Aircraft flight control method, apparatus and medium

Abstract

The application discloses a flight control method and device of an aircraft and a medium, and is suitable for the technical field of the aircraft. The current sinking rate and forward flight speed of the aircraft are used to complete control on the lift value and attitude trim moment of the aircraft, the lift value and attitude trim moment are superimposed and distributed to obtain total pitch values of power systems of each propeller, then when the aircraft height satisfies a preset condition, each total pitch value is adjusted to reduce the vertical speed, and when the speed and height satisfy certain conditions, the aircraft attitude is adjusted to a target attitude to complete the aircraft attitude preparation before landing for landing. After the power system of the aircraft fails, stable glide is maintained, the propeller rotating speed in the unpowered state is adjusted through variable total pitch, and then the pulling force of the propeller is changed, so that the sinking rate and attitude of the aircraft in the power failure state are controlled, the disadvantages that the glide handling strategy cannot be implemented in the low-speed and stall states are made up, and additional emergency handling devices such as parachutes are not needed.

Description

Technical Field

[0001] This invention relates to the field of aircraft technology, and in particular to a flight control method, device and medium for aircraft. Background Technology

[0002] In recent years, with the development of materials, energy and control technologies, the feasibility of electric vertical takeoff and landing (eVTOL) aircraft has been fully demonstrated. This aircraft combines the advantages of fixed-wing and multi-rotor aircraft. It has low noise and safety during operation, is suitable for operation in cities, and has broad development prospects.

[0003] If the power system fails during flight, one of the main solutions is to land by gliding. Figure 1 A schematic diagram of the flight profile of an existing eVTOL aircraft, such as Figure 1 As shown, its drawback is that the air glide descent strategy fails at low speeds or in a stall state. Another option is to use a parachute, but this adds extra weight and results in additional energy loss.

[0004] Therefore, how to avoid the failure of the air glide landing strategy and reduce energy consumption under low-speed stall conditions is a problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] The purpose of this invention is to provide a flight control method, device, and medium for an aircraft. By adjusting the propeller speed in a powerless state through variable collective pitch, the propeller thrust is changed, thereby controlling the sink rate and attitude of the aircraft in a power failure state. This overcomes the shortcomings of existing air glide handling strategies that cannot be implemented in low-speed and stall states. At the same time, it eliminates the need for additional devices (parachute devices) to deal with in-flight power system failures, reducing the energy consumption of the aircraft.

[0006] To solve the above-mentioned technical problems, the present invention provides a flight control method for an aircraft, comprising:

[0007] The current sink rate, forward velocity, and flight altitude of the aircraft are obtained, and the corresponding lift and attitude trim moment values ​​are determined based on the current sink rate and forward velocity values, respectively.

[0008] The lift value and the attitude trim moment value are superimposed and distributed to obtain the collective pitch value of each propeller of the aircraft.

[0009] When the flight altitude value meets the first preset condition, adjust each of the collective distance values ​​to obtain the corresponding vertical velocity value;

[0010] When the vertical velocity value, the forward velocity value, and the flight altitude value after adjusting each of the collective distance values ​​meet the second preset condition, the attitude trim moment value is adjusted to the target moment value of the target attitude for landing, wherein the satisfied altitude value of the flight altitude value within the first preset condition is greater than the satisfied altitude value of the flight altitude value after adjusting each of the collective distance values ​​within the second preset condition.

[0011] Preferably, before obtaining the current sink rate, forward velocity, and flight altitude of the aircraft, the method further includes:

[0012] Obtain the health status information of the aircraft's power system;

[0013] When the health status information indicates a fault state, the aircraft enters the autorotation descent state.

[0014] The aircraft is initialized, and the process proceeds to the step of obtaining the current sink rate, forward velocity, flight altitude, and vertical velocity of the aircraft. The initialization operation includes at least disconnecting the mechanical connection of the power system, reducing the collective pitch of each propeller, and initializing the attitude trim torque.

[0015] Preferably, the step of superimposing and distributing the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft includes:

[0016] The first torque value is obtained by weighting and superimposing the lift value and the attitude trim torque value.

[0017] The collective pitch value of each propeller is determined based on the correspondence between the first torque value and the allocation matrix.

[0018] Preferably, the forward velocity value includes the current forward velocity value and the target forward velocity value. Determining the corresponding attitude trim moment value based on the forward velocity value includes:

[0019] Obtain the current forward acceleration value of the aircraft;

[0020] The first forward velocity value is obtained by subtracting the current forward velocity value and the target forward velocity value.

[0021] A second forward speed value is obtained by applying speed limiting processing to the first forward speed value.

[0022] The target acceleration value is obtained by processing the second forward velocity value using a PID controller.

[0023] The first acceleration value is obtained by subtracting the current forward acceleration value from the target acceleration value.

[0024] The first acceleration value is subjected to acceleration limiting processing to obtain the second acceleration value;

[0025] The attitude trimming torque value is obtained by processing the second acceleration value using the arctangent function.

[0026] Correspondingly, determining the corresponding lift value based on the current sinking rate includes:

[0027] Obtain the mapping relationship between subsidence rate and tensile force;

[0028] The corresponding lift value is determined based on the current sinking rate and the mapping relationship between the sinking rate and the tension.

[0029] Preferably, the first preset condition is that the flight altitude of the aircraft is less than or equal to the pull-up deceleration altitude, and adjusting each of the collective pitch values ​​to obtain the corresponding vertical velocity value includes:

[0030] Determine whether the flight altitude value is less than or equal to the pull-up deceleration altitude value;

[0031] If so, then the flight altitude value is determined to satisfy the first preset condition;

[0032] Based on the total distance values, each of the aforementioned total distance values ​​is adjusted according to the preset total distance value within the single-shot time step;

[0033] The corresponding vertical velocity value is obtained based on the adjusted total distance.

[0034] Preferably, the second preset condition is that the vertical velocity value, the forward velocity value, and the flight altitude value are respectively less than or equal to the corresponding preset vertical velocity value, preset forward velocity value, and preset altitude value, wherein the preset altitude value is less than the pull-up deceleration altitude value, the attitude trim moment includes pitch attitude trim moment, roll attitude trim moment, and yaw attitude trim moment, and the target moment value for adjusting to the target attitude according to the attitude trim moment value includes:

[0035] Determine whether the vertical velocity value, the forward velocity value, and the flight altitude value are respectively less than or equal to the corresponding preset vertical velocity value, the preset forward velocity value, and the preset altitude value;

[0036] If so, then the vertical velocity value, the forward velocity value, and the flight altitude value are determined to satisfy the second preset condition;

[0037] Obtain the attitude torque command corresponding to the target attitude, wherein the attitude torque command includes instructions for attitude torque adjustment parameters;

[0038] Adjust the attitude trimming torque value to the target torque value according to the attitude torque command;

[0039] Correspondingly, the process of acquiring the attitude moment command specifically includes: acquiring the current pitch angle, current roll angle, current yaw angle, target pitch angle, target roll angle, and target yaw angle corresponding to each trim moment value;

[0040] The first angular rate is obtained by subtracting the current pitch angle from the target pitch angle, the current roll angle from the target roll angle, the current yaw angle from the target yaw angle, and the current yaw angle from the target yaw angle.

[0041] Each of the first angular velocities is subjected to angular rate limiting processing to obtain the corresponding second angular rate;

[0042] The attitude torque adjustment parameters are obtained by processing each of the second angular velocities using a PID controller.

[0043] The attitude torque adjustment parameters are used to generate the corresponding attitude torque command.

[0044] Preferably, before the step of superimposing and distributing the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft, and after the step of determining the corresponding lift value and attitude trim moment value according to the current sink rate and the forward velocity value, the method further includes:

[0045] The attitude trim moment value is subjected to amplitude limiting processing to obtain the processed attitude moment value, and then proceeds to the step of superimposing and distributing the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft.

[0046] To solve the above-mentioned technical problems, the present invention also provides a flight control device for an aircraft, comprising:

[0047] The acquisition module is used to acquire the current sink rate, forward velocity value and flight altitude value of the aircraft, and determine the corresponding lift value and attitude trim moment value according to the current sink rate and forward velocity value respectively;

[0048] The processing module is used to superimpose and distribute the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft;

[0049] The first adjustment module is used to adjust each of the collective distance values ​​to obtain the corresponding vertical velocity value when the flight altitude value meets the first preset condition.

[0050] The second adjustment module is used to adjust the attitude trim torque value to the target torque value of the target attitude for landing when the vertical velocity value, the forward velocity value, and the flight altitude value after adjusting each of the collective distance values ​​meet the second preset condition. The satisfied altitude value of the flight altitude value within the first preset condition is greater than the satisfied altitude value of the flight altitude value after adjusting each of the collective distance values ​​within the second preset condition.

[0051] To solve the above-mentioned technical problems, the present invention also provides a flight control device for an aircraft, comprising:

[0052] Memory, used to store computer programs;

[0053] A processor is used to execute the computer program to implement the steps of the flight control method for the aircraft as described above.

[0054] To address the aforementioned technical problems, the present invention also provides a computer-readable storage medium storing a computer program, which, when executed by a processor, implements the steps of the flight control method for an aircraft as described above.

[0055] The present invention provides a flight control method for an aircraft, comprising: acquiring the current sink rate, forward velocity, and flight altitude of the aircraft, and determining the corresponding lift and attitude trim moment values ​​based on the current sink rate and forward velocity values ​​respectively; superimposing and distributing the lift and attitude trim moment values ​​to obtain the collective pitch values ​​of each propeller of the aircraft; when the flight altitude value meets a first preset condition, adjusting each collective pitch value to obtain the corresponding vertical velocity value; when the vertical velocity value, forward velocity value, and flight altitude value after adjusting each collective pitch value meet a second preset condition, adjusting the attitude trim moment value to the target moment value of the target attitude for landing, wherein the satisfied altitude value of the flight altitude value under the first preset condition is greater than the satisfied altitude value of the flight altitude value after adjusting each collective pitch value under the second preset condition. This method controls the aircraft's lift and attitude trim moments by using the aircraft's current descent rate and forward velocity. The lift and attitude trim moments are superimposed and distributed to obtain the collective pitch of each propeller's power system. Then, once the aircraft's altitude meets preset conditions, the collective pitch is adjusted to reduce vertical velocity. When speed and altitude meet certain conditions, the aircraft's attitude is adjusted to the target attitude to complete the pre-landing attitude preparation for landing. To maintain stable descent after power system failure, the propellers can use variable pitch. By adjusting the collective pitch, the propeller speed in the powerless state is changed, thereby altering the propeller thrust to control the aircraft's descent rate and attitude in the power failure state. This overcomes the shortcomings of existing air glide handling strategies that cannot be implemented at low speeds and stalls, and eliminates the need for additional devices (parachute devices) to handle in-flight power system failure, reducing energy consumption for aircraft operation.

[0056] In addition, the present invention also provides a flight control device and medium for an aircraft, which has the same beneficial effects as the flight control method for the aircraft described above. Attached Figure Description

[0057] To more clearly illustrate the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0058] Figure 1 A schematic diagram of the flight profile of an existing eVTOL aircraft;

[0059] Figure 2 A flowchart of a flight control method for an aircraft provided in an embodiment of the present invention;

[0060] Figure 3 A schematic diagram illustrating the autorotation and descent process of an aircraft, provided as an embodiment of the present invention;

[0061] Figure 4 A schematic diagram of the autorotation glide control principle of an aircraft provided in an embodiment of the present invention;

[0062] Figure 5 This is a schematic diagram of the autorotation and descent process of an aircraft provided in an embodiment of the present invention;

[0063] Figure 6 A flowchart illustrating the functional implementation of a self-rotating glide phase switching control module provided in an embodiment of the present invention;

[0064] Figure 7 A flowchart illustrating the functional implementation of a self-rotating downward control module provided in an embodiment of the present invention;

[0065] Figure 8 A schematic diagram of a speed controller in a self-rotating glide control module provided in an embodiment of the present invention;

[0066] Figure 9 A schematic diagram of a collective pitch controller in a self-rotating glide control module provided in an embodiment of the present invention;

[0067] Figure 10 A schematic diagram of an attitude controller for a self-rotating glide control module provided in an embodiment of the present invention;

[0068] Figure 11 A structural diagram of a flight control device for an aircraft provided in an embodiment of the present invention;

[0069] Figure 12 This is a structural diagram of another flight control device for an aircraft provided in an embodiment of the present invention. Detailed Implementation

[0070] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present invention.

[0071] The core of this invention is to provide a flight control method, device, and medium for an aircraft. By adjusting the propeller speed in a powerless state through variable collective pitch, the propeller thrust is changed, thereby controlling the sink rate and attitude of the aircraft in a power failure state. This overcomes the shortcomings of existing air glide handling strategies that cannot be implemented in low-speed and stall states. At the same time, it does not require additional devices (parachute devices) to deal with in-flight power system failure, reducing the energy consumption of the aircraft.

[0072] To enable those skilled in the art to better understand the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0073] It should be noted that with the development of eVTOL aircraft both domestically and internationally, and considering the operational scenarios of eVTOL, higher safety requirements are being placed on them. When the power system fails, the traditional air glide method is unusable after the aircraft stalls. If a parachute descent is used, it adds extra weight, and storing parachutes often requires a specialized enclosure, which disrupts the aircraft's shape and increases drag, undoubtedly increasing energy consumption during normal operation. The flight control method for the aircraft provided by this invention can overcome the above-mentioned shortcomings. It utilizes only the aircraft's existing power source, eliminating the need for additional devices to address the problem of in-flight power system failure, thus expanding its application scope and reducing energy consumption for aircraft operation. Furthermore, the aircraft provided by this invention is not only applicable to eVTOL aircraft but also to rotorcraft, helicopters, and other rotorcraft, demonstrating strong universal applicability.

[0074] Figure 2 A flowchart of a flight control method for an aircraft provided in an embodiment of the present invention is shown below. Figure 2 As shown, the method includes:

[0075] S11: Obtain the current sink rate, forward velocity, and flight altitude of the aircraft, and determine the corresponding lift and attitude trim moment values ​​based on the current sink rate and forward velocity values ​​respectively;

[0076] S12: The lift value and attitude trim moment value are superimposed and distributed to obtain the collective pitch value of each propeller of the aircraft;

[0077] S13: When the flight altitude value meets the first preset condition, adjust each collective pitch value to obtain the corresponding vertical speed value;

[0078] S14: When the vertical velocity value, forward velocity value, and flight altitude value after adjusting each collective pitch value meet the second preset condition, adjust the attitude trim moment value to the target moment value of the target attitude to perform landing.

[0079] The flight altitude value within the first preset condition is greater than the flight altitude value after adjusting each collective distance value within the second preset condition.

[0080] Understandably, the autorotation descent of an aircraft is mainly used after a failure in the aircraft's power system. Through appropriate manipulation, the aircraft's gravity-driven energy is converted into the mechanical energy of the propeller. By establishing a stable descent rate, the propeller is driven to generate a stable rotational speed, thereby producing a constant thrust. This allows the aircraft to maintain a stable descent rate after the power system fails. At the same time, during the approach phase, appropriate collective pitch control is used to control the aircraft's forward flight and descent speed, thereby achieving a stable landing.

[0081] Figure 3 This is a schematic diagram of the autorotation and descent process of an aircraft provided as an embodiment of the present invention, as shown below. Figure 3 As shown, the aircraft basically goes through six processes: fault detection, entering autorotation, stabilizing autorotation, pulling up and decelerating, attitude leveling, and landing.

[0082] In the flight control process of this embodiment of the invention, the main task is to acquire the aircraft's flight parameters (current sink rate, forward velocity, and flight altitude, etc.) when a power system failure is detected. Therefore, as an embodiment, before acquiring the aircraft's current sink rate, forward velocity, and flight altitude, the following steps are also included:

[0083] Obtain health status information of the aircraft's propulsion system;

[0084] When the health status information indicates a fault, the aircraft enters the autorotation descent state.

[0085] The aircraft is initialized, and the process proceeds to the steps of acquiring the aircraft's current sink rate, forward velocity, flight altitude, and vertical velocity. The initialization operation includes at least disconnecting the mechanical connection of the power system, reducing the collective pitch of each propeller, and initializing the attitude trim torque.

[0086] Specifically, the health status information of the aircraft's propulsion system is acquired. When the propulsion system malfunctions, i.e., fails, the aircraft enters a gliding state. During this gliding state, initialization settings are performed. These initialization operations primarily include disconnecting the propulsion system power supply and corresponding mechanical connections, reducing propeller collective pitch, and inputting initial attitude trim torque. It is understood that these initialization operations are performed in a specific sequence. In this embodiment, the method for determining the fault state is not limited; as long as a fault is detected by the fault detection module, the propulsion system's health status information is marked as faulty.

[0087] Collective pitch, also known as collective pitch angle, refers to the average pitch of a rotor blade during one revolution. The pilot changes the position of the swashplate using the collective pitch lever. When the swashplate is tilted, the pitch of each blade changes periodically with the azimuth angle; the collective pitch is its average value. Raising the collective pitch lever increases the pitch of all blades by the same amount; conversely, pushing it down decreases the pitch of all blades by the same amount. The helicopter ascends or descends by manipulating the collective pitch lever.

[0088] Step S11 involves acquiring the aircraft's current sink rate, forward velocity, and altitude. The current sink rate is the aircraft's sink speed, the forward velocity is the horizontal forward velocity, and the altitude is the current altitude of the aircraft. Based on the current sink rate and forward velocity, the corresponding lift and attitude trim moment values ​​are determined. Specifically, during the relatively long period of the aircraft's autorotation and descent, the main focus is on controlling the aircraft's lift and attitude trim moment to maintain the propulsion system's rotational speed at a relatively stable level, thereby ensuring a certain sink rate and forward velocity. During this process, a corresponding propeller thrust command is generated based on the sink rate, and the attitude trim moment is generated based on the forward velocity.

[0089] It is understandable that the corresponding thrust value (lift value) is generated based on the sink rate, which can be determined based on a certain mapping relationship between the sink rate and the lift; the attitude trim moment is generated based on the forward velocity value, the attitude is determined based on the velocity, and then the corresponding attitude trim moment is generated based on the attitude.

[0090] In step S12, the lift value and attitude trim moment value are superimposed and allocated to obtain the collective pitch value of each propeller of the aircraft. It should be noted that the collective pitch value of each propeller provided in this embodiment of the invention does not require controlling the collective pitch of different propellers in the event of any rotor power failure, such as controlling the collective pitch of the propeller in the event of power failure of the elevator rotor. In this embodiment, as long as the aircraft experiences power failure, the collective pitch value of each propeller can be obtained by processing the two parameters, lift value and attitude trim moment value. Regarding the superposition and allocation processing, since the collective pitch values ​​of each propeller are different, the corresponding superposition processing can be performed according to different weights or the same fixed ratio. The allocation can also be based on weight ratios or an allocation matrix; no limitation is made here.

[0091] Based on the flight status, the aircraft's altitude is determined. When the altitude meets a first preset condition, the collective pitch values ​​are adjusted. This first preset condition is primarily related to the aircraft's pull-up and deceleration altitude. When the altitude meets a specified value, the aircraft is pulled up and decelerated. Regarding the adjustment of the collective pitch values, it should be noted that the adjustment step size and method differ depending on the first preset condition setting. When the first preset condition is that the flight altitude is less than or equal to the pull-up and deceleration altitude, the collective pitch value needs to be adjusted, requiring a rapid increase in collective pitch, which means a rapid decrease in vertical velocity. There is a mapping relationship between collective pitch values ​​and vertical velocity values, which will not be specifically explained here.

[0092] When the speed and altitude meet the second preset condition—that is, when the vertical speed, forward speed, and the altitude after adjusting the collective pitch values ​​meet the preset conditions—the attitude trim moment value is adjusted to the target moment value for the target attitude. It should be noted that the altitude value after adjusting the collective pitch values ​​within the second preset condition is less than the altitude value within the first preset condition. In other words, after the altitude value meets the altitude corresponding to the first preset condition, the aircraft remains in a descent state. The vertical speed value is obtained after adjusting the collective pitch values, and the vertical speed value, forward speed value, and altitude value after adjusting the collective pitch values ​​meet the second preset condition. The actual altitude value and the altitude value after adjusting the collective pitch values ​​are different. Because the aircraft is in a descent state, the altitude value after adjusting the collective pitch values ​​is less than the actual altitude value. Correspondingly, the altitude value that meets the second preset condition is less than the altitude value that meets the first preset condition. Specifically, when the speed and altitude meet certain conditions, the aircraft enters the attitude trimming phase. During the attitude leveling phase, the aircraft attitude preparation before landing is completed. Attitude torque values ​​are generated through target attitude commands, and the aircraft attitude is adjusted to the target attitude (horizontal attitude, etc.).

[0093] This invention provides a flight control method for an aircraft, comprising: acquiring the current sink rate, forward velocity, and flight altitude of the aircraft, and determining corresponding lift and attitude trim moment values ​​based on the current sink rate and forward velocity; superimposing and distributing the lift and attitude trim moment values ​​to obtain the collective pitch values ​​of each propeller of the aircraft; adjusting each collective pitch value to obtain the corresponding vertical velocity value when the flight altitude value meets a first preset condition; and adjusting the attitude trim moment value to the target moment value of the target attitude to perform landing when the vertical velocity value, forward velocity value, and flight altitude value after adjusting each collective pitch value meet a second preset condition, wherein the altitude value satisfying the flight altitude value under the first preset condition is greater than the altitude value satisfying the flight altitude value after adjusting each collective pitch value under the second preset condition. This method controls the aircraft's lift and attitude trim moments by using the aircraft's current descent rate and forward velocity. The lift and attitude trim moments are superimposed and distributed to obtain the collective pitch of each propeller's power system. Then, once the aircraft's altitude meets preset conditions, the collective pitch is adjusted to reduce vertical velocity. When speed and altitude meet certain conditions, the aircraft's attitude is adjusted to the target attitude to complete the pre-landing attitude preparation for landing. To maintain stable descent after power system failure, the propellers can use variable pitch. By adjusting the collective pitch, the propeller speed in the powerless state is changed, thereby altering the propeller thrust to control the aircraft's descent rate and attitude in the power failure state. This overcomes the shortcomings of existing air glide handling strategies that cannot be implemented at low speeds and stalls, and eliminates the need for additional devices (parachute devices) to handle in-flight power system failure, reducing energy consumption for aircraft operation.

[0094] Based on the above embodiments, step S12, which involves superimposing and distributing the lift value and attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft, includes:

[0095] The first torque value is obtained by weighting and superimposing the lift value and the attitude trim torque value;

[0096] The collective pitch of each propeller is determined based on the correspondence between the first torque value and the distribution matrix.

[0097] Specifically, the first torque value is obtained by weighting and superimposing the lift value and attitude trim torque value, and then the collective pitch value of each propeller is obtained by allocating the first torque value according to the correspondence between the first torque value and the allocation matrix.

[0098] As one embodiment, the forward velocity value includes the current forward velocity value and the target forward velocity value. Step S11, determining the corresponding attitude trim moment value based on the forward velocity value, includes:

[0099] Obtain the current forward acceleration value of the aircraft;

[0100] The first forward velocity value is obtained by subtracting the current forward velocity value from the target forward velocity value.

[0101] The second forward speed value is obtained by applying speed limiting processing to the first forward speed value.

[0102] The target acceleration value is obtained by processing the second forward velocity value using a PID controller.

[0103] The first acceleration value is obtained by subtracting the current forward acceleration value from the target acceleration value.

[0104] The second acceleration value is obtained by applying acceleration limiting to the first acceleration value;

[0105] The arctangent function is called to process the second acceleration value to obtain the attitude trimming torque value;

[0106] Correspondingly, the lift value is determined based on the current sinking rate, including:

[0107] Obtain the mapping relationship between sinking rate and tensile force;

[0108] The corresponding lift value is determined based on the current sinking rate and the mapping relationship between sinking rate and tension.

[0109] Figure 4 A schematic diagram of the autorotation glide control principle of an aircraft provided in an embodiment of the present invention, as shown below. Figure 4 As shown, it includes four parts: target control command generation function, power system fault detection function, flight status detection function, and autorotation glide control function, which correspond to the target control command generation module 2, power system fault detection module 1, flight status detection module 3, and autorotation glide control module 4, respectively. Figure 5 This is a schematic diagram of the autorotation and descent process of an aircraft provided in an embodiment of the present invention, as shown below. Figure 5 As shown:

[0110] The power system fault detection module 1 primarily determines the health status of the aircraft's power system by real-time monitoring of the motor or propeller speeds. Upon detecting a power system fault, it immediately sets the power system health status to FALSE and then sends this status to the autorotation glide control module for autorotation glide control.

[0111] The target control command generation module 2 is mainly responsible for generating target control commands for different stages after the aircraft enters the autorotation and descent phase. The target control commands can be set manually or use default settings.

[0112] Flight status detection module 3 is mainly responsible for detecting information such as the aircraft's flight speed, altitude, and attitude, and transmitting the detected information to the autorotation descent control module for determining the status and switching conditions of the autorotation descent phase.

[0113] Self-rotation and downward sliding control module 4, Figure 6 The flowchart illustrating the functional implementation of a rotation-glide phase switching control module provided in this embodiment of the invention mainly consists of five modules: rotation initialization module 5, rotation stabilization module 6, pull-up deceleration module 7, attitude leveling module 8, and landing module 9. Figure 4 and 6 As shown, the aircraft automatically calls different controllers during different autorotation and descent phases. Figure 7 A flowchart illustrating the functional implementation of a self-rotating glide control module provided in an embodiment of the present invention is shown below. Figure 7 As shown, different control modules correspond to different stages. During the autorotation descent initialization, stable autorotation descent, and pull-up deceleration stages, the speed controller module, attitude control module, and collective pitch control module all need to be called. During the attitude leveling stage, only the attitude control module and collective pitch control module need to be called. And during the landing stage, only the collective pitch control module needs to be called.

[0114] In step S11, the corresponding attitude trim torque value is determined based on the forward airspeed value. Figure 8 A schematic diagram of a speed controller in a self-rotating glide control module provided in an embodiment of the present invention is shown below. Figure 8 As shown, the forward speed value in this embodiment includes the current forward speed value and the target forward speed value. The difference between the current forward speed value and the target forward speed value is calculated to obtain the first forward speed value. The first forward speed value is subjected to speed limiting processing to obtain the second forward speed value. The second forward speed value is then processed by the PID controller to obtain the target acceleration value.

[0115] After obtaining the target acceleration value, the difference between the current forward acceleration value and the target acceleration value is used to obtain the first acceleration value. After amplitude limiting, the second acceleration value is obtained. The arctangent function is called to process the second acceleration value to obtain the attitude trim torque value.

[0116] like Figure 8 As shown, taking longitudinal velocity channel control as an example, the main process involves subtracting the target velocity command provided by the target control command module from the forward velocity detected during the flight state detection phase, followed by amplitude limiting. Then, a proportional-integral-differential (PID) controller is used to obtain the target acceleration command for the aircraft. Finally, after amplitude limiting, the acceleration command is converted into a target attitude control command using an arctangent function.

[0117] Figure 9 A schematic diagram of the collective pitch controller in a self-rotating glide control module provided in an embodiment of the present invention is shown below. Figure 9 As shown, based on the target heave rate provided by the target control command module, the command is mapped from heave rate to thrust and then combined with the target attitude torque command provided by the attitude control module to perform an allocation matrix operation, thereby obtaining the collective pitch control command for all power modules of the distributed propulsion system. The heave rate-thrust mapping relationship is obtained, and the corresponding lift value is determined based on the current heave rate and the heave rate-thrust mapping relationship. Then, the lift value and the attitude trim torque value are weighted and superimposed to obtain the first torque value; the collective pitch value of each propeller is determined based on the correspondence between the first torque value and the allocation matrix.

[0118] Based on the above embodiments, in order to prevent excessive collective pitch from causing the propellers to stop, it is necessary to limit the attitude torque trim value. As one embodiment, before obtaining the collective pitch value of each propeller of the aircraft by superimposing and distributing the lift value and attitude trim torque value, after determining the corresponding lift value and attitude trim torque value according to the current sink rate and forward velocity value, it also includes:

[0119] The attitude trim moment value is limited to obtain the processed attitude moment value, and then proceeds to the step of superimposing and distributing the lift value and attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft.

[0120] Specifically, when calculating the attitude moment trim value, a certain amplitude limitation is applied to prevent it from contributing too much to the propeller collective pitch control. The amplitude limitation processing of the attitude moment trim value is based on the same principle as the amplitude limitation processing in the above embodiments, only the object of amplitude limitation processing is different.

[0121] The collective pitch determination process provided in this embodiment of the invention introduces a variable pitch propeller to ensure that the aircraft can successfully perform autorotation glide control after the failure of the in-flight propulsion system.

[0122] Based on the above embodiments, the first preset condition is that the flight altitude of the aircraft is less than or equal to the pull-up deceleration altitude. Adjusting each collective pitch value to obtain the corresponding vertical velocity value includes:

[0123] Determine if the flight altitude value is less than or equal to the pull-up deceleration altitude value;

[0124] If so, then the flight altitude value is determined to meet the first preset condition;

[0125] Based on each total distance value, adjust each total distance value according to the preset total distance value within the single shot time step;

[0126] The corresponding vertical velocity value is obtained based on the adjusted collective distance.

[0127] Specifically, if the flight altitude is determined to be less than or equal to the pull-up deceleration altitude, the aircraft is initiated into the pull-up deceleration module to pull up and decelerate. Simultaneously, the collective pitch needs to be rapidly increased, corresponding to an increase in the preset collective pitch value within a single time step to adjust the collective pitch values ​​of each propeller. The corresponding vertical velocity value is then obtained based on the adjusted collective pitch value. It should be noted that rapidly increasing the collective pitch value also means rapidly decreasing the vertical velocity value.

[0128] Correspondingly, the preset collective distance value within a single time step is determined based on the attitude and sinking rate. It can be set according to the actual situation. The preset collective distance value within each single time step can be the same, or the preset collective distance value within each time step can be different. The corresponding adjustments of each propeller can also be the same or different, and there is no limitation here.

[0129] During the pull-up deceleration process, if the aforementioned altitude meets certain conditions, the speed is further assessed. As one embodiment, the second preset condition is that the vertical speed value, forward speed value, and flight altitude value are respectively less than or equal to the corresponding preset vertical speed value, preset forward speed value, and preset altitude value, wherein the preset altitude value is less than the pull-up deceleration altitude value. The attitude trim moment includes pitch attitude trim moment, roll attitude trim moment, and yaw attitude trim moment. The target moment value for adjusting to the target attitude based on the attitude trim moment value includes:

[0130] Determine whether the vertical speed value, forward speed value, and flight altitude value are less than or equal to the corresponding preset vertical speed value, preset forward speed value, and preset altitude value, respectively;

[0131] If so, then the vertical velocity value, forward velocity value, and flight altitude value are determined to meet the second preset condition;

[0132] Obtain the attitude torque command corresponding to the target attitude, wherein the attitude torque command includes instructions for attitude torque adjustment parameters;

[0133] Adjust the attitude trimming torque value to the target torque value according to the attitude torque command;

[0134] Correspondingly, the process of acquiring attitude moment commands specifically includes: acquiring the current pitch angle, current roll angle, current yaw angle, target pitch angle, target roll angle, and target yaw angle corresponding to each trim moment value;

[0135] The first angular rate is obtained by subtracting the current pitch angle from the target pitch angle, the current roll angle from the target roll angle, the current yaw angle from the target yaw angle, and so on.

[0136] The corresponding second angular rate is obtained by performing angular rate limiting on each first angular rate;

[0137] The attitude torque adjustment parameters are obtained by processing each second angular rate through a PID controller.

[0138] Generate the corresponding attitude torque command by adjusting the attitude torque parameters.

[0139] Specifically, the speed includes vertical speed and forward speed. When both speed and altitude values ​​meet the second preset condition, the target attitude can be adjusted. During the adjustment process, the target attitude includes pitch, roll, and yaw attitudes. This embodiment adjusts all three attitude types. It should be noted that attitude torque is detected in real time, and the attitude torque adjustment parameters are constantly updated. Once the speed and altitude meet certain preset conditions, an attitude torque command is obtained, and the attitude trim torque value is adjusted to the target torque value according to this command.

[0140] The process of obtaining attitude moment values ​​is as follows: based on the current pitch angle, current roll angle, current yaw angle, target pitch angle, target roll angle, and target yaw angle of each attitude corresponding to each trim moment value, the difference between the corresponding pitch angle, roll angle, and yaw angle is processed to obtain the corresponding first angular rate.

[0141] Each first angular rate is limited to obtain a second angular rate. A PID controller processes each second angular rate to obtain attitude torque adjustment parameters, which are then used to generate corresponding attitude torque value commands. The limiting process in this embodiment is based on the same principle as the limiting process in the embodiments described above.

[0142] Figure 10 A schematic diagram of an attitude controller for a self-rotating glide control module provided in an embodiment of the present invention is shown below. Figure 10 As shown, taking pitch attitude channel control as an example, the main process is to calculate the difference between the target pitch attitude command provided by the target control command module / speed control module and the aircraft pitch angle detected during the flight status detection phase, and then perform amplitude limiting processing. Finally, a PID controller is used to obtain the target pitch torque command of the aircraft.

[0143] As one example, after adjusting to the target attitude, the collective distance of the aircraft is reset to zero after landing to facilitate the normal operation of the aircraft.

[0144] The process of adjusting the target attitude provided by the embodiments of the present invention detects the status information such as the altitude, speed and attitude of the aircraft in real time, and reduces the vertical speed by adjusting the propeller through pitch control. When the speed and altitude meet certain conditions, the aircraft attitude is adjusted to the target attitude to complete the aircraft attitude preparation before landing and make up for the shortcomings of the existing air glide handling strategy that cannot be implemented in low speed and stall states, thereby improving flight safety.

[0145] The foregoing has described in detail various embodiments of the flight control method for aircraft. Based on this, the present invention also discloses a flight control device for aircraft corresponding to the above-described method. Figure 11 This is a structural diagram of a flight control device for an aircraft provided in an embodiment of the present invention. Figure 11 As shown, the flight control system of the aircraft includes:

[0146] The acquisition module 13 is used to acquire the current sink rate, forward velocity and flight altitude of the aircraft, and to determine the corresponding lift and attitude trim moment values ​​based on the current sink rate and forward velocity values ​​respectively.

[0147] Processing module 14 is used to superimpose and distribute the lift value and attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft.

[0148] The first adjustment module 15 is used to adjust each collective pitch value to obtain the corresponding vertical velocity value when the flight altitude value meets the first preset condition.

[0149] The second adjustment module 16 is used to adjust the attitude trim torque value to the target torque value of the target attitude for landing when the vertical velocity value, forward velocity value, and flight altitude value after adjusting each collective pitch value meet the second preset condition. The satisfied altitude value of the flight altitude value within the first preset condition is greater than the satisfied altitude value of the flight altitude value after adjusting each collective pitch value within the second preset condition.

[0150] Since the embodiments of the device part correspond to the embodiments described above, please refer to the embodiments described in the method part for the embodiments of the device part, and will not be repeated here.

[0151] For a description of the flight control device for an aircraft provided by the present invention, please refer to the above method embodiments. The present invention will not be described in detail here, but it has the same beneficial effects as the flight control method for the aircraft described above.

[0152] Figure 12 A structural diagram of another flight control device for an aircraft provided in an embodiment of the present invention is shown below. Figure 12 As shown, the device includes:

[0153] Memory 21 is used to store computer programs;

[0154] Processor 22 is used to execute computer programs to implement flight control methods for an aircraft.

[0155] The processor 22 may include one or more processing cores, such as a quad-core processor or an octa-core processor. The processor 22 may be implemented using at least one of the following hardware forms: Digital Signal Processor (DSP), Field-Programmable Gate Array (FPGA), or Programmable Logic Array (PLA). The processor 22 may also include a main processor and a coprocessor. The main processor, also known as the Central Processing Unit (CPU), is used to process data in the wake-up state; the coprocessor is a low-power processor used to process data in the standby state. In some embodiments, the processor 22 may integrate a Graphics Processing Unit (GPU), which is responsible for rendering and drawing the content to be displayed on the screen. In some embodiments, the processor 22 may also include an Artificial Intelligence (AI) processor, which handles computational operations related to machine learning.

[0156] The memory 21 may include one or more computer-readable storage media, which may be non-transitory. The memory 21 may also include high-speed random access memory and non-volatile memory, such as one or more disk storage devices or flash memory devices. In this embodiment, the memory 21 is used to store at least the following computer program 211, which, after being loaded and executed by the processor 22, is capable of implementing the relevant steps of the flight control method for the aircraft disclosed in any of the foregoing embodiments. In addition, the resources stored in the memory 21 may also include an operating system 212 and data 213, and the storage method may be temporary or permanent storage. The operating system 212 may include Windows, Unix, Linux, etc. The data 213 may include, but is not limited to, data involved in the flight control method of the aircraft.

[0157] In some embodiments, the flight control device of the aircraft may further include a display screen 23, an input / output interface 24, a communication interface 25, a power supply 26, and a communication bus 27.

[0158] Those skilled in the field can understand, Figure 12The structures shown do not constitute a limitation on the flight control system of an aircraft and may include more or fewer components than those shown.

[0159] The processor 22 implements the flight control method of the aircraft provided in any of the above embodiments by calling the instructions stored in the memory 21.

[0160] For a description of the flight control device for an aircraft provided by the present invention, please refer to the above method embodiments. The present invention will not be described in detail here, but it has the same beneficial effects as the flight control method for the aircraft described above.

[0161] Furthermore, the present invention also provides a computer-readable storage medium storing a computer program, which, when executed by processor 22, implements the steps of the flight control method for the aircraft described above.

[0162] It is understood that if the methods in the above embodiments are implemented as software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and executes all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0163] For an introduction to the computer-readable storage medium provided by the present invention, please refer to the above method embodiments. The present invention will not be described in detail here, but it has the same beneficial effects as the flight control method of the above-described aircraft.

[0164] The foregoing has provided a detailed description of the flight control method, flight control device, and medium for an aircraft provided by the present invention. The various embodiments in the specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the devices disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section. It should be noted that those skilled in the art can make various improvements and modifications to the present invention without departing from its principles, and these improvements and modifications also fall within the protection scope of the claims of the present invention.

[0165] It should also be noted that, in this specification, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

Claims

1. A flight control method for an aircraft, characterized in that, include: The current sink rate, forward velocity, and flight altitude of the aircraft are obtained, and the corresponding lift value is determined based on the current sink rate, and the corresponding attitude trim moment value is determined based on the forward velocity value. The lift value and the attitude trim moment value are superimposed and distributed to obtain the collective pitch value of each propeller of the aircraft. When the flight altitude value meets the first preset condition, adjust each of the collective distance values ​​to obtain the corresponding vertical velocity value; When the vertical velocity value, the forward velocity value, and the flight altitude value after adjusting each of the collective pitch values ​​meet the second preset condition, the attitude trim moment value is adjusted to the target moment value of the target attitude for landing, wherein the satisfied altitude value of the flight altitude value within the first preset condition is greater than the satisfied altitude value of the flight altitude value after adjusting each of the collective pitch values ​​within the second preset condition; The forward velocity value includes the current forward velocity value and the target forward velocity value. Determining the corresponding attitude trim moment value based on the forward velocity value includes: Obtain the current forward acceleration value of the aircraft; The first forward velocity value is obtained by subtracting the current forward velocity value and the target forward velocity value. A second forward speed value is obtained by applying speed limiting processing to the first forward speed value. The target acceleration value is obtained by processing the second forward velocity value using a PID controller. The first acceleration value is obtained by subtracting the current forward acceleration value from the target acceleration value. The first acceleration value is subjected to acceleration limiting processing to obtain the second acceleration value; The attitude trim torque value is obtained by processing the second acceleration value using the arctangent function.

2. The flight control method for an aircraft according to claim 1, characterized in that, Before obtaining the current sink rate, forward velocity, and altitude of the aircraft, the method further includes: Obtain the health status information of the aircraft's power system; When the health status information indicates a fault state, the aircraft enters the autorotation descent state. The aircraft is initialized, and the process proceeds to the step of obtaining the current sink rate, forward velocity, flight altitude, and vertical velocity of the aircraft. The initialization operation includes at least disconnecting the mechanical connection of the power system, reducing the collective pitch of each propeller, and initializing the attitude trim torque.

3. The flight control method for an aircraft according to claim 2, characterized in that, The process of superimposing and distributing the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft includes: The first torque value is obtained by weighting and superimposing the lift value and the attitude trim torque value. The collective pitch value of each propeller is determined based on the correspondence between the first torque value and the allocation matrix.

4. The flight control method for an aircraft according to claim 3, characterized in that, Determining the corresponding lift value based on the current sinking rate includes: Obtain the mapping relationship between subsidence rate and tensile force; The corresponding lift value is determined based on the current sinking rate and the mapping relationship between the sinking rate and the tension.

5. The flight control method for an aircraft according to claim 1, characterized in that, The first preset condition is that the flight altitude of the aircraft is less than or equal to the pull-up deceleration altitude. Adjusting each collective pitch value to obtain the corresponding vertical velocity value includes: Determine whether the flight altitude value is less than or equal to the pull-up deceleration altitude value; If so, then the flight altitude value is determined to satisfy the first preset condition; Based on the total distance values, each of the aforementioned total distance values ​​is adjusted according to the preset total distance value within the single-shot time step; The corresponding vertical velocity value is obtained based on the adjusted total distance.

6. The flight control method for an aircraft according to claim 5, characterized in that, The second preset condition is that the vertical velocity value, the forward velocity value, and the flight altitude value are respectively less than or equal to the corresponding preset vertical velocity value, preset forward velocity value, and preset altitude value, wherein the preset altitude value is less than the pull-up deceleration altitude value, the attitude trim moment includes pitch attitude trim moment, roll attitude trim moment, and yaw attitude trim moment, and the target moment value for adjusting to the target attitude according to the attitude trim moment value includes: Determine whether the vertical velocity value, the forward velocity value, and the flight altitude value are respectively less than or equal to the corresponding preset vertical velocity value, the preset forward velocity value, and the preset altitude value; If so, then the vertical velocity value, the forward velocity value, and the flight altitude value are determined to satisfy the second preset condition; Obtain the attitude torque command corresponding to the target attitude, wherein the attitude torque command includes instructions for attitude torque adjustment parameters; Adjust the attitude trimming torque value to the target torque value according to the attitude torque command; Correspondingly, the process of acquiring the attitude moment command specifically includes: acquiring the current pitch angle, current roll angle, current yaw angle, target pitch angle, target roll angle, and target yaw angle corresponding to each trim moment value; The first angular rate is obtained by subtracting the current pitch angle from the target pitch angle, the current roll angle from the target roll angle, the current yaw angle from the target yaw angle, and the current yaw angle from the target yaw angle. Each of the first angular velocities is subjected to angular rate limiting processing to obtain the corresponding second angular rate; The attitude torque adjustment parameters are obtained by processing each of the second angular velocities using a PID controller. The attitude torque adjustment parameters are used to generate the corresponding attitude torque command.

7. The flight control method for an aircraft according to claim 4, characterized in that, Before the step of superimposing and distributing the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft, and after the step of determining the corresponding lift value and attitude trim moment value based on the current sink rate and the forward velocity value, the method further includes: The attitude trim moment value is subjected to amplitude limiting processing to obtain the processed attitude moment value, and then proceeds to the step of superimposing and distributing the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft.

8. A flight control device for an aircraft, characterized in that, include: The acquisition module is used to acquire the current sink rate, forward velocity value and flight altitude value of the aircraft, and determine the corresponding lift value based on the current sink rate, and determine the corresponding attitude trim moment value based on the forward velocity value; The processing module is used to superimpose and distribute the lift value and the attitude trim moment value to obtain the collective pitch value of each propeller of the aircraft; The first adjustment module is used to adjust each of the collective distance values ​​to obtain the corresponding vertical velocity value when the flight altitude value meets the first preset condition. The second adjustment module is used to adjust the attitude trim torque value to the target torque value of the target attitude for landing when the vertical velocity value, the forward velocity value, and the flight altitude value after adjusting each of the collective distance values ​​meet the second preset condition. The altitude value of the flight altitude value within the first preset condition is greater than the altitude value of the flight altitude value after adjusting each of the collective distance values ​​within the second preset condition. The forward velocity value includes the current forward velocity value and the target forward velocity value. Determining the corresponding attitude trim moment value based on the forward velocity value includes: Obtain the current forward acceleration value of the aircraft; The first forward velocity value is obtained by subtracting the current forward velocity value and the target forward velocity value. A second forward speed value is obtained by applying speed limiting processing to the first forward speed value. The target acceleration value is obtained by processing the second forward velocity value using a PID controller. The first acceleration value is obtained by subtracting the current forward acceleration value from the target acceleration value. The first acceleration value is subjected to acceleration limiting processing to obtain the second acceleration value; The attitude trim torque value is obtained by processing the second acceleration value using the arctangent function.

9. A flight control device for an aircraft, characterized in that, include: Memory, used to store computer programs; A processor for executing the computer program to implement the steps of the flight control method for an aircraft 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 that, when executed by a processor, implements the steps of the flight control method for an aircraft as described in any one of claims 1 to 7.

Images