Landing obstacle avoidance method for unmanned aerial vehicle, unmanned aerial vehicle and computer-readable storage medium

Abstract

The present application discloses a landing obstacle avoidance method, an unmanned aerial vehicle, and a computer-readable storage medium for the unmanned aerial vehicle. The landing obstacle avoidance method for the unmanned aerial vehicle includes: when the unmanned aerial vehicle is in the level flight stage of landing, determining whether there is an obstacle in the forward flight path; wherein, the height difference between the current flight height of the unmanned aerial vehicle and the height of the obstacle is less than a set height difference; if there is the obstacle in the forward flight path, controlling the unmanned aerial vehicle to increase the flight height to avoid the obstacle. The above solution can ensure that the unmanned aerial vehicle will not collide with an obstacle during landing.

Description

Technical Field

[0001] This application relates to the technical field of unmanned aerial vehicle (UAV) control, and particularly to a landing obstacle avoidance method for a UAV, a UAV, and a computer-readable storage medium. Background Art

[0002] The landing route is the process by which a UAV reduces its altitude and speed until it lands. The current common solution in the industry is as follows: at the end of the mission route, there is a descending spiral point. The route circles at a certain radius at the spiral point while reducing altitude. When the altitude of the aircraft drops to an appropriate value, it breaks away from the spiral and then flies horizontally to the landing point. The disadvantage of the existing solution is that it cannot ensure that the UAV will not collide with obstacles during the landing process. Summary of the Invention

[0003] The main technical problem to be solved by this application is to provide a landing obstacle avoidance method for a UAV, a UAV, and a computer-readable storage medium, which can ensure that the UAV will not collide with obstacles during the landing process.

[0004] To solve the above problems, in the first aspect of this application, a landing obstacle avoidance method for a UAV is provided. The landing obstacle avoidance method for the UAV includes: when the UAV is in the level flight stage of landing, determining whether there is an obstacle in the forward flight path; wherein, the height difference between the current flight height of the UAV and the height of the obstacle is less than a set height difference; if there is the obstacle in the forward flight path, controlling the UAV to increase its flight height to avoid the obstacle.

[0005] Among them, the step of determining whether there is an obstacle in the forward flight path when the UAV is in the level flight stage of landing includes: when the UAV is in the level flight stage of landing, obtaining the terrain heights of a plurality of sampling points within a set distance ahead based on the flight route, and then determining whether there is the obstacle in the forward flight path according to the magnitude relationship between the highest terrain height among the plurality of terrain heights and the difference between the current flight height and the set height difference.

[0006] Among them, the plurality of sampling points are arranged at equal intervals along the flight direction of the UAV.

[0007] Among them, the step of determining whether there is an obstacle in the forward flight path when the UAV is in the level flight stage of landing includes: when the UAV is in the level flight stage of landing, using radar to monitor whether there is an obstacle within a preset range in front of the UAV; the step of controlling the UAV to increase its flight altitude to avoid the obstacle includes: reducing the flight speed of the UAV and increasing the altitude of the UAV until no obstacle is detected within the range of the set altitude difference directly in front of the UAV; among them, the flight speed of the UAV is negatively correlated with the distance between the UAV and the obstacle.

[0008] Among them, after the step of reducing the flight speed of the UAV and increasing the altitude of the UAV until no obstacle is detected within the preset range in front of the UAV, it includes: controlling the UAV to fly level, and after detecting that the UAV has flown over the obstacle, reducing the flight altitude of the UAV to restore to the flight altitude and flight speed before the increase.

[0009] Among them, the step of, if there is an obstacle in the forward flight path, controlling the UAV to increase its flight altitude to avoid the obstacle includes: updating the flight safety altitude of the UAV based on the height of the obstacle and the set altitude difference; determining the climbing slope of the UAV according to the altitude difference between the updated flight safety altitude and the current flight altitude, and the horizontal distance between the UAV and the obstacle; in response to the climbing slope being greater than a preset threshold, controlling the UAV to circle and fly to the updated flight safety altitude; in response to the climbing slope being less than or equal to the preset threshold, controlling the UAV to climb and fly to the updated flight safety altitude.

[0010] Among them, before the step of determining whether there is an obstacle in the forward flight path when the UAV is in the level flight stage of landing, it further includes: receiving the path instruction for the UAV to land; among them, the path instruction at least includes the position information of the descending and circling point of the UAV; obtaining the current position of the UAV, selecting the higher one of the current position and the position information of the descending and circling point as the actual circling point altitude, using the actual circling point altitude as the flight altitude, and using the area corresponding to the descending and circling point as the end point to enter the level flight stage.

[0011] Among them, the step of entering the level flight phase with the actual hovering point height as the flight height and the area corresponding to the descending hovering point as the end point includes: in response to the height of the current position being less than the height in the position information of the descending hovering point, controlling the drone to hover and fly from the current position to the actual hovering point height, and then entering the level flight phase with the actual hovering point height as the flight height and the descending hovering point as the end point; in response to the height of the current position being greater than or equal to the height in the position information of the descending hovering point, controlling the drone to enter the level flight phase with the height of the current position as the flight height and the airspace area corresponding to the descending hovering point as the end point.

[0012] Among them, the position information of the descending hovering point further includes a hovering radius; after the step of entering the level flight phase with the actual hovering point height as the flight height and the area corresponding to the descending hovering point as the end point, it includes: using the actual hovering point height as the starting landing height, controlling the drone to fly to the area corresponding to the descending hovering point, and hovering and landing based on the hovering radius with the vertical line where the descending hovering point is located as the axis.

[0013] Among them, the drone is a vertical takeoff and landing fixed-wing drone, and the path instruction further includes the mode switching height and the position information of the landing point; after the step of entering the level flight phase with the actual hovering point height as the flight height and the area corresponding to the descending hovering point as the end point, it includes: controlling the drone to hover and land to the mode switching height, then flying level to the airspace above the landing point with the mode switching height as the flight height, and vertically landing at the landing point.

[0014] Among them, the step of controlling the drone to hover and land to the mode switching height, then flying level to the airspace above the landing point with the mode switching height as the flight height, and vertically landing at the landing point includes: controlling the drone to hover and land to the mode switching height in the fixed-wing mode, then switching the drone to the rotor mode, flying level to the airspace above the landing point with the mode switching height as the flight height, and then vertically landing at the landing point.

[0015] To solve the above problems, a second aspect of the present application provides a drone, including: a fuselage, a processor, and a memory; the processor and the memory are accommodated inside the fuselage. Among them, the memory stores program instructions, and the processor retrieves the program instructions from the memory to execute the landing obstacle avoidance method of the drone in the first aspect above.

[0016] To solve the above problems, a third aspect of the present application provides a computer-readable storage medium, on which program instructions are stored, and when the program instructions are executed by a processor, the landing obstacle avoidance method of the unmanned aerial vehicle in the first aspect above is implemented.

[0017] The beneficial effects of the present invention are as follows: Different from the prior art, in the landing obstacle avoidance method of the unmanned aerial vehicle of the present application, when the unmanned aerial vehicle is in the level flight stage of landing, it is judged whether there are obstacles in the front flight path. If there are obstacles in the front flight path, the unmanned aerial vehicle is controlled to increase the flight altitude to avoid the obstacles; wherein, the height difference between the current flight altitude of the unmanned aerial vehicle and the height of the obstacle is less than the set height difference. By setting a predetermined height difference, when the unmanned aerial vehicle is in the level flight stage of landing, by detecting the front flight path, if the height difference between the current flight altitude of the unmanned aerial vehicle and the height of the object is less than the set height difference, it is determined that the object is an obstacle, and the actual height obtained by adding the predetermined height difference to the height of the obstacle is used as the flight safety altitude of the unmanned aerial vehicle, which can ensure that the unmanned aerial vehicle will not hit the obstacle during landing. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is a schematic flowchart of the first embodiment of the landing obstacle avoidance method of the unmanned aerial vehicle of the present application;

[0019] Figure 2 is a schematic display diagram of determining an obstacle through terrain data in an application scenario of the present application;

[0020] Figure 3 is Figure 1 a schematic flowchart of an embodiment of step S12 in

[0021] Figure 4 is a schematic display diagram of the process of avoiding an obstacle by hovering and climbing in an application scenario of the present application;

[0022] Figure 5 is a schematic display diagram of the process of avoiding an obstacle by climbing straight in an application scenario of the present application;

[0023] Figure 6 is a schematic flowchart of the second embodiment of the landing obstacle avoidance method of the unmanned aerial vehicle of the present application;

[0024] Figure 7 is a schematic display diagram of determining an obstacle through radar in an application scenario of the present application;

[0025] Figure 8 is a schematic display diagram of the process of avoiding an obstacle through radar in an application scenario of the present application;

[0026] Figure 9 is a schematic flowchart of the third embodiment of the landing obstacle avoidance method of the unmanned aerial vehicle of the present application;

[0027] Figure 10 is Figure 9 A schematic flow chart of an embodiment of step S93;

[0028] Figure 11 A schematic diagram showing the landing route in an application scenario of the present application;

[0029] Figure 12 A schematic diagram showing the landing route in another application scenario of the present application;

[0030] Figure 13 A schematic diagram showing the landing route in yet another application scenario of the present application;

[0031] Figure 14 A schematic flow chart of the fourth embodiment of the landing obstacle avoidance method for the unmanned aerial vehicle of the present application;

[0032] Figure 15 A schematic diagram of the frame structure of an embodiment of the unmanned aerial vehicle of the present application;

[0033] Figure 16 A schematic diagram of the structure of an embodiment of the computer-readable storage medium of the present application. Detailed implementation manners

[0034] The following describes the solutions of the embodiments of the present application in detail with reference to the accompanying drawings of the specification.

[0035] In the following description, specific details such as specific system architectures, interfaces, and technologies are presented for the purpose of illustration rather than limitation, so as to thoroughly understand the present application.

[0036] The terms "system" and "network" are often used interchangeably in this article. The term "and / or" in this article merely describes the association relationship of associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this article generally represents an "or" relationship between the associated objects before and after. In addition, "plurality" in this article means two or more than two.

[0037] Please refer to Figure 1 , Figure 1 A schematic flow chart of the first embodiment of the landing obstacle avoidance method for the unmanned aerial vehicle of the present application. The landing obstacle avoidance method for the unmanned aerial vehicle in this embodiment includes the following steps:

[0038] Step S11: When the unmanned aerial vehicle is in the level flight stage of landing, determine whether there is an obstacle in the front flight path; wherein, the height difference between the current flight height of the unmanned aerial vehicle and the height of the obstacle is less than the set height difference.

[0039] It is understandable that the landing process of the drone includes the process of the drone reducing its flight altitude and speed until it lands. Generally speaking, the landing route of the drone can start from any point at the end of the mission route. The drone reaches the descent and hover point after the level flight phase. The route circles around at a certain radius at the descent and hover point while reducing its altitude. When the altitude of the drone drops to an appropriate value, it breaks away from the hover and flies horizontally towards the landing point, decelerates during the flight towards the landing point, switches to the rotor mode when decelerating to a certain speed value, hovers above the landing point, and finally lands vertically at the landing point. Therefore, when planning the landing route of the drone, it is necessary to detect obstacles on the flight path to avoid hitting obstacles during landing. In particular, since the process of the drone reaching the descent and hover point from the current position through the level flight phase is at a relatively high altitude in the landing route and is prone to hitting obstacles, it is necessary to avoid obstacles on the forward flight path when the drone is in the level flight phase of landing.

[0040] Please combine Figure 2 , Figure 2 FIG. is a schematic diagram showing the determination of obstacles through terrain data in an application scenario of the present application. When the drone is in the level flight phase of landing, it can detect objects on the forward flight path in real time. Generally speaking, when the current flight altitude H1 of the drone is greater than the height H3 of the object, the drone can pass through. However, in actual applications, in order to ensure that the drone does not collide with the object, a safety altitude needs to be set, that is, a set altitude difference H2 is set. In fact, it is necessary that the current flight altitude H1 of the drone is greater than the height H3 of the object plus the set altitude difference H2 to ensure the safe passage of the drone. Therefore, when detecting an object on the forward flight path, after adding the set altitude difference H2 to the height H3 of a certain object, if it is greater than the current flight altitude H1 of the drone, it can be determined that the object is an obstacle relative to the drone, that is, the altitude difference between the current flight altitude H1 of the drone and the height of the obstacle is less than the set altitude difference H2.

[0041] In an embodiment, the above step S11 may include: when the drone is in the level flight phase of landing, obtaining the terrain heights of multiple sampling points within a set distance ahead based on the flight route, and then determining whether there is an obstacle on the forward flight path according to the magnitude relationship between the highest terrain height among the multiple terrain heights and the difference between the current flight altitude and the set altitude difference.

[0042] It can be understood that if the highest terrain height is greater than the difference between the current flight height and the set height difference, that is, the height after adding the set height difference to the highest terrain height is greater than the current flight height of the drone, it can be determined that there is an obstacle in the forward flight path; if the highest terrain height is less than or equal to the difference between the current flight height and the set height difference, that is, the height after adding the set height difference to the highest terrain height is less than or equal to the current flight height of the drone, it can be determined that there is no obstacle in the forward flight path.

[0043] Further, the multiple sampling points are arranged at equal intervals along the flight direction of the drone. Specifically, the interval distance between two adjacent sampling points can be 10 to 100 meters, for example, it can be 50 meters.

[0044] Please continue to combine Figure 2 , in an application scenario, the drone can store terrain data from all over the world, forming a table with equally spaced longitude and latitude. When any longitude and latitude coordinate is input, the terrain height corresponding to this coordinate can be found by looking up the table and interpolation, and the terrain height can be expressed in terms of altitude. Specifically, during the flight of the drone, the terrain avoidance program will continuously check the terrain height of the forward flight path of the drone, collect the terrain heights of 5 points at equal intervals L at a certain distance, and then add the "set height difference H2" set by the user to the terrain heights of these 5 sampling points, and then determine the highest point among the 5 points as the obstacle point, and the height H4 of the obstacle point is the flight safety height. If the flight height of the original flight path is not lower than the height H4 of the obstacle point, it means that there is no obstacle in the forward flight path, and the drone can pass by keeping the original flight path unchanged; if the flight height of the original flight path is lower than the height H4 of the obstacle point, it means that there is an obstacle in the forward flight path, and the drone needs to increase its flight height to pass safely.

[0045] Step S12: If there is an obstacle in the forward flight path, control the drone to increase its flight height to avoid the obstacle.

[0046] It can be understood that if it is determined that there is an obstacle in the forward flight path, that is, the height difference between the current flight height of the drone and the height of the obstacle is less than the set height difference, then it is necessary to control the drone to increase its flight height so that the flight height of the drone is greater than the height after adding the set height difference to the obstacle, so as to enable the drone to avoid the obstacle.

[0047] In the above solution, by setting a predetermined height difference, when the drone is in the level flight stage of landing, by detecting the forward flight path, if the height difference between the current flight height of the drone and the height of the object is less than the set height difference, then the object is determined as an obstacle, and the actual height obtained by adding the predetermined height difference to the height of the obstacle is used as the flight safety height of the drone, which can ensure that the drone will not hit the obstacle during landing.

[0048] Please refer to Figure 3 , Figure 3 which Figure 1 is a schematic flowchart of an embodiment of step S12 in

[0049] Step S121: Update the flight safety height of the drone based on the height of the obstacle and the set height difference.

[0050] Step S122: Determine the climbing slope of the drone according to the height difference between the updated flight safety height and the current flight height, and the horizontal distance between the drone and the obstacle. Then judge the magnitude relationship between the climbing slope and the preset threshold. If the climbing slope is greater than the preset threshold, execute step S123. If the climbing slope is not greater than the preset threshold, execute step S124.

[0051] Step S123: In response to the climbing slope being greater than the preset threshold, control the drone to circle and fly to the updated flight safety height.

[0052] Step S124: In response to the climbing slope being less than or equal to the preset threshold, control the drone to climb straight to the updated flight safety height.

[0053] It can be understood that after determining the existence of an obstacle, it is necessary to increase the flight height of the drone, and the height obtained by adding the height H3 of the obstacle and the set height difference H2 can meet the safe passage of the drone over the obstacle. Therefore, the flight safety height H4 of the drone can be updated based on the height H3 of the obstacle and the set height difference H2. Therefore, the drone needs to climb from the current flight height H1 to the updated flight safety height H4. However, the climbing of the drone is limited by the slope. Therefore, climbing obstacle avoidance can be divided into two cases: as Figure 5 shown, Figure 5 is a process display schematic diagram of avoiding obstacles by straight climbing in an application scenario of the present application. If the height difference between the drone and the obstacle is small and the distance is far, that is, the climbing slope of the drone is small, then the plane can climb straight to the flight safety height H4; on the contrary, as Figure 4 shown, Figure 4It is a schematic diagram showing the process of avoiding obstacles by circling and climbing in an application scenario of the present application. If the distance between the drone and the obstacle is close and the drop is large, that is, the climbing slope of the drone is too large, then it is necessary to climb to the flight safety altitude H4 by circling. It can be understood that a large climbing slope means that the corresponding climbing angle α is large, and a large climbing slope means that the corresponding climbing angle α is small. In one embodiment, the preset slope can be set to 15%; for example, when the height difference between the updated flight safety altitude H4 and the current flight altitude H1 is 3 meters, and the horizontal distance between the drone and the obstacle is greater than 20 meters, the climbing slope is less than 15%, and the flight altitude can be increased by a straight climbing method; for another example, when the height difference between the updated flight safety altitude H4 and the current flight altitude H1 is greater than 3 meters, and the horizontal distance between the drone and the obstacle is 20 meters, the climbing slope is greater than 15%, and the flight altitude is increased by circling and climbing.

[0054] See also Figure 6 , Figure 6 1 is a flow chart of the second embodiment of the method for avoiding obstacles when landing a drone of the present application. The method for avoiding obstacles when landing a drone of the present application comprises the following steps:

[0055] Step S61: When the UAV is in the level flight stage of landing, use radar to monitor whether there is the obstacle within a preset range in front of the UAV.

[0056] Please combine Figure 7 , Figure 7 It is a display schematic diagram of determining obstacles by radar in an application scenario of the present application. Specifically, a millimeter wave radar can be installed at the nose position of the drone. The millimeter wave radar can calculate the distance, speed and direction of the obstacle by using the reflected electromagnetic waves. When the radar is used to monitor obstacles within a preset range in front of the drone, the monitoring range is determined by the parameters of the radar. For example, the parameters of the radar can be: horizontal field of view angle 20 degrees, vertical field of view angle 15 degrees, and maximum detection distance 240 meters. After the radar beam hits the obstacle plane S1, due to the large differences in the shape and surface conditions of the obstacles, not every radar beam in the radar beam projection area S2 will reflect back the electromagnetic wave, so the radar can only calculate the information of the point P with a stronger echo; due to the characteristics of radar measurement, the millimeter wave radar cannot accurately describe the specific shape and exact position of the obstacle, and can only reflect the relevant information of the characteristic points on the obstacle. Therefore, combining multiple characteristic points can reflect the characteristic information of the obstacle to a certain extent through the optimization of the algorithm, and then determine the distance, speed and direction of the obstacle.

[0057] Step S62: If there is an obstacle in the forward flight path, reduce the flight speed of the drone and increase the altitude of the drone until no obstacle is detected within the range of the set altitude difference directly in front of the drone; wherein, the flight speed of the drone is negatively correlated with the distance between the drone and the obstacle.

[0058] Please combine Figure 8 , Figure 8 is a schematic diagram showing the process of avoiding obstacles by radar in an application scenario of the present application. Specifically, when the radar detects an obstacle Q, the drone will perform a deceleration and climb section AA to avoid the obstacle. During the climb, it is necessary to limit the flight speed according to the distance between the drone and the obstacle Q. For example, the drone will be braked to a stop before the drone reaches a safe distance (for example, it can be 50 meters) from the obstacle Q. During the climb, if no obstacle Q is detected within the range of the set altitude difference directly in front of the drone and directly in front of the drone in the field of view of the radar, it means that the current flight altitude of the drone is greater than the altitude of the obstacle plus the set altitude difference. At this time, the drone has reached the flight safety altitude and can stop climbing.

[0059] Further, in an embodiment, after the above step S62, the method for avoiding obstacles during landing of the drone in the present application further includes:

[0060] Step S63: Control the drone to fly horizontally, and after detecting that the drone has flown over the obstacle, reduce the flight altitude of the drone to restore to the flight altitude and flight speed before the increase.

[0061] Please continue to combine Figure 8 , after the drone climbs to the flight safety altitude, it can fly horizontally to pass the obstacle Q, and then perform a descent and recovery section CC after the drone flies through the horizontal obstacle avoidance section BB to restore the originally designed flight altitude H1 of the drone. In addition, it is possible to start accelerating until the originally designed flight speed is restored while stopping climbing, so as to realize real-time obstacle avoidance using the radar to avoid obstacles Q such as terrain and buildings that may be encountered.

[0062] Please refer to Figure 9 , Figure 9 is a schematic flowchart of the third embodiment of the method for avoiding obstacles during landing of the drone in the present application. The method for avoiding obstacles during landing of the drone in this embodiment includes the following steps:

[0063] Step S91: Receive the path instruction for the landing of the drone; wherein, the path instruction at least includes the position information of the descending and hovering point of the drone.

[0064] During the flight of the drone, the user can click on any position on the map interface to edit the landing route of the drone. When editing the landing route, a descent hovering point needs to be selected. It can be understood that during the time of editing the landing route, the drone still maintains its original state of flight and will only generate the landing route and form the landing path command at the moment after confirming the landing. After receiving the landing path command, the drone can be guided to fly towards the descent hovering point.

[0065] Step S92: Obtain the current position of the drone, and select the one with the higher altitude among the position information of the current position and the descent hovering point as the actual hovering point altitude.

[0066] The landing route starts from the current position of the drone, and the descent hovering point is a preselected point for hovering and descending. It can be understood that when the altitude of the current position of the drone is lower than the altitude of the descent hovering point, during the process of guiding the drone to fly from the current position to the descent hovering point, it is necessary to increase the flight altitude to the altitude of the descent hovering point. At this time, the altitude of the descent hovering point is the actual hovering point altitude. When the altitude of the current position of the drone is higher than the altitude of the descent hovering point, during the process of guiding the drone to fly from the current position to the descent hovering point, since a higher altitude can ensure flight safety, there is no need to reduce the flight altitude. At this time, the altitude of the current position can be used as the actual hovering point altitude.

[0067] Step S93: Enter the level flight phase with the actual hovering point altitude as the flight altitude and the area corresponding to the descent hovering point as the end point.

[0068] Therefore, when the actual hovering point altitude is the altitude of the descent hovering point, it means that the altitude of the descent hovering point is higher than the altitude of the current position of the drone. Therefore, during the level flight phase of the drone transferring from the current position to the descent hovering point, it is necessary to use the altitude of the descent hovering point as the flight altitude and the position of the descent hovering point as the end point; when the actual hovering point altitude is the altitude of the current position of the drone, it means that the altitude of the descent hovering point is lower than the altitude of the current position of the drone. Therefore, during the level flight phase of the drone transferring from the current position to the descent hovering point, it is necessary to use the altitude of the current position as the flight altitude and the airspace area corresponding to the descent hovering point as the end point.

[0069] Step S94: When the drone is in the level flight phase of landing, determine whether there are obstacles in the forward flight path; wherein, the height difference between the current flight altitude of the drone and the height of the obstacle is less than the set height difference.

[0070] Step S95: If there is an obstacle in the forward flight path, control the drone to increase the flight altitude to avoid the obstacle.

[0071] During the level flight stage when the UAV transfers from the starting position to the actual hovering point, the aircraft flies in a straight line horizontally and may encounter obstacles such as terrain and buildings. When it is determined that there are obstacles in the forward flight path, that is, the height difference between the current flight height of the UAV and the height of the obstacle is less than the set height difference, the UAV can be controlled to increase its flight height so that the flight height of the UAV is greater than the height of the obstacle plus the set height difference, so as to avoid the obstacle. Steps S94 and S95 in this embodiment are basically similar to steps S11 and S12 in the first embodiment of the above-mentioned landing obstacle avoidance method of the UAV, and will not be elaborated here.

[0072] Further, in one embodiment, the position information of the descending hovering point further includes the hovering radius; after the above step S95 in the landing obstacle avoidance method of the UAV of the present application, it further includes:

[0073] Step S96: Taking the height of the actual hovering point as the starting landing height, controlling the UAV to fly to the area corresponding to the descending hovering point, and hovering and landing with the vertical line where the descending hovering point is located as the axis based on the hovering radius.

[0074] Please refer to Figure 11 , Figure 11 which is a schematic diagram showing the landing route in an application scenario of the present application. The landing route starts from the current position A1 of the UAV, guides the UAV to horizontally transfer and fly towards the area corresponding to the descending hovering point A2, and hovers and descends at the descending hovering point A2.

[0075] Please refer to Figure 10 , Figure 10 which is Figure 9 a schematic flowchart of an embodiment of step S93 in

[0076] Step S931: Determine whether the height of the current position is less than the height in the position information of the descending hovering point. If the height of the current position is less than the height in the position information of the descending hovering point, then execute step S932; if the height of the current position is greater than or equal to the height in the position information of the descending hovering point, then execute step S933.

[0077] Step S932: In response to the height of the current position being less than the height in the position information of the descending hovering point, control the UAV to hover and fly from the current position to the height of the actual hovering point, and then enter the level flight stage with the height of the actual hovering point as the flight height and the descending hovering point as the end point.

[0078] Please refer to Figure 12 , Figure 12It is a schematic diagram showing the landing route in another application scenario of the present application. In the landing route, the descending turning point is a preselected point for turning and descending, and the height H2 of the descending turning point is the flight safety height selected by the system. If the height H1 of the current position is lower than the height H2 of the descending turning point, then the drone needs to first climb to the flight safety height. For example, it can climb to the height H2 of the descending turning point by turning and ascending, then maintain the height H2 of the descending turning point and fly horizontally until it enters the descending turn at the descending turning point and then descends in height.

[0079] Step S933: In response to the height of the current position being greater than or equal to the height in the position information of the descending turning point, control the drone to enter the horizontal flight phase with the height of the current position as the flight height and the airspace area corresponding to the descending turning point as the end point.

[0080] Please refer to Figure 13 , Figure 13 It is a schematic diagram showing the landing route in yet another application scenario of the present application. If the height H1 of the current position is higher than the height H2 of the descending turning point, then the drone is already above the flight safety height. Therefore, it only needs to maintain the height H1 of the current position and fly horizontally until it enters the descending turn at the descending turning point and then descends in height.

[0081] Please refer to Figure 14 , Figure 14 It is a schematic flowchart of the fourth embodiment of the landing obstacle avoidance method for the drone of the present application. The landing obstacle avoidance method for the drone in this embodiment includes the following steps:

[0082] Step S141: Receive the path instruction for the landing of the drone; wherein, the path instruction at least includes the position information of the descending turning point of the drone.

[0083] Step S142: Obtain the current position of the drone, and select the higher one of the height in the position information of the current position and the descending turning point as the actual turning point height.

[0084] Step S143: Enter the horizontal flight phase with the actual turning point height as the flight height and the area corresponding to the descending turning point as the end point.

[0085] Step S144: When the drone is in the horizontal flight phase of landing, determine whether there is an obstacle in the forward flight path; wherein, the height difference between the current flight height of the drone and the height of the obstacle is less than the set height difference.

[0086] Step S145: If there is an obstacle in the forward flight path, control the drone to increase the flight height to avoid the obstacle.

[0087] Steps S141 to S145 in this embodiment are basically similar to steps S91 to S95 in the third embodiment of the above-mentioned landing obstacle avoidance method for drones, and will not be elaborated here.

[0088] Further, the drone is a vertical takeoff and landing fixed-wing drone, and the path instruction further includes the mode switching altitude and the position information of the landing point; after the above-mentioned step S145, the landing obstacle avoidance method for the drone of the present application further includes:

[0089] Step S146: Control the drone to circle and land to the mode switching altitude, then fly horizontally to above the landing point with the mode switching altitude as the flight altitude, and vertically land at the landing point.

[0090] Please continue to refer to Figure 11 , in an application scenario, during the flight of the drone, the user can click on any position on the map interface to edit the landing route and form a path instruction for landing. First, click on a position to obtain the longitude and latitude of the landing point A4, then select another position to obtain the longitude and latitude of the descending and circling point A2. In addition, the content that needs to be edited includes: the altitude of the descending and circling point A2, the radius of the descending and circling circle, the mode switching altitude H3, the altitude of the landing point A4, etc. The landing route starts from the current position A1 of the drone, guides the drone to fly towards the descending and circling point A2, and descends while circling at the descending and circling point A2. The path of the descending and circling is a spiral, and the end of the spiral will reach the mode switching altitude H3, then break away from the circle and fly towards the landing point A4.

[0091] In one embodiment, the above-mentioned step S146 may specifically include: controlling the drone to circle and land to the mode switching altitude in the fixed-wing mode, then switching the drone to the rotor mode, flying horizontally to above the landing point with the mode switching altitude as the flight altitude, and then vertically landing at the landing point.

[0092] Specifically, the drone is a vertical takeoff and landing fixed-wing drone, which has two flight modes: the fixed-wing mode and the rotor mode. When the drone circles and lands to a certain distance (i.e., the mode switching altitude) close to the landing point in the fixed-wing mode, it starts to switch the mode and decelerate, switches from the fixed-wing mode to the rotor mode, and finally hovers at 0 speed above the landing point in the rotor mode and finally vertically lands at the landing point on the ground.

[0093] Please refer to Figure 15 , Figure 15It is a schematic diagram of the frame structure of an embodiment of the drone in this application. The drone 15 in this embodiment includes a fuselage 150, a processor 151, and a memory 152; the processor 151 and the memory 152 are accommodated inside the fuselage 150. Among them, the memory 152 stores program instructions, and the processor 151 retrieves the program instructions from the memory 152 to execute the steps of any of the above embodiments of the landing obstacle avoidance method for drones.

[0094] Specifically, the processor 151 is used to control itself, the fuselage 150, and the memory 152 to implement the steps of any of the above embodiments of the landing obstacle avoidance method for drones. The processor 151 can also be called a CPU (Central Processing Unit). The processor 151 may be an integrated circuit chip with signal processing capabilities. The processor 151 can also be a general-purpose processor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc. In addition, the processor 151 can be implemented jointly by integrated circuit chips.

[0095] For the specific content of how the processor 151 in this application implements the landing obstacle avoidance method for drones, please refer to the content in the above embodiments of the landing obstacle avoidance method for drones, which will not be elaborated here.

[0096] Please refer to Figure 16 , Figure 16 It is a schematic diagram of the structure of an embodiment of the computer-readable storage medium in this application. The computer-readable storage medium 16 in this application stores program instructions 160 thereon, and when the program instructions 160 are executed by a processor, the steps in any of the above embodiments of the landing obstacle avoidance method for drones are implemented.

[0097] The computer-readable storage medium 16 can specifically be a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk, or an optical disc, etc., which can store the program instructions 160, or it can also be a server storing the program instructions 160. The server can send the stored program instructions 160 to other devices for running, or it can also run the stored program instructions 160 by itself.

[0098] In several embodiments provided by the present application, it should be understood that the disclosed methods, devices, and apparatuses can be implemented in other ways. For example, the device and apparatus embodiments described above are merely illustrative. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the displayed or discussed coupling, direct coupling, or communication connection to each other can be through some interfaces. The indirect coupling or communication connection of the device or unit can be in electrical, mechanical, or other forms.

[0099] The units described as separate components may or may not be physically separated. The components displayed as units may or may not be physical units, that is, they can be located in one place or distributed to multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0100] In addition, each functional unit in various embodiments of the present application can be integrated in a processing unit, or each unit can exist physically alone, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be implemented in the form of hardware or in the form of a software functional unit.

[0101] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present application, in essence, or the part that contributes to the prior art, or all or part of this technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to enable a computer device (which can be a personal computer, a server, or a network device, etc.) or a processor to execute all or part of the steps of the methods in various embodiments of the present application. The aforementioned storage medium includes: USB flash drives, mobile hard disks, read-only memories (ROMs), random access memories (RAMs), magnetic disks, or optical discs and other various media that can store program codes.

Claims

1. A landing obstacle avoidance method for an unmanned aerial vehicle, characterized in that, the landing obstacle avoidance method for the unmanned aerial vehicle includes: Receiving a path instruction for the landing of the unmanned aerial vehicle; wherein, the path instruction at least includes position information of a descending hovering point of the unmanned aerial vehicle; Obtaining the current position of the unmanned aerial vehicle, and selecting the higher one of the height in the current position and the position information of the descending hovering point as the actual hovering point height, Taking the actual hovering point height as the flight height and taking the area corresponding to the descending hovering point as the end point, entering a level flight stage; wherein, in response to the height of the current position being less than the height in the position information of the descending hovering point, controlling the unmanned aerial vehicle to hover and fly from the current position to the actual hovering point height, and then taking the actual hovering point height as the flight height and taking the descending hovering point as the end point, entering the level flight stage; When the unmanned aerial vehicle is in the level flight stage of landing, determining whether there is an obstacle in the forward flight path; wherein, the height difference between the current flight height of the unmanned aerial vehicle and the height of the obstacle is less than a set height difference; If there is the obstacle in the forward flight path, controlling the unmanned aerial vehicle to increase the flight height to avoid the obstacle.

2. The landing obstacle avoidance method for an unmanned aerial vehicle according to claim 1, characterized in that, the step of determining whether there is an obstacle in the forward flight path when the unmanned aerial vehicle is in the level flight stage of landing includes: When the unmanned aerial vehicle is in the level flight stage of landing, obtaining the terrain heights of a plurality of sampling points within a set distance in front based on the flight route, and then determining whether there is the obstacle in the forward flight path according to the magnitude relationship between the highest terrain height among the plurality of terrain heights and the difference between the current flight height and the set height difference.

3. The landing obstacle avoidance method for an unmanned aerial vehicle according to claim 2, characterized in that, the plurality of sampling points are arranged at equal intervals along the flight direction of the unmanned aerial vehicle.

4. The landing obstacle avoidance method for an unmanned aerial vehicle according to claim 1, characterized in that, the step of determining whether there is an obstacle in the forward flight path when the unmanned aerial vehicle is in the level flight stage of landing includes: When the unmanned aerial vehicle is in the level flight stage of landing, using a radar to monitor whether there is the obstacle within a preset range in front of the unmanned aerial vehicle; the step of controlling the unmanned aerial vehicle to increase the flight height to avoid the obstacle includes: Reducing the flight speed of the unmanned aerial vehicle and increasing the height of the unmanned aerial vehicle until the obstacle is not detected within the range of the set height difference directly in front of the unmanned aerial vehicle; wherein, the flight speed of the unmanned aerial vehicle is negatively correlated with the distance between the unmanned aerial vehicle and the obstacle.

5. The landing obstacle avoidance method for an unmanned aerial vehicle according to claim 4, characterized in that, after the step of reducing the flight speed of the unmanned aerial vehicle and increasing the height of the unmanned aerial vehicle until the obstacle is not detected within the preset range in front of the unmanned aerial vehicle, includes: The drone is controlled to fly horizontally, and after detecting that the drone flies over the obstacle, the flight altitude of the drone is reduced to restore the flight altitude and flight speed before the increase.

6. The method for avoiding obstacles when landing a drone according to any one of claims 1 to 5, It is characterized in that If the obstacle exists in the front flight path, the step of controlling the drone to increase the flight altitude to avoid the obstacle includes: Updating the safe flight altitude of the UAV based on the height of the obstacle and the set altitude difference; Determining a climbing slope of the UAV according to a height difference between the updated flight safety altitude and the current flight altitude and a horizontal distance between the UAV and the obstacle; In response to the climbing gradient being greater than a preset threshold, controlling the drone to hover to the updated flight safety altitude; In response to the climbing gradient being less than or equal to the preset threshold, the UAV is controlled to climb to the updated flight safety altitude.

7. The method for avoiding obstacles when landing a drone according to claim 1, It is characterized in that The step of entering the level flight stage with the actual circling point height as the flight height and the area corresponding to the descending circling point as the end point comprises: Determine whether the altitude of the current position is less than the altitude in the position information of the descending circling point; In response to the altitude of the current position being greater than or equal to the altitude in the position information of the descending circling point, the drone is controlled to take the altitude of the current position as the flight altitude and take the upper area corresponding to the descending circling point as the end point to enter the level flight stage.

8. The method for avoiding obstacles when landing a drone according to claim 1 or 7, It is characterized in that The position information of the descending circling point also includes a circling radius; After the step of taking the actual circling point height as the flight height and the area corresponding to the descending circling point as the end point and entering the level flight stage, the method includes: The actual circling point height is used as the starting landing height, the UAV is controlled to fly to the area corresponding to the descending circling point, and the UAV is circled and landed based on the circling radius with the vertical line where the descending circling point is located as the axis.

9. The method for avoiding obstacles when landing a drone according to claim 1 or 7, It is characterized in that The UAV is a vertical take-off and landing fixed-wing UAV, and the path instruction also includes the mode switching height and the location information of the landing point; After the step of taking the actual circling point height as the flight height and the area corresponding to the descending circling point as the end point and entering the level flight stage, the method includes: The drone is controlled to hover and land to the mode switching height, and then flies horizontally to the sky above the landing point with the mode switching height as the flight height, and lands vertically to the landing point.

10. The method for avoiding obstacles when landing a drone according to claim 9, It is characterized in that The step of controlling the drone to hover and land to the mode switching height, then flying horizontally to the sky above the landing point with the mode switching height as the flight height, and landing vertically to the landing point includes: Control the drone to circle and land at the mode switching altitude in fixed-wing mode, then switch the drone to rotor mode, fly horizontally to above the landing point at the mode switching altitude, and then vertically land at the landing point.

11. A drone, characterized in that, it includes: a fuselage, a processor and a memory; The processor and the memory are housed inside the fuselage. Among them, the memory stores program instructions, and the processor retrieves the program instructions from the memory to execute the landing obstacle avoidance method of the drone according to any one of claims 1-10.

12. A computer-readable storage medium, characterized in that, it stores program instructions thereon, and when the program instructions are executed by a processor, the landing obstacle avoidance method of the drone according to any one of claims 1 to 10 is implemented.

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