Disclosure of Invention
In order to solve the defects in the prior art, the invention aims to provide a cable tunnel unmanned aerial vehicle inspection self-adaptive control method, a system, a terminal and a medium, which can correct the flight direction of the unmanned aerial vehicle at regular time and realize the self-adaptive control of the unmanned aerial vehicle flying along the extending direction of the cable tunnel under the condition of poor illumination condition and weak signal coverage.
The technical aim of the invention is realized by the following technical scheme:
In a first aspect, a method for adaptively controlling inspection of a cable tunnel unmanned aerial vehicle is provided, wherein the unmanned aerial vehicle is configured with a camera and a plurality of ranging sensors symmetrically distributed around the camera, and the method comprises the following steps:
acquiring oblique measurement distances between the unmanned aerial vehicle and the inner wall of the cable tunnel in the flight process by a distance measuring sensor, wherein a plurality of oblique measurement distances acquired at the same moment form a distance sequence;
Determining a flight reference plane of the unmanned aerial vehicle by taking the measurement direction of a ranging sensor corresponding to the largest and the smallest inclinometry distances in the distance sequence and the central view angle direction of the camera as constraint;
solving a flying pitch angle of the unmanned aerial vehicle in a flying reference plane according to the inner diameter of the cable tunnel, the maximum inclinometry distance, the minimum inclinometry distance and the inclinometry angle of the ranging sensor;
and correcting the flight direction of the unmanned aerial vehicle according to the flight reference plane and the flight pitch angle, and simultaneously starting a camera to acquire images.
Further, the oblique measurement angle between the ranging direction of each ranging sensor and the central viewing angle direction of the camera is equal.
Further, the flight pitch angle solving expression of the unmanned aerial vehicle in the flight reference plane is specifically as follows:
；
Wherein,Representing the inside diameter of the cable tunnel; representing the maximum or minimum inclinometry distance acquired by a ranging sensor located on the look-up side in the flight reference plane; representing the minimum oblique measurement distance or the maximum oblique measurement distance acquired by the ranging sensor positioned on the overlook side in the flight reference plane, wherein the look-up side and the overlook side in the flight reference plane are divided by taking the central viewing angle direction of the camera as a boundary line; representing the inclinometry angle of the ranging sensor; representing the flying pitch angle of the unmanned aerial vehicle in a flying reference plane, wherein the value is more than 0 and is the depression angle, and the value is less than 0 and is the elevation angle;
And whenAt minimum oblique distance, thenIs the maximum inclinometry distance; conversely, whenAt the maximum oblique measurement distance, thenIs the minimum bevel distance.
Further, the method further comprises:
solving the offset distance of the unmanned aerial vehicle, which deviates from the center of the cable tunnel, in the flight reference plane according to the maximum inclinometry distance and the flight pitch angle of the unmanned aerial vehicle in the flight reference plane;
Or solving the offset distance of the unmanned aerial vehicle deviating from the center of the cable tunnel in the flight reference plane according to the minimum inclinometry distance and the flight pitch angle of the unmanned aerial vehicle in the flight reference plane.
Further, the calculation formula of the offset distance specifically includes:
；
Or, the calculation formula of the offset distance is specifically:
；
Wherein,Expressed in terms ofThe offset distance solved for the basis; Expressed in terms ofThe offset distance is solved for as a basis.
Further, the method further comprises:
After correcting the flight direction of the unmanned aerial vehicle according to the flight reference plane and the flight pitch angle, calculating to obtain a pitch angle variable in unit time according to the ratio of the flight pitch angle to a correction period;
and in the next correction period, dynamically correcting the flight direction of the unmanned aerial vehicle according to the pitch angle variable in the unit time.
Further, the method further comprises:
in the flight process of the unmanned aerial vehicle, a plurality of ranging sensors are synchronously controlled to circularly rotate in a positive and negative alternate mode in the circumferential direction of self distribution, and each ranging sensor correspondingly acquires an oblique ranging distance set;
when the maximum oblique measurement distance and the minimum oblique measurement distance are extracted from the distance sequence, deleting the abnormal data in the oblique measurement distance set;
All the inclinations in the inclinations are monotonous change trend in time sequence, and the abnormal data are data of extreme points of the inclinations.
In a second aspect, a cable tunnel unmanned aerial vehicle inspection adaptive control system is provided, and the system is used for implementing the cable tunnel unmanned aerial vehicle inspection adaptive control method according to the first aspect, and includes:
The distance acquisition module is used for acquiring the oblique measurement distance between the unmanned aerial vehicle and the inner wall of the cable tunnel in the flight process through the distance measurement sensor, and a plurality of oblique measurement distances acquired at the same moment form a distance sequence;
The plane determining module is used for determining a flight reference plane of the unmanned aerial vehicle by taking the same plane as a constraint of the measuring direction of the ranging sensor corresponding to the largest and the smallest inclinometric distances in the distance sequence and the central visual angle direction of the camera;
The angle solving module is used for solving the flying pitch angle of the unmanned aerial vehicle in the flying reference plane according to the inner diameter of the cable tunnel, the maximum inclinometry distance, the minimum inclinometry distance and the inclinometry angle of the ranging sensor;
and the correction control module is used for correcting the flight direction of the unmanned aerial vehicle according to the flight reference plane and the flight pitch angle, and simultaneously starting the camera to acquire images.
In a third aspect, a computer terminal is provided, including a memory, a processor, and a computer program stored in the memory and executable on the processor, where the processor implements the method for adaptively controlling inspection of a cable tunnel unmanned aerial vehicle according to any one of the first aspects when the processor executes the program.
In a fourth aspect, a computer readable medium is provided, on which a computer program is stored, the computer program being executable by a processor to implement the method for adaptively controlling inspection of a cable tunnel drone according to any one of the first aspects.
Compared with the prior art, the invention has the following beneficial effects:
1. According to the cable tunnel unmanned aerial vehicle routing inspection self-adaptive control method, the distance measurement sensors symmetrically distributed around the camera are used for measuring the inclined measurement distance between the unmanned aerial vehicle and the inner wall of the cable tunnel in the flight process, the flight reference plane representing the bending direction of the cable tunnel is determined according to the measurement direction of the distance measurement sensor corresponding to the largest inclined measurement distance and the smallest inclined measurement distance, and then the flight pitch angle of the unmanned aerial vehicle in the flight reference plane is solved by combining the inner diameter of the cable tunnel, the largest inclined measurement distance, the smallest inclined measurement distance and the inclined measurement angle of the distance measurement sensor, so that the flight direction of the unmanned aerial vehicle can be corrected at regular time, and the self-adaptive control of the unmanned aerial vehicle in the extending direction of the cable tunnel can be realized under the conditions of poor illumination and weak signal coverage;
2. According to the method, the offset distance of the unmanned aerial vehicle deviating from the center of the cable tunnel in the flight reference plane is solved according to the flight pitch angle of the unmanned aerial vehicle in the flight reference plane and the maximum inclinometry distance or the minimum inclinometry distance, and the unmanned aerial vehicle can be controlled to fly along the central axis direction in the cable tunnel as much as possible according to the offset distance, so that the flight safety and stability of the unmanned aerial vehicle are effectively ensured;
3. according to the method, after the flight direction of the unmanned aerial vehicle is corrected according to the flight reference plane and the flight pitch angle, in the next correction period, the flight direction of the unmanned aerial vehicle is dynamically corrected according to the pitch angle variable in the unit time, so that the probability of collision of the unmanned aerial vehicle at a position with a large cable tunnel bending degree can be reduced, and the flight safety of the unmanned aerial vehicle is improved;
4. According to the invention, in the flight process of the unmanned aerial vehicle, the plurality of ranging sensors are synchronously controlled to circularly rotate in a positive and negative alternate mode in the circumferential direction of the distribution of the unmanned aerial vehicle, each ranging sensor correspondingly acquires an oblique measurement distance set, when the maximum oblique measurement distance and the minimum oblique measurement distance are extracted from the distance sequence, abnormal data in the oblique measurement distance set are deleted, interference of a pipeline or a cable in a cable tunnel in the distance measurement process can be filtered, and the accuracy and reliability of the oblique measurement distance are effectively improved.
Detailed Description
For the purpose of making apparent the objects, technical solutions and advantages of the present invention, the present invention will be further described in detail with reference to the following examples and the accompanying drawings, wherein the exemplary embodiments of the present invention and the descriptions thereof are for illustrating the present invention only and are not to be construed as limiting the present invention.
Example 1: the invention relates to a cable tunnel unmanned aerial vehicle routing inspection self-adaptive control method, wherein the unmanned aerial vehicle is provided with a camera and a plurality of ranging sensors symmetrically distributed around the camera, as shown in fig. 1, and comprises the following steps:
S1: acquiring oblique measurement distances between the unmanned aerial vehicle and the inner wall of the cable tunnel in the flight process by a distance measuring sensor, wherein a plurality of oblique measurement distances acquired at the same moment form a distance sequence;
s2: determining a flight reference plane of the unmanned aerial vehicle by taking the measurement direction of a ranging sensor corresponding to the largest and the smallest inclinometry distances in the distance sequence and the central view angle direction of the camera as constraint;
s3: solving a flying pitch angle of the unmanned aerial vehicle in a flying reference plane according to the inner diameter of the cable tunnel, the maximum inclinometry distance, the minimum inclinometry distance and the inclinometry angle of the ranging sensor;
S4: and correcting the flight direction of the unmanned aerial vehicle according to the flight reference plane and the flight pitch angle, and simultaneously starting a camera to acquire images.
In step S1, the oblique measurement angle between the ranging direction of each ranging sensor and the center viewing angle direction of the camera is equal. The ranging directions of the plurality of ranging sensors are in conical and divergent distribution, and in general, the number of the ranging sensors is even, every two ranging sensors form a group, and the difference of the arrangement azimuth angles of the two ranging sensors in the group is 180 degrees.
In step S2, the maximum oblique measurement distance and the minimum oblique measurement distance can better indicate the bending direction of the cable tunnel, but considering that two maximum oblique measurement distances and two minimum oblique measurement distances may exist in one distance sequence at the same time, when determining the flight reference plane of the unmanned aerial vehicle, the center view angle direction of the camera can also be in the same plane as the supplementary constraint, so as to realize accurate determination of the flight reference plane.
In addition, the distance measuring sensor corresponding to the extracted maximum and minimum oblique measuring distances is a group of distance measuring sensors as a screening condition to screen out the final maximum and minimum oblique measuring distances.
As shown in fig. 2 and 3, the measurement directions of the four ranging sensors are A, B, C, D, respectively, O is a camera, and Z is a center viewing angle direction of the camera. In this embodiment, the minimum oblique measurement distance is acquired by the ranging sensor corresponding to the measurement direction B, and the maximum oblique measurement distance is acquired by the ranging sensor corresponding to the measurement direction D, so the flight reference plane is the BDZ plane.
In step S3, considering that the difference of the lengths of the curved tunnel and the straight tunnel is smaller in a shorter distance, for this purpose, in the invention, when solving the flying pitch angle, the axial section of the cable tunnel is equivalent to a rectangular plane, as shown in fig. 3, the flying pitch angle solving expression of the unmanned plane in the flying reference plane is specifically:
；
Wherein,Representing the inside diameter of the cable tunnel; representing the maximum or minimum inclinometry distance acquired by a ranging sensor located on the look-up side in the flight reference plane; representing the minimum oblique measurement distance or the maximum oblique measurement distance acquired by the ranging sensor positioned on the overlook side in the flight reference plane, wherein the look-up side and the overlook side in the flight reference plane are divided by taking the central viewing angle direction of the camera as a boundary line; representing the inclinometry angle of the ranging sensor; The flying pitch angle of the unmanned aerial vehicle in the flying reference plane is represented, wherein the value is larger than 0 and is the depression angle, and the value is smaller than 0 and is the elevation angle.
The flying pitch angle represents the angle difference between the central view angle direction (shooting direction) of the camera and the extending direction of the cable tunnel, and if the flying pitch angle is the depression angle, the depression angle of the unmanned aerial vehicle needs to be controlled to be reduced, namely the front end of the unmanned aerial vehicle is lifted for flying; if the flying pitch angle is the elevation angle, the elevation angle of the unmanned aerial vehicle needs to be controlled to be reduced, namely the front end of the unmanned aerial vehicle flies with low pressure.
It should be noted that the elevation angle, the depression angle, the elevation angle, and the depression are all relative conditions described based on the fact that the flight reference plane is regarded as the vertical plane.
The cable tunnel unmanned aerial vehicle inspection self-adaptive control method can control the unmanned aerial vehicle to fly along the central axis direction in the cable tunnel as much as possible, effectively ensures the safety and stability of the unmanned aerial vehicle, and solves the offset distance of the unmanned aerial vehicle deviating from the center of the cable tunnel in the flight reference plane according to the minimum oblique measurement distance and the flight pitch angle of the unmanned aerial vehicle in the flight reference plane.
As shown in the figure 3 of the drawings,Representing the distance between the unmanned aerial vehicle in the flight reference plane and the cable tunnel near the measuring direction B sideThe distance between the drone in the flight reference plane and the cable tunnel near the measurement direction D side is shown. The invention solves the problems firstlyAndIs further calculated byAndSubtracting the corresponding average value of (2)Or (b)The offset distance can be calculated.
For example, the calculation formula of the offset distance is specifically:
；
Wherein,Expressed in terms ofThe offset distance is solved for as a basis. When the following is performedThe smallest inclinometry distance is acquired, thenThe maximum inclinometry distance is collected; conversely, whenWhen the maximum inclinometry distance is acquired, thenThe smallest inclinometric distance is collected.
As shown in the figure 3 of the drawings,The smallest inclinometry distance is acquired, if at this timeThe value of (2) is greater than 0, which can be based onControlling unmanned aerial vehicle edge deviation measurementIs moved in the direction of the distance measuring sensor.
In addition, the offset distance of the unmanned aerial vehicle, which deviates from the center of the cable tunnel in the flight reference plane, can be solved according to the maximum inclinometry distance and the flight pitch angle of the unmanned aerial vehicle in the flight reference plane.
For example, the calculation formula of the offset distance is specifically:
；
Wherein,Expressed in terms ofThe offset distance is solved for as a basis. When the following is performedThe smallest inclinometry distance is acquired, thenThe set is the maximum inclinometry distance; conversely, whenWhen the maximum inclinometry distance is acquired, thenThe smallest inclinometric distance is collected.
As shown in the figure 3 of the drawings,The maximum inclinometry distance is collected. If at this timeThe value of (2) is greater than 0, which can be based onControlling unmanned aerial vehicle edge deviation measurementIs moved in the direction of the distance measuring sensor.
According to the cable tunnel unmanned aerial vehicle routing inspection self-adaptive control method, in order to reduce the probability of collision of the unmanned aerial vehicle at a position with a large cable tunnel bending degree, the flight safety of the unmanned aerial vehicle is improved, after the flight direction of the unmanned aerial vehicle is corrected according to a flight reference plane and a flight pitch angle, the pitch angle variable in unit time is calculated according to the ratio of the flight pitch angle to a correction period; and in the next correction period, dynamically correcting the flight direction of the unmanned aerial vehicle according to the pitch angle variable in the unit time.
In addition, in the flight process of the unmanned aerial vehicle, a plurality of ranging sensors are synchronously controlled to circularly rotate in a positive and negative alternating mode in the circumferential direction of self distribution, and each ranging sensor is correspondingly acquired to obtain an oblique ranging distance set; when the maximum oblique measurement distance and the minimum oblique measurement distance are extracted from the distance sequence, deleting the abnormal data in the oblique measurement distance set; all the inclinations in the inclinations are monotonous change trend in time sequence, and the abnormal data are data of extreme points of the inclinations.
The invention can filter the interference of the pipeline or the cable in the cable tunnel to the distance measurement process, and effectively improves the accuracy and reliability of the oblique distance measurement.
Example 2: the system is used for realizing the cable tunnel unmanned aerial vehicle inspection self-adaptive control method as described in the embodiment 1, and comprises a distance acquisition module, a plane determination module, an angle solving module and a correction control module as shown in fig. 4.
The distance acquisition module is used for acquiring the oblique measurement distance between the unmanned aerial vehicle and the inner wall of the cable tunnel in the flight process through the distance measurement sensor, and a plurality of oblique measurement distances acquired at the same moment form a distance sequence; the plane determining module is used for determining a flight reference plane of the unmanned aerial vehicle by taking the same plane as a constraint of the measuring direction of the ranging sensor corresponding to the largest and the smallest inclinometric distances in the distance sequence and the central visual angle direction of the camera; the angle solving module is used for solving the flying pitch angle of the unmanned aerial vehicle in the flying reference plane according to the inner diameter of the cable tunnel, the maximum inclinometry distance, the minimum inclinometry distance and the inclinometry angle of the ranging sensor; and the correction control module is used for correcting the flight direction of the unmanned aerial vehicle according to the flight reference plane and the flight pitch angle, and simultaneously starting the camera to acquire images.
The invention also discloses a computer terminal which comprises a memory, a processor and a computer program stored in the memory and capable of running on the processor, wherein the processor realizes the cable tunnel unmanned aerial vehicle inspection self-adaptive control method as described in the embodiment 1 when executing the program.
The present invention also describes a computer-readable medium having stored thereon a computer program that is executed by a processor to implement the cable tunnel unmanned aerial vehicle inspection adaptive control method described in embodiment 1.
Working principle: according to the invention, the distance measurement sensors symmetrically distributed around the camera are used for measuring the oblique measurement distance between the unmanned aerial vehicle and the inner wall of the cable tunnel in the flight process, the flight reference plane representing the bending direction of the cable tunnel is determined according to the measurement directions of the distance measurement sensors corresponding to the maximum oblique measurement distance and the minimum oblique measurement distance, and then the flight pitch angle of the unmanned aerial vehicle in the flight reference plane is solved by combining the inner diameter of the cable tunnel, the maximum oblique measurement distance, the minimum oblique measurement distance and the oblique measurement angle of the distance measurement sensors, so that the flight direction of the unmanned aerial vehicle can be corrected at regular time, and the self-adaptive control of the unmanned aerial vehicle in the flight direction of the cable tunnel can be realized under the conditions of poor illumination and weak signal coverage.
It will be appreciated by those skilled in the art that embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.
The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems) and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flowchart illustrations and/or block diagrams, and combinations of flows and/or blocks in the flowchart illustrations and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.
These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.
The foregoing description of the embodiments has been provided for the purpose of illustrating the general principles of the invention, and is not meant to limit the scope of the invention, but to limit the invention to the particular embodiments, and any modifications, equivalents, improvements, etc. that fall within the spirit and principles of the invention are intended to be included within the scope of the invention.