KR102416330B1 - system for remote coordinate measurement using drone sytem - Google Patents

Abstract

The present invention relates to a remote coordinate measurement system using a drone system, and a drone system in which a distance measurement for the 3D coordinate image is also performed in parallel in the process of capturing and collecting a 3D coordinate image of a target site remotely through a flying drone; A drone controller for flight control of a drone, a portable terminal that receives a 3D coordinate image measured from the drone system from a satellite, and remotely operates a 3D coordinate image of the drone, and 3D coordinates transmitted from the portable terminal An object of the present invention is to provide a remote coordinate measurement system using a drone system including a management server that stores coordinate measurement data for an image as a DB or transmits the DB to the portable terminal in some cases.

Description

A remote coordinate measurement system using a drone system {system for remote coordinate measurement using drone system}

The present invention relates to a remote coordinate measurement system using a drone system, and calculates remote coordinate values using a target tracking camera and a range finder and an angle measurement sensor mounted on a drone, and based on these remote coordinate values It is about a remote coordinate measurement system using a drone system that can be used for real-time work in the cadastral field by visualizing the calculated horizontal distance information through the monitor screen of the platform-based server.

In general, calculation of horizontal distance through coordinate measurement in the cadastral field is performed through prism measurement between an instrument carrier and a pole man using a total station on the ground. A total station is a device that observes a distance, a vertical angle, and a horizontal angle with a single machine. In other terms, it is also called an electronic tacheometer, for example, an optical wave rangefinder.

Light Wave Rangefinder (Light Wave Rangefinder, 光波距離測定器) is a geodetic device that installs a reflector at the point to be measured and measures the distance using the reflected wave of the transmitted beam. It may consist of a light-wave rangefinder.

In coordinate measurement using such an optical wave rangefinder, coordinate measurement and The distance measurement for this is performed in a manual work method.

In particular, in the forest area, collimation is difficult due to topographical characteristics and obstacles such as trees, and the line of sight between the distance measurement target point and the range finder must be secured even in a level place where measurement is relatively easy. do.

As such, in the coordinate measurement in the cadastral field, when using the observation equipment of the existing total station, the calculation itself is sometimes impossible due to the rugged topographical characteristics, and even if the calculation is not performed However, the time and cost required for this will inevitably increase, and the accuracy of the results obtained by calculation will inevitably decrease.

For these reasons, innovative improvement in the method of calculating the horizontal distance through coordinate measurement is urgently required. On the other hand, it can be referred to as a patent document disclosed in the following prior art document is a patent document relating to a target point coordinate extraction system and method.

Patent Document 001: Republic of Korea Patent Registration No. 10-1954748 (Registration Date February 27, 2019)

The present invention for solving the above problems is to provide a remote coordinate measurement system using a drone system that conveniently performs the work process of coordinate measurement for a target site of the terrain and guarantees the accuracy of the coordinate measurement result. has that purpose.

The present invention for achieving the above objects is a drone system in which the distance measurement for the 3D coordinate image is also paralleled in the process of capturing and collecting 3D coordinate images of a target site remotely through a flying drone, and flight control of the drone A drone controller for, and a portable terminal that receives a 3D coordinate image measured from the drone system from a satellite, and remotely operates a 3D coordinate image of the drone, and coordinates for a 3D coordinate image transmitted from the portable terminal There is one feature in a remote coordinate measurement system using a drone system including a management server that stores measurement data as a DB or transmits the DB to the portable terminal in some cases.

A camera mounted on the drone to take a 3D coordinate image of the target site in the process of stationary flight of the drone, and a camera mounted on the drone to calculate the distance value data in a way that calculates the time difference between sound waves and the distance to the target site, the 3D There is one feature in a remote coordinate measurement system using a drone system that further includes a distance measurer for securing distance value data for a coordinate image.

There is one feature in a remote coordinate measurement system using a drone system in which an encoder sensor is used as an angle measuring sensor that accurately detects a rotation angle in the rotation operation process of the camera.

The distance meter is a sound wave detector that calculates distance value data in a way that calculates the time difference between sound waves transmitted from a fixed sound wave detection system built in the target area, and the corresponding distance value data of individual sound waves transmitted from the sound wave detection system of the beacon There is one feature in a remote coordinate measurement system using a drone system that further includes a beacon receiver that distinguishes individual signals in a manner of receiving them.

For universal utility as remote coordinate data for the 3D coordinate image obtained from the camera, control of the left and right rotation and vertical rotation of the camera is performed remotely through a remote image control application installed in the portable terminal. There is one feature in the used remote coordinate measurement system.

According to the present invention as described above, since coordinate measurement of a target area of a terrain can be performed remotely using a drone, it can be expected that the workability of coordinate measurement is remarkably improved. It is possible to shorten the cost and time period for coordinate measurement due to the reduction of manpower and time, and above all, the accuracy and universal utility of the coordinate measurement result can be guaranteed, so that its reliability can be improved compared to competitors.

1 is a diagram schematically illustrating the overall configuration of a remote coordinate measurement system using a drone system according to an embodiment of the present invention.
2 is a diagram showing an arbitrary specific target, that is, an arbitrary point, as an example on an image captured by a camera configured in a drone system.
3 is a diagram schematically illustrating a process of controlling a camera to bring a specific target, that is, an arbitrary point, shown in FIG. 2 to the center of the image with a remote image control application installed in a portable terminal.
4 is a flowchart illustrating a flow of a distance calculation process through sound waves.

It is revealed that the drawings attached to this specification are exaggerated for clarity and convenience of explanation, and the embodiments described in the present specification are only the most preferred embodiments of the present invention, and do not represent all of the technical spirit of the present invention. Therefore, it should be understood that there may be various equivalents and modifications that can be substituted for them at the time of the present application. In addition, the scope of the present invention is not limited to the embodiments, but should be interpreted based on the technical idea throughout the specification in consideration of the implementation of various other modifications.

With reference to the accompanying drawings, a remote coordinate measurement system using a drone system according to an embodiment of the present invention is a drone system 10, a drone controller 20, a portable terminal 30, and a management server as shown in FIG. 40, the drone system 10 includes a drone 100 flying toward a target area for remote coordinate measurement, a GPS receiver 110 grafted to the drone, and an inertial navigation device ( 120), the camera 130, the range finder 140, and may be configured to further include an angle measuring sensor (150).

Of course, the management server 40 may be used for storing the remote coordinate measurement data transmitted from the portable terminal 30 as a DB or transmitting the DB to the portable terminal 30, and the drone 100 is a drone system 10 equipped with a GPS receiver 110 , an inertial navigation device 120 , a camera 130 , a range finder 140 , and an angle measurement sensor 150 .

The drone 100 may be automatically flown through the inertial navigation device 120, and in some cases, may also be operated by an artificial control method through a manipulator, and the camera 130 installed in the drone 100. may capture and collect a 3D coordinate image as shown in FIG. 2 for the remote coordinate measurement data, and the distance measurer 140 may secure distance value data for the 3D coordinate image.

In particular, the camera 130 can accurately operate the rotation angle for taking a 3D coordinate image of the target based on the detection signal detected from the angle measuring sensor 150, and the angle measuring sensor 150 is It is desirable to apply an encoder sensor suitable for accurate rotational angle operation detection of the camera 130 .

Of course, the distance measuring device 140 may be configured in a way that a sonar sensor and a beacon receiver are combined, and a fixed sound wave detection system may be built in the target site. As a measure for this, it can be composed of individual wedge rods that are easy to be embedded in or pulled out of the target site, and a beacon and a sound wave oscillator that are fixedly installed on top of individual wedge rods.

Therefore, in the process of the drone 100 flying still at low altitude at the target site, the sound wave sensor of the distance measuring device 140 grafted to the drone 100 is a sound wave detection system fixedly installed on the target site. distance value data can be extracted in this way, and the beacon receiver of the range finder 140 receives individual signals of beacons as the sound wave detection system. It is possible to distinguish the corresponding distance value data that can be calculated as .

In Table 1 below, it can be seen that sound waves and ultrasonic waves have much superiority in terms of price, convenience, and precision compared to satellites or lasers.

characteristic
type price convenience precision sonic and ultrasound I go go satellite go I go laser go I go

The frequency used in the sound wave can be changed according to the situation by passing the frequency generated by the sound wave oscillator through a divider. The distance can be calculated by going through the calculation module, and the distance calculation module has a built-in microcomputer for calculating the time difference of sound waves.

In particular, since the filter can remove the congestion noise mixed with the sound wave, the uniqueness of the sound wave can be improved, the envelope detector can distinguish the sound wave waveforms, and the comparator can distinguish the sound wave waveform from the envelope detector. It is possible to compare and measure whether they are properly distinguished.

Looking at the flow of the distance calculation process through these sound waves, as shown in Fig. 4, when the frequency signal of the sound wave emitted from the sound wave oscillator is generated (S1), the process of amplifying the sound wave in the amplifier through the condenser microphone ( S2) is passed.

After that, the process (S3) of removing the congestion sound included in the sound wave through a filter is performed, and then, the waveforms of the sound wave transmitted from the individual sound wave oscillators can be distinguished (S4) through the envelope detector, and then the separated sound wave The values may be measured (S5) in a way that they are compared through a comparator.

As such, distance value data can be calculated by calculating the time difference of sound waves by the microcomputer of the distance calculation module for sound waves that have been compared and measured, so that distance value data for the 3D coordinate image can be secured.

Of course, in this case, if an error occurs in the comparison measurement of sound waves due to a failure of the comparator in the process S5, the process returns to the process S4 corresponding to the entire process according to the indication signal of the microcomputer.

If an error does not occur in distinguishing the waveform of the sound wave in the process S4, the microcomputer of the distance calculation module determines that there is no error with respect to the sound wave and calculates the time difference of the sound wave. have.

However, when an error occurs in distinguishing the waveforms of sound waves due to the failure of the envelope detector in the process S4, the process returns to the process S3 corresponding to the entire process according to the instruction signal of the microcomputer.

If an error does not occur in removing the congestion sound included in the sound wave in the process S3, the microcomputer of the distance calculation module determines that there is no error in the sound wave and calculates the time difference of the sound wave. can be recalculated.

As such, since the feedback is implemented three times from the transmitted sound wave to the distance calculation of the microcomputer, the error variable of the sound wave can be quickly identified and processed, thereby ensuring the accuracy of the distance value data.

On the other hand, the camera 130 preferably uses a camera suitable for the purpose of target tracking, and the image acquired from the camera 130 for target tracking is left and right for the camera 130 so that it can be utilized as remote coordinate data. It can be implemented as a remote image control application installed on the portable terminal 30 to control rotation and vertical rotation, and this remote image control application can remotely control the left and right rotation and vertical rotation of the camera 130 by itself. This can be done through the interworking of remote programs that make it possible.

As a method of calculating the amount of left and right rotation and vertical rotation control required when controlling the camera 130 so that an arbitrary point on the image of the camera 130, that is, a target T, comes to the center of the image as shown in FIG. 2, In order to bring a specific target target T to the center of the screen, the key is how much left and right rotation and vertical rotation of the camera 130 need to be moved.

The rotation control for the camera 130 simply rotates up and down by dy and rotates left and right by dx, because it is impossible to obtain the results of the usable remote coordinate data, so the camera 130 through the remote image control application. It is necessary to control the left and right rotation and up and down rotation of the .

That is, in the vertical rotation by dy and the left and right rotation control method by dx, the position of the point in the image when the camera 130 is rotated up and down, that is, the target T, with the reason that it changes while drawing a parabolic shape as in FIG. Because there is a reason that the rotation axis changes according to the current vertical rotation value when the camera 130 rotates left and right, it is not possible to obtain a result of usable remote coordinate data.

As shown in FIG. 3, when there is a specific target T on the image, if the camera 130 is rotated up and down in the vertical direction, the specific target T does not move in a straight line along the blue line, but is actually red. It moves in the form of a parabola along the colored line.

That is, like the left triangle, the relationship between the focus (center of the projection) of the camera 130 and the target (T) object is always fixed regardless of the vertical rotation, but only the part cut by the image plane changes as the vertical rotation changes. do. The length of the cut portion determines the x-coordinate, and when the vertical rotation of the camera 130 looks at the target T object in the front, the value becomes the minimum. Also, as the camera 130 looks in another direction, the value increases.

For example, if you consider a quadrangular pyramid, consider that the vertex of the quadrangular pyramid is the camera focus and the bottom is the image plane. . This can be calculated mathematically. If the x-coordinate of the target (T) is dx when the vertical rotation is adjusted so that the target (T) is in the center of the screen in the vertical direction, the x when the camera is rotated vertically by dt at that location. The coordinates are dx/cos(dt).

Next, looking at the effect of left and right rotation according to vertical rotation, if left and right rotation occurs in a state where there is no vertical rotation, the camera screen will move left and right, but if the vertical rotation is 90 degrees (when looking at the ceiling or looking at the floor) ), rotation takes place in a circle with the center of the image as the center. As such, the left/right rotation of the camera produces completely different results depending on the current vertical rotation value, so calculation is always required considering the vertical rotation value.

In the method for moving the camera center to an arbitrary target (T) point on the image, for example, if you do not know the absolute left/right rotation and vertical rotation values of the first camera, basically, if you do not know the current vertical rotation value, in order to go to the corresponding position It is impossible to calculate the amount of movement required at once. The reason is that in the actual camera, the physical rotation axes of left and right rotation and vertical rotation are fixed to one each.

It is possible to calculate the relative left and right rotation angles and vertical rotation angles in the current image, but since the actual physical rotation axis is not in the left and right direction of the current image, the movement amount cannot be calculated if the vertical rotation is not known. If you had a camera that could be rotated in any direction, this would not be a problem.

If you do not know the current vertical rotation value, first rotate left and right by dx or rotate up and down by dy, then calculate the error by grafting the image tracking technology. It may be possible to focus on a single move.

Second, if the absolute horizontal rotation and vertical rotation values of the camera are known, a coordinate system definition is required to derive the formula. Of course, it does not matter if it is defined in a different way, and there may be slight differences in formulas and the like depending on the definition method.

The world geodetic system, for example, has the XY plane on the ground, the upper Z axis, the camera optical axis direction Zc, the right Xc, the lower Yc, and the origin of the camera geodetic system and the origin of the world geodesic system coincide .

In addition, the left and right rotation and vertical rotation of the camera in the global geodetic system can be defined as follows. For example, the left and right rotation is the left and right rotation angle of the camera, and when the optical axis is parallel to the global geodetic Y axis, 0 degrees, the left is +, While the right side is in the - direction, the vertical rotation is the vertical rotation angle of the camera, 0 degrees when the optical axis is parallel to the global geodesic Y axis, the top is +, and the bottom is the - direction.

That is, the left and right rotation and vertical rotation of the camera are 0 when the optical axis Zc of the camera is in the Y-axis direction. Therefore, if the left/right rotation value of the current camera is p, the vertical rotation value is t, and the image coordinate of the target point to be moved is q(x,y), the left/right rotation value p', the vertical rotation value for aligning q to the center of the image t' can be calculated, and if you move the camera to the calculated p', t' position, the current left/right rotation and left/right rotation are p, t. will move

This calculation method is a method of calculating the horizontal and vertical rotation values in the direction of the line after finding a line that forgets the camera focus and target point on the world geodesic coordinate system. Of course, this method can be calculated on the assumption that the focus position of the camera is fixed regardless of left-right rotation or vertical rotation. However, since the actual left-right rotation/up-down rotation also changes the camera focus position, there may be errors.

As described above, as an embodiment of the present invention, a remote coordinate measurement system using a drone system is a drone in a state in which a target tracking camera, a non-target range finder and an encoder sensor capable of angle measurement are mounted on the lower part of the drone. During the flight process of, for example, a drone equipped with a GPS receiver capable of receiving L1 and L2 frequencies, a sensor, and an inertial navigation unit (IMU) maintains precise stationary flight in the air while controlling the coordinates and location information of several centimeters, and the camera and distance It can be obtained by measuring the 3D coordinate image to the target point based on the still flight coordinates of the drone and the distance value data for it by using a measuring device.

Therefore, the accuracy of the secured 3D coordinate image and the remote coordinate data reflecting the distance value data can be guaranteed, and the location of each target point from the ground origin is developed in real time on a CAD or spatial information platform-based screen monitor. It is also possible to improve the general utility of remote coordinate data by visualizing it in this way.

Drone System(10)
Drone 100 GPS Receiver 110
Inertial Navigation System (120) Camera (130)
Distance measuring device (140) Angle measuring sensor (150)
Drone Controller (20) Portable Terminal (30)
Management Server (40)

Claims (5)

delete a drone system that simultaneously measures the distance to the 3D coordinate image in the process of capturing and collecting the 3D coordinate image of the target site remotely through a flying drone; a drone controller for controlling the flight of the drone, and a portable terminal for receiving a 3D coordinate image measured from the drone system from a satellite, and remotely operating a 3D coordinate image of the drone; and a management server for storing coordinate measurement data for the 3D coordinate image transmitted from the portable terminal as a DB or transmitting the DB to the portable terminal in some cases. including,
a camera mounted on the drone to take a 3D coordinate image of the target site during a stationary flight process of the drone; and a distance measuring device mounted on the drone to obtain distance value data for the 3D coordinate image by calculating distance value data in a manner that calculates a time difference between sound waves and a distance to a target site. further comprising,
The range finder includes: a sonar for calculating distance value data in a manner that calculates a time difference between sound waves transmitted from a fixed sound wave detection system built in a target site; and a beacon receiver for discriminating corresponding distance value data of individual sound waves transmitted from the sound wave detection system in a manner of receiving individual signals of beacon; further comprising,
During low-altitude flight of the drone at the target site, the sonar sensor of the distance measuring instrument grafted to the drone is a sound wave detection system that is fixedly installed on the target site. As the beacon receiver receives the individual signals of beacons as the sound wave detection system, it distinguishes the corresponding distance value data calculated by the time difference of the sound waves transmitted from the sound wave oscillators combined with the beacons, and the congestion sound mixed with the sound wave is A remote coordinate measurement system using a drone system, characterized in that it is removed by a filter, and the waveforms of the sound wave are distinguished by an envelope detector. 3. The method of claim 2,
A remote coordinate measurement system using a drone system, characterized in that an encoder sensor is used as an angle measuring sensor that accurately detects a rotation angle in the rotation operation process of the camera. delete 4. The method of claim 3,
For universal utility as remote coordinate data for the 3D coordinate image acquired from the camera, control of left and right rotation and vertical rotation of the camera is performed remotely through a remote image control application installed in the portable terminal, characterized in that A remote coordinate measurement system using a drone system.

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