Aircraft multi-mode steady-state control method based on dynamic arm stretching

Abstract

The invention discloses an aircraft multi-modal steady-state control method based on dynamic arm stretching, which overcomes the multi-modal control problem of a deformable aircraft through dynamic wheelbase adjustment and control parameter collaborative optimization, and specifically comprises the following steps: establishing a real-time mapping relation of arm length-control parameter-distribution matrix; designing an inertial parameter adaptive PID (Proportion Integration Differentiation) correction algorithm, and constructing a dynamic control distribution matrix; the method is suitable for rotor aircrafts and hybrid layout aircrafts, and is especially suitable for flight control in scenes such as urban airspace and narrow take-off and landing sites; the flight control system can obtain the external environment condition in real time according to a sensor and an identification technology, so that the flight stability and safety are improved; by dynamically adjusting the length of the arms, the aircraft can adapt to various complex task requirements; and in combination with the control parameter updating equation, the flight control system can adjust the control parameters and control the distribution matrix in real time, so that the aircraft has higher autonomous control capability and adaptability.

Description

Technical Field

[0001] The present invention belongs to the technical field of aircraft control, and particularly relates to a multi-modal steady-state control method for an aircraft based on dynamic arm telescoping. Background Art

[0002] In the existing aircraft control technology, control parameters are usually designed based on static models and it is difficult to meet the requirements of complex tasks (such as narrow flight channels, payload changes). Although some studies have achieved adjustable wheelbases through telescoping arms (for example, Patent CN117902079A proposes a drone arm with a variable wheelbase), it only focuses on mechanical structure adjustment and does not deeply integrate the dynamic adjustment of the arm with the flight control system, resulting in the following problems: insufficient stability; static control parameters cannot adapt to the change of dynamic characteristics caused by the change of the arm in real time, resulting in attitude instability and low control efficiency in complex environments. Summary of the Invention

[0003] The purpose of the present invention is to solve the defects existing in the prior art and propose a multi-modal steady-state control method for an aircraft based on dynamic arm telescoping. By means of dynamic wheelbase adjustment and collaborative optimization of control parameters, the multi-modal control problem of deformable aircraft is overcome. Specifically, it includes: establishing a real-time mapping relationship among arm length - control parameters - distribution matrix, designing a PID correction algorithm with adaptive inertial parameters, and constructing a dynamic control distribution matrix.

[0004] To achieve the purpose of the present invention, the present invention discloses a multi-modal steady-state control method for an aircraft based on dynamic arm telescoping, including the following steps:

[0005] Step 1: Determine the arm change requirement;

[0006] Step 2: Perform high-precision servo control according to the arm change;

[0007] Step 3: Correct the adaptive PID parameters;

[0008] Step 4: Optimize the control distribution matrix.

[0009] Further, in Step 1, the aircraft is equipped with a telescoping arm control system, which can adjust the arm length according to real-time flight requirements during flight; the control system realizes the telescoping change of the wheelbase through an electric or hydraulic drive mechanism; the flight control system obtains real-time flight task requirements and surrounding environment data (such as narrowing flight channels, strong airflows, vertical takeoff and landing tasks, etc.) in real time, and dynamically calculates the amplitude and direction of arm adjustment according to the data change to optimize the maneuverability and environmental adaptability of the aircraft in real time;

[0010] The telescoping arm adopts a carbon fiber - titanium alloy composite structure, and the drive module integrates an electric servo motor (accuracy ±1mm) and a redundant encoder, supporting the wheelbase within ~ Continuously adjustable within a range;

[0011] Based on the mission mode (takeoff / landing / cruise / maneuver) and environmental data (such as lidar point cloud, air pressure gradient), the flight control system calculates the optimal telescopic length through the following formula:

[0012]

[0013] is the load compensation coefficient; is the aerodynamic coupling coefficient; is the external load; is the maximum rotor speed.

[0014] Furthermore, step 1 is specifically to define the relationship between the standard wheelbase L and the target wheelbase L_target according to the mission requirements:

[0015]

[0016] where ΔL is the wheelbase change amount, which is determined by looking up the table according to the preset mission mode:

[0017]

[0018] In the formula, is the load compensation coefficient; is the aerodynamic coupling coefficient; is the external load; is the maximum rotor speed.

[0019] Furthermore, in step 2, a servo motor drive model is established:

[0020]

[0021] Among them, is the motor gain, is the friction compensation term; the control law adopts feedforward + feedback composite control:

[0022]

[0023] Among them, is the control input, is the actual arm length; is the target arm length.

[0024] Furthermore, in step 3, a wheelbase influence factor is introduced:

[0025]

[0026] is the maximum wheelbase adjustment speed; is the actual arm length; is the target arm length; is the maximum adjustment speed; The PID gain update formula is:

[0027]

[0028] In the formula, , is the moment of inertia of the actual response rotating shaft, and γ_x is the gain coefficient, which adjusts the sensitivity of the differential gain under dynamic conditions, considering the rotor gyro effect and the airflow disturbance response; , ; (real-time arm length); is the step function, which activates the integral term when the yaw error exceeds 2°; is used to smooth the sign function to avoid switching jitter.

[0029] Furthermore, in step 4,

[0030]

[0031] Among them, is a three-dimensional vector, corresponding to the roll, pitch, and yaw moments respectively; is the thrust coefficient, the thrust generated by unit rotational speed squared, ; is the power coefficient, the thrust generated by unit rotational speed squared, ; is the th motor speed ( ).

[0032] Compared with the prior art, the remarkable progress of the present invention lies in: 1) improving environmental adaptability: The flight control system can obtain the external environmental conditions (such as strong wind, turbulence, etc.) in real time according to sensors and identification technologies, and dynamically adjust the arm length for different flight environments to improve flight stability and safety, and dynamically adjust the mobility and stability to adapt to various flight environments; 2) improving task efficiency: By dynamically adjusting the arm length, the aircraft can adapt to various complex task requirements. According to the flight task requirements, the aircraft can realize the task requirements of the aircraft size, flight mobility and stability in tasks such as high-speed maneuvering, obstacle avoidance, and complex flight channels by adjusting the wheelbase in real time; it can shorten the wheelbase and reduce the size during the takeoff and landing phases, reducing the area requirement for the takeoff and landing sites; 3) enhancing the autonomous control ability of the aircraft: Combining the control parameter update equation, the flight control system can adjust the control parameters and the control distribution matrix in real time, enabling the aircraft to have higher autonomous control ability and adaptability.

[0033] To more clearly illustrate the functional characteristics and structural parameters of the present invention, the following further explains in conjunction with the accompanying drawings and specific embodiments. Description of the Drawings

[0034] The drawings described herein are used to provide a further understanding of the present invention, and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention, and do not constitute an improper limitation of the present invention. In the drawings:

[0035] Figure 1 is a flowchart of a multi-modal steady-state control method for an aircraft based on dynamic arm extension and retraction;

[0036] Figure 2 is a schematic diagram of the aircraft control system architecture;

[0037] Figure 3 is a schematic diagram of the operation of the arm servo system;

[0038] Figure 4 is a flowchart of parameter tuning;

[0039] Figure 5 is a diagram of the implementation of the control allocation matrix solution. Specific Embodiments

[0040] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments; based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0041] A multi-modal steady-state control method for an aircraft based on dynamic arm extension and retraction adjustment. By adjusting the aircraft wheelbase in real time and optimizing the control parameters and control allocation matrix, the flight stability problem during the deformation process is solved. The present invention is applicable to rotary-wing aircraft and hybrid layout aircraft, and is particularly suitable for flight control in scenarios such as urban airspace and narrow takeoff and landing sites. The specific embodiments are as follows:

[0042] Step 1: Determine the arm change requirements;

[0043] Step 2: Perform high-precision servo control according to the arm change;

[0044] Step 3: Correct the adaptive PID parameters;

[0045] Step 4: Optimize the control allocation matrix.

[0046] Specifically, in one embodiment, in step 1, the aircraft is equipped with a telescopic arm control system that can adjust the arm length according to real-time flight requirements during flight; the control system realizes the telescopic change of the wheelbase through an electric or hydraulic drive mechanism; the flight control system obtains real-time flight task requirements and surrounding environment data (such as narrowing flight channels, strong airflows, vertical takeoff and landing tasks, etc.), and dynamically calculates the amplitude and direction of the arm adjustment according to the data changes to optimize the aircraft's maneuverability and environmental adaptability in real time;

[0047] The telescopic arm adopts a carbon fiber-titanium alloy composite structure, and the drive module integrates an electric servo motor (accuracy ±1mm) and a redundant encoder, supporting the wheelbase to be continuously adjusted within the range of ~ ;

[0048] Based on the mission mode (takeoff / landing / cruise / maneuver) and environmental data (such as lidar point cloud, pressure gradient), the flight control system calculates the optimal telescopic length through the following formula:

[0049]

[0050] is the load compensation coefficient; is the aerodynamic coupling coefficient; is the external load; is the maximum rotor speed.

[0051] Specifically, in one embodiment, step 1 is specifically defined as the relationship between the standard wheelbase L and the target wheelbase L_target according to the mission requirements:

[0052]

[0053] where ΔL is the wheelbase change amount, which is determined by looking up the table through the preset mission mode:

[0054]

[0055] In the formula, is the load compensation coefficient; is the aerodynamic coupling coefficient; is the external load; is the maximum rotor speed.

[0056] Specifically, in one embodiment, in step 2, a servo motor drive model is established:

[0057]

[0058] where, is the motor gain, is the friction compensation term; the control law adopts feedforward + feedback composite control:

[0059]

[0060] Among them, is the control input, is the actual arm length; is the target arm length.

[0061] Specifically, in one embodiment, in step 3, an axle distance influence factor is introduced:

[0062]

[0063] is the maximum speed of axle distance adjustment; is the actual arm length; is the target arm length; is the maximum adjustment speed; The PID gain update formula is:

[0064]

[0065] In the formula, , is the moment of inertia of the actual response rotating shaft, γ_x is the gain coefficient, which adjusts the sensitivity of the differential gain under dynamic conditions, considering the rotor gyroscopic effect and the response of air flow disturbance; , ; (real-time arm length); is the step function, which activates the integral term when the yaw error exceeds 2°; is used to smooth the sign function to avoid switching jitter.

[0066] Specifically, in one embodiment, in step 4,

[0067]

[0068] Among them, is a three-dimensional vector, corresponding to the roll, pitch, and yaw torques respectively; is the thrust coefficient, the thrust generated by unit rotational speed squared, ; is the power coefficient, the thrust generated by unit rotational speed squared, ; is the th motor speed ( ).

[0069] Such as Figure 1As shown, the figure demonstrates the structure and working process of the aircraft's dynamic arm adjustment system. The aircraft control system sends control signals to the telescopic arm control system, instructing the aircraft to adjust the arm length according to mission requirements. The telescopic arm control system precisely adjusts the wheelbase through an electric servo motor and a redundant encoder. The wheelbase adjustment module uses carbon fiber-titanium alloy composite materials to ensure stability in high-intensity environments. Meanwhile, the flight control system receives environmental data (such as load changes, strong wind environment) and flight mission requirements in real-time, calculates the amplitude and direction of arm adjustment, and ensures that the aircraft adapts to the flight requirements of different environments.

[0070] As Figure 2 shown, the figure shows the main module composition of the aircraft control system, including a mission parsing module, an arm servo mechanism, a parameter adaptation module, and a control allocator. The mission parsing module is responsible for receiving flight mission information and defining the arm length requirements according to different mission modes (takeoff and landing, cruise, maneuver). The arm servo mechanism: realizes the telescoping of the arm through electric or hydraulic drive to adjust the wheelbase of the aircraft. The parameter adaptation module calculates the inertial parameters of the aircraft in the current state in real-time and adjusts the gains of the PID controller through an identification algorithm. The control allocator dynamically adjusts the control allocation matrix according to the real-time arm length and aircraft state to optimize the control performance of the aircraft.

[0071] As Figure 3 shown, the figure demonstrates how the arm servo system drives the telescoping of the arm through an electric servo motor to ensure the dynamic adjustment of the aircraft's wheelbase. The servo motor drive shows the process of the servo motor driving the arm to telescope, and the motor adjusts the arm length according to the signal sent by the flight control system. Friction compensation adds a friction compensation model to optimize the control accuracy of the servo system and avoid errors caused by friction.

[0072] As Figure 4 shown, the parameter adaptive update process of this system uses a three-level linkage mechanism to achieve dynamic tuning: the master controller queries the mechanism dynamics parameters from the inertia database, returns the moment of inertia in real-time based on the pre-stored model, and then inputs the arm length, air density, yaw angular velocity, and acceleration into the regulator. The output is an iteratively processed PID parameter group for the main controller's control input.

[0073] As Figure 5 shown, the control allocation matrix solution uses a hierarchical architecture: first, construct the allocation matrix, find the pseudo-inverse matrix through truncated SVD decomposition, then optimize the thrust allocation with constrained quadratic programming, and finally achieve motor manipulation.

[0074] It should be noted that, in this document, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variation thereof is intended to cover non-exclusive inclusion, such that a process, method, article or apparatus comprising a series of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article or apparatus.

[0075] Although the embodiments of the present invention have been shown and described, it will be understood by those of ordinary skill in the art that various changes, modifications, substitutions and variations can be made to these embodiments without departing from the principles and spirit of the present invention, and the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A multi-modal steady-state control method for an aircraft based on dynamic arm extension and retraction, characterized in that: The following steps are involved: Step 1: Determine the need for arm changes; the flight control system obtains the external environment in real time based on sensors and identification technology, and dynamically adjusts the arm length according to different flight environments; Step 2: Perform high-precision servo control according to the changes of the machine arm; Step 3: Correct the adaptive PID parameters; Step 4: Optimize the control allocation matrix.

2. The method for multi-modal steady-state control of an aircraft based on dynamic arm extension and retraction according to claim 1, characterized in that: In step 1, the aircraft is equipped with a telescopic arm control system, which can adjust the arm length according to real-time flight requirements during flight; the control system realizes the telescopic change of the wheelbase through an electric or hydraulic drive mechanism; the flight control system obtains flight mission requirements and surrounding environment data in real time, and dynamically calculates the amplitude and direction of the arm adjustment according to the data changes, so as to optimize the aircraft's maneuverability and environmental adaptability in real time; the telescopic arm adopts a carbon fiber-titanium alloy composite structure, and the drive module integrates an electric servo motor and a redundant encoder, which supports the wheelbase in ~ Continuous adjustment within the range; The flight control system calculates the optimal telescopic length based on the mission mode and environmental data using the following formula: is the load compensation coefficient; is the aerodynamic coupling coefficient; is the external load; is the maximum rotor speed.

3. The method for multi-modal steady-state control of an aircraft based on dynamic arm extension and retraction according to claim 2, characterized in that: Step 1 specifically defines the relationship between the standard wheelbase L and the target wheelbase L_target according to the task requirements: Where ΔL is the wheelbase change, which is determined by looking up the table in the preset mission mode: In the formula, is the load compensation coefficient; is the aerodynamic coupling coefficient; is the external load; is the maximum rotor speed.

4. The method for multi-modal steady-state control of an aircraft based on dynamic arm extension and retraction according to claim 1, characterized in that: In step 2, build the servo motor drive model: in, is the motor gain, is the friction compensation term; the control law adopts feedforward + feedback composite control: in, is the control input, is the actual arm length; is the target arm length.

5. The method for multi-modal steady-state control of an aircraft based on dynamic arm extension and retraction according to claim 1, characterized in that: In step 3, the wheelbase influencing factor is introduced: Adjust the maximum speed for the wheelbase; is the actual arm length; is the target arm length; is the maximum regulating speed; the PID gain update formula is: In the formula, , is the actual moment of inertia of the response shaft, γ_x is the gain coefficient, which adjusts the sensitivity of the differential gain under dynamic conditions, taking into account the rotor gyro effect and airflow disturbance response; , ; ; It is a step function, and the integral term is activated when the yaw error exceeds 2°; Used to smooth the sign function and avoid switching jitter.

6. The method for multi-modal steady-state control of an aircraft based on dynamic arm extension and retraction according to claim 1, characterized in that: In step 4, in, are three-dimensional vectors, corresponding to rolling, pitching, and yaw moments; is the pull coefficient, the thrust generated by the square of the unit speed, ; is the power coefficient, the thrust generated per unit speed squared, ; For the The speed of the motor ( ).

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