KR102636551B1 - Autonomous terrain collision avoidance apparatus and method for low-altitude operation of unmanned aerial vehicle - Google Patents

Abstract

The autonomous terrain collision avoidance device and method for low-altitude operation of an unmanned aerial vehicle (UAV) according to a preferred embodiment of the present invention continuously performs calculations for terrain collision avoidance during operation of an unmanned aerial vehicle (UAV), compared to a methodology that only applies path planning. It is possible to operate relatively close to the terrain, and the terrain avoidance point, direction, and trajectory are determined deterministically, so the operation of the system can be predicted and users can trust it.

Description

{Autonomous terrain collision avoidance apparatus and method for low-altitude operation of unmanned aerial vehicle}

The present invention relates to an autonomous terrain collision avoidance device and method for low-altitude operation of an unmanned aerial vehicle, and more specifically, to an unmanned aerial vehicle (UAV) device and method for autonomously avoiding terrain collision.

As the imaging performance of unmanned aerial vehicles (UAVs) improves and the operation duration increases, the application area for obtaining local information using small unmanned aerial vehicles (UAVs) at low altitudes is also expanding. For example, the demand for small unmanned aerial vehicles (UAVs) capable of operating below AGL (Above Ground Level) 500 m, cruising speed of 90 km/h, and operating time of less than 1 hour is increasing.

In particular, the need for low-altitude (below 500 m AGL) operation of small unmanned aerial vehicles is increasing. The conventional method uses a method of planning a route that is sufficiently separated from the terrain when planning a route. However, because the altitude margin must be set to a sufficiently large value to avoid terrain collision when planning a route, there are limitations in operating the UAV close to the terrain.

And, the demand for autonomous movement to safely move to a destination without operator manipulation or intervention is increasing. The conventional method uses a method of automatically performing a designated series of terrain collision avoidance maneuvers to avoid collisions. However, although the method of performing a predefined maneuver to avoid terrain collision is known to be the most reliable and effective terrain avoidance method, it is unknown whether the maneuver is the optimal maneuver for avoiding terrain. In addition, even if the purpose of avoiding terrain is achieved, there is no method proposed to connect the UAV with a method of guiding it to move to the desired location (destination) without operator intervention.

Additionally, the need for the ability to safely change the route on its own to meet the purpose of obtaining information, rather than just following a predetermined route, is increasing. Conventional methods use sensors such as LIDAR or video to scan obstacles, including terrain, and avoid collisions. However, the method of applying sensors such as LIDAR or video is the method that allows the drone to fly closest to the terrain, but cannot be applied to unmanned aerial vehicles that do not have the corresponding sensors. When an unmanned aerial vehicle is modified to be equipped with lidar or sensors, the operational time is reduced due to the increase in the weight of the unmanned aerial vehicle, thereby reducing the utility of the unmanned aerial vehicle.

Accordingly, there is a need for a system to safely operate unmanned aerial vehicles at low altitudes.

The purpose of the present invention is to provide an autonomous terrain collision avoidance device and method for low-altitude operation of an unmanned aerial vehicle (UAV), which allows the unmanned aerial vehicle (UAV) to fly while autonomously avoiding terrain collisions.

Other unspecified objects of the present invention can be additionally considered within the scope that can be easily inferred from the following detailed description and its effects.

In order to achieve the above object, an autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention includes an avoidance parameter setting unit that sets terrain collision avoidance parameters; Generating a plurality of avoidance trajectories based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameters, and acquiring terrain altitude information corresponding to each of the plurality of avoidance trajectories based on the plurality of avoidance trajectories and the terrain collision avoidance parameters; , an avoidance trajectory prediction unit that outputs the plurality of avoidance trajectories and the terrain altitude information corresponding to each of the plurality of avoidance trajectories; A terrain collision resolution unit that generates a terrain collision avoidance command based on the terrain collision avoidance parameter using the terrain of the last avoidance trajectory where a terrain collision is detected among the plurality of avoidance trajectories as a constraint condition, and outputs the terrain collision avoidance command. ; a path planning unit that generates a local route based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameters, and outputs the local route; and the terrain collision avoidance parameters, the plurality of avoidance trajectories output through the avoidance trajectory prediction unit, and the terrain altitude information corresponding to each of the plurality of avoidance trajectories, the terrain collision avoidance command output through the terrain collision resolution unit, and and a terrain collision avoidance control unit that provides a control command to the UAV to allow the UAV to fly while avoiding terrain collision, based on the local route output through the path planning unit.

Here, the terrain collision avoidance parameters include terrain collision avoidance policy information, unmanned aerial vehicle characteristic information, and numerical terrain elevation information, and the terrain collision avoidance policy information includes maneuvering reference information, avoidance trajectory clearance information, altitude avoidance distance information, It includes numerical terrain elevation buffer information, terrain collision avoidance reference altitude information, route plan application option information, terrain collision avoidance backup option information, terrain collision prediction section information, mission area information, and area of interest information, and the unmanned aerial vehicle characteristic information is the mission. It includes flight speed range information, bank angle information, and maximum operating altitude information, and the digital terrain elevation information may include digital terrain elevation data (DTED).

Here, the avoidance trajectory prediction unit acquires a basic avoidance trajectory corresponding to each of a plurality of maneuvers according to the maneuver reference information based on the current location of the unmanned aerial vehicle and the terrain collision prediction section information, and corresponds to each of the plurality of maneuvers. Based on the basic evasion trajectory and the evasion trajectory clearance information, a left evasion trajectory and a right evasion trajectory are obtained for each of the plurality of maneuvers, and the basic evasion trajectory, the left evasion trajectory, and the The plurality of avoidance trajectories including a right avoidance trajectory may be generated, and the terrain altitude information corresponding to each of the plurality of avoidance trajectories may be obtained based on the numerical terrain elevation data.

Here, the avoidance trajectory prediction unit obtains an initial position by adding the numerical terrain elevation buffer information from the current position of the unmanned aerial vehicle in the heading direction of the unmanned aerial vehicle, and performs a maneuver during the terrain collision prediction section information at the initial position. Obtain the basic avoidance trajectory corresponding to the maneuver by calculating the latitude, warning, and altitude for each preset time step, and based on the basic avoidance trajectory, the avoidance trajectory clearance information is 90 degrees to the left of the heading direction. The left avoidance trajectory can be obtained by calculating the falling trajectory, and the right avoidance trajectory can be obtained by calculating the trajectory away from the basic avoidance trajectory as much as the avoidance trajectory clearance information in the right direction 90 degrees based on the heading direction. there is.

Here, the terrain collision resolution unit receives the terrain collision avoidance control unit from the terrain collision avoidance control unit for which the terrain collision was last detected among the plurality of avoidance trajectories, and uses the terrain of the avoidance trajectory where the terrain collision was last detected to determine the initial terrain constraint condition. As a value, the performance index during the terrain collision prediction section information is repeatedly calculated based on the terrain constraints, UAV 3-DOF (degree of freedom) motion constraints, UAV state constraints, and control command constraints. An optimal control command set that minimizes the performance index is obtained by calculating, and when repeatedly calculating the performance index, the topography of the predicted maneuver trajectory obtained based on the control command set obtained in the immediately preceding step is used to determine the current step. Terrain constraints may be obtained, and the terrain collision avoidance command may be generated including the optimal control command set that minimizes the performance index.

Here, the terrain conflict resolution unit generates the terrain constraints by acquiring the terrain altitude corresponding to the trajectory based on the digital terrain elevation data, and determines the location of the unmanned aerial vehicle in the ENU (East-North-Up) coordinate system, the unmanned aerial vehicle. Based on the heading value, the flight path angle of the unmanned aerial vehicle, the speed of the unmanned aerial vehicle, the heading change rate, and the flight path angle change rate, the unmanned aerial vehicle 3-DOF (degree of freedom) motion constraints are generated, and the unmanned aerial vehicle's ENU (East- North-Up) Creates the UAV state constraints based on the location on the coordinate system, the terrain altitude corresponding to the location of the UAV, and the altitude avoidance distance information, and the heading change rate, the preset maximum heading change rate, and the flight path angle change rate. and generate the control command constraint based on a preset maximum flight path angle change rate, and generate the heading based on the terrain constraint, the unmanned aerial vehicle 3-DOF motion constraint, the unmanned aerial vehicle state constraint, and the control command constraint. The performance indicator consisting of a weight for control effort of the rate of change, the heading change rate, the maximum heading change rate, the weight for the control effort of the flight path angle change rate, the flight path angle change rate, and the maximum flight path angle change rate. Through, an optimal control command set including the heading change rate and the flight path angle change rate can be obtained.

Here, the path planning unit acquires as a starting point a position moved from the current location of the unmanned aerial vehicle in the heading direction of the unmanned aerial vehicle for a preset time, based on the current location of the unmanned aerial vehicle, the mission area information, and the area of interest information. The next point to which the unmanned aerial vehicle must move is obtained as the destination point, and the smaller value of the current altitude of the unmanned aerial vehicle minus the preset altitude and the maximum operating altitude information is designated as an area that cannot be moved in the digital terrain elevation data, and , the local route may be generated according to the route plan application option information based on the starting point, the destination point, and the digital terrain elevation data.

Here, the path planning unit, if the path plan application option information is a PSO (particle swarm optimization) technique, a cost function to find the shortest path for the unmanned aerial vehicle to move from the starting point to the destination point while maintaining the current altitude of the unmanned aerial vehicle. The local route is generated through, and if the route planning application option information is a grid-based heuristic route planning technique, it is set to be able to move in four directions, up, down, left, and right based on the grid of the starting point, so that the Manhattan distance is minimum. The local route can be created through a cost function that finds a route that becomes .

Here, the terrain collision avoidance control unit provides a control command to the unmanned aerial vehicle to cause the unmanned aerial vehicle to follow the local path output through the path planning unit, and the terrain collision avoidance parameter based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameter. Using the plurality of avoidance trajectories output through the avoidance trajectory prediction unit and the terrain altitude information corresponding to each of the plurality of avoidance trajectories, it is confirmed whether all of the plurality of avoidance trajectories collide with the terrain, and the plurality of avoidance trajectories are used. When all of the terrain collides with the terrain, a control command generated based on one of the terrain collision avoidance command output through the terrain collision resolution unit and a maneuver corresponding to the avoidance trajectory in which the terrain collision was last detected among the plurality of avoidance trajectories. is provided to the unmanned aerial vehicle, and when terrain collision is avoided, a control command that causes the unmanned aerial vehicle to follow the local path output through the path planning unit may be provided to the unmanned aerial vehicle.

Here, when the terrain collision avoidance control unit fails to output the terrain collision avoidance command or the terrain collision avoidance backup option information is activated, the terrain collision avoidance control unit detects the last terrain collision among the plurality of avoidance trajectories. A control command is provided to the unmanned aerial vehicle to cause the unmanned aerial vehicle to perform a maneuver corresponding to the trajectory until terrain collision avoidance is completed, and the terrain collision resolution unit outputs the terrain collision avoidance command or provides the terrain collision avoidance backup option information. When deactivated, a control command that causes the unmanned aerial vehicle to perform the terrain collision avoidance command output through the terrain collision resolution unit until terrain collision avoidance is completed may be provided to the unmanned aerial vehicle.

An autonomous terrain collision avoidance method for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention to achieve the above object is an autonomous terrain collision avoidance method performed by an autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle, generating a local route based on the current location of the unmanned aerial vehicle and terrain collision avoidance parameters; providing a control command to the unmanned aerial vehicle (UAV) to cause the unmanned aerial vehicle to follow the local route; Generate a plurality of avoidance trajectories based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameters, and obtain terrain altitude information corresponding to each of the plurality of avoidance trajectories based on the plurality of avoidance trajectories and the terrain collision avoidance parameters. steps; Confirming whether all of the plurality of avoidance trajectories collide with terrain using the plurality of avoidance trajectories and the terrain altitude information corresponding to each of the plurality of avoidance trajectories; When all of the plurality of avoidance trajectories collide with terrain, generating a terrain collision avoidance command based on the terrain collision avoidance parameter using the terrain of the last avoidance trajectory where terrain collision was detected among the plurality of avoidance trajectories as a constraint condition. step; When all of the plurality of avoidance trajectories collide with terrain, the unmanned aerial vehicle performs a control command generated based on one of the terrain collision avoidance command and a maneuver corresponding to the last avoidance trajectory for which the terrain collision is detected among the plurality of avoidance trajectories. Steps provided to; and providing a control command to the unmanned aerial vehicle (UAV) to cause the unmanned aerial vehicle to follow the local path when terrain collision is avoided.

Here, the terrain collision avoidance parameters include terrain collision avoidance policy information, unmanned aerial vehicle characteristic information, and numerical terrain elevation information, and the terrain collision avoidance policy information includes maneuvering reference information, avoidance trajectory clearance information, altitude avoidance distance information, It includes numerical terrain elevation buffer information, terrain collision avoidance reference altitude information, route plan application option information, terrain collision avoidance backup option information, terrain collision prediction section information, mission area information, and area of interest information, and the unmanned aerial vehicle characteristic information is the mission. It includes flight speed range information, bank angle information, and maximum operating altitude information, and the digital terrain elevation information may include digital terrain elevation data (DTED).

A computer program according to a preferred embodiment of the present invention for achieving the above technical problem is stored in a computer-readable recording medium and executes on the computer any one of the autonomous terrain collision avoidance methods for low-altitude operation of the unmanned aerial vehicle. .

According to the autonomous terrain collision avoidance device and method for low-altitude operation of an unmanned aerial vehicle (UAV) according to a preferred embodiment of the present invention, a methodology that only applies path planning by continuously performing calculations for terrain collision avoidance during operation of an unmanned aerial vehicle (UAV) It is possible to operate relatively close to the terrain. Additionally, because the terrain avoidance point, direction, and trajectory are determined deterministically, the operation of the system can be predicted and users can trust it. And, in the process of avoiding terrain collisions, an optimal avoidance path can be created.

In addition, because the unmanned aerial vehicle can autonomously plan a safe route to move to the destination after avoiding terrain collisions, the operator's workload can be reduced by reducing or eliminating the operator's intervention and manipulation.

In addition, since only digital terrain elevation data (DTED) and algorithms are used to secure terrain collision avoidance function, there is no need to install additional equipment such as LIDAR. And, because the weight of the unmanned aerial vehicle does not increase due to the terrain collision avoidance function, it does not affect the unmanned aerial vehicle operating time.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those skilled in the art from the description below.

1 is a block diagram illustrating an autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention.
FIG. 2 is a diagram for explaining the detailed configuration of the autonomous terrain collision avoidance device shown in FIG. 1.
FIG. 3 is a diagram for explaining the operation of the avoidance parameter setting unit shown in FIG. 2.
FIG. 4 is a diagram for explaining the operation of the avoidance trajectory prediction unit shown in FIG. 2.
FIG. 5 is a diagram for explaining the operation of acquiring the left and right avoidance trajectories shown in FIG. 4.
FIG. 6 is a diagram for explaining the operation of the terrain collision resolution unit shown in FIG. 2.
FIG. 7 is a diagram for explaining the operation of the path planning unit shown in FIG. 2.
FIG. 8 is a diagram for explaining the operation of the terrain collision avoidance control unit shown in FIG. 2.
Figure 9 is a flowchart illustrating an autonomous terrain collision avoidance method for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The advantages and features of the present invention and methods for achieving them will become clear by referring to the embodiments described in detail below along with the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below and may be implemented in various different forms. The present embodiments are merely intended to ensure that the disclosure of the present invention is complete, and that the present invention is not limited to the embodiments disclosed below and is provided by those skilled in the art It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Unless otherwise defined, all terms (including technical and scientific terms) used in this specification may be used with meanings that can be commonly understood by those skilled in the art to which the present invention pertains. Additionally, terms defined in commonly used dictionaries are not interpreted ideally or excessively unless clearly specifically defined.

In this specification, terms such as “first” and “second” are used to distinguish one component from another component, and the scope of rights should not be limited by these terms. For example, a first component may be named a second component, and similarly, the second component may also be named a first component.

In this specification, identification codes (e.g., a, b, c, etc.) for each step are used for convenience of explanation. The identification codes do not describe the order of each step, and each step is clearly understood in the context. Unless a specific order is specified, it may occur differently from the specified order. That is, each step may occur in the same order as specified, may be performed substantially simultaneously, or may be performed in the opposite order.

In this specification, expressions such as “have,” “may have,” “includes,” or “may include” indicate the presence of the corresponding feature (e.g., a numerical value, function, operation, or component such as a part). indicates, does not rule out the presence of additional features.

Additionally, the term '~unit' used in this specification refers to software or hardware components such as FPGA (field-programmable gate array) or ASIC, and the '~unit' performs certain roles. However, '~part' is not limited to software or hardware. The '~ part' may be configured to reside in an addressable storage medium and may be configured to reproduce on one or more processors. Therefore, as an example, '~ part' refers to components such as software components, object-oriented software components, class components, and task components, processes, functions, properties, and procedures. , subroutines, segments of program code, drivers, firmware, microcode, circuits, data structures, and variables. The functions provided within the components and 'parts' may be combined into a smaller number of components and 'parts' or may be further separated into additional components and 'parts'.

Hereinafter, a preferred embodiment of an autonomous terrain collision avoidance device and method for low-altitude operation of an unmanned aerial vehicle according to the present invention will be described in detail with reference to the attached drawings.

First, with reference to FIG. 1, an autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention will be described.

1 is a block diagram illustrating an autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention.

Referring to FIG. 1, an autonomous terrain collision avoidance device (hereinafter referred to as 'autonomous terrain collision avoidance device') 100 for low-altitude operation of an unmanned aerial vehicle (UAV) according to a preferred embodiment of the present invention is an unmanned aerial vehicle (UAV) ( 200) can be made to fly while autonomously avoiding terrain collisions.

That is, the autonomous terrain collision avoidance device 100 may provide a control command to control the unmanned aerial vehicle 200 to the unmanned aerial vehicle 200.

Additionally, the autonomous terrain collision avoidance device 100 may receive status information indicating the current state of the unmanned aerial vehicle (200) from the unmanned aerial vehicle (200). At this time, the unmanned aerial vehicle 200 provides its own status information to the autonomous terrain collision avoidance device 100 in units of preset cycles, or provides its own status information when a request is received from the autonomous terrain collision avoidance device 100. It can be provided as an autonomous terrain collision avoidance device 100.

Then, with reference to FIGS. 2 to 8 , the autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention will be described in more detail.

FIG. 2 is a diagram for explaining the detailed configuration of the autonomous terrain collision avoidance device shown in FIG. 1, FIG. 3 is a diagram for explaining the operation of the avoidance parameter setting unit shown in FIG. 2, and FIG. 4 is shown in FIG. 2. This is a diagram for explaining the operation of an avoidance trajectory prediction unit, FIG. 5 is a diagram for explaining the operation for acquiring the left avoidance trajectory and the right avoidance trajectory shown in FIG. 4, and FIG. 6 is a diagram for terrain collision resolution shown in FIG. 2. FIG. 7 is a diagram for explaining the operation of the path planning unit shown in FIG. 2, and FIG. 8 is a drawing for explaining the operation of the terrain collision avoidance control unit shown in FIG. 2.

Referring to FIG. 2, the autonomous terrain collision avoidance device 100 includes an avoidance parameter setting unit 110, an avoidance trajectory prediction unit 120, a terrain collision resolution unit 130, a path planning unit 140, and a terrain collision avoidance control unit. It may include (150).

The avoidance parameter setting unit 110 may set terrain collision avoidance parameters input through operator manipulation.

Here, the terrain collision avoidance parameter includes terrain collision avoidance policy information, which is a parameter used to perform terrain collision avoidance operation, unmanned aerial vehicle characteristic information, which is a parameter for the unmanned aerial vehicle 200, and numerical terrain elevation information indicating information about the altitude of the terrain. It can be included.

In other words, the terrain collision avoidance policy information includes maneuvering standard information (e.g., bank angle and flight path angle change rate for each maneuver, etc.), avoidance trajectory margin information (d _buffer ) (e.g., 50 m or more), and altitude avoidance distance information (r _threshold) . ) (e.g., more than 50 m, etc.), digital terrain elevation buffer information (e.g., more than 30 m, etc.), terrain collision avoidance reference altitude information (e.g., more than 30 m, etc.), route planning application option information (e.g., PSO technique, grid-based heuristic) path planning technique, etc.), terrain collision avoidance backup option information (e.g., activation or deactivation), terrain collision prediction interval information (t _f ) (e.g., 40 seconds, etc.), mission area information (e.g., four vertices constituting the area) Coordinates (latitude, longitude, etc.) and area of interest information (e.g., coordinates of the area of interest, order of areas of interest, etc.) may be included.

In addition, the UAV characteristic information may include mission flight speed range information (e.g., 80 km/h to 100 km/h, etc.), bank angle information (e.g., ±45°, etc.), and maximum operating altitude information (e.g., 500 m, etc.). there is.

Additionally, the digital terrain elevation information may include digital terrain elevation data (DTED).

Referring to FIG. 3 again, the avoidance parameter setting unit 110 may receive terrain collision avoidance parameters through operator manipulation.

Then, the avoidance parameter setting unit 110 can confirm the validity of the input terrain collision avoidance parameter. That is, the avoidance parameter setting unit 110 can check whether the input terrain collision avoidance parameter value is a valid value. For example, if there is no digital terrain elevation data (DTED) corresponding to the location set as the mission area information and the area of interest information, the digital terrain elevation information may be identified as invalid. If the value of the input terrain collision avoidance parameter is invalid, the avoidance parameter setting unit 110 displays information about this (reason for invalidity, etc.) and can re-enter the terrain collision avoidance parameter through operator manipulation. .

Then, the avoidance parameter setting unit 110 may check the boundary value of the input terrain collision avoidance parameter. That is, the avoidance parameter setting unit 110 can check whether the value of the input terrain collision avoidance parameter is within a preset range. For example, if the operating speed during the mission of the unmanned aerial vehicle (200) is input as "60 km/h ~ 120 km/h", it can be identified as being outside the range (80 km/h ~ 100 km/h) according to the mission flight speed range information, which is the corresponding parameter. You can. If the value of the input terrain collision avoidance parameter is not within a preset range, the avoidance parameter setting unit 110 displays information about it (boundary value range, etc.), and re-enters the terrain collision avoidance parameter through operator manipulation. You can receive it.

Then, the avoidance parameter setting unit 110 may store the input terrain collision avoidance parameters.

The avoidance trajectory prediction unit 120 generates a plurality of avoidance trajectories based on the current location and terrain collision avoidance parameters of the unmanned aerial vehicle 200 under the control of the terrain collision avoidance control unit 150, and generates a plurality of avoidance trajectories and terrain collision avoidance parameters. Based on the avoidance parameters, terrain altitude information corresponding to each of the plurality of avoidance trajectories is acquired, and the plurality of avoidance trajectories and terrain altitude information corresponding to each of the plurality of avoidance trajectories can be output.

Referring to FIG. 4 again, the avoidance trajectory prediction unit 120 may generate a plurality of avoidance trajectories and perform initialization to obtain terrain altitude information.

Then, the avoidance trajectory prediction unit 120 may obtain a basic avoidance trajectory corresponding to each of a plurality of maneuvers according to the maneuver reference information based on the current location of the unmanned aerial vehicle 200 and terrain collision prediction section information. For example, the avoidance trajectory prediction unit 120 obtains the initial position by adding the numerical terrain elevation buffer information from the current position of the unmanned aerial vehicle 200 to the heading direction of the unmanned aerial vehicle 200, and performs a maneuver during the terrain collision prediction section information at the initial position. When performing a maneuver, a basic avoidance trajectory corresponding to the maneuver can be obtained by calculating the latitude, warning, and altitude for each preset time step.

Then, the avoidance trajectory prediction unit 120 may obtain a left avoidance trajectory and a right avoidance trajectory for each of the plurality of maneuvers based on the basic avoidance trajectory and avoidance trajectory margin information corresponding to each of the plurality of maneuvers. For example, based on the basic avoidance trajectory, the avoidance trajectory prediction unit 120 may obtain a left avoidance trajectory by calculating a trajectory that is 90 degrees to the left of the heading direction by the amount of avoidance trajectory clearance information. And, based on the basic avoidance trajectory, the avoidance trajectory prediction unit 120 may obtain a right avoidance trajectory by calculating a trajectory 90 degrees to the right of the heading direction by the amount of avoidance trajectory margin information.

Then, the avoidance trajectory prediction unit 120 provides terrain altitude information corresponding to each of the plurality of avoidance trajectories, including the basic avoidance trajectory, the left avoidance trajectory, and the right avoidance trajectory for each of the plurality of maneuvers, based on the numerical terrain elevation data. can be obtained.

Then, the avoidance trajectory prediction unit 120 may output a plurality of avoidance trajectories and terrain altitude information corresponding thereto.

For example, the avoidance trajectory prediction unit 120 may initialize the algorithm by loading a maneuver according to the maneuver reference information of the terrain collision avoidance parameter and a prediction interval (t _f seconds) according to the terrain collision prediction section information of the terrain collision avoidance parameter. . It is assumed that the maneuver according to the maneuver standard information is the three maneuvers below.

- (Maneuver 1) Maneuver to move from the current location to the next route point

- (Maneuver 2) Left upward maneuver: bank angle 40 degrees, flight path angle change rate (γ') 4m/s

- (Maneuver 3) Right upward maneuver: bank angle -40 degrees, flight path angle change rate (γ') 4m/s

Set the initial position as the value added by the digital terrain elevation buffer information from the current position to the heading direction. Then, when Maneuver 1, Maneuver 2, and Maneuver 3 are performed from the initial position during the prediction interval (t _f seconds), the latitude, longitude, and altitude are calculated for each time step.

As shown in Figure 5, the ith point of the basic avoidance trajectory of maneuver 1 is denoted as P _{1i_center} . P _{1i_left} and P _{1i_right} are calculated for the prediction interval (t _f seconds), including avoidance trajectory margin information (d _buffer ). In other words, based on the basic avoidance trajectory (P _{1i_center} ), the left avoidance trajectory (P _{1i_left} ) is obtained by calculating the trajectory that is 90 degrees to the left of the heading direction by the amount of avoidance trajectory margin information (d _buffer ). And, based on the basic avoidance trajectory (P _{1i_center} ), obtain the right avoidance trajectory (P _{1i_right} ) by calculating the trajectory that is 90 degrees to the right of the heading direction by the amount of avoidance trajectory margin information (d _buffer ). can do. Maneuver 2 and Maneuver 3 are calculated in the same way.

And, multiple avoidance trajectories (P _{1i_left} , P _{1i_center} , P _{1i_right} , P _{2i_left} , P _{2i_center, P 2i_right} , P _{3i_left} , _{P 3i_center ,} P _{3i_ Right} ) Load terrain elevation information (e.g., DTED elevation) for each and every i.

In addition, a plurality of avoidance trajectories as shown below and terrain altitude information corresponding thereto can be output.

- DTED altitude values corresponding to the P _{1i_center} trajectory and the P _{1i_left} , P _{1i_center} , and P _{1i_right} trajectories for Maneuver 1

- DTED altitude values corresponding to the P _{2i_center} trajectory and the P _{2i_left} , P _{2i_center} , and P _{2i_right} trajectories for maneuver 2

- DTED altitude values corresponding to the P _{3i_center} trajectory and the P _{3i_left} , P _{3i_center} , and P _{3i_right} trajectories for maneuver 3

Under the control of the terrain collision avoidance control unit 150, the terrain collision resolution unit 130 uses the terrain of the last avoidance trajectory where the terrain collision is detected among the plurality of avoidance trajectories as a constraint and determines the terrain collision based on the terrain collision avoidance parameter. You can create avoidance commands and output terrain collision avoidance commands.

Referring to FIG. 6 again, the terrain collision resolution unit 130 may perform initialization to obtain a terrain collision avoidance command.

Then, the terrain conflict resolution unit 130 can set terrain constraints. That is, the terrain collision resolution unit 130 acquires the terrain altitude corresponding to the trajectory based on the digital terrain elevation data and establishes terrain constraints for the unmanned aerial vehicle (200) to fly during the terrain collision prediction section information (t _f ) at the current time. can be created. At this time, the terrain collision resolution unit 130 receives the terrain collision avoidance control unit 150 from the terrain collision avoidance control unit 150 with the avoidance trajectory in which the terrain collision was last detected among the plurality of avoidance trajectories, and the terrain of the avoidance trajectory in which the terrain collision was last detected is subject to terrain constraints. It can be set as the initial value of the condition. Additionally, when repeatedly calculating the performance index, the terrain conflict resolution unit 130 may obtain the terrain constraints of the current stage through the terrain of the predicted maneuver trajectory obtained based on the control command set obtained in the immediately preceding stage.

Additionally, the terrain collision resolution unit 130 may set the unmanned aerial vehicle 3-DOF (degree of freedom) movement constraint conditions. That is, the terrain collision resolution unit 130 stores the position of the unmanned aerial vehicle (200) in the ENU (East-North-Up) coordinate system, the heading value of the unmanned aerial vehicle (200), the flight path angle of the unmanned aerial vehicle (200), and the speed of the unmanned aerial vehicle (200). , Based on the heading change rate and flight path angle change rate, UAV 3-DOF (degree of freedom) motion constraints can be created as shown in [Equation 1] below.

Here, x is (x,y,z,ψ,γ) ^T. (x,y,z) indicates the location of the unmanned aerial vehicle (200) on the ENU (East-North-Up) coordinate system. ψ represents the heading value. γ represents the flight path angle. v represents the speed of the unmanned aerial vehicle (200). u ₁ represents the heading change rate. u ₂ represents the flight path angle change rate.

Additionally, the terrain collision resolution unit 130 may set a UAV state constraint condition indicating a distance constraint condition between the UAV 200 and the terrain. That is, the terrain collision resolution unit 130 uses the [mathematics below] based on the location of the unmanned aerial vehicle (200) in the ENU (East-North-Up) coordinate system, the terrain altitude and altitude avoidance distance information corresponding to the location of the unmanned aerial vehicle (200). UAV state constraints such as [Equation 2] can be created.

Here, x represents the location of the unmanned aerial vehicle 200 on the ENU (East-North-Up) coordinate system. x _terrain represents the DTED altitude value at the location of the UAV (200). r _threshold represents altitude avoidance distance information.

Additionally, the terrain conflict resolution unit 130 may set control command constraints. That is, the terrain collision resolution unit 130 generates control command constraints as shown in [Equation 3] below based on the heading change rate, the preset maximum heading change rate, the flight path angle change rate, and the preset maximum flight path angle change rate. You can.

Here, Ψ' represents the control command heading change rate. Ψ' _max represents the preset maximum heading change rate. γ' represents the control command flight path angle change rate. γ' _max represents the preset maximum flight path angle change rate.

Then, the terrain collision resolution unit 130 may calculate a performance index. That is, the terrain collision resolution unit 130 determines the weight for the control effort of the heading change rate, the heading change rate, based on the terrain constraints, UAV 3-DOF movement constraints, UAV state constraints, and control command constraints. The heading change rate and the flight path angle change rate are calculated through performance indicators such as [Equation 4] below, which consists of the maximum heading change rate, the weight for the control effort of the flight path angle change rate, the flight path angle change rate, and the maximum flight path angle change rate. An optimal control command set can be obtained.

Here, J represents the performance index. r ₁ represents the weight for the control effort of the heading change rate. r ₂ represents the weight for the control effort of the flight path angle change rate.

Then, the terrain collision resolution unit 130 may repeatedly perform constraint setting and performance index calculation to generate a terrain collision avoidance command that includes an optimal control command set that minimizes the performance index. That is, the terrain collision resolution unit 130 repeatedly calculates the performance index during the terrain collision prediction section information based on the terrain constraints, UAV 3-DOF motion constraints, UAV state constraints, and control command constraints to determine the performance index. The optimal control command set that minimizes can be obtained. Additionally, the terrain collision resolution unit 130 may generate a terrain collision avoidance command including an optimal control command set that minimizes the performance index.

Then, the terrain collision resolution unit 130 may output a terrain collision avoidance command.

The path planning unit 140 may generate a local route based on the current location of the unmanned aerial vehicle 200 and the terrain collision avoidance parameters under the control of the terrain collision avoidance control unit 150, and output the local route.

If explained again with reference to FIG. 7 , the route planning unit 140 may perform initialization to obtain a local route.

Then, the route planning unit 140 can set the starting point and destination point. That is, the path planning unit 140 may obtain as the starting point the position moved from the current location of the unmanned aerial vehicle 200 in the heading direction of the unmanned aerial vehicle 200 for a preset time (eg, 5 seconds, etc.). Additionally, the path planning unit 140 may obtain the next point to which the unmanned aerial vehicle 200 should move as the destination point based on the current location of the unmanned aerial vehicle 200, mission area information, and area of interest information.

Then, the path planning unit 140 may set an area where the unmanned aerial vehicle 200 cannot move based on the altitude of the unmanned aerial vehicle 200. That is, the path planning unit 140 may designate the smaller value of the current altitude of the unmanned aerial vehicle (200) minus the preset altitude and the maximum operating altitude information as an area where movement is not possible in the digital terrain elevation data.

Then, the route planning unit 140 may create a local route according to the route planning application option information. That is, the route planning unit 140 may generate a local route according to route planning application option information based on the starting point, destination point, and digital terrain elevation data. At this time, if the route planning application option information is a PSO (particle swarm optimization) technique, the route planning unit 140 maintains the current altitude of the unmanned aerial vehicle (200) and determines the shortest path along which the unmanned aerial vehicle (200) moves from the starting point to the destination point. A local route can be generated by finding a cost function. On the other hand, if the route planning application option information is a grid-based heuristic route planning technique, the route planning unit 140 sets the route planning unit 140 to be able to move in four directions, up, down, left, and right, based on the grid of the starting point, so that the Manhattan distance is minimized. Local routes can be generated using a route finding cost function.

Then, the route planning unit 140 can output a local route (a set of route points).

The terrain collision avoidance control unit 150 uses terrain collision avoidance parameters, a plurality of avoidance trajectories output through the avoidance trajectory prediction unit 120, terrain altitude information corresponding to each of the plurality of avoidance trajectories, and the terrain collision resolution unit 130. Based on the terrain collision avoidance command output and the local path output through the path planning unit 140, a control command that causes the unmanned aerial vehicle 200 to fly while avoiding terrain collision may be provided to the unmanned aerial vehicle 200.

Referring to FIG. 8 again, the terrain collision avoidance control unit 150 may perform initialization to operate the unmanned aerial vehicle 200 while avoiding terrain collision.

Then, the terrain collision avoidance control unit 150 may provide the unmanned aerial vehicle (200) with a control command to cause the unmanned aerial vehicle (200) to follow the local path output through the path planning unit (140).

Then, the terrain collision avoidance control unit 150 can check whether all of the plurality of avoidance trajectories collide with the terrain. That is, the terrain collision avoidance control unit 150 outputs a plurality of avoidance trajectories through the avoidance trajectory prediction unit 120 based on the current location of the unmanned aerial vehicle 200 and the terrain collision avoidance parameters and the terrain corresponding to each of the plurality of avoidance trajectories. Using altitude information, it is possible to check whether all of the plurality of avoidance trajectories collide with the terrain.

When all of the plurality of avoidance trajectories collide with the terrain, the terrain collision avoidance control unit 150 outputs a terrain collision avoidance command output through the terrain collision resolution unit 130 and the last avoidance trajectory for which the terrain collision is detected among the plurality of avoidance trajectories. A control command generated based on one of the corresponding maneuvers may be provided to the unmanned aerial vehicle (200). At this time, if the terrain collision resolution unit 130 fails to output a terrain collision avoidance command or the terrain collision avoidance backup option information is activated, the terrain collision avoidance control unit 150 determines the last terrain collision detected among the plurality of avoidance trajectories. A control command that causes the unmanned aerial vehicle 200 to perform a maneuver corresponding to the avoidance trajectory until terrain collision avoidance is completed may be provided to the unmanned aerial vehicle 200. On the other hand, when the terrain collision avoidance unit 130 outputs a terrain collision avoidance command or the terrain collision avoidance backup option information is deactivated, the terrain collision avoidance control unit 150 outputs the terrain collision avoidance unit 130. A control command may be provided to the unmanned aerial vehicle (200) that causes the unmanned aerial vehicle (200) to execute the command until terrain collision avoidance is completed.

If terrain collision is avoided, the terrain collision avoidance control unit 150 may provide the unmanned aerial vehicle 200 with a control command to cause the unmanned aerial vehicle 200 to follow the local path output through the path planning unit 140.

Then, with reference to FIG. 9, an autonomous terrain collision avoidance method for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention will be described.

Figure 9 is a flowchart illustrating an autonomous terrain collision avoidance method for low-altitude operation of an unmanned aerial vehicle according to a preferred embodiment of the present invention.

Referring to FIG. 9, the autonomous terrain collision avoidance device 100 may generate a local path based on the current location of the unmanned aerial vehicle 200 and the terrain collision avoidance parameters (S110).

Then, the autonomous terrain collision avoidance device 100 may provide a control command to the unmanned aerial vehicle 200 to cause the unmanned aerial vehicle 200 to follow a local path (S120).

Then, the autonomous terrain collision avoidance device 100 may generate a plurality of avoidance trajectories and obtain terrain altitude information corresponding to each of the plurality of avoidance trajectories (S130).

That is, the autonomous terrain collision avoidance device 100 generates a plurality of avoidance trajectories based on the current location and terrain collision avoidance parameters of the unmanned aerial vehicle 200, and generates a plurality of avoidance trajectories based on the plurality of avoidance trajectories and the terrain collision avoidance parameters. Terrain elevation information corresponding to each can be obtained.

Then, the autonomous terrain collision avoidance device 100 can check whether all of the plurality of avoidance trajectories collide with the terrain (S140).

That is, the autonomous terrain collision avoidance device 100 can check whether all of the plurality of avoidance trajectories collide with the terrain using a plurality of avoidance trajectories and terrain altitude information corresponding to each of the plurality of avoidance trajectories.

If all of the plurality of avoidance trajectories do not collide with the terrain (S150-N), the autonomous terrain collision avoidance device 100 may return to step S110.

On the other hand, if all of the plurality of avoidance trajectories collide with the terrain (S150-Y), the autonomous terrain collision avoidance device 100 uses the terrain of the avoidance trajectory with the last terrain collision detected among the plurality of avoidance trajectories as a constraint to determine the terrain. A terrain collision avoidance command can be generated based on the collision avoidance parameter (S160).

Then, the autonomous terrain collision avoidance device 100 sends a control command generated based on one of the terrain collision avoidance command and a maneuver corresponding to the last terrain collision detected avoidance trajectory among the plurality of avoidance trajectories to the unmanned aerial vehicle (200). Can be provided (S170).

If the terrain collision is not avoided (S180-N), the autonomous terrain collision avoidance device 100 may return to step S160. That is, the autonomous terrain collision avoidance device 100 may perform S160 and S170 until the terrain collision is avoided.

On the other hand, if terrain collision is avoided (S180-Y), the autonomous terrain collision avoidance device 100 may return to step S110 of providing a control command to the unmanned aerial vehicle 200 to follow a local path. .

Even though all the components constituting the embodiments of the present invention described above are described as being combined or operated in combination, the present invention is not necessarily limited to these embodiments. That is, as long as it is within the scope of the purpose of the present invention, all of the components may be operated by selectively combining one or more of them. In addition, although all of the components may be implemented as a single independent hardware, a program module in which some or all of the components are selectively combined to perform some or all of the combined functions in one or more pieces of hardware. It may also be implemented as a computer program having. In addition, such a computer program can be stored in a computer readable media such as USB memory, CD disk, flash memory, etc. and read and executed by a computer, thereby implementing embodiments of the present invention. Recording media for computer programs may include magnetic recording media and optical recording media.

The above description is merely an illustrative explanation of the technical idea of the present invention, and various modifications, changes, and substitutions can be made by those skilled in the art without departing from the essential characteristics of the present invention. will be. Accordingly, the embodiments disclosed in the present invention and the attached drawings are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments and the attached drawings. . The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

100: autonomous terrain collision avoidance device,
110: avoidance parameter setting unit,
120: avoidance trajectory prediction unit,
130: terrain collision resolution unit,
140: route planning department,
150: Terrain collision avoidance control unit,
200: drone

Claims (13)

An avoidance parameter setting unit that sets terrain collision avoidance parameters;
Generating a plurality of avoidance trajectories based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameters, and acquiring terrain altitude information corresponding to each of the plurality of avoidance trajectories based on the plurality of avoidance trajectories and the terrain collision avoidance parameters; , an avoidance trajectory prediction unit that outputs the plurality of avoidance trajectories and the terrain altitude information corresponding to each of the plurality of avoidance trajectories;
A terrain collision resolution unit that generates a terrain collision avoidance command based on the terrain collision avoidance parameter using the terrain of the last avoidance trajectory where a terrain collision is detected among the plurality of avoidance trajectories as a constraint condition, and outputs the terrain collision avoidance command. ;
a path planning unit that generates a local route based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameters, and outputs the local route; and
The terrain collision avoidance parameters, the plurality of avoidance trajectories output through the avoidance trajectory prediction unit, and the terrain altitude information corresponding to each of the plurality of avoidance trajectories, the terrain collision avoidance command output through the terrain collision resolution unit, and the a terrain collision avoidance control unit that provides a control command to the unmanned aerial vehicle (UAV) to allow the unmanned aerial vehicle to fly while avoiding terrain collisions, based on the local route output through the path planning unit;
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles, including. In paragraph 1:
The terrain collision avoidance parameter is,
Contains terrain collision avoidance policy information, unmanned aerial vehicle characteristic information, and digital terrain elevation information,
The terrain collision avoidance policy information is,
Maneuvering standard information, avoidance trajectory clearance information, altitude avoidance distance information, numerical terrain elevation buffer information, terrain collision avoidance standard altitude information, route planning application option information, terrain collision avoidance backup option information, terrain collision prediction section information, mission area information and information on areas of interest,
The drone characteristic information is,
Contains mission flight speed range information, bank angle information, and maximum operating altitude information,
The digital terrain elevation information is,
Containing digital terrain elevation data (DTED),
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 2,
The avoidance trajectory prediction unit,
Based on the current location of the unmanned aerial vehicle and the terrain collision prediction section information, a basic avoidance trajectory corresponding to each of a plurality of maneuvers according to the maneuver reference information is obtained, and a basic avoidance trajectory and the avoidance trajectory corresponding to each of the plurality of maneuvers are obtained. A left avoidance trajectory and a right avoidance trajectory are obtained for each of the plurality of maneuvers based on clearance information, and the plurality of evasions include the basic avoidance trajectory, the left avoidance trajectory, and the right avoidance trajectory for each of the plurality of maneuvers. Create an avoidance trajectory for the dog,
Obtaining the terrain elevation information corresponding to each of the plurality of avoidance trajectories based on the digital terrain elevation data,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 3,
The avoidance trajectory prediction unit,
An initial position is obtained by adding the numerical terrain elevation buffer information from the current position of the unmanned aerial vehicle in the heading direction of the unmanned aerial vehicle, and a latitude for each preset time step when a maneuver is performed during the terrain collision prediction section information at the initial position, Calculate warning and altitude to obtain the basic avoidance trajectory corresponding to the maneuver,
Based on the basic evasion trajectory, the left evasion trajectory is obtained by calculating a trajectory that is as far away as the evasion trajectory margin information in a direction 90 degrees to the left of the heading direction,
Obtaining the right avoidance trajectory by calculating a trajectory that is as far away as the avoidance trajectory margin information in a direction 90 degrees to the right of the heading direction based on the basic avoidance trajectory,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 2,
The terrain collision resolution unit,
Among the plurality of avoidance trajectories, the last avoidance trajectory in which a terrain collision is detected is provided from the terrain collision avoidance control unit, and the topography of the last avoidance trajectory in which a terrain collision is detected is set as the initial value of the terrain constraint condition,
Weights for control effort, heading change rate, maximum heading change rate, and flight based on terrain constraints, drone 3-DOF (degree of freedom) motion constraints, drone state constraints, and control command constraints. An optimal control command that minimizes the performance index by repeatedly calculating the performance index consisting of the weight for the control effort of the path angle change rate, the flight path angle change rate, and the maximum flight path angle change rate during the terrain collision prediction section information. Obtaining a set,
When repeatedly calculating the performance index, the terrain constraints of the current stage are obtained through the terrain of the predicted maneuver trajectory obtained based on the control command set obtained in the immediately preceding stage,
Generating the terrain collision avoidance command comprising the optimal control command set that minimizes the performance index,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 5,
The terrain collision resolution unit,
Generating the terrain constraints by obtaining the terrain elevation corresponding to the trajectory based on the digital terrain elevation data,
The unmanned aerial vehicle 3-DOF (degree of freedom) creates movement constraints,
Generating the unmanned aerial vehicle state constraints based on the unmanned aerial vehicle's position in the ENU (East-North-Up) coordinate system, terrain altitude corresponding to the unmanned aerial vehicle's location, and the altitude avoidance distance information,
Generating the control command constraints based on the heading change rate, the preset maximum heading change rate, the flight path angle change rate, and the preset maximum flight path angle change rate,
Weight for control effort of the heading change rate, the heading change rate, and the maximum heading change rate based on the terrain constraint, the unmanned aerial vehicle 3-DOF motion constraint, the unmanned aerial vehicle state constraint, and the control command constraint. , an optimal control command set including the heading change rate and the flight path angle change rate through the performance index consisting of a weight for the control effort of the flight path angle change rate, the flight path angle change rate, and the maximum flight path angle change rate. acquiring,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 2,
The route planning department,
Obtaining a position moved from the current location of the unmanned aerial vehicle in the heading direction of the unmanned aerial vehicle for a preset time as a starting point,
Based on the current location of the unmanned aerial vehicle, the mission area information, and the interest area information, the next point to which the unmanned aerial vehicle must move is obtained as a destination point,
Designating the smaller of the value obtained by subtracting the preset altitude from the current altitude of the unmanned aerial vehicle and the maximum operating altitude information as an area that cannot be moved in the digital terrain elevation data,
Generating the local route according to the route plan application option information based on the starting point, the destination point, and the digital terrain elevation data,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 7:
The route planning department,
If the route plan application option information is a PSO (particle swarm optimization) technique, the local route is generated through a cost function that finds the shortest path for the unmanned aerial vehicle to travel from the starting point to the destination point while maintaining the current altitude of the unmanned aerial vehicle. do,
If the route planning application option information is a grid-based heuristic route planning technique, it is set to allow movement in four directions, up, down, left, and right, based on the grid of the starting point, and a cost function is used to find the route with the minimum Manhattan distance. generating the local route,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 2,
The terrain collision avoidance control unit,
Providing a control command to the unmanned aerial vehicle to cause the unmanned aerial vehicle to follow the local route output through the path planning unit,
The plurality of avoidance trajectories output through the avoidance trajectory prediction unit based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameter and the terrain altitude information corresponding to each of the plurality of avoidance trajectories are used to determine all of the plurality of avoidance trajectories. Check whether it collides with the terrain,
When all of the plurality of avoidance trajectories collide with the terrain, one of the terrain collision avoidance command output through the terrain collision resolution unit and a maneuver corresponding to the last avoidance trajectory for which the terrain collision is detected among the plurality of avoidance trajectories is performed. Provide control commands generated to the unmanned aerial vehicle,
When terrain collision is avoided, providing a control command to the unmanned aerial vehicle to cause the unmanned aerial vehicle to follow the local path output through the path planning unit,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. In paragraph 9:
The terrain collision avoidance control unit,
If the terrain collision resolution unit fails to output the terrain collision avoidance command or the terrain collision avoidance backup option information is activated, a maneuver corresponding to the last terrain collision detected avoidance trajectory among the plurality of avoidance trajectories is performed to avoid terrain collision avoidance. Provide a control command to the unmanned aerial vehicle to cause the unmanned aerial vehicle to perform until is completed,
When the terrain collision avoidance unit outputs the terrain collision avoidance command or the terrain collision avoidance backup option information is deactivated, the unmanned aerial vehicle transmits the terrain collision avoidance command output through the terrain collision resolution unit until the terrain collision avoidance is completed. Providing control commands to the unmanned aerial vehicle to perform,
Autonomous terrain collision avoidance device for low-altitude operation of unmanned aerial vehicles. An autonomous terrain collision avoidance method performed by an autonomous terrain collision avoidance device for low-altitude operation of an unmanned aerial vehicle, comprising:
generating a local route based on the current location of the unmanned aerial vehicle and terrain collision avoidance parameters;
providing a control command to the unmanned aerial vehicle (UAV) to cause the unmanned aerial vehicle to follow the local route;
Generate a plurality of avoidance trajectories based on the current location of the unmanned aerial vehicle and the terrain collision avoidance parameters, and obtain terrain altitude information corresponding to each of the plurality of avoidance trajectories based on the plurality of avoidance trajectories and the terrain collision avoidance parameters. steps;
Confirming whether all of the plurality of avoidance trajectories collide with terrain using the plurality of avoidance trajectories and the terrain altitude information corresponding to each of the plurality of avoidance trajectories;
When all of the plurality of avoidance trajectories collide with terrain, generating a terrain collision avoidance command based on the terrain collision avoidance parameter using the terrain of the last avoidance trajectory where terrain collision was detected among the plurality of avoidance trajectories as a constraint condition. step;
When all of the plurality of avoidance trajectories collide with terrain, the unmanned aerial vehicle performs a control command generated based on one of the terrain collision avoidance command and a maneuver corresponding to the last avoidance trajectory for which the terrain collision is detected among the plurality of avoidance trajectories. Steps provided to; and
If terrain collision is avoided, providing a control command to the unmanned aerial vehicle to cause the unmanned aerial vehicle to follow the local path;
Autonomous terrain collision avoidance method for low-altitude operation of unmanned aerial vehicles, including. In paragraph 11:
The terrain collision avoidance parameter is,
Contains terrain collision avoidance policy information, unmanned aerial vehicle characteristic information, and digital terrain elevation information,
The terrain collision avoidance policy information is,
Maneuvering standard information, avoidance trajectory clearance information, altitude avoidance distance information, numerical terrain elevation buffer information, terrain collision avoidance standard altitude information, route planning application option information, terrain collision avoidance backup option information, terrain collision prediction section information, mission area information and information on areas of interest,
The drone characteristic information is,
Contains mission flight speed range information, bank angle information, and maximum operating altitude information,
The digital terrain elevation information is,
Containing digital terrain elevation data (DTED),
Autonomous terrain collision avoidance method for low-altitude operation of unmanned aerial vehicles. A computer program stored in a computer-readable recording medium for executing on a computer the autonomous terrain collision avoidance method for low-altitude operation of an unmanned aerial vehicle according to claim 11 or 12.

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