A highway geographic information navigation survey method based on unmanned aerial vehicle

Abstract

The present invention discloses a method for geographical information navigation and survey of highways based on drones, which relates to the field of geographical information navigation and survey technology, including a navigation module, a data acquisition module and a signal module. According to survey needs, the drone uses a camera to photograph the highway area to be surveyed, determines the area range according to the photographed photos, and plans the path of the drone according to the range of a single photo taken by the drone, so that the flight path of the drone covers the survey range. The present invention is equipped with a navigation module that can effectively distinguish the area to be surveyed, prevents the drone from surveying other areas, thereby improving work efficiency, and can survey the geographical information of the highway area by providing a survey probe and a camera, and conveniently models the survey area through the photographed photos, so as to facilitate subsequent detailed evaluation of the highway area.

Description

Technical Field

[0001] The invention relates to the technical field of geographic information navigation and surveying, and in particular to a method for geographic information navigation and surveying of highways based on an unmanned aerial vehicle. Background Art

[0002] Topographic surveying is the process of measuring the projection and elevation of the relative position of the terrain and objects in the survey area on the horizontal plane, and drawing a topographic map according to certain marks and symbols at a specific scale. Its results are widely used in engineering construction, geological exploration, mining, urban planning, land use analysis and military and other fields. In the early days of topographic surveying, surveying instruments were mainly used for manual positioning measurement and drawing maps. With the continuous development of remote sensing technology, global positioning system technology and computer technology, topographic surveying began to use satellites and airborne surveying systems. Since then, drone aerial surveying technology has emerged and developed and grown, gradually becoming the most common topographic surveying technology at this stage. The use of drone aerial surveying technology can quickly, accurately and efficiently obtain geographic information data of the survey area, greatly improving the quality and efficiency of topographic surveying.

[0003] The defects of existing drones are:

[0004] 1. Patent document US20160223346A1 discloses a navigation system, which discloses that "the present invention relates to a navigation method and a navigation device. In the navigation method, the actual movement of the navigation device and the user of the navigation device is detected. In order to reach the specified destination, the navigation device outputs a navigation instruction. A signal reflecting the actual geometry of the surrounding environment can be transmitted to the navigation device by a device for detecting the surrounding environment. If it is recognized that the output navigation instruction is not followed, a signal reflecting the surrounding geometry is detected. Based on the difference between the actual movement and the movement specified by the instruction, an alternative navigation instruction is determined. Compared with the originally suggested navigation instruction, the alternative navigation instruction constitutes a confirmation of the direction of movement suggested by the original navigation instruction", when the existing drone collects information, the staff needs to observe the position of the drone at all times to prevent the drone from colliding with surrounding objects, causing damage to the drone;

[0005] 2. Patent document US20150300826A1 discloses a navigation system, which discloses "providing a technology for performing route guidance with high precision in the case of a type of terminal or software environment in a navigation system in which a vehicle-mounted device displays route guidance information received from a portable terminal. The navigation system includes an independent navigation sensor installed in a vehicle; a mobile terminal with GPS receives and creates and sends route guidance information of a destination; and a vehicle-mounted device that displays the route guidance information received from the mobile terminal. The vehicle-mounted device creates a corrected current position based on the current position detected by the GPS receiver and the position change information detected by the independent navigation sensor, and sends the corrected current position to the mobile terminal. The mobile terminal creates route guidance information based on the corrected current position and the map information received from the vehicle-mounted device", and when existing drones collect ground data information, most of them use shooting to shoot, resulting in incomplete information collection;

[0006] 3. Patent document JP2016532513A discloses a navigation system, which discloses "the present invention relates to a navigation system for an intervention system and a navigation system for navigating an interventional device, such as a catheter. A position and shape determination unit, during a first interventional procedure, such as a first chemoembolization session, to determine a first position and shape of a biological body, a second chemo-intervention device, during a next interventional procedure such as an embolization session to determine a second position and shape of the interventional device in the biological body. In the second interventional procedure, the interventional device is navigated based on the first position and the stored shape, and the second position and shape. This makes it possible to navigate between the second interventional procedure, taking into account the path of the interventional device used during the first interventional procedure. In particular, this is between the first and second interventional procedures, between interventional devices along the same path that can be navigated", and existing drones require manual control of the direction by staff when in use, which increases the workload of staff;

[0007] 4. Patent document CN111284694A discloses an engineering survey UAV system and survey and mapping method based on satellite positioning and navigation, which discloses "including UAV body, support arm, propeller, landing gear, transportation device, sampling device, power supply, monitoring device, workstation. The UAV body includes a navigation and positioning module, an environmental detection module, a measurement and layout module, a survey work monitoring module, a wireless communication module, a transportation module, a sampling module, a text image recognition module, a flight control module, an anti-collision protection module, a power supply module, a memory, and a lost recovery module. The present invention adopts advanced positioning and navigation technology, remote sensing imaging technology, Radar technology, flight control technology, real-time aerial photography and voice call technology, intelligent survey technology, text image recognition technology, wireless transmission technology, geotechnical engineering survey and high-tech are combined to realize many important functions such as automatic survey and setting out, coordinate elevation re-survey, drilling rig navigation reminder, survey work quality and progress correction, automatic transportation and sampling, human-computer interaction, text image automatic and UAV lost recovery. "Existing UAVs often use a slow landing method to make the UAV contact with the ground to land. During this process, the UAV blades continue to rotate and then stop, resulting in a large landing force, which will damage the UAV and is not safe enough. Summary of the invention

[0008] The purpose of the present invention is to provide a highway geographic information navigation and survey method based on unmanned aerial vehicle to solve the problems raised in the above background technology.

[0009] To achieve the above-mentioned purpose, the present invention provides the following technical solution: a method for navigation and surveying highway geographic information based on unmanned aerial vehicle, comprising a navigation module, a data acquisition module and a signal module.

[0010] Preferably, the navigation module uses GPS navigation, takes pictures of the ground through a camera, collects ground data information, and calculates the position of the drone based on the positions of the drone and surrounding base stations and the pictures taken by the drone;

[0011] According to the survey needs, the drone uses a camera to take pictures of the highway area to be surveyed, determines the area range based on the pictures taken, plans the flight path of the drone based on the range of a single picture taken by the drone, so that the flight path of the drone covers the survey range, and adjusts the flight attitude of the drone based on the flight path points. The planned three-dimensional track of the drone needs to meet basic constraints, including the maximum turning angle, the maximum climbing angle or gliding angle, the minimum track segment length, the minimum and maximum flight altitudes, and the maximum track length constraint. Among them, the maximum turning angle constraint means that the drone can only turn within a horizontal plane that is less than or equal to the specified maximum turning angle, and the maximum climbing angle or gliding angle constraint means that the drone can only climb or glide within a vertical plane that is less than or equal to the specified maximum climbing angle or gliding angle; the minimum track segment length constraint requires the drone to fly the shortest distance in the current track direction before changing its flight attitude; the minimum and maximum flight altitude constraints require the drone to fly within a specified flight altitude range; the maximum track length constraint means that the track length of the drone is less than or equal to the specified threshold;

[0012] Maximum turning angle constraint, let the maximum turning angle be θmax, the horizontal turning angle of the i-th track point qi be θi, then θi≤θmax, consider 3 consecutive track points q i-1 ,q i-2， qi(i=3,4,5....) Then, the projections of the vectors formed by the track segments qiqi-1 and qi-1qi-2 on the horizontal plane are (x i -x i-1 ,y i -y i-1 ) and (x i-1 -x i-2 ,y i-1 -y i-2 ), at this time, it can be expressed as Maximum climb angle or glide angle constraint, let the maximum climb angle or glide angle be Ψmax, the climb angle or glide angle of qi be Ψi, then Ψi is less than or equal to Ψmax, consider two consecutive track points q i-1 , qi (i = 2, 3, 4...), then the vector formed by the track segments qiqi-1 and qi-1qi-2 is (x i -x i-1 ,y i -y i-1 , z i -z i-1 ), then Ψi can be expressed as Minimum track segment length constraint, denoted by L min , the length of qiqi-1 is L i , then, L i ≥Lmin Here, L i It can be expressed as

[0013] The minimum and maximum flight altitude constraints, the minimum flight altitude is Zmin, the maximum flight altitude is Zmax, then, z min≤ z i≤ z max ;

[0014] The maximum track length constraint, let the maximum track length be Lmax, then the track is q1q2q3...qn to satisfy

[0015] The path planning of the drone uses the ant colony algorithm. The basic steps of the ant colony algorithm are simple and can be divided into the following steps:

[0016] Step 1: Initialize the relevant parameters, including the ant population m, pheromone factor parameter, city size, heuristic factor parameter, pheromone volatility factor ρ parameter, pheromone constant Q, maximum number of iterations, etc.

[0017] Step 2: All ant populations are randomly distributed in different cities, and the probability of each ant visiting the next city is calculated. The ants are allowed to visit all cities according to the taboo table.

[0018] Step 3: As the number of iterations increases, the path information of the ants is recorded, the optimal solution of the current path is recorded, the information concentration on different paths is updated, and the number of iterations is recorded;

[0019] Step 4: Determine whether the number of iterations is sufficient to continue iterating. If not, output the optimal solution. Otherwise, continue iterating.

[0020] Preferably, the data acquisition module includes a geographic information acquisition unit, a synthesis unit and a transmission unit;

[0021] The geographic information acquisition unit conducts surveys through a survey probe. The survey probe uses a laser radar to scan the ground with a laser beam to obtain terrain and object elevation information. The survey process is as follows;

[0022] Laser radar emits laser beams to scan the surrounding environment. The radar frequency is 56GHz-156GHz. The laser beam is emitted at an extremely high speed and is reflected back when it intersects with an object.

[0023] The camera takes pictures at 35-55 frames per second with a resolution of 15-35 million pixels, and the map model is synthesized from the aerial photos.

[0024] Receive reflected signals. The laser radar receives the reflected laser signals and records the distance and angle information of each reflection point.

[0025] The synthesis unit processes the received reflected signals and generates a three-dimensional point cloud map, where each point represents a scanned object or surface;

[0026] Data processing: The generated point cloud data can be further processed and analyzed to detect and identify obstacles, build environmental maps, and perform positioning and navigation. LiDAR generates point cloud data by emitting laser beams and receiving reflected signals to obtain three-dimensional information about the surrounding environment.

[0027] The transmission unit transmits the scanned geographic information data to the storage chip in the control handle through wireless signals for storage.

[0028] Preferably, the signal control module includes an instruction transmitting unit, an instruction encryption unit and an instruction receiving unit;

[0029] The command transmission unit uses the 5.8GHz frequency band to transmit wireless signals through the control handle and the corresponding control buttons;

[0030] An instruction encryption unit encrypts the transmitted instruction signal using a symmetric encryption method;

[0031] Command reception: the integrated chip on the drone receives and decrypts the signal to control the drone's flight path, flight attitude, altitude and shooting.

[0032] Preferably, the path planning method of the UAV is as follows;

[0033] The basic principle of the UAV path planning algorithm based on the potential field method is to use the gradient of the potential field to plan the path of the UAV. The potential field is the influence of the environment around the UAV on it, obstacles, and target points. In the potential field method, the target point of the UAV is regarded as an attractor, and the obstacle is regarded as a repulsion. The path planning process of the UAV is the process of finding a balance point between the attractor and the repulsion. In the potential field method, the position of the UAV is represented as (x, y), the potential field is represented as U(x, y), and the gradient of the potential field is represented as u;

[0034] u(x,y)=(U / x,U / y)

[0035] In UAV path planning, the target point is usually regarded as an attractor, and its potential field is expressed as:

[0036] U_goal(x,y)=k*((x-x_goal)^2+(y-y_goal)^2)

[0037] Where k is a constant, (x_goal, y_goal) is the coordinate of the target point;

[0038] Obstacles are usually considered as repulsors, and their potential fields are represented as;

[0039] U_obs(x,y)=∑(k_obs / d_obs-1 / d_obs^2)*f(d_obs)

[0040] Among them, k_obs is a constant, d_obs is the distance from the drone to the obstacle, and f(d_obs) is the obstacle correction function, which is usually:

[0041] ∫(d_obs)={1,d_obs>d0{(d_obs-d0)^2 / ((d_obs-d0)^2-1),d_obs<=d0

[0042] Among them, d0 is the range of the obstacle;

[0043] The displacement of the UAV in the potential field is expressed as:

[0044] Δx=-α*U(x,y)

[0045] Among them, α is the step size parameter. In the UAV path planning, it is necessary to continuously calculate the potential field around the UAV and update the position of the UAV according to the gradient of the potential field until the UAV reaches the target point.

[0046] Preferably, the operation steps of the drone are as follows:

[0047] S1. When the UAV is landing, the third distance sensor detects the distance between the UAV and the ground. When it is detected that the distance is close, the third distance sensor controls the extrusion structure to squeeze the gas inside the gas storage component, and then the gas is ejected from the jet head. At the same time, the fan blades of the UAV stop rotating, and the UAV is thrust upward after the jet head ejects the air downward, so that the UAV hovers 1-2cm above the ground. Then the jet ends, and the UAV falls due to gravity, and the landing gear contacts the ground, which cushions the UAV and realizes the cushioning protection function.

[0048] Compared with the prior art, the present invention has the following beneficial effects:

[0049] 1. The present invention can effectively distinguish the areas that need to be surveyed by providing a navigation module, preventing the drone from surveying other areas, thereby improving work efficiency;

[0050] 2. The present invention can survey the geographical information of the highway area by providing a survey probe and a camera, and can conveniently model the survey area through the photographs taken, so as to facilitate the subsequent detailed evaluation of the highway area;

[0051] 3. The present invention is designed with a path planning module to allow the drone to automatically patrol the survey area, which can reduce the workload of the staff, and by controlling the flight posture of the drone, it can automatically avoid obstacles and prevent the drone from being damaged;

[0052] 4. The present invention installs a third distance sensor to detect the distance between the UAV and the ground when the UAV is landing. When it is detected that the distance is close, the third distance sensor controls the extrusion structure to squeeze the gas inside the gas storage component, and then the gas is ejected from the jet head. At the same time, the fan blades of the UAV stop rotating, and the UAV is thrust upward after the jet head ejects the air downward, so that the UAV hovers 1-2 cm above the ground. Then the jet ends, the UAV falls due to gravity, and the landing gear contacts the ground, which cushions the UAV and realizes the cushioning protection function. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] Figure 1 It is a navigation flow chart of the present invention;

[0054] Figure 2 This is a signal encryption flow chart of the present invention. DETAILED DESCRIPTION

[0055] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0056] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "provided with", "connected", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0057] Example 1: Please refer to Figure 1 , an embodiment provided by the present invention: a data acquisition module and a signal module, wherein the navigation module adopts GPS navigation, takes pictures of the ground through a camera, collects ground data information, and calculates the position of the drone according to the positions of the drone and surrounding base stations and the pictures taken by the drone;

[0058] According to the survey needs, the drone uses a camera to take pictures of the highway area to be surveyed, determines the area range based on the pictures taken, plans the flight path of the drone based on the range of a single picture taken by the drone, so that the flight path of the drone covers the survey range, and adjusts the flight attitude of the drone based on the flight path points. The planned three-dimensional track of the drone needs to meet basic constraints, including the maximum turning angle, the maximum climbing angle or gliding angle, the minimum track segment length, the minimum and maximum flight altitudes, and the maximum track length constraint. Among them, the maximum turning angle constraint means that the drone can only turn within a horizontal plane that is less than or equal to the specified maximum turning angle, and the maximum climbing angle or gliding angle constraint means that the drone can only climb or glide within a vertical plane that is less than or equal to the specified maximum climbing angle or gliding angle; the minimum track segment length constraint requires the drone to fly the shortest distance in the current track direction before changing its flight attitude; the minimum and maximum flight altitude constraints require the drone to fly within a specified flight altitude range; the maximum track length constraint means that the track length of the drone is less than or equal to the specified threshold;

[0059] Maximum turning angle constraint, let the maximum turning angle be θmax, the horizontal turning angle of the i-th track point qi be θi, then θi≤θmax, consider 3 consecutive track points q i-1 ,q i-2， qi(i=3,4,5....) Then, the projections of the vectors formed by the track segments qiqi-1 and qi-1qi-2 on the horizontal plane are (x i -x i-1 ,y i -y i-1 ) and (x i-1 -x i-2 ,y i-1 -y i-2 ), at this time, it can be expressed as Maximum climb angle or glide angle constraint, let the maximum climb angle or glide angle be Ψmax, the climb angle or glide angle of qi be Ψi, then Ψi is less than or equal to Ψmax, consider two consecutive track points q i-1 , qi (i = 2, 3, 4...), then the vector formed by the track segments qiqi-1 and qi-1qi-2 is (x i -x i-1 ,y i -y i-1 , z i -z i-1 ), then Ψi can be expressed as Minimum track segment length constraint, denoted by L min , the length of qiqi-1 is L i , then, L i ≥Lmin， Here, L i It can be expressed as

[0060] The minimum and maximum flight altitude constraints, the minimum flight altitude is Zmin, the maximum flight altitude is Zmax, then, z min≤ z i≤ z max ;

[0061] The maximum track length constraint, let the maximum track length be Lmax, then the track is q1q2q3...qn to satisfy

[0062] Embodiment 2: The data acquisition module includes a geographic information acquisition unit, a synthesis unit and a transmission unit;

[0063] The geographic information acquisition unit conducts surveys through a survey probe. The survey probe uses a laser radar to scan the ground with a laser beam to obtain terrain and object elevation information. The survey process is as follows;

[0064] Laser radar emits laser beams to scan the surrounding environment. The radar frequency is 56GHz-156GHz. The laser beam is emitted at an extremely high speed and is reflected back when it intersects with an object.

[0065] The camera takes pictures at 35-55 frames per second with a resolution of 15-35 million pixels, and the map model is synthesized from the aerial photos.

[0066] Receive reflected signals. The laser radar receives the reflected laser signals and records the distance and angle information of each reflection point.

[0067] The synthesis unit processes the received reflected signals and generates a three-dimensional point cloud map, where each point represents a scanned object or surface;

[0068] Data processing: The generated point cloud data is further processed and analyzed to detect and identify obstacles, build environmental maps, and perform positioning and navigation. LiDAR generates point cloud data by emitting laser beams and receiving reflected signals to obtain three-dimensional information about the surrounding environment.

[0069] The transmission unit transmits the scanned geographic information data to the storage chip in the control handle through wireless signals for storage.

[0070] Example 3: Please refer to Figure 1 and Figure 2 , the signal control module includes an instruction transmitting unit, an instruction encryption unit and an instruction receiving unit;

[0071] The command transmitting unit uses the 5.8 GHz frequency band to transmit wireless signals through the control handle 16 and the corresponding control button 17;

[0072] An instruction encryption unit encrypts the transmitted instruction signal using a symmetric encryption method;

[0073] The command is received, and the integrated chip 11 on the drone receives and decrypts the signal to control the flight path, flight attitude, altitude and shooting of the drone.

[0074] Embodiment 4: The path planning method of the UAV is as follows;

[0075] The basic principle of the UAV path planning algorithm based on the potential field method is to use the gradient of the potential field to plan the path of the UAV. The potential field is the influence of the environment around the UAV on it, obstacles, and target points. In the potential field method, the target point of the UAV is regarded as an attractor, and the obstacle is regarded as a repulsion. The path planning process of the UAV is the process of finding a balance point between the attractor and the repulsion. In the potential field method, the position of the UAV is represented as (x, y), the potential field is represented as U(x, y), and the gradient of the potential field is represented as u;

[0076] u(x,y)=(U / x,U / y)

[0077] In UAV path planning, the target point is regarded as an attractor, and its potential field is expressed as:

[0078] U_goal(x,y)=k*((x-x_goal)^2+(y-y_goal)^2)

[0079] Where k is a constant, (x_goal, y_goal) is the coordinate of the target point;

[0080] The obstacle is considered as a repulsor and its potential field is expressed as;

[0081] U_obs(x,y)=∑(k_obs / d_obs-1 / d_obs^2)*f(d_obs)

[0082] Among them, k_obs is a constant, d_obs is the distance from the drone to the obstacle, and f(d_obs) is the obstacle correction function, which is:

[0083] ∫(d_obs)={1,d_obs>d0{(d_obs-d0)^2 / ((d_obs-d0)^2-1),d_obs<=d0

[0084] Among them, d0 is the range of the obstacle;

[0085] The displacement of the UAV in the potential field is expressed as:

[0086] Δx=-α*U(x,y)

[0087] Among them, α is the step size parameter. In the UAV path planning, it is necessary to continuously calculate the potential field around the UAV and update the position of the UAV according to the gradient of the potential field until the UAV reaches the target point.

[0088] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other specific forms without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered exemplary and non-limiting in all respects, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations falling within the meaning and scope of the equivalent elements of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

Claims

1. A method for surveying and navigating highway geographic information based on unmanned aerial vehicles, characterized in that: It includes a navigation module of the drone, a geographic information data collection module of the drone and a signal module of the drone. The navigation module uses GPS navigation, takes pictures of the ground through a camera, collects ground data information, and calculates the location of the drone based on the location of the drone and surrounding base stations and the pictures taken by the drone. According to the survey needs, the drone uses a camera to take photos of the highway area to be surveyed, determines the area range based on the photos taken, and plans the drone's path based on the range of a single photo taken by the drone, so that the drone's flight path covers the survey range; The data acquisition module includes a geographic information acquisition unit, a synthesis unit and a transmission unit; The geographic information acquisition unit conducts surveys through a survey probe. The survey probe uses a laser radar to scan the ground with a laser beam to obtain terrain and object elevation information. The survey process is as follows; Laser radar emits laser beams to scan the surrounding environment. The radar frequency is 56GHz-156GHz. The laser beam is emitted at an extremely high speed and is reflected back when it intersects with an object. The camera takes pictures at 35-55 frames per second with a resolution of 15-35 million pixels, and the map model is synthesized from the aerial photos. Receive reflected signals. The laser radar receives the reflected laser signals and records the distance and angle information of each reflection point. The synthesis unit processes the received reflected signals and generates a three-dimensional point cloud map, where each point represents a scanned object or surface; Data processing: The generated point cloud data is further processed and analyzed to detect and identify obstacles, build environmental maps, and perform positioning and navigation. LiDAR generates point cloud data by emitting laser beams and receiving reflected signals to obtain three-dimensional information about the surrounding environment. The transmission unit transmits the scanned geographic information data to the storage chip in the control handle through wireless signals for storage; The method for planning the path of the UAV is as follows; The basic principle of the UAV path planning algorithm based on the potential field method is to use the gradient of the potential field to plan the path of the UAV. The potential field is the influence of the environment around the UAV on it, obstacles, and target points. In the potential field method, the target point of the UAV is regarded as an attractor, and the obstacle is regarded as a repulsion. The path planning process of the UAV is the process of finding a balance point between the attractor and the repulsion. In the potential field method, the position of the drone is represented as (x, y), the potential field is represented as U(x, y), and the gradient of the potential field is represented as u; u(x,y)=(U / x,U / y) In UAV path planning, the target point is regarded as an attractor, and its potential field is expressed as: U_goal(x,y)=k·((x-x_goal)^2+(y-y_goal)^2) Where k is a constant, (x_goal, y_goal) is the coordinate of the target point; The obstacle is considered as a repulsor and its potential field is expressed as; U_obs(x,y)=∑(k_obs / d_obs-1 / d_obs^2)·f(d_obs) Among them, k_obs is a constant, d_obs is the distance from the drone to the obstacle, and f(d_obs) is the obstacle correction function, which is: , where d0 is the range of the obstacle; The displacement of the UAV in the potential field is expressed as: Δx=-α·U(x,y) Among them, α is the step size parameter. In the UAV path planning, it is necessary to continuously calculate the potential field around the UAV and update the position of the UAV according to the gradient of the potential field until the UAV reaches the target point; When the drone is landing, the third distance sensor detects the distance between the drone and the ground. When it is detected that the distance is close, the third distance sensor controls the extrusion structure to squeeze the gas inside the gas storage component, and then the gas is ejected from the jet head. At the same time, the fan blades of the drone stop rotating, and the drone is pushed upward by the jet head after the jet is ejected downward, so that the drone hovers 1-2cm above the ground. Then the jet ends, the drone falls due to gravity, and the landing gear contacts the ground, which cushions the drone and realizes the buffer protection function. The flight attitude of the drone is adjusted according to the flight path points. The planned three-dimensional track of the drone needs to meet basic constraints, including the maximum turning angle, the maximum climbing angle or the descent angle, the minimum track segment length, the minimum and maximum flight altitudes, and the maximum track length constraint. Among them, the maximum turning angle constraint means that the drone can only turn within a horizontal plane that is less than or equal to the specified maximum turning angle, and the maximum climbing angle or the descent angle constraint means that the drone can only climb or descend within a vertical plane that is less than or equal to the specified maximum climbing angle or the descent angle; the minimum track segment length constraint requires the drone to fly the shortest distance in the current track direction before changing its flight attitude, the minimum and maximum flight altitude constraints require the drone to fly within a specified flight altitude range, and the maximum track length constraint means that the drone's track length is less than or equal to the specified threshold; Maximum turning angle constraint, denoted by θ max , the i-th track point q i The horizontal turning angle is θ i , then θ i ≤θ max , consider 3 consecutive track points q i-1 ,q i-2， q i (i=3, 4, 5....) Then, the track segment q i q i-1 and q i-1 q i-2 The projections of the vectors formed on the horizontal plane are (x i -x i-1 ,y i -y i-1 ) and (x i-1 -x i-2 ,y i-1 -y i-2 ), at this time, the horizontal turning angle is expressed as ; Maximum climbing angle or gliding angle constraint, denoted as Ψ max ,q i The climbing angle or gliding angle is Ψ i , then i Less than or equal to Ψ max , consider two consecutive track points q i-1 ,q i (i=2, 3, 4...), then the track segment q i q i-1 The vector formed is (x i -x i-1 ,y i -y i-1 , z i -z i-1 ), at this time i Expressed as ; Minimum track segment length constraint, denoted by L min ,q i q i-1 The length is L i , then, L i ≥L min , here, L i Expressed as ; Minimum and maximum flight altitude constraints, with the minimum flight altitude being Z min , the maximum flight altitude is Z max , then, z min≤ z i≤ z max ; Maximum track length constraint, denoted by L max , then, the track is q1q2q3...q n satisfy .

2. The method for surveying and navigating highway geographic information based on unmanned aerial vehicles according to claim 1, characterized in that: The path planning of the drone uses the ant colony algorithm. The basic steps of the ant colony algorithm are simple and can be divided into the following steps: Step 1: Initialize relevant parameters, including ant population m, pheromone factor parameter, city size, heuristic factor parameter, pheromone volatility factor ρ parameter, pheromone constant Q and maximum number of iterations; Step 2: All ant populations are randomly distributed in different cities, the probability of each ant visiting the next city is calculated, and the ants are allowed to visit all cities according to the taboo table; Step 3: As the number of iterations increases, record the path information of the ants, record the optimal solution of the current path, update the information concentration on different paths, and record the number of iterations; Step 4: Determine whether the number of iterations meets the need to continue iterating. If not, output the optimal solution. Otherwise, continue iterating.

3. The method for surveying and navigating highway geographic information based on unmanned aerial vehicles according to claim 1, characterized in that: The signal control module includes an instruction transmitting unit, an instruction encryption unit and an instruction receiving unit; The command transmission unit uses the 5.8GHz frequency band to transmit wireless signals through the control handle and the corresponding control buttons; An instruction encryption unit encrypts the transmitted instruction signal using a symmetric encryption method; Command reception: the integrated chip on the drone receives and decrypts the signal to control the drone's flight path, flight attitude, altitude and shooting.

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