A controllability analysis method for deformable UAV
By constructing a longitudinal dynamic model of the aircraft containing deformation characteristics and a controllability matrix based on the constraint extension method, the controllability analysis problem of deformable drones in multi-deformed and full-flight states is solved, and the accuracy analysis of the controllability of the drone and the adaptability improvement of complex dynamic responses is achieved.
Patent Information
- Application Number
- CN202510185568.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2025-02-20
- Publication Date
- 2025-05-13
- Estimated Expiration
- 2045-02-20
AI Technical Summary
The existing drone controllability analysis methods are difficult to effectively analyze the controllability of deformable drones in multi-deformed states and full-flight states, especially in complex nonlinear dynamic characteristics and large deformation conditions.
By determining the geometric parameters and aerodynamic parameters of the deformable drone, a longitudinal dynamic model of the aircraft containing deformation characteristics is constructed, and the controllability matrix is constructed based on the constraint extension method to conduct controllability analysis of the deformable drone in multiple deformation states and different flight states.
The controllability of the deformable drone is realized, and the controllability of the multi-deformable state and flight state of the deformable drone can be fully described, and the controllability changes of the drone during the entire flight process can be improved to improve the adaptability to complex nonlinear dynamic responses.
Smart Images
Figure CN119670505B_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of flight mechanics and control, and in particular to a controllability analysis method for a deformable unmanned aerial vehicle. Background Art
[0002] Controllability analysis of deformable UAVs in multiple deformation states and full flight states is a complex interdisciplinary problem. Deformable UAVs achieve performance optimization in different flight states by dynamically adjusting their shape or structure. Compared with traditional fixed-wing UAVs, they have advantages such as optimized aerodynamic efficiency, wider flight envelope, higher mission flexibility, stronger environmental adaptability and higher battlefield survivability. However, due to its own deformable characteristics, it brings great challenges to the controllability analysis of multiple deformation states and flight states within the full envelope, which are mainly reflected in the following points:
[0003] 1. For different flight states and different flight missions, the deformable UAV undergoes different degrees of deformation, and the geometric parameters and aerodynamic parameters of the aircraft are different;
[0004] 2. During a flight mission, the aircraft may be deformed significantly to adapt to complex mission requirements, and the flight state and aerodynamic parameters of the aircraft may change significantly, rapidly and continuously;
[0005] 3. The uncertainty of geometric parameters and aerodynamic parameters of deformable UAVs caused by deformation errors seriously interferes with the calculation of static balance points and controllability analysis;
[0006] At present, there is a lack of research on controllability analysis methods for deformable UAVs. Existing controllability analysis methods for the flight state within the full flight envelope of UAVs are mainly aimed at traditional fixed-wing aircraft, and static analysis is performed based on discrete flight states (such as take-off, cruising, dive, etc.), ignoring the continuity of the dynamic deformation process and not involving the changes in geometric parameters and aerodynamic parameters caused by aircraft deformation; the flight control of deformable UAVs needs to consider aerodynamic characteristics, dynamics and structural coupling at the same time, but traditional methods are mostly aimed at a single subsystem and lack systematicity; traditional control design is based on linearized models, which is difficult to adapt to the complex nonlinear dynamic characteristics of deformable UAVs in flight, especially the controllability of the deformation process; and the controllability analysis of flexible aircraft mainly studies small-scale elastic deformation and cannot cope with mission situations with large changes in complex morphology; the controllability analysis of distributed propulsion type aircraft is mostly limited to specific flight modes and switching, and lacks adaptability to dynamic control of continuously changing morphology.
[0007] Therefore, there is an urgent need to provide a controllability analysis method for a deformable UAV so as to accurately analyze the controllability of the multiple deformation states and flight states of the deformable UAV. Summary of the invention
[0008] The purpose of this application is to provide a controllability analysis method for a deformable UAV, which can accurately analyze the controllability of the multiple deformation states and flight states of the deformable UAV.
[0009] To achieve the above objectives, this application provides the following solutions:
[0010] The present application provides a method for analyzing the controllability of a deformable UAV, and the method for analyzing the controllability of a deformable UAV includes:
[0011] Determine the deformation characteristic quantity according to the geometric parameters of the deformable UAV; the geometric parameters include: the wingspan, reference wing area, average aerodynamic chord length, moment of inertia and center of gravity position of the deformable UAV;
[0012] According to the deformation characteristic quantity, geometric parameters and aerodynamic parameters, based on the longitudinal dynamic equation, an aircraft longitudinal dynamic model including deformation characteristics is constructed; the aerodynamic parameters include: lift coefficient, drag coefficient and moment coefficient;
[0013] According to the aircraft longitudinal dynamics model including deformation characteristics, the static equilibrium point of the deformable UAV in multiple deformation states and different flight states is determined;
[0014] According to the static equilibrium points of the deformable UAV in multiple deformation states and different flight states, the controllability matrix is constructed based on the constraint continuation method.
[0015] The controllability of the deformable UAV in multiple deformation states and different flight states is analyzed based on the controllability matrix.
[0016] Optionally, determining the deformation feature quantity according to the geometric parameters of the deformable UAV specifically includes:
[0017] Using the formula Determining deformation characteristic quantities;
[0018] in, is the deformation feature, are the current geometric parameters of the deformable drone, is the maximum value of the geometric parameters of the deformable UAV during the deformation process, is the minimum value of the geometric parameters of the deformable UAV during the deformation process.
[0019] Optionally, the step of constructing an aircraft longitudinal dynamics model including deformation characteristics based on the longitudinal dynamics equation according to the deformation characteristic quantity, geometric parameters and aerodynamic parameters specifically includes:
[0020] use Determine the aircraft longitudinal dynamics model including deformation characteristics;
[0021] in, is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , m is the mass of the deformable drone, g is the acceleration of gravity, D is the resistance, is the resistance error, is the drag coefficient error, ρ is the air density, S is the actual reference area, ... are fitting parameters based on data. is the deformation feature, ... are fitting parameters based on data. is the angle of attack of the drone, is the flight speed, is the aerodynamic torque error, is the engine thrust, is the height change rate, is the track angle, is the rate of change of track angle, is the intermediate variable, , is the rate of change of angle of attack, is the intermediate variable, , is the pitch angular velocity, is the pitch angular acceleration, is the elevator deflection size, is the velocity change rate, b is the average aerodynamic chord length, is the y-axis inertia.
[0022] Alternatively, using the formula Determine aerodynamic moment error;
[0023] in, is the actual reference area error, is the torque coefficient, is the torque coefficient error, is the average aerodynamic chord length change, is the change of center position, is the actual resistance, is the actual lift.
[0024] Alternatively, using the formula Determine the resistance error.
[0025] Optionally, determining the static equilibrium point of the deformable UAV in multiple deformation states and different flight states according to the aircraft longitudinal dynamics model including the deformation characteristics specifically includes:
[0026] The static conditions or numerical solution methods are adopted for the longitudinal dynamics model of the aircraft containing deformation characteristics to determine the static equilibrium point of the deformable UAV in multiple deformation states and different flight states.
[0027] Optionally, the numerical solution method includes: Newton iteration method.
[0028] Optionally, constructing a controllability matrix based on the constraint continuation method according to the static balance points of the deformable UAV in multiple deformation states and different flight states specifically includes:
[0029] Based on the constraint continuation method, the static equilibrium points of the deformable UAV in multiple deformation states and different flight states are connected in series using a continuous calculation method.
[0030] According to the static equilibrium points after series connection, the controllability matrix is constructed.
[0031] According to the specific embodiments provided in this application, this application has the following technical effects:
[0032] The present application provides a method for analyzing the controllability of a deformable UAV. According to the deformation characteristic quantity, geometric parameters and aerodynamic parameters, based on the longitudinal dynamics equation, an aircraft longitudinal dynamics model including deformation characteristics is constructed; that is, the deformation characteristic quantity is embedded in the longitudinal dynamics equation, a complete nonlinear mathematical model of a deformable UAV is established, and the dynamic behavior of the UAV in different flight states and deformation states is accurately described; based on the constraint continuation method, the static equilibrium points of the deformable UAV in different deformation states and different flight states such as level flight, climbing and descent are continuously calculated, and the controllability matrix of different static equilibrium points is calculated, so as to analyze the controllability of the deformable UAV in multiple deformation states and full flight states; by calculating the controllability matrix of different static equilibrium points, the coupling problem between aerodynamic characteristics, dynamics and structural deformation is comprehensively considered. The present application can realize the transition analysis from static state to dynamic process, and comprehensively describe the controllability changes of the deformable UAV in the whole flight process; then obtain the key control characteristics in all deformation states, and improve the adaptability to complex nonlinear dynamic response; further, it can realize the accurate analysis of the controllability of the deformable UAV in multiple deformation states and flight states. BRIEF DESCRIPTION OF THE DRAWINGS
[0033] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0034] Figure 1 This is a flow chart of a controllability analysis method for a deformable UAV in one embodiment of the present application;
[0035] Figure 2 This is a schematic diagram of the overall process of a controllability analysis method for a deformable UAV in one embodiment of the present application. DETAILED DESCRIPTION
[0036] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.
[0037] In order to make the above-mentioned objects, features and advantages of the present application more obvious and easy to understand, the present application is further described in detail below with reference to the accompanying drawings and specific implementation methods.
[0038] In an exemplary embodiment, Figure 1 and Figure 2 As shown, a method for analyzing the controllability of a deformable UAV is provided, and the method includes the following S101 to S105. Among them:
[0039] S101, determining deformation feature quantities according to geometric parameters of the deformable UAV; the geometric parameters include: wingspan, reference wing area, average aerodynamic chord length, moment of inertia and center of gravity position of the deformable UAV;
[0040] Among them, taking the variable wingtip UAV as an example, the formula is used Determine the deformation feature quantity; at this time, Indicates the current geometric parameters of the deformable drone, which can be the wing area or the wing span; is the maximum value of the geometric parameters of the deformable UAV during the deformation process, is the minimum value of the geometric parameters of the deformable UAV during the deformation process; A and A max They are respectively the parameter value under a certain deformation degree and the maximum value of the parameter, such as the reference area corresponding to the current deformation and the maximum reference area.
[0041] S102, constructing an aircraft longitudinal dynamics model including deformation characteristics based on the longitudinal dynamics equation according to the deformation characteristic quantity, geometric parameters and aerodynamic parameters; the aerodynamic parameters include: lift coefficient, drag coefficient and moment coefficient;
[0042] After determining the deformation characteristic, the corresponding actual reference area S and wing span for:
[0043] ;
[0044] ;
[0045] in, is the actual maximum reference area, is the minimum actual reference area. is the maximum wing span, is the minimum wing span;
[0046] After considering the deformation characteristics, the aerodynamic parameters are fitted using the following nonlinear polynomial function:
[0047] ;
[0048] in, The lift coefficient in the longitudinal aerodynamic parameters of the deformable UAV is represented by: The drag coefficient in the longitudinal aerodynamic parameters of the deformable UAV is represented by: Represents the moment coefficient in the longitudinal aerodynamic parameters of the deformable UAV, is the angle of attack of the drone, is the deformation characteristic quantity, that is, the deformation rate, is the flight speed, is the deflection of the elevator, the coefficient - , - , - All of them are fitting parameters based on data. The aerodynamic parameters are obtained from experiments, and the angle of attack, deformation rate, flight speed and elevator deflection of the UAV are obtained from the sensor feedback in the experiment.
[0049] In order to further improve the accuracy of the representation, the deformation characteristic quantity error, geometric parameter error and aerodynamic parameter error are considered; the actual geometric parameters and actual aerodynamic parameters are obtained, and the relationship between the actual quantity and the ideal quantity is obtained. , , , , , the actual reference area error and aerodynamic parameter error considering the deformation error are obtained:
[0050] ;
[0051] According to the relationship between lift L, drag D and aerodynamic moment M and the corresponding aerodynamic coefficient , , , and then get the errors of lift L, drag D and aerodynamic moment M:
[0052] ;
[0053] The longitudinal dynamics equation of a traditional fixed-wing aircraft is:
[0054] ;
[0055] The above-mentioned geometric parameters and aerodynamic parameters affected by deformation characteristics are further embedded to obtain the aircraft longitudinal dynamics model including deformation characteristics:
[0056] ;
[0057] in, is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , m is the mass of the deformable drone, g is the acceleration of gravity, D is the resistance, is the resistance error, is the drag coefficient error, ρ is the air density, S is the actual reference area, ... are fitting parameters based on data. is the deformation feature, ... are fitting parameters based on data. is the angle of attack of the drone, is the flight speed, is the aerodynamic torque error, is the engine thrust, is the height change rate, is the track angle, is the rate of change of track angle, is the intermediate variable, , is the rate of change of angle of attack, is the intermediate variable, , is the pitch angular velocity, is the pitch angular acceleration, is the elevator deflection size, is the velocity change rate, b is the average aerodynamic chord length, is the y-axis inertia.
[0058] S103, determining the static equilibrium point of the deformable UAV in multiple deformation states and different flight states according to the aircraft longitudinal dynamics model including the deformation characteristics;
[0059] In S103, according to the longitudinal dynamics model of the aircraft including deformation characteristics, the coordinate system and symbol convention are established, the force and moment balance equations under different states are listed, and the constraints under different flight states are considered (such as the sideslip angle in level flight state). , lateral force , yaw moment ) Calculate the static equilibrium point under different deformation states and flight states, including the force and torque balance conditions under level flight, climb, dive, hover, etc. The flight state is divided into several working conditions (such as low-speed flight, high-speed cruise, stall, etc.) according to speed, altitude, special attitude state and flight mission to provide a basis for subsequent analysis. For the aircraft longitudinal dynamics model containing deformation characteristics, static conditions are taken, that is, all time derivatives are zero, and the equilibrium point is solved. Numerical solution methods (such as Newton iteration method) can also be used to define a nonlinear equation group, give an initial guess value, calculate the Jacobian matrix, use Newton iteration method to update the solution vector, perform iterative calculations and check convergence at the same time to calculate the static equilibrium point and obtain specific conditions for different flight states.
[0060] S104, constructing a controllability matrix based on the constraint continuation method according to the static equilibrium points of the deformable UAV in multiple deformation states and different flight states;
[0061] The process of using the constrained continuation method is:
[0062] Introduce additional variables for each constraint, such as Lagrange multipliers or penalty factors; construct an extension function to combine the original objective function and the constraints. The function usually includes a penalty term to "punish" violations of the constraints during the iteration process; use unconstrained optimization methods or simple constrained optimization methods to solve the extension problem. During the iteration process, the weight of the penalty term will gradually increase, so that the solution gradually approaches the feasible domain of the original problem; update the candidate solution of the original problem based on the solution of the extension problem, and repeat the iterative process until the stopping criterion is met. Through the above steps and continuous calculation methods, the equilibrium points of different flight states are connected in series to ensure the continuity of state changes during the deformation process;
[0063] The constrained continuation algorithm is implemented in MATLAB. Starting from a known equilibrium point, other equilibrium points are continuously calculated by gradually adjusting flight parameters (such as speed, angle of attack, and wingspan) to ensure that the calculation process does not jump and smoothly covers the entire flight envelope. The key technology is to introduce constraints to ensure the continuity of the solution path.
[0064] The process of constructing the controllability matrix is:
[0065] First, local linearization is performed. Near each static equilibrium point, the nonlinear dynamic equations are linearized based on Taylor expansion:
[0066] ;
[0067] Among them, A is the system matrix, B is the input matrix, , is the initial state quantity and control quantity, is the change of system state quantity, is the system state quantity, is the system control quantity, f is the system equation;
[0068] Use numerical methods (such as the finite difference method) to calculate the system matrix A and the input matrix B and construct the controllability matrix ;
[0069] S105, performing controllability analysis of the deformable UAV in multiple deformation states and different flight states according to the controllability matrix.
[0070] By calculating the controllability matrix C, check whether the rank of the controllability matrix is equal to the state dimension n of the system, and judge the complete controllability of the system. Compare the changes in the controllability matrix under different deformation parameters (such as changes in wing span), and draw the relationship curve between parameters and controllability. In this way, the controllability of the multi-deformation state and flight state of the deformable UAV can be judged. If the rank of the obtained controllability matrix is equal to the dimension of the state vector, the system is completely controllable. The system is transferred from any initial state to any final state by inputting the control amount u(t). If the rank of the controllability matrix is less than the dimension of the state vector, the system is not completely controllable, that is, there are some states that cannot be reached by inputting the control amount, and the dynamic behavior of the system is restricted.
[0071] In this application, all actions to obtain signals, information or data are carried out in compliance with the relevant data protection laws and policies of the country where they are located and with the authorization given by the owner of the corresponding device.
[0072] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, 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.
[0073] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.
Claims
1. A controllability analysis method for a deformable UAV, characterized in that: The controllability analysis method of the deformable UAV comprises: Determine the deformation characteristic quantity according to the geometric parameters of the deformable UAV; the geometric parameters include: the wingspan, reference wing area, average aerodynamic chord length, moment of inertia and center of gravity position of the deformable UAV; According to the deformation characteristic quantity, geometric parameters and aerodynamic parameters, based on the longitudinal dynamic equation, an aircraft longitudinal dynamic model including deformation characteristics is constructed; the aerodynamic parameters include: lift coefficient, drag coefficient and moment coefficient; According to the aircraft longitudinal dynamics model including deformation characteristics, the static equilibrium point of the deformable UAV in multiple deformation states and different flight states is determined; According to the static equilibrium points of the deformable UAV in multiple deformation states and different flight states, the controllability matrix is constructed based on the constraint continuation method. According to the controllability matrix, the controllability analysis of the deformable UAV in multiple deformation states and different flight states is carried out; The aircraft longitudinal dynamics model including deformation characteristics is constructed based on the longitudinal dynamics equation according to the deformation characteristic quantity, geometric parameters and aerodynamic parameters, specifically including: use Determine the aircraft longitudinal dynamics model including deformation characteristics; in, is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , is the intermediate variable, , m is the mass of the deformable drone, g is the acceleration of gravity, D is the resistance, is the resistance error, is the drag coefficient error, ρ is the air density, S is the actual reference area, ... are fitting parameters based on data. is the deformation feature, ... are fitting parameters based on data. is the angle of attack of the drone, is the flight speed, is the aerodynamic torque error, is the engine thrust, is the height change rate, is the track angle, is the rate of change of track angle, is the intermediate variable, , is the rate of change of angle of attack, is the intermediate variable, , is the pitch angular velocity, is the pitch angular acceleration, is the elevator deflection size, is the velocity change rate, b is the average aerodynamic chord length, is the y-axis inertia.
2. The controllability analysis method of a deformable UAV according to claim 1, characterized in that: Determining the deformation feature quantity according to the geometric parameters of the deformable UAV specifically includes: Using the formula Determining deformation characteristic quantities; in, is the deformation feature, are the current geometric parameters of the deformable drone, is the maximum value of the geometric parameters of the deformable UAV during the deformation process, is the minimum value of the geometric parameters of the deformable UAV during the deformation process.
3. The controllability analysis method of a deformable UAV according to claim 1, characterized in that: Using the formula Determine aerodynamic moment error; in, is the actual reference area error, is the torque coefficient, is the torque coefficient error, is the average aerodynamic chord length change, is the change of center position, is the actual resistance, is the actual lift.
4. The controllability analysis method of a deformable UAV according to claim 3 is characterized in that: Using the formula Determine the resistance error; where C D is the resistance coefficient.
5. The controllability analysis method of a deformable UAV according to claim 1, characterized in that: The method of determining the static equilibrium point of the deformable UAV in multiple deformation states and different flight states based on the aircraft longitudinal dynamics model including the deformation characteristics specifically includes: The static conditions or numerical solution methods are adopted for the longitudinal dynamics model of the aircraft containing deformation characteristics to determine the static equilibrium point of the deformable UAV in multiple deformation states and different flight states.
6. The controllability analysis method of a deformable UAV according to claim 5, characterized in that: The numerical solution method includes: Newton iteration method.
7. The controllability analysis method of a deformable UAV according to claim 1, characterized in that: The controllability matrix is constructed based on the constraint continuation method according to the static balance points of the deformable UAV in multiple deformation states and different flight states, specifically including: Based on the constraint continuation method, the static equilibrium points of the deformable UAV in multiple deformation states and different flight states are connected in series using a continuous calculation method. According to the static equilibrium points after series connection, the controllability matrix is constructed.