A karst cave morphology detection system and method based on laser ranging

Abstract

The present invention is applicable to the technical field of cave detection, and provides a cave morphology detection system and method based on laser ranging, comprising the following steps: receiving a coordinate system establishment command, establishing a coordinate system; receiving a drone movement instruction, obtaining a moving route, determining the coordinates of the midpoints of two laser rangefinders at this time according to the moving route, and determining the coordinates of the two laser rangefinders; receiving a ranging instruction, turning on the laser rangefinder, and causing the laser rangefinder to swing by a rangefinder driving mechanism, obtaining a swing angle and a ranging distance, and determining the coordinates of the cave wall points according to the coordinates, swing angle and ranging distance of the laser rangefinder. The present invention uses two laser rangefinders to comprehensively scan the drone up, down, left and right, and by inputting a drone movement instruction, the drone continuously moves toward the inside of the cave, thereby being able to obtain a large number of cave wall point coordinates, and the cave morphology can be determined according to all the cave wall point coordinates, and the determined cave morphology is comprehensive and accurate.

Description

Technical Field

[0001] The present invention relates to the technical field of cave detection, and in particular to a cave morphology detection system and method based on laser ranging. Background Art

[0002] The commonly used cave morphology detection methods currently include advance drilling, geophysical drilling, three-high measurement technology, etc. Most of these cave detection technologies are based on the surface and rely on vertical drilling technology to detect the caves below the surface. The above technologies have the following defects: the internal specific structure and size of the cave cannot be determined, and the complete cave detection cannot be carried out, that is, the specific morphology of the cave cannot be known in all directions. Therefore, it is necessary to provide a cave morphology detection system and method based on laser ranging to solve the above problems. Summary of the invention

[0003] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a system and method for detecting cave morphology based on laser ranging to solve the problems existing in the above-mentioned background technology.

[0004] The present invention is implemented as follows: a method for detecting cave morphology based on laser ranging, the method comprising the following steps:

[0005] Receive the coordinate system establishment command, establish the coordinate system, take the midpoint of the two laser rangefinders on the drone as the origin, set the two laser rangefinders symmetrically on the left and right, take the vertical upward direction of the origin as the Z axis, take the direction of the drone's nose as the X axis, and determine the Y axis based on the Z axis and the X axis;

[0006] The cave images were obtained through the camera installed on the drone;

[0007] Receive the UAV movement instruction, so that the UAV moves a certain distance and then pauses, obtain the movement route, determine the coordinates of the midpoints of the two laser rangefinders at this time according to the movement route, and determine the coordinates of the two laser rangefinders;

[0008] Receiving the distance measurement instruction, the laser rangefinder is turned on, and the rangefinder driving mechanism causes the laser rangefinder to swing, obtain the swing angle and the distance measurement, and determine the coordinates of the cave wall point according to the coordinates of the laser rangefinder, the swing angle and the distance measurement;

[0009] Repeat the two steps of receiving the UAV movement instruction and receiving the distance measurement instruction to obtain the coordinates of several cave wall points, and determine the cave shape according to the coordinates of the cave wall points.

[0010] As a further solution of the present invention: the steps of obtaining the moving route, determining the coordinates of the midpoints of the two laser rangefinders at this time according to the moving route, and determining the coordinates of the two laser rangefinders specifically include:

[0011] The moving route is obtained through the UAV moving instructions, and the coordinates of the midpoints of the two laser rangefinders at this time are determined according to the moving route;

[0012] Determine the direction of the drone using the magnetic compass installed on the drone;

[0013] The distance between the two laser rangefinders is retrieved, and the coordinates of the two laser rangefinders are determined according to the coordinates of the midpoints of the two laser rangefinders, the orientation of the UAV, and the distance between the two laser rangefinders.

[0014] As a further solution of the present invention: the rangefinder driving mechanism causes the laser rangefinder to swing, and the steps of obtaining the swing angle and the ranging distance specifically include:

[0015] Calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser;

[0016] The rangefinder driving mechanism makes the laser rangefinder swing a certain angle, calculates the current swing angle, emits laser, and determines the distance after receiving the reflected laser;

[0017] Repeat the previous step until the swing stroke of the laser rangefinder is completed, and obtain several ranging distances, each ranging distance corresponding to a swing angle.

[0018] As a further solution of the present invention: the step of determining the morphology of the cave according to the coordinates of the cave wall points specifically includes:

[0019] The coordinates of the cave wall points are grouped according to the cave wall points obtained from each drone movement;

[0020] The spline curve is used to fit the coordinates of the cave wall points in each group to obtain several closed curves.

[0021] As a further solution of the present invention: the step of fitting the coordinates of the cave wall points in each group with a spline curve to obtain a plurality of closed curves further includes:

[0022] The coordinates of the cave wall points are secondary grouped according to the swing angles corresponding to the coordinates of the cave wall points;

[0023] The spline curve is used to fit the coordinates of the cave wall points in each group to obtain a number of long curves. The long curves and a number of closed curves form a curve mesh surface, which can reflect the morphology of the cave.

[0024] Another object of the present invention is to provide a cave morphology detection system based on laser ranging, the system comprising:

[0025] The coordinate system establishment module is used to receive the coordinate system establishment command and establish the coordinate system. The midpoint of the two laser rangefinders on the drone is taken as the origin. The two laser rangefinders are set symmetrically on the left and right. The vertical upward direction of the origin is taken as the Z axis, and the direction of the drone's nose is taken as the X axis. The Y axis is determined according to the Z axis and the X axis.

[0026] The cave image acquisition module is used to obtain the cave image through the camera installed on the UAV;

[0027] The moving instruction receiving module is used to receive the moving instruction of the UAV, so that the UAV pauses after moving a certain distance, obtains the moving route, determines the coordinates of the midpoints of the two laser rangefinders at this time according to the moving route, and determines the coordinates of the two laser rangefinders;

[0028] The distance measurement instruction receiving module is used to receive the distance measurement instruction, the laser distance meter is turned on, and the distance meter driving mechanism causes the laser distance meter to swing, obtains the swing angle and the distance measurement, and determines the coordinates of the cave wall point according to the coordinates of the laser distance meter, the swing angle and the distance measurement;

[0029] The cave morphology determination module is used to repeat the two steps of receiving the UAV movement instruction and receiving the distance measurement instruction to obtain the coordinates of several cave wall points and determine the cave morphology according to the coordinates of the cave wall points.

[0030] As a further solution of the present invention: the movement instruction receiving module includes:

[0031] A midpoint coordinate determination unit is used to obtain a moving route through a UAV moving instruction, and determine the coordinates of the midpoints of the two laser rangefinders at this time according to the moving route;

[0032] A drone heading unit, used to determine the heading of the drone through a magnetic compass installed on the drone;

[0033] The rangefinder coordinate unit is used to retrieve the distance between the two laser rangefinders and determine the coordinates of the two laser rangefinders according to the coordinates of the midpoints of the two laser rangefinders, the orientation of the UAV, and the distance between the two laser rangefinders.

[0034] As a further solution of the present invention: the distance measurement instruction receiving module includes:

[0035] The initial distance measuring unit is used to calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser;

[0036] The swing distance measuring unit is used for the rangefinder driving mechanism to make the laser rangefinder swing a certain angle, calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser;

[0037] The ranging distance acquisition unit repeats the previous step until the swing stroke of the laser rangefinder is completed, and obtains a number of ranging distances, each ranging distance corresponding to a swing angle.

[0038] As a further solution of the present invention: the cave morphology determination module includes:

[0039] A primary grouping unit is used to group the coordinates of the cave wall points according to the cave wall points obtained by each movement of the drone;

[0040] The closed curve unit is used to fit the coordinates of the cave wall points in each group using a spline curve to obtain several closed curves.

[0041] As a further solution of the present invention: the cave morphology determination module further includes:

[0042] A secondary grouping unit, used for secondary grouping the coordinates of the cave wall points according to the swing angles corresponding to the coordinates of the cave wall points;

[0043] The curve mesh unit is used to use spline curves to fit the coordinates of the cave wall points in each group to obtain a number of long curves. The several long curves and a number of closed curves form a curve mesh, which can reflect the morphology of the cave.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The present invention uses two laser rangefinders to comprehensively scan the drone up, down, left and right, and by inputting the drone movement command, the drone is continuously moved toward the inside of the cave, thereby obtaining a large number of cave wall point coordinates. The cave shape can be determined based on all the cave wall point coordinates. The more and denser the cave wall points are, the more comprehensive and accurate the determined cave shape is. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 This is a schematic diagram of the installation structure of the laser rangefinder.

[0047] Figure 2 This is a schematic diagram of the coordinates of several cave wall points.

[0048] Figure 3 The figure is a flow chart of a cave morphology detection method based on laser ranging.

[0049] Figure 4 The present invention is a flowchart for determining the coordinates of two laser rangefinders in a cave morphology detection method based on laser ranging.

[0050] Figure 5 The present invention is a flow chart for obtaining the swing angle and ranging distance in a cave morphology detection method based on laser ranging.

[0051] Figure 6 The present invention is a flow chart of determining the morphology of a cave according to the coordinates of points on the cave wall in a method of detecting the morphology of a cave based on laser ranging.

[0052] Figure 7 The schematic diagram of the structure of a cave morphology detection system based on laser ranging is shown in FIG.

[0053] Figure 8 The figure is a schematic diagram of the structure of a mobile command receiving module in a cave morphology detection system based on laser ranging.

[0054] Fig. 9 The present invention is a structural schematic diagram of a distance measurement instruction receiving module in a cave morphology detection system based on laser ranging.

[0055] Fig.10 The present invention is a structural schematic diagram of a cave morphology determination module in a cave morphology detection system based on laser ranging. DETAILED DESCRIPTION

[0056] In order to make the purpose, technical solution and advantages of the present invention clearer, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0057] The specific implementation of the present invention is described in detail below in conjunction with specific embodiments.

[0058] like Figure 1 , Figure 2 and Figure 3 As shown, an embodiment of the present invention provides a method for detecting cave morphology based on laser ranging, and the method comprises the following steps:

[0059] S100, receiving a coordinate system establishment command, establishing a coordinate system, taking the midpoint of the two laser rangefinders 001 on the drone as the origin, the two laser rangefinders 001 being symmetrically arranged, taking the vertical upward direction of the origin as the Z axis, taking the nose direction of the drone as the X axis, and determining the Y axis based on the Z axis and the X axis;

[0060] S200, the cave image is obtained through the camera installed on the drone;

[0061] S300, receiving a UAV movement instruction so that the UAV moves a certain distance and then pauses, obtaining a movement route, determining the coordinates of the midpoints of the two laser rangefinders 001 at this time according to the movement route, and determining the coordinates of the two laser rangefinders 001;

[0062] S400, receiving a distance measurement instruction, the laser rangefinder 001 is turned on, and the rangefinder driving mechanism causes the laser rangefinder 001 to swing, obtain a swing angle and a distance measurement, and determine the coordinates 002 of the cave wall point according to the coordinates, swing angle and distance measurement of the laser rangefinder 001;

[0063] S500, repeating the two steps of receiving the drone movement instruction and receiving the distance measurement instruction to obtain a plurality of cave wall point coordinates 002, and determining the cave shape according to the cave wall point coordinates 002.

[0064] It should be noted that the commonly used methods for detecting cave morphology include advance drilling, geophysical drilling, three-high measurement technology, etc. Most of these cave detection technologies are based on the surface and rely on vertical drilling technology to detect caves below the surface. The above technologies have the following defects: the specific internal structure and size of the cave cannot be determined, and complete cave detection cannot be carried out, that is, the specific morphology of the cave cannot be fully known. The embodiments of the present invention aim to solve the above problems.

[0065] In the embodiment of the present invention, the morphology of the cave is detected by an unmanned aerial vehicle. Rangefinder driving mechanisms are installed on both sides of the unmanned aerial vehicle. Laser rangefinders 001 are installed on the rangefinder driving mechanisms. The rangefinder driving mechanisms are used to make the laser rangefinders 001 swing up and down. The two laser rangefinders 001 can realize a comprehensive scan of the unmanned aerial vehicle up, down, left and right. When in use, the unmanned aerial vehicle is first hovered at the entrance of the cave, and then a coordinate system establishment command is input. The embodiment of the present invention automatically establishes a coordinate system, with the midpoint of the two laser rangefinders 001 on the unmanned aerial vehicle as the origin, the vertical upward direction of the origin as the Z axis, and the direction of the nose of the unmanned aerial vehicle as the X axis. The Y axis is determined according to the Z axis and the X axis, and the coordinate system is established. In addition, the camera installed on the unmanned aerial vehicle can obtain the image of the cave, which is convenient for controlling the unmanned aerial vehicle to slowly move toward the inside of the cave, and the unmanned aerial vehicle movement command is input. The unmanned aerial vehicle movement command includes the movement direction and The moving distance is determined so that the UAV pauses after moving a certain distance, and the moving route is obtained. The coordinates of the midpoints of the two laser rangefinders 001 at this time are determined according to the moving route, and then the coordinates of the two laser rangefinders 001 can be obtained. Then, the ranging command is input, the laser rangefinder 001 is automatically turned on, and the rangefinder driving mechanism makes the laser rangefinder 001 swing from top to bottom to obtain the swing angle and the ranging distance. The karst cave wall point coordinates 002 are determined according to the coordinates, swing angle and ranging distance of the laser rangefinder 001. In this way, a group of karst cave wall point coordinates 002 of the UAV at a position can be obtained. Repeat steps S300 and S400 to obtain several groups of karst cave wall point coordinates 002. The karst cave morphology can be determined according to all the karst cave wall point coordinates 002. It is easy to understand that the more the number of karst cave wall point coordinates 002 and the denser the arrangement, the more accurate the determined karst cave morphology.

[0066] like Figure 1 , Figure 2 and Figure 4 As shown, as a preferred embodiment of the present invention, the moving route is obtained, and the coordinates of the midpoints of the two laser rangefinders 001 at this time are determined according to the moving route. The steps of determining the coordinates of the two laser rangefinders 001 specifically include:

[0067] S301, obtaining a moving route through the UAV moving instruction, and determining the coordinates of the midpoints of the two laser rangefinders 001 at this time according to the moving route;

[0068] S302, determining the direction of the UAV by using a magnetic compass installed on the UAV;

[0069] S303, retrieve the distance between the two laser rangefinders 001. The distance between the two laser rangefinders 001 is a fixed value. The coordinates of the two laser rangefinders 001 are determined according to the coordinates of the midpoints of the two laser rangefinders 001, the orientation of the UAV, and the distance between the two laser rangefinders 001.

[0070] In the embodiment of the present invention, in order to determine a set of cave wall point coordinates 002 at each position of the drone, it is first necessary to determine the coordinates of the midpoints of the two laser rangefinders 001 at this position and the orientation of the drone according to the moving route, and then the coordinates of the two laser rangefinders 001 can be determined according to the coordinates of the midpoints of the two laser rangefinders 001, the orientation of the drone and the distance between the two laser rangefinders 001, thereby facilitating the determination of the cave wall point coordinates 002.

[0071] like Figure 1 , Figure 2 and Figure 5 As shown, as a preferred embodiment of the present invention, the rangefinder driving mechanism causes the laser rangefinder 001 to swing, and the steps of obtaining the swing angle and the ranging distance specifically include:

[0072] S401, calculating the current swing angle, emitting laser, and determining the ranging distance after receiving the reflected laser;

[0073] S402, the rangefinder driving mechanism causes the laser rangefinder 001 to swing a certain angle, calculates the current swing angle, emits laser, and determines the distance after receiving the reflected laser;

[0074] S403, repeat the previous step until the swing stroke of the laser rangefinder 001 is completed, and a number of ranging distances are obtained. Each ranging distance corresponds to a swing angle, and the swing angle refers to the angle between the laser emission angle and the Z axis.

[0075] In the embodiment of the present invention, the laser rangefinder 001 is intermittently swung from top to bottom each time, and the swing stroke and the angle of each swing are set in advance. When the laser rangefinder 001 is at the initial position at the top, the current swing angle is determined, and the laser is emitted. After receiving the reflected laser, the ranging distance can be determined. Then, the rangefinder driving mechanism makes the laser rangefinder 001 swing a certain angle, and then the current swing angle is calculated again, and the laser is emitted. After receiving the reflected laser, the ranging distance is determined. The above steps are repeated until the swing stroke of the laser rangefinder 001 is completed, and a plurality of ranging distances are obtained, each ranging distance corresponding to its own swing angle.

[0076] like Figure 1 , Figure 2 and Figure 6 As shown, as a preferred embodiment of the present invention, the step of determining the morphology of the cave according to the coordinates 002 of the cave wall point specifically includes:

[0077] S501, grouping the cave wall point coordinates 002 according to the cave wall points obtained by each movement of the drone;

[0078] S502, using a spline curve to fit the coordinates 002 of the cave wall points in each group to obtain a plurality of closed curves;

[0079] S503, secondary grouping the karst cave wall point coordinates 002 according to the swing angle corresponding to the karst cave wall point coordinates 002;

[0080] S504, using a spline curve to fit the karst cave wall point coordinates 002 in each group to obtain a plurality of long curves, and the plurality of long curves and a plurality of closed curves form a curve mesh.

[0081] In the embodiment of the present invention, in order to make the morphology of the cave more intuitive and accurate, it is necessary to group the cave wall point coordinates 002 according to the cave wall points obtained each time the drone moves, that is, the cave wall point coordinates 002 obtained by the drone at the same position are grouped as a group, and the spline curve is used to fit the cave wall point coordinates 002 in each group to obtain a number of closed curves; then, all the cave wall point coordinates 002 are grouped again according to the swing angle corresponding to the cave wall point coordinates 002, and the spline curve is used to fit the cave wall point coordinates 002 in each group to obtain a number of long strips of curves, and the several long strips of curves and the several closed curves form a curve mesh, which can fully reflect the morphology of the cave.

[0082] like Figure 1 , Figure 2 and Figure 7 As shown, an embodiment of the present invention further provides a cave morphology detection system based on laser ranging, the system comprising:

[0083] The coordinate system establishment module 100 is used to receive a coordinate system establishment command, establish a coordinate system, take the midpoint of the two laser rangefinders 001 on the drone as the origin, the two laser rangefinders 001 are symmetrically arranged, take the vertical upward direction of the origin as the Z axis, take the direction of the drone's nose as the X axis, and determine the Y axis based on the Z axis and the X axis;

[0084] The karst cave image acquisition module 200 is used to obtain the karst cave image through the camera installed on the drone;

[0085] The movement instruction receiving module 300 is used to receive the movement instruction of the UAV, so that the UAV pauses after moving a certain distance, obtains the movement route, determines the coordinates of the midpoints of the two laser rangefinders 001 at this time according to the movement route, and determines the coordinates of the two laser rangefinders 001;

[0086] The distance measurement instruction receiving module 400 is used to receive the distance measurement instruction, the laser distance meter 001 is turned on, and the distance meter driving mechanism causes the laser distance meter 001 to swing, obtain the swing angle and the distance measurement, and determine the coordinates 002 of the cave wall point according to the coordinates, swing angle and distance measurement of the laser distance meter 001;

[0087] The cave morphology determination module 500 is used to repeat the two steps of receiving the drone movement instruction and receiving the distance measurement instruction to obtain a plurality of cave wall point coordinates 002, and determine the cave morphology according to the cave wall point coordinates 002.

[0088] In the embodiment of the present invention, the morphology of the cave is detected by an unmanned aerial vehicle. Rangefinder driving mechanisms are installed on both sides of the unmanned aerial vehicle. Laser rangefinders 001 are installed on the rangefinder driving mechanisms. The rangefinder driving mechanisms are used to make the laser rangefinders 001 swing up and down. The two laser rangefinders 001 can realize a comprehensive scan of the unmanned aerial vehicle up, down, left and right. When in use, the unmanned aerial vehicle is first hovered at the entrance of the cave, and then a coordinate system establishment command is input. The embodiment of the present invention automatically establishes a coordinate system, with the midpoint of the two laser rangefinders 001 on the unmanned aerial vehicle as the origin, the vertical upward direction of the origin as the Z axis, and the direction of the nose of the unmanned aerial vehicle as the X axis. The Y axis is determined according to the Z axis and the X axis, and the coordinate system is established. In addition, the camera installed on the unmanned aerial vehicle can obtain the image of the cave, which is convenient for controlling the unmanned aerial vehicle to slowly move toward the inside of the cave, and the unmanned aerial vehicle movement command is input. The unmanned aerial vehicle movement command includes The moving direction and moving distance are determined so that the UAV pauses after moving a certain distance, and the moving route is obtained. The coordinates of the midpoints of the two laser rangefinders 001 at this time are determined according to the moving route, and then the coordinates of the two laser rangefinders 001 can be obtained. Then the ranging command is input, the laser rangefinder 001 is automatically turned on, and the rangefinder driving mechanism makes the laser rangefinder 001 swing from top to bottom to obtain the swing angle and the ranging distance. The karst cave wall point coordinates 002 are determined according to the coordinates, swing angle and ranging distance of the laser rangefinder 001, so that a group of karst cave wall point coordinates 002 of the UAV at a position can be obtained. Repeat the above steps to obtain several groups of karst cave wall point coordinates 002. The karst cave morphology can be determined according to all the karst cave wall point coordinates 002. It is easy to understand that the more the number of karst cave wall point coordinates 002 and the denser the arrangement, the more accurate the determined karst cave morphology.

[0089] like Figure 1 , Figure 2 and Figure 8 As shown, as a preferred embodiment of the present invention, the movement instruction receiving module 300 includes:

[0090] The midpoint coordinate determination unit 301 is used to obtain a moving route through the UAV moving instruction, and determine the coordinates of the midpoints of the two laser rangefinders 001 at this time according to the moving route;

[0091] The drone orientation unit 302 is used to determine the orientation of the drone using a magnetic compass installed on the drone;

[0092] The rangefinder coordinate unit 303 is used to retrieve the distance between the two laser rangefinders 001 and determine the coordinates of the two laser rangefinders 001 according to the coordinates of the midpoints of the two laser rangefinders 001 , the orientation of the UAV and the distance between the two laser rangefinders 001 .

[0093] like Figure 1 , Figure 2 and Fig. 9 As shown, as a preferred embodiment of the present invention, the distance measurement instruction receiving module 400 includes:

[0094] The initial distance measuring unit 401 is used to calculate the current swing angle, emit laser light, and determine the distance after receiving the reflected laser light;

[0095] The swing distance measuring unit 402 is used for the rangefinder driving mechanism to make the laser rangefinder 001 swing a certain angle, calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser;

[0096] The ranging distance acquisition unit 403 repeats the previous step until the swing stroke of the laser rangefinder 001 is completely completed, and a number of ranging distances are obtained, each ranging distance corresponding to a swing angle.

[0097] like Figure 1 , Figure 2 and Fig.10 As shown, as a preferred embodiment of the present invention, the cave morphology determination module 500 includes:

[0098] A primary grouping unit 501 is used to group the karst cave wall point coordinates 002 according to the karst cave wall points obtained by each movement of the drone;

[0099] A closed curve unit 502 is used to fit the cave wall point coordinates 002 in each group using a spline curve to obtain a plurality of closed curves;

[0100] A secondary grouping unit 503, used for secondary grouping the karst cave wall point coordinates 002 according to the swing angle corresponding to the karst cave wall point coordinates 002;

[0101] The curve mesh unit 504 is used to use spline curves to fit the karst cave wall point coordinates 002 in each group to obtain a number of long curves. The several long curves and the several closed curves form a curve mesh, which can reflect the morphology of the karst cave.

[0102] The above only describes in detail the preferred embodiments of the present invention, which is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

[0103] It should be understood that, although each step in the flow chart of each embodiment of the present invention is shown in sequence according to the indication of the arrow, these steps are not necessarily performed in sequence according to the order indicated by the arrow. Unless there is a clear explanation in this article, the execution of these steps does not have a strict order restriction, and these steps can be performed in other orders. Moreover, at least a portion of the steps in each embodiment may include a plurality of sub-steps or a plurality of stages, and these sub-steps or stages are not necessarily performed at the same time, but can be performed at different times, and the execution order of these sub-steps or stages is not necessarily performed in sequence, but can be performed in turn or alternately with at least a portion of other steps or sub-steps or stages of other steps.

[0104] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, storage, database or other media used in the embodiments provided in this application may include non-volatile and / or volatile memory. Non-volatile memory may include read-only memory (ROM), programmable ROM (PROM), electrically programmable ROM (EPROM), electrically erasable programmable ROM (EEPROM) or flash memory. Volatile memory may include random access memory (RAM) or external cache memory. As an illustration and not limitation, RAM is available in many forms, such as static RAM (SRAM), dynamic RAM (DRAM), synchronous DRAM (SDRAM), double data rate SDRAM (DDRSDRAM), enhanced SDRAM (ESDRAM), synchronous link (Synchlink) DRAM (SLDRAM), memory bus (Rambus) direct RAM (RDRAM), direct memory bus dynamic RAM (DRDRAM), and memory bus dynamic RAM (RDRAM).

[0105] Those skilled in the art will readily appreciate other embodiments of the present disclosure after considering the disclosure in the specification and examples. This application is intended to cover any variations, uses or adaptations of the present disclosure, which follow the general principles of the present disclosure and include common knowledge or customary techniques in the art that are not disclosed in the present disclosure. The specification and examples are intended to be exemplary only, and the true scope and spirit of the present disclosure are indicated by the claims.

Claims

1. A method for detecting cave morphology based on laser ranging, characterized in that: The method comprises the following steps: Receive the coordinate system establishment command, establish the coordinate system, take the midpoint of the two laser rangefinders on the drone as the origin, set the two laser rangefinders symmetrically on the left and right, take the vertical upward direction of the origin as the Z axis, take the direction of the drone's nose as the X axis, and determine the Y axis based on the Z axis and the X axis; The cave images were obtained through the camera installed on the drone; Receive the UAV movement instruction, so that the UAV moves a certain distance and then pauses, obtain the movement route, determine the coordinates of the midpoints of the two laser rangefinders at this time according to the movement route, and determine the coordinates of the two laser rangefinders; Receiving the distance measurement instruction, the laser rangefinder is turned on, and the rangefinder driving mechanism causes the laser rangefinder to swing, obtain the swing angle and the distance measurement, and determine the coordinates of the cave wall point according to the coordinates of the laser rangefinder, the swing angle and the distance measurement; Repeat the two steps of receiving the UAV movement instruction and receiving the distance measurement instruction to obtain the coordinates of several cave wall points, and determine the cave shape according to the coordinates of the cave wall points; The steps of obtaining the moving route, determining the coordinates of the midpoints of the two laser rangefinders at this time according to the moving route, and determining the coordinates of the two laser rangefinders specifically include: The moving route is obtained through the UAV moving instructions, and the coordinates of the midpoints of the two laser rangefinders at this time are determined according to the moving route; Determine the direction of the drone using the magnetic compass installed on the drone; The distance between the two laser rangefinders is retrieved, and the coordinates of the two laser rangefinders are determined according to the coordinates of the midpoints of the two laser rangefinders, the orientation of the UAV, and the distance between the two laser rangefinders; The rangefinder driving mechanism causes the laser rangefinder to swing, and the steps of obtaining the swing angle and the ranging distance specifically include: Calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser; The rangefinder driving mechanism makes the laser rangefinder swing a certain angle, calculates the current swing angle, emits laser, and determines the distance after receiving the reflected laser; Repeat the previous step until the swing stroke of the laser rangefinder is completed, and obtain several ranging distances, each ranging distance corresponds to a swing angle; The step of determining the morphology of the cave according to the coordinates of the cave wall points specifically includes: The coordinates of the cave wall points are grouped according to the cave wall points obtained from each drone movement; Use spline curves to fit the coordinates of the cave wall points in each group to obtain several closed curves; The step of fitting the coordinates of the cave wall points in each group by using a spline curve to obtain a plurality of closed curves also includes: The coordinates of the cave wall points are secondary grouped according to the swing angles corresponding to the coordinates of the cave wall points; The spline curve is used to fit the coordinates of the cave wall points in each group to obtain a number of long curves. The long curves and a number of closed curves form a curve mesh surface, which can reflect the morphology of the cave.

2. A cave morphology detection system based on laser ranging, characterized in that: The system comprises: The coordinate system establishment module is used to receive the coordinate system establishment command and establish the coordinate system. The midpoint of the two laser rangefinders on the drone is taken as the origin. The two laser rangefinders are set symmetrically on the left and right. The vertical upward direction of the origin is taken as the Z axis, and the direction of the drone's nose is taken as the X axis. The Y axis is determined according to the Z axis and the X axis. The cave image acquisition module is used to obtain the cave image through the camera installed on the UAV; The moving instruction receiving module is used to receive the moving instruction of the UAV, so that the UAV pauses after moving a certain distance, obtains the moving route, determines the coordinates of the midpoints of the two laser rangefinders at this time according to the moving route, and determines the coordinates of the two laser rangefinders; The distance measurement instruction receiving module is used to receive the distance measurement instruction, the laser distance meter is turned on, and the distance meter driving mechanism causes the laser distance meter to swing, obtain the swing angle and the distance measurement, and determine the coordinates of the cave wall point according to the coordinates of the laser distance meter, the swing angle and the distance measurement; The cave morphology determination module is used to repeat the two steps of receiving the UAV movement instruction and receiving the distance measurement instruction to obtain the coordinates of several cave wall points, and determine the cave morphology according to the coordinates of the cave wall points; The mobile instruction receiving module comprises: A midpoint coordinate determination unit is used to obtain a moving route through a UAV moving instruction, and determine the coordinates of the midpoints of the two laser rangefinders at this time according to the moving route; A drone heading unit, used to determine the heading of the drone through a magnetic compass installed on the drone; The rangefinder coordinate unit is used to retrieve the distance between the two laser rangefinders and determine the coordinates of the two laser rangefinders according to the coordinates of the midpoints of the two laser rangefinders, the orientation of the UAV, and the distance between the two laser rangefinders; The ranging instruction receiving module comprises: The initial distance measuring unit is used to calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser; The swing distance measuring unit is used for the rangefinder driving mechanism to make the laser rangefinder swing a certain angle, calculate the current swing angle, emit laser, and determine the distance after receiving the reflected laser; The ranging distance acquisition unit repeats the previous step until the swing stroke of the laser rangefinder is completely completed, and a number of ranging distances are obtained, each ranging distance corresponding to a swing angle; The cave morphology determination module comprises: A primary grouping unit is used to group the coordinates of the cave wall points according to the cave wall points obtained by each movement of the drone; A closed curve unit is used to fit the coordinates of the cave wall points in each group using a spline curve to obtain a number of closed curves; The cave morphology determination module also includes: A secondary grouping unit, used for secondary grouping the coordinates of the cave wall points according to the swing angles corresponding to the coordinates of the cave wall points; The curve mesh unit is used to use spline curves to fit the coordinates of the cave wall points in each group to obtain a number of long curves. The several long curves and a number of closed curves form a curve mesh, which can reflect the morphology of the cave.

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