An aircraft landing method, apparatus and aircraft

Abstract

The application relates to an aircraft landing method, device and aircraft. The method comprises the following steps: in response to an aircraft landing request, controlling the aircraft to enter a preset height-keeping mode and hover; acquiring, by a distance measuring module arranged on the aircraft, landing distances of the aircraft body in different directions from a target landing surface when the aircraft is in the hovering state; calculating an inclination angle of the target landing surface according to the acquired landing distances; in the case that the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle, controlling the aircraft to keep the height-keeping mode and triggering a blade-ground-touching risk alarm; the first inclination angle is a critical inclination of the aircraft blade when the aircraft lands on an inclined surface. The method can solve the problem that the aircraft may roll over during landing in the related art.

Description

Technical Field

[0001] The present application relates to the field of aircraft technology, and in particular to an aircraft landing method, device, and aircraft. Background Art

[0002] With the gradual advancement of aircraft technology, aircraft are widely used in various fields, including aerial photography, surveillance, search and rescue, security, resource exploration, and agriculture. Aircraft can replace humans in difficult tasks, traverse complex terrain, shorten operation time, and reduce labor costs. However, this has led to a surge in aircraft accidents, including frequent propeller strikes during landing and rollovers caused by tilting landing surfaces.

[0003] To address the frequent occurrence of aircraft landing accidents, existing technology involves attempting a landing attempt, lowering the aircraft until one side of the landing gear touches the ground, adjusting the fuselage's tilt angle, and determining whether the tilt is suitable for landing. This method cannot complete the landing in one attempt and may trigger multiple go-arounds. Furthermore, if the landing surface's tilt angle is too steep, there is still the risk of the propeller blades contacting the ground before the landing gear, causing a rollover.

[0004] With regard to the problem in related technologies that an aircraft may roll over during landing, no effective solution has been proposed so far. Summary of the Invention

[0005] Based on this, it is necessary to provide an aircraft landing method, device and aircraft to address the above technical issues, so as to solve the problem of possible rollover during the landing process of the aircraft in the related technology.

[0006] In a first aspect, the present application provides a method for landing an aircraft. The method comprises:

[0007] In response to a landing request from the aircraft, controlling the aircraft to enter a preset altitude hold mode and perform hovering;

[0008] Obtaining, by means of a ranging module provided on the aircraft, landing distances from different orientations of the aircraft fuselage to a target landing surface when the aircraft is in a hovering state;

[0009] Calculating the inclination angle of the target landing surface according to the acquired landing distance;

[0010] When the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle, the aircraft is controlled to maintain the altitude hold mode and a blade touchdown risk alarm is triggered; the first inclination angle is the critical inclination of the aircraft's blades touching the ground when the aircraft lands on the inclined surface.

[0011] In one embodiment, the method further comprises:

[0012] When the inclination angle of the target landing surface is less than the preset first inclination angle and greater than or equal to the second inclination angle, the aircraft is controlled to maintain the fixed-altitude mode and a landing slip risk alarm is triggered; the second inclination angle is the critical sliding slope of the aircraft landing on a preset material; the second inclination angle is less than the first inclination angle.

[0013] In one embodiment, the method further comprises:

[0014] When the inclination angle of the target landing surface is less than the second inclination angle, controlling the aircraft to spin in the altitude hold mode until it faces the target landing surface and performs hovering;

[0015] After the aircraft rotates to hover facing the target landing surface, the landing undercarriage of the aircraft is adjusted so that the landing undercarriage of the aircraft is parallel to the target landing surface before landing.

[0016] In one embodiment, the method further comprises:

[0017] When the inclination angle of the target landing surface is less than the preset first inclination angle, acquiring material information of the target landing surface;

[0018] The second inclination angle is determined according to the acquired material information of the target landing surface.

[0019] In one embodiment, obtaining the material information of the target landing surface includes:

[0020] Acquiring image information of the target landing surface, and determining material information of the target landing surface based on the image information;

[0021] Or, receive the material information of the target landing surface sent by the control terminal.

[0022] In one embodiment, determining the second inclination angle according to the acquired material information of the target landing surface includes:

[0023] The acquired material information of the target landing surface is matched with a preset landing surface material information library, and the critical sliding slope of the preset material that matches the target landing surface is determined as the second inclination angle; the landing surface material information library stores a plurality of different preset materials and the critical sliding slopes of the aircraft landing on each of the different preset materials.

[0024] In a second aspect, the present application further provides an aircraft, comprising a fuselage and a controller:

[0025] A plurality of ranging modules are provided below the fuselage, and the plurality of ranging modules are respectively located at different positions of the fuselage;

[0026] The controller includes a memory and a processor, the memory stores a computer program, and the processor implements the steps of the method described in the first aspect when executing the computer program.

[0027] In one embodiment, the aircraft further includes an electric push rod;

[0028] The electric push rod is used to push the rear crossbeam of the tripod to slide along the sliding groove.

[0029] In a third aspect, the present application further provides an aircraft landing device, comprising:

[0030] a response module, configured to control the aircraft to enter a preset altitude hold mode and perform hovering in response to a landing request of the aircraft;

[0031] a ranging module, configured to obtain, through the ranging module provided on the aircraft, a landing distance from a target landing surface to the aircraft fuselage at different orientations when the aircraft is in a hovering state;

[0032] a calculation module, configured to calculate the inclination angle of the target landing surface according to the acquired landing distance;

[0033] and an alarm module, configured to control the aircraft to maintain the altitude hold mode and trigger a blade touchdown risk alarm when the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle; the first inclination angle being the critical inclination of the aircraft's blades touching the ground when the aircraft lands on the inclined surface.

[0034] Compared to related technologies, the aircraft landing method, device, and aircraft provided in this application first respond to an aircraft landing request by controlling the aircraft to enter a preset altitude hold mode and hover. After hovering, the ranging module uses the aircraft's fuselage to obtain the landing distance from the target landing surface at different orientations. The inclination angle of the target landing surface is then calculated based on the measured landing distance. Finally, if the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle, the aircraft is controlled to maintain the altitude hold mode and a blade touchdown risk alarm is triggered. The first inclination angle is the critical inclination angle at which the aircraft's blades touch the ground when landing on an inclined surface. It uses the ranging module to test the landing distance of the aircraft from the target landing surface in different directions in the hovering state to calculate the inclination angle of the target landing surface. When the inclination angle of the target landing surface exceeds the critical inclination of the aircraft's blades touching the ground when the aircraft lands on the inclination surface, the aircraft is controlled to maintain the fixed altitude mode and trigger the blade touchdown risk alarm, thereby avoiding the rollover problem caused by touching the ground on one side of the tripod and judging whether the inclination angle of the fuselage is suitable for landing. It can effectively prevent the aircraft from rolling over due to the blades touching the ground when landing.

[0035] The details of one or more embodiments of the present application are set forth in the following drawings and description to make other features, objects, and advantages of the present application more readily apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0037] Figure 1 A schematic diagram of a portion of the structure of a drone provided in one embodiment of the present application;

[0038] Figure 2 A flowchart of an aircraft landing method provided in one embodiment of the present application;

[0039] Figure 3 A flowchart of an aircraft landing method provided in a preferred embodiment of the present application;

[0040] Figure 4 A schematic diagram of the principle of calculating the inclination angle of a landing surface provided in one embodiment of the present application;

[0041] Figure 5 A structural block diagram of an aircraft landing device provided in one embodiment of the present application;

[0042] Figure 6 A schematic diagram of an aircraft structure provided in one embodiment of the present application;

[0043] Figure 7AThis is a schematic diagram of the structure of the electric push rod provided in one embodiment of the present application before pushing the rear crossbeam of the tripod to slide along the slide groove;

[0044] Figure 7B This is a schematic diagram of the structure after the electric push rod provided in one embodiment of the present application pushes the rear crossbeam of the tripod to slide along the slide groove. DETAILED DESCRIPTION

[0045] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0046] Unless otherwise defined, the technical terms or scientific terms involved in this application should have the general meaning understood by people with ordinary skills in the technical field to which this application belongs. The words "one", "an", "a", "the", "these" and the like in this application do not indicate quantitative restrictions, and they can be singular or plural. The terms "include", "comprise", "have" and any variants thereof involved in this application are intended to cover non-exclusive inclusions; for example, a process, method and system, product or device comprising a series of steps or modules (units) is not limited to the listed steps or modules (units), but may include unlisted steps or modules (units), or may include other steps or modules (units) inherent to these processes, methods, products or devices. The words "connect", "connected", "coupled" and the like involved in this application are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The "plurality" involved in this application refers to two or more. "And / or" describes the relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can represent: A exists alone, A and B exist simultaneously, and B exists alone. Generally, the character " / " indicates that the related objects are in an "or" relationship. The terms "first," "second," "third," etc. used in this application are only used to distinguish similar objects and do not represent a specific ordering of the objects.

[0047] The method embodiment provided in this embodiment can be executed on different aircraft. For example, it can be executed on a drone. Figure 1 FIG. 1 is a schematic diagram of a partial structure of the drone provided in this embodiment. Figure 1 As shown, the drone may include a fuselage 102 (not shown in its entirety) and one or more controllers (not shown), the controller may include one or more processors and a memory for storing data. The drone may also include a transmission device for communication functions. Figure 1 Only one distance measuring module 104 is shown. Figure 1The structure shown is only for illustration and does not limit the structure of the above-mentioned drone. Figure 1 More or fewer components than shown, or with Figure 1 Different configurations shown.

[0048] Specifically, the ranging module 104 is used to measure the landing distance between each test point where the ranging module 104 is installed and the target landing surface. The memory can be used to store computer programs and data, for example, application software programs and modules, such as the computer program corresponding to the drone landing method in this embodiment. The processor executes the computer program stored in the memory to perform various functional applications and data processing, thereby implementing the aforementioned method. The memory can include high-speed random access memory and non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory.

[0049] The transmission device is used to receive or send data via a network. The above network includes a wireless network provided by the control terminal. In one embodiment, the transmission device can be a radio frequency (RF) module, which is used to communicate with the control terminal via wireless means.

[0050] In this embodiment, a method for landing an aircraft is provided. Figure 2 is a flow chart of the aircraft landing method of this embodiment, such as Figure 2 As shown, the process includes the following steps:

[0051] Step S210 , in response to the aircraft landing request, controlling the aircraft to enter a preset altitude hold mode and perform hovering.

[0052] The aircraft landing request herein may be a landing request command received from a mobile terminal, or it may be a landing request command automatically generated by a power detection module in the controller detecting low battery or an overheated temperature. Upon receiving the landing request command, the aircraft controller controls the aircraft to enter a preset fixed-altitude mode for hovering. Specifically, upon receiving the landing request command, the aircraft may be controlled to fly directly above the target landing surface and then enter a preset fixed-altitude mode for hovering. Fixed-altitude mode means the aircraft hovers at a fixed altitude. This fixed altitude can be set within a range of 5 to 10 meters. For example, the fixed altitude in fixed-altitude mode is 5 meters. This fixed altitude ensures safe landing and takeoff of the aircraft and also ensures that the ranging module in the aircraft can accurately measure the landing distance from the test point to the target landing surface. For aircraft equipped with a video capture module, this altitude also ensures that the image capture module can capture image information of the target landing surface. Generally speaking, the altitude setting of this altitude hold mode can be a preset value stored in the controller, or a setting value sent by the user to the aircraft controller via a mobile terminal.

[0053] Step S220: Obtain the landing distances from the target landing surface to the aircraft at different positions of the aircraft body when the aircraft is in a hovering state through a distance measurement module provided on the aircraft.

[0054] After the aircraft enters a preset fixed-altitude mode and maintains a horizontal hover, in this step, ranging modules located at different locations on the lower end of the aircraft measure the landing distance from the target landing surface to the ranging point where each ranging module is located. It should be noted that these ranging modules can be installed at different locations on the lower end of the aircraft, as long as they can detect the distance from each location on the lower end of the aircraft to the target landing surface. For example, the ranging modules can be installed below the aircraft wall or below the aircraft fuselage. There should be at least three ranging modules, installed at different locations, to ensure that the distance from several ranging points on the lower end of the aircraft to the target landing surface can be detected. The more ranging modules are installed, the more landing distance data from different locations can be obtained, and the more accurately the target landing surface inclination angle can be calculated. Furthermore, the ranging modules here can be one or more of infrared ranging using a time-of-flight sensor, ultrasonic ranging using an ultrasonic sensor, and laser ranging using a lidar sensor. The purpose is to accurately measure the landing distance from the test point where the ranging module is installed to the target landing surface while the aircraft is hovering horizontally at a preset fixed altitude. As mentioned above, in general, this landing distance is between 5 meters and 10 meters.

[0055] Step S230: Calculate the inclination angle of the target landing surface based on the acquired landing distance.

[0056] Since the ranging module is installed on the aircraft, the landing distance of the lower end of the aircraft fuselage from the target landing surface at different directions when the aircraft is in a hovering state measured by the ranging module can be used to calculate the inclination angle of the target landing surface. Specifically, the ranging modules can be installed on the same horizontal plane, and a spatial rectangular coordinate system is established through the ranging points where each ranging module is located. Based on the coordinates of each ranging point, the equation of the plane formed by each ranging point is obtained, that is, the equation of the plane passing through each test point. Based on each test point and the distance from each test point to the target landing surface, the equation of the target landing surface is calculated. According to the equation of the plane passing through each test point and the equation of the target landing surface, the angle formed by the two planes is obtained, and this angle is the inclination angle of the target landing surface.

[0057] Preferably, an angle library can be pre-generated, storing the correspondence between the numerical differences in landing distances measured by the ranging modules at different test points and the different landing surface inclination angles, and stored in the fuselage controller's memory. By obtaining the landing distances measured by the ranging modules at each ranging point, the numerical differences in the landing distances at each ranging point are calculated. Based on these numerical differences in the landing distances at each ranging point, the corresponding landing surface inclination angles, i.e., the target landing surface inclination angle, are retrieved from the angle library. Using this angle library storage method, only the numerical values ​​of the landing distances measured by each ranging module need to be calculated, and the target landing surface inclination angle can be obtained through a query. This simplifies algorithm design, reduces the probability of errors in the target landing surface inclination angle calculation, and effectively prevents aircraft rollovers caused by inaccurate target landing surface inclination angle calculations due to algorithm errors.

[0058] In addition, when the landing distances measured by the ranging modules at each ranging point are equal, the controller determines that the target landing surface is a plane, controls the blade speed to slow down, and controls the aircraft to land on the target landing surface.

[0059] Step S240: When the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle, the aircraft is controlled to maintain a constant altitude mode and a blade touchdown risk alarm is triggered; the first inclination angle is the critical inclination of the aircraft's blades touching the ground when the aircraft lands on the inclined surface.

[0060] In this step, since the blade length and blade position of the aircraft are fixed, and the length of the aircraft's footrest beam is also fixed, the critical inclination of the aircraft's blades touching the ground can be calculated based on the length and position data, and this critical inclination is used as the preset first inclination angle and stored in the controller's memory. After obtaining the inclination angle of the target landing surface, the inclination angle of the target landing surface is compared with the first inclination angle preset in the memory. If the inclination angle of the target landing surface is greater than or equal to the preset first inclination angle, it is determined that there is a risk of blades touching the ground on the target landing surface and landing is impossible. When it is determined that there is a risk of blades touching the ground on the target landing surface, the aircraft is controlled to maintain a fixed altitude mode and a blade touching the ground risk alarm is triggered. The blade touching the ground risk alarm can be one or more of the following: the aircraft controller sends a blade touching the ground risk alarm signal to the mobile terminal, the aircraft emits an alarm sound of "blade touching the ground risk", and the alarm light flashes.

[0061] In steps S210 to S240, the aircraft is controlled to enter a preset altitude hold mode and hover in response to a landing request. After hovering, the distance from the aircraft fuselage to the target landing surface at different orientations is obtained through the ranging module. Furthermore, the acquired landing distance is used to calculate the inclination angle of the target landing surface. Finally, based on the calculated inclination angle of the target landing surface, a determination is made as to whether there is a risk of blade contact with the target landing surface. If there is a risk of blade contact with the target landing surface, the aircraft is controlled to maintain the altitude hold mode and a blade contact risk alarm is triggered. This avoids the risk of rollover caused by the aircraft landing on one side of the tripod and determining whether the fuselage inclination angle is suitable for landing. This effectively prevents the aircraft from rolling over due to blade contact during landing, significantly improving the aircraft's flight and landing safety.

[0062] In addition, in another embodiment, the aircraft landing method provided by the present application may further include the following steps based on the above embodiment:

[0063] Step S250: When the inclination angle of the target landing surface is less than a preset first inclination angle and greater than or equal to a preset second inclination angle, the aircraft is controlled to maintain a constant altitude mode and a landing slip risk alarm is triggered; the second inclination angle is the critical sliding slope of the aircraft landing on the preset material; the second inclination angle is less than the first inclination angle.

[0064] As described above, if the target landing surface's inclination angle is less than the preset first inclination angle, that is, if the target landing surface's inclination angle is less than the critical inclination of the aircraft's landing surface, the aircraft can be guaranteed not to have its blades touch the ground and roll over due to excessive inclination of the target landing surface. However, on some relatively smooth landing surfaces, the aircraft still faces the risk of slipping and rolling over.

[0065] Based on this, the aircraft landing method provided in this embodiment further introduces the decision of landing the aircraft at the critical sliding slope of the preset material, i.e., the second inclination angle, when the inclination angle of the target landing surface is less than the preset first inclination angle. Specifically, when the inclination angle of the target landing surface is less than the preset first inclination angle, but exceeds the critical sliding slope of the target landing surface, it is determined that the target landing surface is not suitable for landing, and the aircraft is at risk of sliding on the ground and causing rollover. The aircraft is controlled to maintain a fixed altitude mode, and a landing slip risk alarm is triggered, thereby preventing the aircraft from rolling over due to slipping. When the landing slip risk alarm is triggered, it may be one or more of the following: the aircraft controller sends a landing slip risk alarm signal to the mobile terminal, the aircraft emits an alarm sound of "landing slip risk", and the alarm light flashes.

[0066] Step S260, when the inclination angle of the target landing surface is less than the second inclination angle, control the aircraft to spin in the fixed altitude mode to face the target landing surface and hover; after the aircraft spins to face the target landing surface and hovers, adjust the landing gear of the aircraft so that the landing gear of the aircraft is parallel to the target landing surface and then land.

[0067] Specifically, when it is determined that the inclination angle of the target landing surface is less than the second inclination angle, it can be concluded that the aircraft is landing on the target landing surface at this time, and the blades will not touch the ground, and the aircraft will not slip when landing on the target landing surface. At this time, the controller determines that the target landing surface is suitable for landing. When the controller determines that the target landing surface is suitable for landing, the controller controls the aircraft to spin in the fixed altitude mode. When the nose of the aircraft is facing the target landing surface, the spin is stopped and the horizontal hovering state is maintained. As an implementable method, the aircraft spins until the nose is facing the target landing surface, and then the controller controls the electric push rod of the tripod to push the rear crossbeam of the tripod to move a corresponding displacement, so that the landing tripod can be parallel to the target landing surface, thereby ensuring that the nose of the aircraft is located at the higher end of the target landing surface after landing, and preventing the center of gravity from shifting and causing the aircraft to overturn. Whether the aircraft's nose is facing the target landing surface can be determined by controlling a distance measurement module via a controller to continuously measure the landing distance from a test point to the target landing surface during the autorotation. The difference between the landing distances from each landing point to the target landing surface measured by the distance measurement module and a pre-stored difference when the aircraft's nose is facing the target landing surface is then used to determine whether the aircraft's nose is facing the target landing surface. Alternatively, the aircraft's nose is located at a point in the plane formed by the distance measurement points, and a perpendicular line passing through this point and perpendicular to the intersection of the plane passing through each distance measurement point and the target landing surface is determined. The angle formed by the line passing through the aircraft's nose and tail and this perpendicular line, or the supplementary angle of this angle, is used as the required rotation angle for the aircraft to rotate until it faces the target landing surface. If the aircraft spins to the angle indicated above, it determines whether the landing distance measured by the ranging module at the nose of the aircraft is less than the landing distance measured by the ranging module at the tail. If so, the aircraft stops spinning. If so, it continues spinning to the complementary angle of the angle indicated above, stopping the spin. At this point, the aircraft's nose is facing the target landing surface. The aircraft then adjusts the landing undercarriage based on the calculated inclination angle of the target landing surface, ensuring that it is parallel to the target landing surface. Finally, the controller reduces the propeller speed, allowing the aircraft to land on the target landing surface.

[0068] This landing method adjusts the landing pattern based on the target landing surface's inclination, ensuring the aircraft lands on the target surface without blade contact or slipping. Furthermore, by rotating the aircraft directly toward the target landing surface before landing, it effectively prevents rollovers during landing, effectively resolving the potential for rollovers.

[0069] In addition, in one embodiment, the above-mentioned aircraft landing method may further include the following steps:

[0070] Step S270: When the inclination angle of the target landing surface is less than the preset first inclination angle, obtain material information of the target landing surface; and determine a second inclination angle based on the obtained material information of the target landing surface.

[0071] Specifically, a landing surface material information library can be stored in the aircraft's memory. This library contains information about different preset landing surface materials and the maximum landing surface angle at which the friction generated by the landing undercarriage's anti-slip sleeve on landing surfaces of different preset materials remains stationary, i.e., the critical sliding inclination of the aircraft's landing undercarriage on landing surfaces of different preset materials. If the target landing surface's inclination angle is less than a preset first inclination angle, the controller determines the critical sliding inclination corresponding to this material information, i.e., the second inclination angle, based on the acquired target landing surface material information. The controller then determines whether the aircraft can land safely based on the difference between the target landing surface's inclination angle and the second inclination angle. In this step, by acquiring the target landing surface material information, it is determined whether there is a risk of the aircraft slipping when landing on the target landing surface, thereby further preventing the aircraft from rolling over due to slipping during landing.

[0072] Specifically, in one embodiment, the above step S270 of obtaining the material information of the target landing surface includes the following steps:

[0073] Step S271, obtaining image information of the target landing surface, and determining material information of the target landing surface based on the image information; or, receiving material information of the target landing surface sent by the control terminal.

[0074] In this step, an image recognition module can be installed at the lower end of the aircraft, and image information of landing surfaces of different preset materials can be stored in the aircraft's memory. The image recognition module collects image information of the target landing surface, compares the collected image information of the target landing surface with the image information of landing surfaces of different preset materials stored in the memory, sets a threshold for the comparison similarity, and when the comparison similarity exceeds the set threshold, determines that the material of the target landing surface is the preset material corresponding to the compared image. Alternatively, the user can select the material they observe using a material selection key in the control terminal and send it to the aircraft's controller, or the user can input the material information of the target landing surface based on the material they observe using an input device in the control terminal, and send this material information to the aircraft's controller. The aircraft's controller then determines the material of the target landing surface based on the received material information.

[0075] Furthermore, in one embodiment, the above step S270, determining the second tilt angle according to the acquired material information of the target landing surface, includes the following steps:

[0076] In step S272, the acquired material information of the target landing surface is matched with a preset landing surface material information library, and the critical sliding slope of the matching preset material is determined as the second inclination angle; the landing surface material information library stores a plurality of different preset materials and the critical sliding slopes for the aircraft to land on each of the different preset materials.

[0077] As an implementable embodiment, a preset landing surface material information library can be stored in the memory of the aircraft controller. When the controller obtains the material information of the target landing surface, the material information of the target landing surface is matched with the preset landing surface material information library to obtain a matching preset material, and the sliding critical slope of the matched preset material is used as the second inclination angle to judge the size of the inclination angle of the target landing surface and the second inclination angle. Based on the judgment result, it is determined whether the target landing surface is suitable for landing at this time.

[0078] The present application is described and illustrated below through preferred embodiments.

[0079] Figure 3 This is a flow chart of the aircraft landing method provided by the preferred embodiment of this application. Figure 3 As shown, the aircraft landing method includes the following steps:

[0080] Step S301: In response to a landing request of an aircraft, the aircraft is controlled to enter a preset altitude-holding mode and to hover.

[0081] Among them, the preset fixed altitude mode can be set through the control terminal according to actual conditions. Its purpose is to ensure that this fixed altitude can ensure the safe landing and take-off of the aircraft, and also ensure that the ranging module in the aircraft can accurately measure the landing distance from the test point to the target landing surface, and also ensure that the image acquisition module can collect the material information of the target landing surface.

[0082] Step S302: Obtain the landing distances from the target landing surface to the aircraft at different positions of the aircraft body when the aircraft is in a hovering state through a distance measurement module provided on the aircraft.

[0083] Step S303, determining whether the landing distances from the target landing surface to the aircraft body at different orientations are equal when the aircraft is in a hovering state; if the landing distances from the target landing surface to the aircraft body at different orientations are equal when the aircraft is in a hovering state, executing step S311; if the landing distances from the target landing surface to the aircraft body at different orientations are not equal when the aircraft is in a hovering state, executing step S304.

[0084] In this step, if the measured landing distances from the target landing surface at different orientations of the aircraft while the aircraft is in a hovering state are equal, the target landing surface can be determined to be horizontal. If the target landing surface is horizontal, the controller adjusts the aircraft's blade speed to land.

[0085] Step S304: Calculate the inclination angle of the target landing surface based on the acquired landing distance.

[0086] Step S305 , determining whether the inclination angle of the target landing surface is less than the critical inclination of the aircraft blades touching the ground; if so, executing step S306 ; if not, executing step S309 .

[0087] Alternatively, if the target landing surface's inclination angle is less than the critical sliding slope for the aircraft's blades to touch the ground, the aircraft's memory may store the critical sliding slopes of various preset landing surface materials. Based on the magnitude of the target landing surface's inclination angle at that moment and the critical sliding slopes of the preset landing surface materials stored in the memory, the available landing surface material is determined, and the available landing surface material information is transmitted to the control terminal. For example, the memory may store the critical sliding slope for the aircraft landing on grass as C1, the critical sliding slope for the aircraft landing on asphalt as C2, and the critical sliding slope for the aircraft landing on cement road as C3, where C1 > C2 > C3. The target landing surface's inclination angle at that moment is denoted as D, and the magnitude of D relative to C1, C2, and C3 is determined. When D>C1, none of the landing materials pre-stored in the aircraft meets the landing conditions. In this case, step S309 is executed; when C1>D>C2, the information "the material of the landing surface is lawn" is sent to the control terminal. After receiving the landing confirmation command, step S310 is executed; when C2>D>C3, the information "the material of the landing surface is lawn and asphalt road" is sent to the control terminal. After receiving the landing confirmation command, step S310 is executed; when C3>D, the information "the material of the landing surface is lawn, asphalt road, cement road" is sent to the control terminal. After receiving the landing confirmation command, step S310 is executed.

[0088] Step S306: determining the material information of the target landing surface by receiving the material information of the target landing surface sent by the control terminal or by acquiring image information of the target landing surface.

[0089] Step S307: Match the acquired material information of the target landing surface with a preset landing surface material information library, and determine the sliding critical slope of the preset material that matches the target landing surface as the second inclination angle.

[0090] Step S308, determining whether the inclination angle of the target landing surface is less than the second inclination angle; if so, executing step S310; if not, executing step S309.

[0091] Step S309: Control the aircraft to maintain the altitude hold mode and trigger a risk alarm.

[0092] It should be noted that the risk alarm here can trigger different risk alarms according to different situations. When the inclination angle of the target landing surface is greater than or equal to the critical inclination of the aircraft blade touching the ground, the blade touching the ground risk alarm is triggered. When the inclination angle of the target landing surface is greater than or equal to the second inclination angle, the landing slip risk alarm is triggered.

[0093] Step S310: Control the aircraft to spin in the altitude hold mode until it faces the target landing surface and hovers; adjust the landing gear of the aircraft so that the landing gear is parallel to the target landing surface.

[0094] Step S311: adjust the blade speed to control the aircraft to land on the target landing surface.

[0095] It should be noted that the aircraft can be rotated to face the target landing surface in step S302 of this embodiment while the distance measurement module is measuring the distance from each test point to the target landing surface. Figure 4 As shown, Figure 4 This is a schematic diagram of the principle of calculating the inclination angle of the landing surface. It is assumed that three ranging points (i.e., the installation points of the ranging module) are set, test point 420, test point 440, and test point 460. The three ranging points are set below the aircraft wall in different directions. Among them, ranging point 420 and ranging point 440 are symmetrically distributed on both sides of the nose, and test point 460 is located at the tail. The landing distance between ranging point 420 and landing surface 400 measured by the ranging module is L1, the landing distance between ranging point 440 and landing surface 400 measured by the ranging module is L2, and the landing distance between ranging point 460 and landing surface 400 measured by the ranging module is L3. Based on the horizontal hovering state, the controller of the aircraft controls the ranging module to measure the distance, and at the same time, the controller controls the aircraft to spin. When the landing distances measured by the three ranging points meet L3>L1=L2, the aircraft stops spinning, and the aircraft is now facing the landing surface. The distance between the test point 440 and the test point 460 is L4, which can be calculated according to the formula The inclination angle of the landing surface 400 is calculated, where D is the inclination angle of the landing surface 400 .

[0096] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0097] Based on the same inventive concept, this embodiment also provides an aircraft landing device, which is used to implement the above-mentioned embodiments and preferred embodiments. Details already described will not be repeated here. The terms "module," "unit," "subunit," etc. used below may refer to a combination of software and / or hardware that implements a predetermined function. Although the devices described in the following embodiments are preferably implemented in software, implementation using hardware, or a combination of software and hardware, is also possible and contemplated.

[0098] In one embodiment, Figure 5 As shown, an aircraft landing device 50 is provided, comprising:

[0099] The response module 52 is used to control the aircraft to enter a preset altitude holding mode and hover in response to the aircraft landing request;

[0100] The ranging module 54 is used to obtain the landing distance from the aircraft to the target landing surface at different positions of the aircraft body in the hovering state through the ranging module provided on the aircraft;

[0101] A calculation module 56 is used to calculate the inclination angle of the target landing surface based on the acquired landing distance;

[0102] And an alarm module 58 is used to control the aircraft to maintain the altitude hold mode and trigger the blade touchdown risk alarm when the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle; the first inclination angle is the critical inclination of the aircraft's blades touching the ground when the aircraft lands on the slope.

[0103] The aircraft landing device 50 controls the aircraft to enter a preset altitude hold mode in response to a landing request. It then measures the landing distance from the target landing surface at different orientations of the aircraft fuselage while in a hovering state. Based on the landing distance, it calculates the inclination angle of the target landing surface. When the inclination angle of the target landing surface is greater than or equal to the critical pitch of the aircraft's blades contacting the landing slope, the aircraft is controlled to maintain the altitude hold mode and a blade contact risk alarm is triggered. This prevents the aircraft's blades from contacting the ground during landing, effectively preventing rollovers caused by blade contact.

[0104] In some embodiments, the aircraft landing device 50 further includes an image acquisition module. The image acquisition module is used to acquire image information of the target landing surface and determine material information of the target landing surface based on the image information.

[0105] It should be noted that the above modules can be functional modules or program modules, and can be implemented through software or hardware. For modules implemented through hardware, the above modules can be located in the same processor; or the above modules can be located in different processors in any combination.

[0106] Based on the same inventive concept, in one embodiment, Figure 6 As shown, a schematic structural diagram of an aircraft 600 is provided, including a fuselage 620 and a controller (not shown), wherein:

[0107] The fuselage 620 has a plurality of ranging modules 640 disposed below it. The plurality of ranging modules 640 are located at different positions of the fuselage 620.

[0108] The controller includes a storage and a processor; wherein: the storage is used to store computer programs and data; the processor is used to implement the steps of any of the above method embodiments when executing the computer program.

[0109] When the aircraft receives a landing request and enters a preset fixed-altitude hovering mode, the aircraft controller controls the ranging module 640 to test the landing distance of each test point from the target landing surface. After receiving the controller's test command, the ranging module 104 uses one or more of the following methods: infrared ranging using a TOF sensor, ultrasonic ranging using an ultrasonic sensor, and laser ranging using a lidar sensor to measure the landing distance of each test point from the target landing surface. The ranging module 640 can be installed at different locations on the lower end of the aircraft, either below the aircraft fuselage 620 or at different test points below the aircraft wall. In addition, at least three ranging modules 620 are provided. The more ranging modules 640 are provided, the more landing distance data from different locations measured by the ranging module 104 is obtained, and the more accurately the calculated inclination angle of the target landing surface is calculated. The distance measurement module 640 measures the landing distance between each test point and the target landing surface, and then calculates the target landing surface inclination angle based on the landing distance. By comparing the target landing surface inclination angle with the first inclination angle and the second inclination angle pre-stored in the memory, it is determined whether the aircraft will have the risk of blades touching the ground and the risk of sliding back on the ground, thereby avoiding the phenomenon of the aircraft rolling over due to blades touching the ground or sliding back on the ground during landing, and effectively solving the problem of the aircraft rolling over during landing.

[0110] In one embodiment, Figure 6 As shown, a landing footrest 660 and an electric push rod 680 are also provided below the aircraft fuselage 620. The landing footrest 660 comprises a front crossbeam 662 and a rear crossbeam 664. The front crossbeam 662 is connected to the fuselage 620 and can rotate relative to the fuselage 620. The rear crossbeam 664 is slidably connected to the fuselage 620 via a pre-set slide groove and can be extended and retracted relative to the fuselage 620. The electric push rod 680 is used to push the rear crossbeam 664 to slide along the slide groove.

[0111] The front crossbeam 662 and the rear crossbeam 664 of the landing leg are both perpendicular and fixedly connected to the landing leg 660. The front crossbeam 662 is connected to the fuselage 620 tip and can rotate relative to the fuselage 620 under the force of the rear crossbeam 664. The rear crossbeam 664 is slidably connected to the fuselage 620 via a slide groove and can be extended and retracted relative to the fuselage 620 under the action of the push rod of the electric push rod 680. The push rod of the electric push rod 680 pushes the rear crossbeam of the aircraft to extend and retract, thereby adjusting the angle of the landing leg 660 of the aircraft. By adjusting the landing leg 660 to be parallel to the target landing surface before landing, the safety of the aircraft landing is effectively improved and the probability of the aircraft rolling over during landing is reduced.

[0112] Preferably, the rear crossbeam 664 and the front crossbeam of the tripod can be designed to be slidably connected to the fuselage 620 through a pre-set slide groove, and can be extended and retracted relative to the fuselage 620 by the electric push rod 680 and rotated through the slide groove. By designing that all four crossbeams can be extended and rotated, the purpose of flexible adjustment of the landing tripod 660 is achieved.

[0113] Figure 7A This is a schematic diagram of the structure of the electric push rod provided in one embodiment of the present application before pushing the rear crossbeam of the tripod to slide along the slide groove; Figure 7B This is a schematic diagram of the structure after the electric push rod provided in one embodiment of the present application pushes the rear crossbeam of the tripod to slide along the slide groove.

[0114] like Figure 7A and Figure 7B As shown, the electric push rod 680 pushes the rear cross beam 664 of the landing stand so that the landing stand 660 is parallel to the target landing surface.

[0115] Specifically, the electric push rod 680 includes a motor and a push rod, and is controlled by a controller. In this embodiment, the electric push rod 680 can be a worm gear transmission or a gear transmission. Based on control commands from the controller, the motor controls the movement of the push rod. As a feasible embodiment, the controller can query the required displacement of the rear cross beam 664 based on the calculated inclination angle of the target landing surface, using a pre-stored correspondence between different angles and displacements in memory. Based on this required displacement, the controller controls the push rod using the motor, causing the push rod to slide the rear cross beam 664 along the chute by a corresponding displacement. In this manner, the landing leg 660 of the aircraft is aligned with the target landing surface. As another feasible embodiment, the motor can drive the push rod to move at a constant speed under the control of the controller. Based on the calculated inclination angle of the target landing surface, the controller can query the time required for the motor to push the push rod to achieve the corresponding angle, using a pre-stored correspondence between different angles and the time it takes for the motor to push the push rod. The controller then uses the motor to move the push rod for the length of the query to achieve the alignment. By adjusting the landing footrest 660 to be parallel to the target landing surface, the safety of the aircraft landing is effectively improved and the probability of the aircraft rolling over during landing is reduced.

[0116] Preferably, the landing undercarriage 660 below the aircraft is equipped with an anti-skid cover that generates friction with the landing surface, preventing the aircraft from sliding backwards. The friction generated by the anti-skid cover on landing surfaces of different materials maintains the maximum landing angle at which the aircraft lands on the target landing surface, i.e., the critical sliding slope of the landing undercarriage 660 on landing surfaces of different materials.

[0117] It should be understood that the specific embodiments described herein are only used to explain this application and are not used to limit it. Based on the embodiments provided in this application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0118] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties.

[0119] Obviously, the accompanying drawings are merely examples or embodiments of the present application. A person skilled in the art can also apply the present application to other similar situations based on these drawings without inventive effort. Furthermore, it is understandable that, although the work involved in this development process may be complex and lengthy, certain design, manufacturing, or production changes based on the technical content disclosed in this application are merely routine technical means for a person skilled in the art and should not be considered to constitute a deficiency in the disclosure of the present application.

[0120] The term "embodiment" as used in this application refers to specific features, structures, or characteristics described in conjunction with the embodiment that can be included in at least one embodiment of this application. The appearance of this phrase in various places in the specification does not necessarily mean that the embodiment is the same, nor does it mean that it is mutually exclusive with other embodiments and is independent or optional. It is understood, either explicitly or implicitly, by those skilled in the art that the embodiments described in this application can be combined with other embodiments when there is no conflict.

[0121] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of patent protection. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for landing an aircraft, characterized in that: The method comprises: In response to a landing request from the aircraft, controlling the aircraft to enter a preset altitude hold mode and perform hovering; Obtaining, by means of a ranging module provided on the aircraft, landing distances from different orientations of the aircraft fuselage to a target landing surface when the aircraft is in a hovering state; Calculating the inclination angle of the target landing surface according to the acquired landing distance; When the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle, controlling the aircraft to maintain the altitude hold mode and triggering a blade touchdown risk alarm; the first inclination angle is a critical inclination angle for the aircraft's blades to touchdown when the aircraft lands on an inclined surface; When the inclination angle of the target landing surface is less than the preset first inclination angle, obtaining material information of the target landing surface; determining a second inclination angle based on the obtained material information of the target landing surface; the second inclination angle being a critical sliding slope for the aircraft to land on the preset material; the second inclination angle being less than the first inclination angle; When the inclination angle of the target landing surface is smaller than the second inclination angle, the aircraft is controlled to land.

2. The aircraft landing method according to claim 1, characterized in that: The method further comprises: When the inclination angle of the target landing surface is less than the preset first inclination angle and greater than or equal to the second inclination angle, the aircraft is controlled to maintain the altitude-holding mode and a landing slip risk alarm is triggered.

3. The aircraft landing method according to claim 1, characterized in that: When the inclination angle of the target landing surface is less than the second inclination angle, controlling the aircraft to land includes: When the inclination angle of the target landing surface is less than the second inclination angle, controlling the aircraft to spin in the altitude hold mode until it faces the target landing surface and performs hovering; After the aircraft rotates to hover facing the target landing surface, the landing undercarriage of the aircraft is adjusted so that the landing undercarriage of the aircraft is parallel to the target landing surface before landing.

4. The aircraft landing method according to claim 1, characterized in that: The obtaining of material information of the target landing surface includes: Acquiring image information of the target landing surface, and determining material information of the target landing surface based on the image information; Or, receive the material information of the target landing surface sent by the control terminal.

5. The aircraft landing method according to claim 1, characterized in that: The determining the second inclination angle according to the acquired material information of the target landing surface includes: The acquired material information of the target landing surface is matched with a preset landing surface material information library, and the critical sliding slope of the preset material that matches the target landing surface is determined as the second inclination angle; the landing surface material information library stores a plurality of different preset materials and the critical sliding slopes of the aircraft landing on each of the different preset materials.

6. An aircraft comprising a fuselage and a controller, characterized in that: A plurality of ranging modules are provided below the fuselage, and the plurality of ranging modules are respectively located at different positions of the fuselage; The controller includes a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the method according to any one of claims 1 to 5 when executing the computer program.

7. The aircraft according to claim 6, characterized in that A landing tripod is also provided under the fuselage; The landing footrest includes a front crossbeam and a rear crossbeam; The front crossbeam of the tripod is connected to the fuselage tip and can rotate relative to the fuselage; The rear cross beam of the tripod is slidably connected to the fuselage through a preset sliding groove and can be extended and retracted relative to the fuselage.

8. The aircraft according to claim 7, characterized in that Also includes electric actuators; The electric push rod is used to push the rear crossbeam of the tripod to slide along the sliding groove.

9. An aircraft landing device, characterized in that: The device comprises: a response module, configured to control the aircraft to enter a preset altitude hold mode and perform hovering in response to a landing request of the aircraft; a ranging module, configured to obtain, through the ranging module provided on the aircraft, a landing distance from a target landing surface to the aircraft fuselage at different orientations when the aircraft is in a hovering state; a calculation module, configured to calculate the inclination angle of the target landing surface according to the acquired landing distance; And an alarm module, used to control the aircraft to maintain the altitude hold mode and trigger a blade touchdown risk alarm when the inclination angle of the target landing surface is greater than or equal to a preset first inclination angle; the first inclination angle is the critical inclination of the aircraft blades touching the ground when the aircraft lands on the inclination surface; when the inclination angle of the target landing surface is less than the preset first inclination angle, obtain the material information of the target landing surface; determine a second inclination angle based on the acquired material information of the target landing surface; the second inclination angle is the critical sliding inclination of the aircraft landing on the preset material; the second inclination angle is less than the first inclination angle; when the inclination angle of the target landing surface is less than the second inclination angle, control the aircraft to land.

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