CN-122015875-A - Low-altitude flight path planning method and platform

CN122015875ACN 122015875 ACN122015875 ACN 122015875ACN-122015875-A

Abstract

The invention belongs to the technical field of path planning, and discloses a low-altitude flight path planning method and a low-altitude flight path planning platform. The method comprises the steps of obtaining three-dimensional environment data of a target flight area and performance parameters of an aircraft, constructing an environment model, determining turning radius constraint, climbing capacity constraint and safety interval constraint, generating candidate flight paths based on the environment model, determining local flyable space ranges at all path nodes, constructing a recovery track for all path nodes, determining a feasible recovery track set according to space penetration conditions of the recovery track in the environment model, determining recovery difficulty parameters based on space safety margin change trend of the recovery track and margin change characteristics meeting the aircraft turning radius constraint and climbing capacity constraint, determining a path restorability index according to continuous accessibility of the recovery track to the safety area, and further obtaining a final optimized target flight path. The invention can improve the safety and reliability of the flight path in the complex low-altitude environment.

Inventors

XU MIN
WU HONGYU
ZHANG WENJUAN
XU HAN
ZHANG MIAO
WU LINWEI
XU QIUXIA
WU XIAOBING
YU JIE

Assignees

浙江禾记电子科技有限公司

Dates

Publication Date: 20260512
Application Date: 20260413

Claims (10)

1. A low-altitude flight path planning method is characterized by comprising the following steps of S1, obtaining three-dimensional environment data of a target flight area and performance parameters of an aircraft, constructing an environment model containing barrier space distribution information, determining turning radius constraint, climbing capacity constraint and safety interval constraint according to the performance parameters of the aircraft, S2, generating candidate flight paths formed by a plurality of path nodes according to the environment model, determining local flyable space ranges at the path nodes, S3, respectively constructing recovery tracks comprising at least one of a rollback track, a rising track and a lateral separation track for the path nodes, S4, determining a feasible recovery track set according to the spatial penetration condition of the recovery tracks in the environment model for the path nodes, determining recovery difficulty parameters in the feasible recovery track set based on the spatial safety margin change trend of the recovery tracks and margin change characteristics meeting the turning radius constraint and the climbing capacity constraint of the aircraft, determining path recoverability indexes of the path nodes according to the continuous accessibility of the recovery tracks to the preset safety area, S5, and carrying out optimization on the candidate flight paths or optimization of the target flight paths according to the recoverability indexes of the path nodes.
2. The low-altitude flight path planning method according to claim 1, wherein the method comprises the steps of generating candidate flight paths formed by a plurality of path nodes according to the environment model, determining local flyable space ranges at all the path nodes, S21, carrying out voxelization processing on the three-dimensional environment data to obtain an obstacle occupation grid, carrying out expansion processing on the obstacle occupation grid based on the safety interval constraint to obtain a flyable space grid, S22, generating an initial path according to a start point and an end point position in the flyable space grid by adopting a graph search algorithm or a sampling planning algorithm, carrying out navigation point thinning and/or smoothing processing on the initial path to obtain the candidate flight paths formed by the plurality of path nodes, and S23, aiming at any one of the candidate flight paths, taking the path node as a center, extracting a communication flyable region in a preset adjacent region, and cutting the communication flyable region by combining the turning radius constraint and the climbing capacity constraint to obtain the local flyable space ranges at the path node.
3. A low-altitude flight path planning method is characterized by comprising the steps of respectively constructing a recovery track for each path node, extracting a path segment corresponding to a preset backspacing distance along the reverse direction of the candidate flight path for any path node, superposing a braking distance determined by the flight speed and the maximum deceleration at the path node in the backspacing distance to generate a backspacing track, constructing an ascending section to a preset safe height along the height direction by taking the path node as a starting point for any path node, constructing an ascending safety body taking the safe interval constraint into consideration around the ascending section, generating an ascending track based on the collision detection result of the ascending safety body and the environment model, determining a transverse detachment direction based on the heading direction of the path node for any path node, searching a target detachment area meeting a preset wide threshold in the transverse detachment direction, and generating a lateral detachment track connecting the path node and the target detachment area under the condition of meeting the turning radius constraint.
4. A low-altitude flight path planning method according to claim 3 is characterized in that for each path node, a feasible recovery track set is determined according to the space penetration condition of the recovery track in the environment model, the method comprises the steps of S41, dispersing each recovery track into a plurality of sampling points along the track direction, constructing a local safety domain meeting the safety interval constraint at each sampling point, S42, determining the space penetration parameters of each recovery track based on the intersection relation between the local safety domain and an obstacle occupation area in the environment model, wherein the space penetration parameters comprise collision marks and continuous safety penetration lengths, S43, screening the recovery tracks according to the space penetration parameters, reserving the corresponding recovery track when the collision marks represent no collision and the continuous safety penetration lengths are not smaller than a preset penetration threshold, and S44, collecting the reserved recovery tracks to obtain the feasible recovery track set corresponding to the path node.
5. The low-altitude flight path planning method according to claim 4, wherein the method is characterized in that a recovery difficulty parameter is determined in the feasible recovery track set based on a spatial safety margin variation trend of a recovery track and margin variation characteristics meeting an aircraft turning radius constraint and a climbing capacity constraint, and a path restorability index of each path node is determined by combining continuous accessibility of the recovery track to a preset safety area, and the method comprises the steps of S45, sampling the recovery track in the feasible recovery track set along a track direction, calculating spatial safety margin at each sampling point, determining a spatial safety margin minimum value and a safety margin descending rate as spatial safety margin variation trend parameters by a spatial safety margin sequence corresponding to each recovery track, S46, calculating margin variation parameters of the recovery track meeting the turning radius constraint and the climbing capacity constraint, determining the recovery difficulty parameter corresponding to each recovery track based on the spatial safety margin variation trend parameters and the margin variation parameters corresponding to the recovery track, and determining the maximum value of each recovery track from the path node to the preset safety area based on the continuous accessibility path length of each recovery track and the corresponding recovery track parameter, and selecting the maximum value of each recovery track as the recovery path restorability index.
6. A low-altitude flight path planning platform is characterized by comprising an environment modeling module, a path generation module, a restoration track construction module and a restoration capability evaluation module, wherein the environment modeling module is used for acquiring three-dimensional environment data of a target flight area and performance parameters of an aircraft, constructing an environment model containing barrier space distribution information, determining turning radius constraint, climbing capability constraint and safety interval constraint according to the performance parameters of the aircraft, the path generation module is used for generating candidate flight paths formed by a plurality of path nodes according to the environment model, determining local flyable space ranges at the path nodes, the restoration track construction module is used for respectively constructing restoration tracks for the path nodes, the restoration tracks comprise at least one of a rollback track, a rising track and a lateral separation track, the restoration capability evaluation module is used for determining a feasible restoration track set according to the spatial penetration condition of the restoration tracks in the environment model, determining restoration difficulty parameters according to the spatial safety margin change trend of the restoration tracks and margin change characteristics meeting the turning radius constraint and the climbing capability constraint of the aircraft, determining the path restoration tracks, and optimizing the path restoration track indexes of the path candidate paths according to the path restoration track.
7. The low-altitude flight path planning platform according to claim 6, wherein the recovery track construction module is specifically configured to extract a path segment corresponding to a preset backspacing distance along a reverse direction of the candidate flight path for any path node, superimpose a braking distance determined by a flight speed and a maximum deceleration at the path node in the backspacing distance, generate a backspacing track, construct an ascending segment to a preset safe height along a height direction with the path node as a starting point for any path node, construct an ascending safety body taking the safe interval constraint into consideration around the ascending segment, generate an ascending track based on a collision detection result of the ascending safety body and the environmental model, determine a lateral detachment direction based on a heading direction of the path node for any path node, search a target detachment area meeting a preset opening degree threshold in the lateral detachment direction, and generate a lateral detachment track connecting the path node and the target detachment area under a condition that the turning radius constraint is met.
8. The low-altitude flight path planning platform according to claim 7, wherein the recovery capability assessment module is specifically configured to implement that each recovery track is discretized into a plurality of sampling points along a track direction, a local safety domain meeting the safety interval constraint is built at each sampling point, space through parameters of each recovery track are determined based on an intersection relationship between the local safety domain and an area occupied by an obstacle in the environment model, the space through parameters comprise a collision mark and a continuous safety through length, the recovery tracks are screened according to the space through parameters, when the collision mark represents no collision and the continuous safety through length is not smaller than a preset through threshold, corresponding recovery tracks are reserved, and the reserved recovery tracks are collected to obtain a feasible recovery track set corresponding to the path node.
9. The low-altitude flight path planning platform according to claim 8, wherein the recovery capability assessment module is specifically further configured to sample recovery trajectories in the feasible recovery trajectory set along a trajectory direction, calculate a space safety margin at each sampling point, determine a space safety margin minimum value and a safety margin drop rate as space safety margin variation trend parameters according to a space safety margin sequence corresponding to each recovery trajectory, calculate margin variation parameters of the recovery trajectories meeting turning radius constraints and climbing capability constraints, determine recovery difficulty parameters corresponding to each recovery trajectory based on the space safety margin variation trend parameters and the margin variation parameters corresponding to each recovery trajectory, determine a trajectory recoverability value of each recovery trajectory based on a continuous reachable path length of each recovery trajectory from the path node to a preset safety area and the corresponding recovery difficulty parameters, and select a maximum value of the trajectory recoverability values as a path recoverability index of the path node.
10. A computer readable storage medium storing a computer program, which when executed by a processor implements the method of any one of claims 1 to 5.

Description

Low-altitude flight path planning method and platform Technical Field The invention relates to the technical field of path planning, in particular to a low-altitude flight path planning method and a low-altitude flight path planning platform. Background With the increasing application of low-altitude aircrafts in urban logistics transportation, power inspection, emergency rescue, environment monitoring and other scenes, the flight path planning technology aiming at a complex low-altitude environment gradually becomes a research key point. The existing low-altitude flight path planning method is generally based on environment map information, generates a feasible path meeting space constraint and dynamic constraint through an obstacle avoidance algorithm or a graph searching algorithm, and further optimizes indexes such as path length, flight energy consumption or flight time on the basis. However, the method mainly focuses on the path trafficability of the aircraft under normal working conditions, and lacks effective consideration for sudden abnormal situations which may occur in the process of executing the path. In the actual low-altitude flight process, the aircraft may enter a local narrow area such as a building gap, a bridge lower passage, a forest corridor or a valley space, and the like, and in the area, although the path per se meets the obstacle avoidance condition, if abnormal conditions such as lock losing of a positioning signal, interruption of a communication link, sudden wind disturbance or decline of flight performance occur, the aircraft may not safely exit the current area due to limited turning radius, insufficient ascending space or insufficient lateral separation space, so that an reachable but unrecoverable risk path is formed. The existing path planning method generally does not evaluate the restorability at the path nodes, and is difficult to ensure that the aircraft still has the safety evacuation capability under the abnormal working condition, so that potential safety hazards exist in the complex low-altitude scene of the path planning result. Therefore, it is necessary to propose a low-altitude flight path planning method capable of evaluating the recovery capability of each node of the flight path in the path planning process and constraining the path generation based on the recovery capability, so as to improve the safety and the robustness of the low-altitude flight path. Disclosure of Invention In view of the above drawbacks mentioned in the background art, an object of the present invention is to provide a low-altitude flight path planning method and platform. The invention provides a low-altitude flight path planning method which comprises the following steps of S1, obtaining three-dimensional environment data of a target flight area and performance parameters of an aircraft, constructing an environment model containing barrier space distribution information, determining turning radius constraint, climbing capacity constraint and safety interval constraint according to the performance parameters of the aircraft, S2, generating candidate flight paths formed by a plurality of path nodes according to the environment model, determining local flyable space ranges at the path nodes, S3, respectively constructing recovery tracks for the path nodes, comprising at least one of a rollback track, a rising track and a lateral separation track, S4, determining a feasible recovery track set according to the space penetration condition of the recovery tracks in the environment model for the path nodes, determining recovery parameters in the feasible recovery track set based on the space safety margin change trend of the recovery tracks and margin change characteristics meeting the turning radius constraint and the climbing capacity constraint of the aircraft, determining path preset recovery indexes of the path nodes according to the continuous accessibility of the recovery tracks to the safety area, S5, and optimizing the candidate flight path or the target flight path selection indexes according to the recovery path nodes. The invention provides a low-altitude flight path planning platform, which comprises an environment modeling module, a first module, a second module and a third module, wherein the environment modeling module is used for acquiring three-dimensional environment data of a target flight area and performance parameters of an aircraft, constructing an environment model containing barrier space distribution information, and determining turning radius constraint, climbing capacity constraint and safety interval constraint according to the performance parameters of the aircraft; The system comprises an environment model, a path generation module, a restoration track construction module, a restoration capacity evaluation module and a path determination module, wherein the environment model is used for generating a candidate flight path formed by a plurality of path nodes acco