A tilt-rotor omnidirectional unmanned aerial vehicle control method and related device

Abstract

This invention relates to the field of unmanned aerial vehicle (UAV) control technology, specifically to a tilting rotor omnidirectional UAV control method and related equipment. By acquiring the UAV's current pose information (including position, attitude, and body angular velocity) and desired pose information, the position controller generates a desired total force based on the position deviation, the attitude controller generates a desired angular velocity based on the attitude difference, and the angular velocity controller generates a desired total torque based on the angular velocity deviation, forming a three-level control closed loop. The control distributor uses a rotor configuration dynamics model to convert the total force and torque into desired thrust for each rotor, calculates the desired rotational speed based on the thrust-rotor speed correspondence, and controls the rotor rotation. This scheme achieves decoupling optimization of position and attitude control, improving pose control accuracy and response speed.

Description

Technical Field

[0001] This invention relates to the field of unmanned aerial vehicle (UAV) control technology, specifically to a tilting rotor omnidirectional UAV control method and related equipment. Background Technology

[0002] An omnidirectional UAV is a UAV that achieves omnidirectionality through special rotor configurations such as fixed rotor tilt angle, variable rotor tilt angle, or heterogeneous rotors. The components of the thrust generated by each rotor of an omnidirectional UAV, after being decomposed, are parallel to the three orthogonal axes of the coordinate system in three-dimensional space, giving the system full-drive or over-drive characteristics and enabling the UAV to move in all directions.

[0003] The control methods for omnidirectional UAVs differ from those for traditional multi-rotor UAVs. Due to the unique rotor arrangement, control allocation cannot rely on a simple weighted sum of the thrust generated by each rotor. For omnidirectional UAV systems, closed-loop control algorithms such as PID controllers need to be incorporated into the designed flight control structure for closed-loop flight control. While many open-source flight controllers for traditional multi-rotor UAVs, such as PX4 and Ardupilot, exist, they are not well-suited for omnidirectional UAV flight control. Therefore, it is necessary to design specific control methods for omnidirectional UAVs with particular configurations. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a tilting rotor omnidirectional UAV control method and related equipment to address the shortcomings of the prior art, and to solve the technical problem of improper handling of coupling effects in the connection of position control, attitude control and angular velocity control in the prior art.

[0005] The objective of this invention is achieved through the following technical solutions: In a first aspect, the present invention provides a method for controlling an omnidirectional unmanned aerial vehicle with a tilting rotor, comprising: Obtain the current pose information of the drone, which includes the current position, current attitude, and current angular velocity of the drone. Obtain desired pose information, which includes desired position and orientation information; Based on the desired position and the current position, the desired total force is generated by the position controller; Based on the desired attitude and the current attitude, the attitude controller generates the desired angular velocity. Based on the desired angular velocity and the current body angular velocity, the desired total torque is generated by the angular velocity controller; The desired total force and the desired total torque are input into the control distributor, and the desired thrust of each rotor is obtained by solving the pre-established dynamic model of the rotor configuration of the UAV. Based on the expected thrust of each rotor and the preset thrust-rotation speed correspondence, the expected rotation speed of each rotor is calculated, and the rotation of each rotor is controlled according to the expected rotation speed.

[0006] As a further improvement of the present invention, the generation of the desired total force through the position controller includes: Calculate the position error between the desired position and the current position, perform proportional, integral, and differential operations on the position error in sequence, and superimpose it with the desired acceleration feedforward to obtain the desired acceleration command; Based on the mass of the UAV and the rotation matrix that reflects its current attitude, the acceleration command and gravity vector are converted into the desired total force in the body coordinate system.

[0007] As a further improvement of the present invention, in the integral operation of the position controller, the Euclidean distance between the current position and the desired position is calculated in real time, and when the Euclidean distance is less than a preset first threshold, the cumulative integral value is set to zero.

[0008] As a further improvement of the present invention, the step of generating the desired angular velocity through the attitude controller includes: Calculate the quaternion of the attitude error between the desired attitude and the current attitude; The imaginary part of the attitude error quaternion is proportionally and integrally calculated, and then superimposed with the feedforward command angular velocity after rotation compensation to obtain the desired angular velocity.

[0009] As a further improvement of the present invention, in the integral operation of the attitude controller, each component of the attitude error quaternion is calculated in real time, and when the absolute value of all components is less than a preset second threshold, the cumulative integral value is set to zero.

[0010] As a further improvement of the present invention, the generation of the desired total torque by the angular velocity controller includes: The desired angular acceleration is calculated based on the difference between the desired angular velocity and the current angular velocity of the machine body, combined with a preset time constant. Based on the moment of inertia and current angular velocity of the UAV, the desired total torque is calculated using the Newton-Euler torque balance equation.

[0011] As a further improvement of the present invention, after obtaining the desired rotational speed of each rotor, the method further includes: saturating and limiting the desired rotational speed to make it within a preset allowable rotational speed range, and controlling the rotation of each rotor according to the desired rotational speed after saturation and limiting. The saturation limit is specifically defined as follows: when the calculated desired speed is less than zero, the desired speed is limited to zero; when it is greater than the preset maximum speed, the desired speed is limited to the maximum speed.

[0012] In a second aspect, the present invention provides a tilting rotor omnidirectional unmanned aerial vehicle control system, comprising: The pose acquisition module is used to acquire the current pose information of the UAV, which includes the current position, current attitude and current body angular velocity; The desired pose module is used to acquire desired pose information, which includes desired position and attitude information; The position controller module generates a desired total force based on the desired position and the current position; The attitude controller module generates a desired angular velocity based on the desired attitude and the current attitude; The angular velocity controller module generates the desired total torque based on the desired angular velocity and the current angular velocity of the machine body; The control distribution module inputs the desired total force and the desired total torque into the control distributor, and obtains the desired thrust of each rotor by solving the pre-established dynamic model of the rotor configuration of the UAV. The execution module calculates the desired rotational speed of each rotor based on the desired thrust of each rotor and the preset thrust-rotational speed correspondence, and controls the rotation of each rotor according to the desired rotational speed.

[0013] Thirdly, the present invention provides a computer device, comprising: a processor and a computer-readable storage medium; A processor, adapted to execute computer programs; A computer-readable storage medium storing a computer program that, when executed by the processor, implements the tilting rotor omnidirectional unmanned aerial vehicle control method described above.

[0014] Fourthly, the present invention provides a computer-readable storage medium storing a computer program adapted to be loaded by a processor and executed as described above for the tilting rotor omnidirectional unmanned aerial vehicle control method.

[0015] The beneficial effects of this invention are as follows: This invention provides a tilting rotor omnidirectional UAV control method. By acquiring the current pose information of the UAV (including position, attitude, and body angular velocity) and the desired pose information, the position controller generates the desired total force based on the difference between the desired and current positions. The attitude controller generates the desired angular velocity based on the desired and current attitudes. The angular velocity controller generates the desired total torque based on the desired angular velocity and the current body angular velocity. Finally, the control distributor converts the total force and total torque into the desired thrust of each rotor through the rotor configuration dynamics model, and calculates the desired rotational speed based on the thrust-rotor speed relationship to achieve precise rotor control. The various technical features are interconnected to form a closed-loop control chain. Through the cascaded design of the position-attitude-angular velocity three-level controllers, compared with the single-level or non-cascaded control in the prior art, the decoupling optimization of position control and attitude control is achieved. Among them, the position controller focuses only on the position deviation to generate the total force, avoiding the interference of attitude fluctuations on position control; the attitude controller outputs the desired angular velocity instead of the direct torque, making the attitude adjustment more in line with the dynamic characteristics of the UAV; the angular velocity controller corrects the desired angular velocity based on the current body angular velocity, effectively suppressing angular velocity tracking delay. The three work together to improve the accuracy and response speed of attitude control. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a flowchart of the tilting rotor omnidirectional UAV control method in an embodiment of the present invention; Figure 2 This is a diagram of the tilting rotor omnidirectional UAV control structure in an embodiment of the present invention; Figure 3 This is an internal structural diagram of a computer device in an embodiment of the present invention. Detailed Implementation

[0018] To make the objectives and technical solutions of this invention clearer and easier to understand, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. The specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings and specific embodiments. The described embodiments are only some embodiments of the present invention, and not all embodiments.

[0020] Example 1 Tilted rotor omnidirectional UAVs, as a novel multi-rotor UAV configuration, achieve omnidirectional mobility by changing the tilt angle of their rotors. Compared to traditional multi-rotor UAVs, tilted rotor UAVs offer greater maneuverability and flexibility, enabling them to perform complex flight maneuvers in confined spaces. However, existing UAV control methods are primarily designed for conventional multi-rotor configurations and fail to fully consider the unique dynamic characteristics of tilted rotor UAVs. Specifically, traditional control methods often employ simplified dynamic models when dealing with force and torque distribution in tilted rotor UAVs, resulting in insufficient control precision, slow response speed, and difficulty in fully leveraging the omnidirectional mobility advantages of the tilted rotor. Furthermore, existing technologies suffer from inadequate handling of coupling effects in the connection between position control, attitude control, and angular velocity control, which can easily lead to oscillations and overshoot during the control process, affecting flight stability and safety.

[0021] Based on this, this embodiment discloses a tilting rotor omnidirectional unmanned aerial vehicle (UAV) control method, such as... Figure 1 As shown, the specific implementation method is as follows.

[0022] S1: Obtain the current pose information of the drone, which includes the current position, current attitude, and current angular velocity of the drone.

[0023] Current pose information is fundamental data for UAV control, comprising three core parameters: current position, current attitude, and current body angular velocity. Current position refers to the UAV's coordinate position in three-dimensional space, typically referenced to the Earth coordinate system or local navigation coordinate system, and acquired through satellite positioning systems such as GPS and BeiDou, or visual positioning systems. Current attitude refers to the UAV's rotational state relative to the reference coordinate system, usually expressed in Euler angles, rotation matrices, or quaternions, used to describe the UAV's pitch, roll, and yaw angles. Current body angular velocity refers to the angular velocity components of the UAV's rotation around each axis in the body coordinate system, reflecting the UAV's current rotational motion state. This pose information can be acquired through an onboard sensor system, including fusion of sensors such as accelerometers and gyroscopes in the inertial measurement unit (IMU), magnetometers, barometers, and visual odometry. In some embodiments of this application, the frequency of pose information acquisition should not be lower than the sampling frequency of the control system, typically set to 100Hz to 500Hz, to ensure the real-time performance and accuracy of the control response.

[0024] S2: Obtain the desired pose information, which includes the desired position and orientation information.

[0025] Desired pose information refers to the target state of the UAV control system, including desired position and desired attitude information. The desired position refers to the coordinates of the target position that the UAV should reach, which can be provided by the mission planning system, remote control commands, or autonomous navigation algorithms. The desired attitude refers to the target attitude that the UAV should maintain, which can be a hovering attitude, a forward attitude, or any specified attitude angle. Desired pose information is usually represented in the same coordinate system as the current pose information for ease of subsequent control law calculation. In some embodiments of this application, the desired pose information can be input into the control system through host computer commands, ground station control, or autonomous flight mission planning.

[0026] S3: Based on the desired position and the current position, generate the desired total force through the position controller.

[0027] As some embodiments of this application, such as Figure 2 As shown, the position error between the desired position and the current position is calculated. Proportional, integral, and differential operations are performed on the position error sequentially, and then the result is superimposed with the desired acceleration feedforward to obtain the desired acceleration command. Based on the UAV's mass and the rotation matrix reflecting its current attitude, the acceleration command and gravity vector are converted into the desired total force in the body coordinate system. The desired total force refers to the net external force required for the UAV to achieve the desired motion, acting on the UAV's center of gravity.

[0028] In the integral calculation of the position controller, the Euclidean distance between the current position and the desired position is calculated in real time. When the Euclidean distance is less than a preset first threshold, the accumulated integral value is set to zero. The setting of the first threshold needs to be determined comprehensively based on the control accuracy requirements and the dynamic performance of the system, and is usually set to 1 to 3 times the desired position accuracy. In some embodiments of this application, the first threshold can be set between 0.1 meters and 0.5 meters, and the specific value can be adjusted according to the size of the UAV and the control accuracy requirements.

[0029] Specifically, the input-output relationship of the position controller is shown in the following equation:

[0030] The second derivative in the formula The composition is shown in the following formula:

[0031] In the formula The proportional gain of the position controller. The integral coefficient of the position controller. For the differential coefficients of the position controller, For the time of the drone flight, The error between the body's center of mass and the desired position is calculated using the following formula:

[0032] In the formula This represents the actual location of the drone.

[0033] The integral term in the position controller suffers from an issue where the integral error can increase infinitely due to reasons such as unstable hovering, preventing the drone from perfectly aligning with the target position. Therefore, a corresponding integral error limiting mechanism is designed, which is achieved by obtaining the x-axis difference between the UAV body and the target position in three-dimensional Cartesian coordinates. y-axis difference and z-axis difference Euclidean distance between the computer body and the target position :

[0034] When Euclidean distance When the distance is less than the set threshold, the drone is considered to have reached the target position, and the integration error is set to zero; when the Euclidean distance is less than the set threshold, the drone is considered to have reached the target position, and the integration error is set to zero. If the value is greater than or equal to the set threshold, it is considered that the drone has not yet reached the target position, and the integration error continues to accumulate.

[0035] S4: Based on the desired attitude and the current attitude, generate the desired angular velocity through the attitude controller.

[0036] As one embodiment of this application, the attitude error quaternion between the desired attitude and the current attitude is calculated; the imaginary part of the attitude error quaternion is proportionally and integrally calculated, and then superimposed with the feedforward command angular velocity after rotation compensation to obtain the desired angular velocity. The desired angular velocity refers to the target value of the airframe angular velocity that the UAV needs to achieve to eliminate attitude errors.

[0037] In the integral operation of the attitude controller, each component of the attitude error quaternion is calculated in real time. When the absolute value of all components is less than a preset second threshold, the accumulated integral value is set to zero. The second threshold should be set less than the steady-state error range of the attitude control, typically between 0.01 and 0.05. In some embodiments of this application, the second threshold can be tuned according to the attitude control accuracy requirements and system dynamic performance. When the UAV is hovering or flying at low speed, the second threshold can be appropriately increased to enhance anti-interference capability.

[0038] Specifically, the input-output relationship of the attitude controller is as follows:

[0039] In the formula This is the proportional coefficient of the attitude controller. For the integral coefficients of the attitude controller, According to The calculated rotation matrix The inverse matrix, for The imaginary part, and the sign is the same as... The signs of the real parts are the same.

[0040] The attitude controller's integral term suffers from the problem of its inability to perfectly match the target attitude, leading to an infinitely increasing integral error. Therefore, a corresponding integral error limiting mechanism is designed. In the control system, the UAV's attitude is represented as a unit quaternion. By calculating the differences between the three imaginary parts and one real part of the UAV's real-time attitude unit quaternion and the target attitude unit quaternion, the integral error is obtained from the three imaginary parts. , , and a real part The resulting error quaternion vector:

[0041] when When the absolute value of all elements is less than the set threshold, the drone is considered to have reached the target attitude, and the integral error is set to zero; when If the absolute value of any element is greater than or equal to a set threshold, the drone is considered not to have reached the target attitude, and the integral error continues to accumulate.

[0042] S5: Based on the desired angular velocity and the current body angular velocity, the desired total torque is generated through the angular velocity controller.

[0043] As some embodiments of this application, the detailed implementation of the angular velocity controller includes the following steps: calculating the desired angular acceleration based on the difference between the desired angular velocity and the current body angular velocity, combined with a preset time constant; calculating the desired total torque using the Newton-Euler torque balance equation based on the UAV's moment of inertia and the current body angular velocity. The desired angular acceleration is obtained by dividing the difference between the desired angular velocity and the current body angular velocity by the time constant.

[0044] It should be noted that the angular velocity controller is the last controller component in the control chain. Its input is the deviation between the desired angular velocity and the current body angular velocity, and its output is the desired total torque. The desired total torque refers to the net external torque required for the UAV to achieve the desired angular acceleration, acting on the UAV's center of gravity, including roll torque, pitch torque, and yaw torque around the three axes of the body. The design of the angular velocity controller needs to consider the coupling characteristics of the rotational inertia matrix to ensure the accuracy of control commands and response speed.

[0045] Specifically, the input-output relationship of the angular velocity controller is shown in the following equation:

[0046] In the formula This refers to the actual angular velocity of the drone. The calculation expression is shown below:

[0047] In the formula The time constant after approximating this part of the system as a linear time-invariant first-order system.

[0048] S6: Input the desired total force and desired total torque into the control distributor, and obtain the desired thrust of each rotor by solving the pre-established dynamic model of the UAV rotor configuration.

[0049] The dynamic model is a pre-established multi-rotor dynamic equation based on the rotor configuration of the UAV, describing the mapping relationship between the thrust of each rotor and the overall force and torque of the UAV. For tilt-rotor UAVs, since the rotor installation angle is adjustable, the dynamic model needs to consider the force component changes caused by rotor tilt. In some embodiments of this application, the control distributor uses optimization algorithms such as pseudo-inverse method, weighted least squares method, or sequential quadratic programming to solve the above inverse dynamics problem, selecting an appropriate solution method according to the number and configuration characteristics of the rotors. The expected thrust of each rotor refers to the magnitude of the thrust that each rotor should produce, which is the direct command executed by the control.

[0050] As one embodiment of this application, the dynamic model is modeled as follows:

[0051]

[0052] In the formula The total mass of the omnidirectional drone, Location of the drone The second derivative, For drones from inertial frame To machine system rotation matrix The inverse matrix, The total force generated by the drone It is the acceleration due to gravity. Let the moment of inertia of the drone be... Angular velocity of the drone body The first derivative, The total torque generated by the drone; the first equation in the Newton-Euler equations is the force balance equation, and the second equation is the torque balance equation.

[0053] S7: Calculate the desired rotational speed of each rotor based on the desired thrust of each rotor and the preset thrust-rotational speed correspondence, and control the rotation of each rotor according to the desired rotational speed.

[0054] The thrust-speed correlation is a mathematical model describing the relationship between the input speed and output thrust of a rotor motor. It is typically obtained through calibration experiments and can be expressed as a linear or polynomial relationship. The desired speed refers to the rotor motor speed required to generate the desired thrust, calculated based on the thrust-speed correlation. After obtaining the desired speed, the control system converts it into motor control signals and outputs them to each rotor motor driver, achieving closed-loop control of the rotor speed.

[0055] As one embodiment of this application, the design of the omnidirectional UAV position controller is based on the force balance equation in the Newton-Euler equations, and a PID algorithm closed-loop control is introduced to calculate the second derivative of the position. The desired total force is the input to the controller. As the output of the controller Expected total force and the expected total torque Force generated by the rotor The relationship is as follows:

[0056] The control distributor will solve the above equation using a pseudo-inverse matrix. The matrix M is defined as follows:

[0057] For matrix Find its pseudo-inverse matrix The thrust generated by the rotor can be obtained through pseudo-inverse operation. As shown in the following formula:

[0058] The desired rotational speed of each rotor-driven rotor of the UAV can then be calculated using the following formula. :

[0059]

[0060] In the formula The single-propeller combined thrust coefficient of the rotor. This is the combined torque coefficient of the rotor's single propeller; In addition, after obtaining the desired rotational speed of each rotor, this application further includes: saturating and limiting the desired rotational speed to make it within a preset allowable rotational speed range, and controlling the rotation of each rotor according to the desired rotational speed after saturation and limiting; The saturation limit specifically means: when the calculated desired speed is less than zero, the desired speed is limited to zero; when it is greater than the preset maximum speed, the desired speed is limited to the maximum speed. The saturation limit is a protective measure to prevent the motor and rotor from exceeding their safe operating range. The speed of the motor and rotor has physical limitations; excessively high or low speeds can lead to performance degradation or equipment damage. Specifically, the saturation limit includes the following rules: when the calculated desired speed is less than zero, the desired speed is limited to zero; when the desired speed is greater than the preset maximum speed, the desired speed is limited to the maximum speed.

[0061] The propellers used in omnidirectional drones are unidirectional, therefore their rotational speed must be greater than or equal to 0, and cannot exceed the maximum rotational speed. Therefore, to ensure the normal operation of the UAV rotor, a speed saturation circuit is designed in the control distributor to limit the speed; when the desired rotor rotation speed is negative, it is constrained to 0, and when the desired rotor rotation speed exceeds the maximum speed... At that time, constrain it to the maximum speed. As shown in the following formula:

[0062] This forced constraint method relies on the adaptability of the overall UAV control system to gradually adjust the speed distribution of each rotor.

[0063] Within the omnidirectional UAV, the attitude controller and body angular velocity controller are in parallel with the position controller; the attitude controller and body angular velocity controller form a cascaded structure, with the attitude controller as the main controller and the body angular velocity controller as the secondary controller, performing feedback closed-loop control based on the omnidirectional UAV attitude information collected by the selected sensors.

[0064] This application calculates the desired pose of an omnidirectional UAV in real time and uses the pose information obtained by the UAV's onboard sensors as feedback to the position and attitude controllers, which are based on PID algorithms. In addition, the integral error is also limited. Then, the output of the attitude controller is transmitted to the body angular velocity controller, and the desired force and torque of the UAV calculated by the position controller and the body angular velocity controller are transmitted to the control distributor. Finally, the control distributor maps the desired force and torque to the required rotational angular velocity of each rotor of the UAV and introduces a saturation element to limit its rotational speed. Based on the pose change of the UAV caused by the rotor speed, the control method is recalculated, thus forming a closed-loop control of the omnidirectional UAV.

[0065] Example 2 This embodiment discloses a tilting rotor omnidirectional unmanned aerial vehicle (UAV) control system, including a pose acquisition module, a desired pose module, a position controller module, an attitude controller module, an angular velocity controller module, a control allocation module, and an execution module.

[0066] The pose acquisition module is used to acquire the current pose information of the UAV, including communication functions with the sensor system interface. It can receive and process raw data from sensors such as IMU, GPS, and barometer, and obtain high-precision pose estimation results through sensor fusion algorithms. The output of the pose acquisition module serves as the input to the position controller module and attitude controller module.

[0067] The desired pose module is used to acquire desired pose information. It can communicate with the task planning system, remote control receiver or host computer interface to receive desired position and desired attitude commands, and transmit the desired pose information to the corresponding controller module.

[0068] The position controller module generates a desired total force based on the deviation between the desired position and the current position, thereby controlling the position of the UAV. The position controller module can be specifically implemented according to the descriptions in Embodiments 2 and 3, including a proportional-integral-derivative control law and anti-integral saturation measures.

[0069] The attitude controller module generates a desired angular velocity based on the deviation between the desired attitude and the current attitude, thereby controlling the attitude of the UAV. The attitude controller module can be specifically implemented according to the descriptions in Embodiments 4 and 5, including quaternion-based control laws and conditional integral measures.

[0070] The angular velocity controller module generates a desired total torque based on the deviation between the desired angular velocity and the current body angular velocity, thereby controlling the angular velocity of the UAV. The angular velocity controller module can be specifically implemented according to the description in Embodiment Six, including a torque balance control law based on the Newton-Euler equations.

[0071] The control and distribution module takes the desired total force and desired total torque as inputs and obtains the desired thrust of each rotor by solving a pre-established dynamic model. The implementation of the control and distribution module requires establishing dynamic equations based on the specific rotor configuration of the UAV and employing appropriate numerical solution methods.

[0072] The execution module calculates the desired rotational speed based on the desired thrust of each rotor and the preset thrust-speed correspondence, and sends the control command to the motor driver after saturation limiting. The execution module may also include a motor drive circuit and PWM signal generation function to realize closed-loop control of the rotor motor speed.

[0073] Specific limitations regarding the tilt rotor omnidirectional UAV control system can be found in the limitations of the tilt rotor omnidirectional UAV control method described above, and the corresponding technical effects are equivalent, so they will not be repeated here. Each module in the aforementioned tilt rotor omnidirectional UAV control system can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device, or stored in the memory of a computer device as software, so that the processor can call and execute the corresponding operations of each module.

[0074] Example 3 Figure 3 An internal structural diagram of a computer device is shown in one embodiment. This computer device may specifically be a terminal or a server. Figure 3 As shown, the computer device includes a processor, memory, network interface, display, camera, and input device connected via a system bus. The processor provides computing and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system and computer programs. The internal memory provides an environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The network interface is used to communicate with external terminals via a network connection. When the computer program is executed by the processor, it implements a tilting rotor omnidirectional UAV control method. The display screen can be an LCD screen or an e-ink display screen. The input device can be a touch layer covering the display screen, buttons, a trackball, or a touchpad mounted on the computer device casing, or an external keyboard, touchpad, or mouse.

[0075] As will be understood by those skilled in the art, computer equipment Figure 3 The structure shown is merely a block diagram of a portion of the structure related to the present invention and does not constitute a limitation on the computer device to which the present invention is applied. A specific computing device may include more or fewer components than those shown in the figure, or combine certain components, or have the same component arrangement.

[0076] In one embodiment, a computer device is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, wherein the processor executes the computer program to implement the steps of the method described above.

[0077] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon, which, when executed by a processor, implements the steps of the above-described method.

[0078] In summary, the tilt rotor omnidirectional UAV control method, system, computer device, and storage medium provided in this application establish a hierarchical closed-loop control method to address the overdrive characteristics of tilt rotor omnidirectional UAVs. By employing PID control with error integral constraints in both the position and attitude loops, and integrating torque calculation based on the Newton-Euler equations into the angular velocity loop, precise decoupling of force and attitude and rapid response are achieved. The control allocation stage introduces a pseudo-inverse matrix to analytically allocate the desired force and torque, coupled with physical saturation constraints on rotational speed, satisfying both the real-time allocation requirements of the overdrive system and ensuring actuator safety. In particular, the integral constraint mechanisms designed based on Euclidean distance and error quaternion components in the position and attitude controllers completely solve the saturation problem caused by the continuous accumulation of small steady-state errors in traditional integral control, resulting in higher robustness and stability for the UAV in hovering and precise trajectory tracking. The overall technical solution has a clear structure, low computational complexity, and is easy to deploy on low-cost embedded flight control hardware, significantly promoting the transition of tilt rotor omnidirectional UAVs from theoretical configuration to reliable practical flight.

[0079] The various embodiments in this specification are described in a progressive manner. For directly identical or similar parts of the embodiments, refer to each other. Each embodiment focuses on its differences from other embodiments. In particular, the system embodiments are basically similar to the method embodiments, so the description is relatively simple; relevant parts can be referred to the descriptions in the method embodiments. It should be noted that the technical features of the above embodiments can be combined arbitrarily. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as the combination of these technical features does not contradict each other, it should be considered within the scope of this specification.

[0080] The above-described embodiments are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they should not be construed as limiting the scope of the invention. It should be noted that those skilled in the art can make various improvements and substitutions without departing from the principles of the present invention, and these improvements and substitutions should also be considered within the scope of protection of the present invention. Therefore, the scope of protection of this invention should be determined by the scope of the claims.

Claims

1. A method for controlling an omnidirectional unmanned aerial vehicle with a tilting rotor, characterized in that, include: Obtain the current pose information of the UAV, which includes the current position, current attitude, and current angular velocity of the UAV. Obtain desired pose information, which includes desired position and orientation information; Based on the desired position and the current position, the desired total force is generated by the position controller; Based on the desired attitude and the current attitude, the attitude controller generates the desired angular velocity. Based on the desired angular velocity and the current body angular velocity, the desired total torque is generated by the angular velocity controller; The desired total force and the desired total torque are input into the control distributor, and the desired thrust of each rotor is obtained by solving the pre-established dynamic model of the rotor configuration of the UAV. Based on the expected thrust of each rotor and the preset thrust-rotation speed correspondence, the expected rotation speed of each rotor is calculated, and the rotation of each rotor is controlled according to the expected rotation speed.

2. The tilting rotor omnidirectional UAV control method according to claim 1, characterized in that, The generation of the desired total force via the position controller includes: Calculate the position error between the desired position and the current position, perform proportional, integral, and differential operations on the position error in sequence, and superimpose it with the desired acceleration feedforward to obtain the desired acceleration command; Based on the mass of the UAV and the rotation matrix that reflects its current attitude, the acceleration command and gravity vector are converted into the desired total force in the body coordinate system.

3. The tilting rotor omnidirectional UAV control method according to claim 2, characterized in that, In the integral operation of the position controller, the Euclidean distance between the current position and the desired position is calculated in real time. When the Euclidean distance is less than a preset first threshold, the cumulative integral value is set to zero.

4. The tilting rotor omnidirectional UAV control method according to claim 1, characterized in that, The process of generating the desired angular velocity through the attitude controller includes: Calculate the quaternion of the attitude error between the desired attitude and the current attitude; The imaginary part of the attitude error quaternion is proportionally and integrally calculated, and then superimposed with the feedforward command angular velocity after rotation compensation to obtain the desired angular velocity.

5. The tilting rotor omnidirectional UAV control method according to claim 4, characterized in that, In the integral operation of the attitude controller, each component of the attitude error quaternion is calculated in real time. When the absolute value of all components is less than a preset second threshold, the cumulative integral value is set to zero.

6. The tilting rotor omnidirectional UAV control method according to claim 1, characterized in that, The generation of the desired total torque via the angular velocity controller includes: The desired angular acceleration is calculated based on the difference between the desired angular velocity and the current angular velocity of the machine body, combined with a preset time constant. Based on the moment of inertia and current angular velocity of the UAV, the desired total torque is calculated using the Newton-Euler torque balance equation.

7. The tilting rotor omnidirectional unmanned aerial vehicle control method according to any one of claims 1 to 6, characterized in that, After obtaining the desired rotational speed of each rotor, the method further includes: saturating and limiting the desired rotational speed to keep it within a preset allowable rotational speed range, and controlling the rotation of each rotor according to the desired rotational speed after saturation and limiting. The saturation limit is specifically defined as follows: when the calculated desired speed is less than zero, the desired speed is limited to zero; when it is greater than the preset maximum speed, the desired speed is limited to the maximum speed.

8. A tilting rotor omnidirectional unmanned aerial vehicle control system, characterized in that, include: The pose acquisition module is used to acquire the current pose information of the UAV, which includes the current position, current attitude and current body angular velocity; The desired pose module is used to acquire desired pose information, which includes desired position and attitude information; The position controller module generates a desired total force based on the desired position and the current position; The attitude controller module generates a desired angular velocity based on the desired attitude and the current attitude; The angular velocity controller module generates the desired total torque based on the desired angular velocity and the current angular velocity of the machine body; The control distribution module inputs the desired total force and the desired total torque into the control distributor, and obtains the desired thrust of each rotor by solving the pre-established dynamic model of the rotor configuration of the UAV. The execution module calculates the desired rotational speed of each rotor based on the desired thrust of each rotor and the preset thrust-rotational speed correspondence, and controls the rotation of each rotor according to the desired rotational speed.

9. A computer device, characterized in that, include: Processor and computer-readable storage media; A processor, adapted to execute computer programs; A computer-readable storage medium storing a computer program, which, when executed by the processor, implements the tilting rotor omnidirectional unmanned aerial vehicle control method as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program adapted to be loaded by a processor and executed as described in any one of claims 1 to 7.

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