TWI785442B - Unmanned aerial vehicle and its flight control method - Google Patents

Abstract

A flight control method for an unmanned aerial vehicle, comprising the following steps: obtaining a non-rotating The rotary radar module detects at least a first echo signal in a front area and a second echo signal in a bottom area. According to the first echo signal and the second echo signal, a spatial information of an obstacle located in front of the UAV is obtained, and the spatial information includes at least a horizontal distance of the obstacle relative to the UAV and a relative distance between the obstacle and the UAV. A height difference of a ground. An early warning signal is generated when the horizontal distance and the height difference meet an early warning condition. Wherein the non-rotating radar module includes a forward-looking radar for detecting the first echo signal and a ground-following radar for detecting the second echo signal, and the forward-looking radar has vertical height identification capability.

Description

Unmanned aerial vehicle and its flight control method

The present invention relates to an unmanned aerial vehicle, and in particular to an unmanned aerial vehicle for obstacle avoidance and/or terrain detection and a flight control method thereof.

An unmanned aerial vehicle (UAV, Unmanned Aerial Vehicle) can be widely used in outdoor or indoor environments to perform various tasks such as monitoring or observation. UAVs can generally be operated remotely by users, and can also automatically navigate and fly through programs and coordinates. UAVs can be equipped with equipment such as cameras and/or detectors to provide images during flight, or various information such as weather, atmospheric conditions, and radiation levels. The drone can also have a cargo compartment for loading various items. Therefore, the diverse application potential of UAVs makes it continue to flourish.

When UAVs are used in automatic flight inspections, they often encounter various possible terrains or obstacles. Therefore, how to make the UAV effectively and reliably avoid terrain or obstacles, and avoid collision or damage has become the focus of attention of relevant personnel in this field.

The invention provides a flight control method of an unmanned aerial vehicle, which can effectively avoid obstacles.

The present invention also provides a drone that can effectively avoid obstacles.

Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

The flight control method of the unmanned aerial vehicle of the present invention comprises the following steps: Step 1-1: Obtain at least one first echo signal and a bottom side area detected by a non-rotating radar module of the unmanned aerial vehicle at least one second echo signal; step 1-2: Obtain a spatial information of an obstacle according to the first echo signal and the second echo signal, the spatial information at least includes the obstacle relative to the UAV A horizontal distance and a height difference of the obstacle relative to a ground; and step 1-3: generating an early warning signal when the horizontal distance and the height difference meet an early warning condition; wherein the non-rotating radar module includes detecting the A forward-looking radar for detecting the first echo signal and a ground-following radar for detecting the second echo signal, the forward-looking radar has vertical height identification capability.

In an embodiment of the present invention, in step 1-2, obtaining the horizontal distance and the height difference includes the following steps: using the first echo signal detected by the forward-looking radar to obtain the relative distance between the obstacle and the uninhabited person. A first relative distance D1 of the drone and a first angle θ1, the first angle θ1 is between the obstacle and an imaginary line of the drone and an imaginary plane; a first height is obtained according to the following formula Difference H1; H1=D1×sinθ1

Use the ground-following radar to obtain a height difference H _UAV of the UAV relative to the ground, and obtain the height difference H _Ta between the obstacle and the ground according to the following formula; H _Ta =H _UAV -H1

The horizontal distance of the obstacle relative to the UAV is obtained according to the following formula: D _Ta =D1×cosθ1

In an embodiment of the present invention, the aforementioned forward-looking radar includes a short-range antenna and a long-range antenna.

In an embodiment of the present invention, the above-mentioned short-distance antenna has a detection distance within 100m, and the long-distance antenna has a detection distance between 50m and 300m.

In an embodiment of the present invention, wherein in step 1-2, obtaining the horizontal distance and the height difference includes the following steps: using a long-distance echo signal detected by the long-distance antenna to obtain the relative distance between the obstacle and the unmanned person A first relative distance D1 of the drone and a first angle θ1, the first angle θ1 is between the obstacle and an imaginary line of the drone and an imaginary plane; a first height is obtained according to the following formula Difference H1; H1=D1×sinθ'

Among them, θ' is the addition between the first included angle θ1 and a pitch angle of the UAV; a height difference H _UAV of the UAV relative to the ground is obtained by using the ground-following radar, and the obstacle is obtained according to the following formula The height difference H _Ta between the object and the ground; H _Ta =H _UAV -H1

The horizontal distance of the obstacle relative to the UAV is obtained according to the following formula: D _Ta =D1×cosθ'

In an embodiment of the present invention, in step 1-2, the obtaining of the horizontal distance and the height difference includes the following steps: using a short-distance echo signal detected by the short-distance antenna to obtain the relative distance between the obstacle and the uninhabited person. A second relative distance D2 of the machine and a second included angle θ2, the second included angle θ2 is between the obstacle and an imaginary line of the UAV and an imaginary plane; a second height difference H2 is obtained according to the following formula; H2=D2×sinθ2

Use the ground-following radar to obtain a height difference H _UAV of the UAV relative to the ground, and obtain the height difference H _Ta between the obstacle and the ground according to the following formula; H _Ta =H _UAV -H2

The horizontal distance of the obstacle relative to the UAV is obtained according to the following formula: D _Ta =D2×cosθ2

A flight control method of the present invention includes the following steps: Step 2-1: Obtain at least one first echo signal of a front area detected by a non-rotating radar module of the drone and at least one of a bottom area A second echo signal; step 2-2: obtain a horizontal distance of an obstacle according to the first echo signal and the second echo signal, and obtain the UAV relative to a ground according to the second echo signal a height difference; step 2-3: judging whether the horizontal distance and/or the height difference at multiple time points meet a slope terrain condition; and step 2-4: when the slope terrain condition is met, according to a spatial information Adjusting a flight trajectory of the UAV, wherein the spatial information includes at least the horizontal distance and/or the height difference; wherein the non-rotating radar module includes at least one forward-looking radar for detecting the first echo signal and a detection A ground-following radar for measuring the second echo signal, and the forward-looking radar has a vertical height identification capability.

In an embodiment of the present invention, in step 2-2, the acquisition of the horizontal distance includes the following steps: using a long-distance echo signal detected by the long-distance antenna to obtain a first distance of the obstacle relative to the UAV A relative distance D1 and a first angle θ1, the first angle θ1 is between the obstacle and an imaginary line of the UAV and an imaginary plane; according to the following formula, the obstacle relative to the UAV is obtained. The horizontal distance: D _Ta =D1×cosθ'

Wherein, θ' is the addition between the first angle θ1 and a pitch angle of the UAV.

In an embodiment of the present invention, in step 2-2, the acquisition of the horizontal distance includes the following steps: using a short-distance echo signal detected by the short-distance antenna to obtain a first distance of the obstacle relative to the UAV Two relative distances D2 and a second angle θ2, the second angle θ2 is between the obstacle and an imaginary line of the UAV and an imaginary plane; get the obstacle relative to the UAV according to the following formula The horizontal distance: D _Ta =D2×cosθ2

In an embodiment of the present invention, in the above steps 2-4, when the slope terrain condition is met, dynamically compensate a flying height of the drone relative to a terrain according to the spatial information.

The drone of the present invention includes an aircraft and a non-rotating radar module. The non-rotating radar module is installed on the aircraft. The non-rotating radar module includes at least one forward-looking radar and one ground-following radar. The forward-looking radar has vertical height identification capability; wherein, the forward-looking radar detects a At least one first echo signal in the front area, the ground-following radar detects at least one second echo signal in a bottom side area, and the position in front of the UAV is obtained according to the first echo signal and the second echo signal A spatial information of an obstacle, and an early warning signal is generated when the spatial information meets a warning condition.

Based on the above, the UAV and its flight control method provided by the present invention can effectively and reliably avoid terrain or obstacles, and avoid collision or damage by setting a non-rotating radar module.

In order to make the above-mentioned features and advantages of the present invention more comprehensible, the following specific embodiments are described in detail together with the accompanying drawings.

10: Drone

11: Non-rotating radar module

111:Forward-looking radar

111a: Front detection range

1111:Short distance antenna

1111a: Front short-range detection range

1113:Long distance antenna

1113a: Front long-distance detection range

113: Ground imitation radar

113a: Bottom detection range

115: processing device

117: Rear view radar

13: Aircraft

20: Adjusted flight trajectory

F: front area

W _r1 : the first echo signal

W _r1-1 : Long distance echo signal

W _r1-2 : short distance echo signal

W _r2 : Second echo signal

W _t1 : first radar signal

W _t2 : second radar signal

B _a , B _b , B _c : Obstacles

D1: The first relative distance

D2: Second relative distance

D _Ta : Horizontal distance

G: Ground

H1: the first height difference

H2: second height difference

H _Ta : height difference

H _UAV : height difference

H _UAV1 : front height difference

H _UAV2 : intermediate height difference

H _UAV3 : Rear height difference

L _I : imaginary line

P _I : imaginary plane

θ1: the first included angle

θ2: pitch angle

U: Bottom side area

1-1, 1-2, 1-3: Steps

2-1, 2-2, 2-3: Steps

[Fig. 1] is a schematic diagram of the appearance of a drone according to an embodiment of the present invention.

[FIG. 2] is a schematic functional block diagram of an unmanned aerial vehicle according to an embodiment of the present invention.

[FIG. 3] is a flow chart of a flight control method according to an embodiment of the present invention.

[Fig. 4] is a schematic diagram of the UAV performing obstacle avoidance warning in an embodiment of the present invention.

[FIG. 5A] to [FIG. 5B] are schematic diagrams of the UAV performing obstacle avoidance warning in the first embodiment of the present invention.

[Fig. 6] is a schematic diagram of the UAV performing obstacle avoidance warning in the second embodiment of the present invention.

[FIG. 7] is a schematic flow chart of the flight control method of the third embodiment of the present invention.

[Fig. 8] is a schematic diagram of the UAV performing obstacle avoidance warning in the third embodiment of the present invention.

The aforementioned and other technical contents, features and effects of the present invention will be clearly presented in the following detailed description of a preferred embodiment with reference to the drawings. The directional terms mentioned in the following embodiments, such as: up, down, left, right, front or back, etc., are only directions referring to the attached drawings. Accordingly, the directional terms are used to illustrate and not to limit the invention.

Referring to "Fig. 1" and "Fig. 2", "Fig. 1" is a schematic view of the appearance of the drone 10 according to an embodiment of the present invention, and "Fig. 2" is the function of the drone 10 shown in "Fig. 1" A schematic diagram of a block. The drone 10 includes a non-rotating radar module 11 and an aircraft 13 . The non-rotating radar module 11 is mounted on the aircraft 13 . The non-rotating radar module 11 can detect obstacles and/or terrain features, so that the UAV 10 can fly safely and avoid collisions.

In this embodiment, the non-rotating radar module 11 includes a forward-looking radar 111 , a ground-following radar 113 , a processing device 115 and a rear-looking radar 117 . Referring to "Fig. 2", the forward-looking radar 111 further includes a short-distance antenna 1111 and a long-distance antenna 1113, the forward-looking radar 111, the rear-looking radar 117 and the ground-following radar 113 are electrically connected to the processing device 115 connected, and can perform signal transmission and/or exchange with the processing device 115. In this embodiment, the short-distance antenna 1111 and the long-distance antenna 1113 are radar modules whose emission sources are electromagnetic waves. The short-distance antenna 1111 has a detection distance within 100m, and the best short-distance detection range is Between 50m and 80m. The long-distance antenna 1113 has a detection range between 50m and 300m, and the optimal long-distance detection range is between 60m and 160m.

In this embodiment, in terms of hardware, the forward-looking radar 111 itself has both the ability to identify the horizontal distance and the ability to identify the vertical height. Hereinafter, the forward-looking radar 111 includes the short-range antenna 1111 and the long-range antenna 1113 for example, and according to different applications, the forward-looking radar 111 may only include the short-range antenna 1111 or the long-range antenna 1113 .

In the drone 10 of this embodiment, the non-rotating radar module 11 is fixedly installed on the aircraft 13 and does not rotate relative to the aircraft 13 . The non-rotating radar module 11 does not have mechanical bearings or mechanical structures for rotation, which can reduce damage Possibly, increase service life and reduce costs. The non-rotating radar module 11 can detect without rotating, which can effectively avoid time delay or error caused by the time required for rotating. At the same time, the drone 10 does not need to consider the calibration of the rotating mechanical structure during manufacture, which can effectively improve production efficiency and reduce costs. The non-rotating radar module 11 can also avoid distance/height detection errors caused by displacement caused by rotation. The specific structure and operation details will be described in detail below.

The aircraft 13 shown in Fig. 1 is only an example. The present invention does not limit the structure of the aircraft 13 , nor does it limit the power mode and source of the aircraft 13 . As long as the UAV 10 can fly through the aircraft 13, it is within the scope of the present invention.

Referring to "Fig. 3" and "Fig. 4", "Fig. 3" is a flow chart of the flight control method of the UAV according to an embodiment of the present invention, and "Fig. 4" is an example of the UAV performing obstacle avoidance warning according to an embodiment of the present invention. schematic diagram. The following embodiments are illustrated with the UAV 10 in "Fig. 1" and "Fig. 2". The UAV 10 is flying along the left side of "Fig. 4" to the right, and there is an obstacle in front of the UAV 10. Object B _a . The flight control method of the UAV 10 includes the following steps.

In step 1-1, at least one first echo signal W _r1 of a front area F detected by the non-rotating radar module 11 of the UAV 10 and a second echo signal of a bottom area U are obtained first. In the signal W _r2 , the front area F here refers to the front area of a flying direction of the UAV 10 . In this embodiment, the forward-looking radar 111 is used to send a first radar signal W _t1 , which is reflected by the obstacle B _a to generate the first echo signal W _r1 , and the ground-following radar 113 is used to send a second radar signal W t1 . The radar signal W _t2 is reflected by a ground G to generate the second echo signal W _r2 . The forward-looking radar 111 has a front detection range 111a, and the ground-following radar 113 has a bottom detection range 113a. The present invention is not limited thereto, and any radar device that can capture the front area F and the bottom area U can be used.

In step 1-2, according to the first echo signal W _r1 and the second echo signal W _r2 , a spatial information of the obstacle B _a in front of the UAV 10 and the UAV 10 relative to the ground are obtained. An altitude difference H _UAV of G. The spatial information at least includes a horizontal distance D _Ta of the obstacle B _a relative to the UAV 10 and a height difference H _Ta of the obstacle B _a relative to the ground G.

Next, in step 1-3, an early warning signal is generated when the horizontal distance D _Ta and the height difference H _Ta meet an early warning condition. For example, the judgment of the early warning condition may include any or a combination of the following: a . whether the horizontal distance D _Ta is less than a minimum safety distance; and b. whether a difference between the height difference H _UAV and the height difference H _Ta is less than a minimum safety value.

When it matches, it means that the UAV 10 may collide with the obstacle B _a soon, and the UAV 10 can change the flying state according to the warning signal, which can effectively avoid the collision between the UAV 10 and the obstacle B _a . The early warning signal can be directly or converted into other signals and transmitted wirelessly to a remote controller of an operator of the UAV 10, and in other examples, may also be directly transmitted to other electronic components of the UAV 10 And correct the flight path of the drone 10 .

Referring to "Figure 5A" and "Figure 5B", it is a schematic diagram of the UAV performing obstacle avoidance warning in the first embodiment of the present invention. In this embodiment, the long-distance antenna 1113 is used together with the ground imitation radar 113 for obstacle avoidance warning. In operation, the long-range antenna 1113 has a front long-range detection range 1113a, and the ground-following radar 113 has a bottom-side detection range 113a. Firstly, "Fig. 5A" is used to illustrate that in the aforementioned step 1-2, the acquisition of the horizontal distance D _Ta and the height difference H _Ta is as follows.

A first relative distance D1 and a first included angle θ1 of the obstacle B _a relative to the UAV 10 are obtained by using a long-distance echo signal W _r1-1 detected by the long-distance antenna 1113 . The first included angle θ1 is defined between an imaginary line L _I from the obstacle Ba to the drone 10 and an imaginary plane P _I. The imaginary line L _I is _a line segment connecting the UAV 10 to the obstacle Ba, and the imaginary plane P _I is the horizontal plane where the UAV 10 is located. Cooperating with the geometric relationship in "Fig. 5A", a first height difference H1 can be obtained according to the following equation.

H1=D1×sinθ1 (Formula 1)

Next, using the second echo signal W _r2 detected by the ground-following radar 113 to obtain a height difference H _UAV of the UAV 10 relative to the ground G, with the geometric relationship in Figure 5A, the obstacle can be obtained according to the following equation The height difference H _Ta between _Ba and the ground G. The height difference H _UAV is the height of the drone 10 , and the height difference H _Ta is the height of the obstacle Ba.

H _Ta =H _UAV -H1 (Formula 2)

The horizontal distance D _Ta of the obstacle Ba relative to the UAV 10 can be obtained according to the following equation.

D _Ta =D1×cosθ1 (Formula 3)

Thereby, the drone 10 can obtain the horizontal distance D _Ta relative to the obstacle _Ba and the height of the obstacle _Ba (that is, the height difference H _Ta ) through the forward-looking radar 111 .

On top of that, in other embodiments, considering that the UAV 10 may be tilted during flight to form _a pitch angle, and the distance of the obstacle Ba detected by the long-distance antenna 1113 is relatively far, it will make the calculation Therefore, the signal obtained by the long-distance antenna 1113 needs to be corrected or compensated. Referring to "Fig. 5B", in this embodiment, the UAV 10 is tilted by a pitch angle θ2, and in accordance with the geometric relationship of "Fig. 5B", the above (Formula 1) needs to be changed to the following (Formula 1').

H1=D1×sinθ' (Formula 1')

Wherein, θ' is the addition between the first angle θ1 and the pitch angle θ2 of the UAV 10. By considering the correction of the pitch angle θ2, the distance calculation error caused by the tilt of the UAV 10 can be compensated.

Referring to "Fig. 6", it is a schematic diagram of the UAV performing obstacle avoidance warning in the second embodiment of the present invention. The antenna 1111 has a front short-distance detection range 1111a, and the ground-following radar 113 has a bottom detection range 113a. , the following embodiments are still illustrated with the unmanned aerial vehicle 10 of "Fig. 1" and "Fig. 2". The unmanned aerial vehicle 10 flies along the left side of "Fig. An obstacle B _b .

In the aforementioned step 1-2, the horizontal distance D _Ta and the height difference H _Ta are obtained as follows.

A second relative distance D2 and a second included angle θ2 of an obstacle B _b relative to the UAV 10 are obtained by using a short-distance echo signal W _r1-2 detected by the short-distance antenna 1111 . The second included angle θ2 is defined between an imaginary line L _I from the obstacle B _b to the UAV 10 and an imaginary plane P _I. The imaginary line L _I is a line segment connecting the UAV 10 to the obstacle B _b , and the imaginary plane P _I is the horizontal plane where the UAV 10 is located. Cooperating with the geometric relationship in "Fig. 6", a second height difference H2 can be obtained according to the following equation.

H2=D2×sinθ2 (Formula 4)

Using the second echo signal W _r2 detected by the ground-following radar 113, a height difference H _UAV of the UAV 10 relative to the ground can be obtained, and the distance between the obstacle B _b and the ground G can be obtained according to the following equation. This height difference H _Ta .

H _Ta =H _UAV -H2 (Formula 5)

The horizontal distance D _Ta of the obstacle B _b relative to the UAV 10 can be obtained according to the following equation.

D _Ta =D2×cosθ2 (Formula 6)

Thereby, the UAV 10 can obtain the horizontal distance D _Ta relative to the obstacle B _b through the short-distance antenna 1111 . Thereby, the UAV 10 can avoid the obstacle B _b accordingly, effectively avoiding collision.

Referring to "Fig. 7" and "Fig. 8", "Fig. 7" is a flow chart of the flight control method of the unmanned aerial vehicle according to the third embodiment of the present invention, and "Fig. 8" is the obstacle avoidance of the unmanned aerial vehicle according to the third embodiment of the present invention Schematic diagram of the warning. The following embodiments are illustrated with the UAV 10 of "Fig. 1" and "Fig. 2". The UAV 10 flies along the left side of "Fig. The flight is carried out on a sloped terrain T which can be considered to be equal to or exist an obstacle B _c . The flight control method of the UAV 10 includes the following steps.

In step 2-1, at least one first echo signal of a front area F detected by the non-rotating radar module 11 of the UAV 10 and at least one second echo signal W of a bottom area U are obtained. _r2 . In this embodiment, a second relative distance D2 and a second included angle θ2 of the obstacle _Bc relative to the UAV 10 are obtained by using a short-distance echo signal W _r1-2 detected by the short-distance antenna 1111, And the ground-following radar 113 is used to detect the second echo signal W _r2 reflected by the terrain T, where the second echo signal W _r2 includes a front echo signal, a rear echo signal and a The middle echo signals correspond to the echo signals received by a front area, a rear area and a middle area respectively, the front area is an area with an azimuth angle between +30° and +60°, and the rear area is an azimuth The region with angles between -60° and -31°, the intermediate region is the region with azimuth angles between -30° and +30°. The present invention is not limited thereto, and any radar device that can capture the front area F and the bottom area U can be used.

In step 2-2, a horizontal distance D _Ta of the obstacle B _c in front of the UAV 10 is obtained according to the first echo signal W _r1-2 and the second echo signal W _r2 , and according to the The second echo signal W _r2 obtains a height difference of the UAV 10 relative to the terrain T. In this embodiment, the height difference includes a A front height difference H _UAV1 , a rear height difference H _UAV3 and a middle height difference H _UAV2 .

Then, in step 2-3, it is judged whether the horizontal distance D _Ta and the height difference meet a slope terrain condition, for example, the slope terrain condition can include the following combination: c. whether the horizontal distance D _Ta is less than a Minimum safety distance; d. whether the middle height difference H _UAV2 is less than a minimum safety height; e. calculated according to the difference between the front side height difference H _UAV1 , the middle height difference H _UAV2 and the rear side height difference H _UAV3 An actual slope, whether the actual slope is higher than a preset slope.

Further, considering whether the slope terrain condition is satisfied or not may require a plurality of spatial data when the UAV 10 is in different positions, so that a certain accuracy can be achieved. In one embodiment, the horizontal distance D _Ta and the height difference of the UAV 10 are obtained at multiple time points as the basis for judgment.

In steps 2-4, when the slope terrain condition is met, a flight trajectory of the UAV 10 is adjusted according to a spatial information, as shown in Fig. 8 , the UAV 10 can fly along an adjusted flight trajectory 20 . Wherein the spatial information at least includes the horizontal distance D _Ta and the height difference.

Thereby, by detecting the horizontal distance D _Ta and the height difference at multiple time points, and coordinating with the judgment of the slope terrain condition, the UAV 10 can avoid the terrain and effectively avoid collisions.

In addition, in step 2-4, when the slope terrain condition is met, the UAV 10 can dynamically compensate a flying height (ie height difference) of the UAV 10 relative to a terrain according to the spatial information.

To sum up, the UAV and its flight control method according to the embodiment of the present invention, by setting a non-rotating radar module, can enable the UAV to avoid terrain or obstacles effectively and reliably, and avoid collision or damage.

10: Drone

111a: Front detection range

113a: Bottom detection range

F: front area

W _r1 : the first echo signal

W _r1-1 : Long distance echo signal

W _r1-2 : short distance echo signal

W _r2 : Second echo signal

W _t1 : first radar signal

W _t2 : second radar signal

B _a : Obstacles

D _Ta : Horizontal distance

G: Ground

H _Ta : height difference

H _UAV : height difference

U: Bottom side area

Claims (15)

A flight control method for an unmanned aerial vehicle, comprising the following steps: Step 1-1: Obtain at least one first echo signal of a front area detected by a non-rotating radar module of the unmanned aerial vehicle and at least one echo signal of a bottom area A second echo signal; step 1-2: Obtain a spatial information of an obstacle according to the first echo signal and the second echo signal, the spatial information at least includes a level of the obstacle relative to the UAV distance and a height difference of the obstacle relative to a ground; and step 1-3: generating an early warning signal when the horizontal distance and the height difference meet an early warning condition; wherein the non-rotating radar module includes detecting the first A forward-looking radar for the echo signal and a ground-following radar for detecting the second echo signal, the forward-looking radar has vertical height identification capability. The method according to claim 1, wherein in step 1-2, obtaining the horizontal distance and the height difference includes the following steps: using the first echo signal detected by the forward-looking radar to obtain the relative distance between the obstacle and the uninhabited person A first relative distance D1 of the drone and a first angle θ1, the first angle θ1 is between the obstacle and an imaginary line of the drone and an imaginary plane; a first height is obtained according to the following formula Difference H1; H1=D1×sinθ1 Use the ground-following radar to obtain a height difference H _UAV of the UAV relative to the ground, and obtain the height difference H _Ta between the obstacle and the ground according to the following formula; H _Ta = H _UAV -H1 obtains the horizontal distance of the obstacle relative to the UAV according to the following formula: D _Ta =D1×cosθ1. The method of claim 1, wherein the forward-looking radar includes a short-range antenna and a long-range antenna. The method according to claim 3, wherein the short-distance antenna has a detection range within 100m, and the long-distance antenna has a detection range between 50m and 300m. The method as described in claim 3, wherein in step 1-2, obtaining the horizontal distance and the height difference includes the following steps: using a long-distance echo signal detected by the long-distance antenna to obtain the relative distance between the obstacle and the uninhabited person A first relative distance D1 of the drone and a first angle θ1, the first angle θ1 is between the obstacle and an imaginary line of the drone and an imaginary plane; a first height is obtained according to the following formula Difference H1; H1=D1×sinθ' where, θ' is the addition between the first angle θ1 and a pitch angle of the UAV; using the ground-following radar to obtain a height difference H of the UAV relative to the ground _UAV , and the height difference H _Ta between the obstacle and the ground is obtained according to the following formula; H _Ta =H _UAV -H1 The horizontal distance of the obstacle relative to the UAV is obtained according to the following formula: D _Ta =D1× cos θ'. The method as described in claim 3, wherein in step 1-2, obtaining the horizontal distance and the height difference includes the following steps: using a short-distance echo signal detected by the short-distance antenna to obtain the relative distance between the obstacle and the uninhabited person A second relative distance D2 of the drone and a second angle θ2, the second angle θ2 is between the obstacle and an imaginary line of the drone and an imaginary plane; a second height is obtained according to the following formula Difference H2; H2=D2×sinθ2 Use the ground-following radar to obtain a height difference H _UAV of the UAV relative to the ground, and obtain the height difference H _Ta between the obstacle and the ground according to the following formula; H _Ta = H _UAV -H2 obtains the horizontal distance of the obstacle relative to the UAV according to the following formula: D _Ta =D2×cosθ2. A flight control method for an unmanned aerial vehicle, comprising the following steps: Step 2-1: Obtaining at least one first echo signal of a front area detected by a non-rotating radar module of the unmanned aerial vehicle and at least one echo signal of a bottom area A second echo signal; step 2-2: obtain a horizontal distance of an obstacle according to the first echo signal and the second echo signal, and obtain the UAV relative to a ground according to the second echo signal a height difference; step 2-3: judging whether the horizontal distance and/or the height difference conforms to a slope terrain condition; and step 2-4: when the slope terrain condition is met, adjust the UAV’s position according to a spatial information A flight trajectory, wherein the spatial information includes at least the horizontal distance and/or the altitude difference; wherein the non-rotating radar module includes at least one forward-looking radar for detecting the first echo signal and one for detecting the second echo signal Wave signal ground-following radar, the forward-looking radar has vertical height identification capability. The method of claim 7, wherein the forward-looking radar includes a short-range antenna and a long-range antenna. The method as claimed in claim 8, wherein the short-distance antenna has a detection range within 100m, and the long-distance antenna has a detection range between 50m and 300m. The method as described in claim 8, wherein in step 2-2, obtaining the horizontal distance includes the following steps: using a long-distance echo signal detected by the long-distance antenna to obtain a first distance of the obstacle relative to the UAV A relative distance D1 and a first angle θ1, the first angle θ1 is between the obstacle and an imaginary line of the UAV and an imaginary plane; according to the following formula, the obstacle relative to the UAV is obtained. The horizontal distance: D _Ta =D1×cosθ' where θ' is the addition between the first angle θ1 and a pitch angle of the drone. The method as described in claim 8, wherein in step 2-2, obtaining the horizontal distance includes the following steps: using a short-distance echo signal detected by the short-distance antenna to obtain a first distance of the obstacle relative to the UAV Two relative distances D2 and a second angle θ2, the second angle θ2 is between the obstacle and an imaginary line of the UAV and an imaginary plane; get the obstacle relative to the UAV according to the following formula The horizontal distance: D _Ta =D2×cosθ2. The method according to claim 7, wherein in step 2-4, when the slope terrain condition is met, dynamically compensate a flying height of the UAV relative to a terrain according to the spatial information. An unmanned aerial vehicle, comprising: an aircraft; and a non-rotating radar module mounted on the aircraft, the non-rotating radar module including at least one forward-looking radar and a ground-following radar, the forward-looking radar has a vertical height of Identification capability; wherein, the forward-looking radar detects at least one first echo signal in a front area, and the ground-following radar detects at least one second echo signal in a bottom area, according to the first echo signal and A spatial information of an obstacle is obtained from the second echo signal, and an early warning signal is generated when the spatial information meets an early warning condition. The drone according to claim 13, wherein the forward-looking radar includes a short-range antenna and a long-range antenna. The unmanned aerial vehicle as claimed in claim 13, wherein the non-rotating radar module is fixedly arranged on the aircraft.

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