solved, and the functional expression of the compensation term is obtained β ; Filtering state of angular velocity observation by introducing angular velocity observation Nonlinear compensation error in the system is suppressed to obtain the filtering state of angular velocity observation; a function expression of the control parameters depending on the filtered state of the angular velocity observation and the dynamic update term The solving result of the partial differential equation of the compensation term is as follows: ； wherein is a control parameter; is a filter state for the modified Rodrigues parameters ; β is a compensation term; is dynamically defined as: ； wherein is a control parameter; is a filtered error; is a modified Rodrigues parameter representation of the attitude transition matrix; is an angular velocity observation; The dynamic design function of the filtering state of the angular velocity observation value is as follows: ； wherein, is an angular velocity observation of the filtered state; is a derivative of ; and is a control moment; The control parameter The function expression of the control parameter is: ； wherein is a positive constant; is the maximum eigenvalue of the moment of inertia ; and is an arbitrarily small positive constant. The dynamic update item The function expression of the dynamic update item is: ； wherein, is the moment of inertia; is derivative; is derivative.
5. The aircraft output feedback attitude control method of claim 1, wherein, The application further comprises the following steps:
6. The aircraft output feedback attitude control method of claim 5, wherein, The global exponential convergence of the observation error of the angular velocity observer is proved by designing a dynamic scaling factor and candidate Lyapunov functions. The proof process of the global exponential convergence of the observation error of the angular velocity observer comprises the following steps: The derivative of the scaling factor r is obtained by defining the scaling error of the angular velocity observation value; Four candidate Lyapunov functions are designed for the parameters of the scaling error formula respectively; The system is proved to be exponentially convergent by analyzing the candidate Lyapunov functions and the corresponding derivatives; ； wherein, Z is a scaled angular velocity observation error; is an angular velocity observation error; r is a scaling factor; The scaling factor r The derivative of the scaling factor, calculated as: ； wherein, is a normal number; is the smallest eigenvalue of the inertia matrix; is the 2-norm of the moment of inertia is the angular velocity observation; is the filtered state of is the filtered state of is the filtered state of The scaling error of the angular velocity observation value is defined as follows: ； ； ； ； wherein, is the filtered error; is the filtered error of the angular velocity observation; The four candidate Lyapunov functions are as follows: 。 7. The aircraft output feedback attitude control method of claim 1, wherein, The filtering error of the angular velocity observation value is defined as follows: The output feedback attitude control law based on the angular velocity observer comprises the following steps: The proportional-differential tracking controller is designed as follows: ； wherein , is a normal number; is an aircraft angular velocity; is a skew-symmetric matrix corresponding to the aircraft angular velocity; is a control torque; is a moment of inertia; is a modified Rodrigues parameter; The angular velocity observation value of the angular velocity observer Replace the aircraft angular velocity in the proportional-derivative tracking controller The value of is used to obtain the output attitude control law based on the angular velocity observer: ； wherein is the angular velocity observation.