CN111766902B - Control method for realizing video pan-tilt steering based on longitude and latitude coordinates - Google Patents

Abstract

The invention relates to a control method for realizing the steering of a video cloud deck based on longitude and latitude coordinates, wherein a system acquires the longitude and latitude coordinates of a target object in real time, and executes the conversion of the longitude and latitude coordinates and the synchronous calculation of a steering angle of video equipment, and the system transmits the calculated azimuth angle to a video cloud deck control steering data interface in real time to realize the accurate steering of a video lens, thereby realizing the real-time video observation and the following positioning shooting of the target object by the system. The invention is suitable for real-time tracking observation of objects travelling on water surface and road surface, can measure and calculate the distance of the target object in real time, can realize measures such as accurate strong light irradiation, acoustic wave directional driving and the like on the target object by carrying different directional observation equipment on the holder, and has wide application prospect.

Description

Control method of video pan/tilt steering based on latitude and longitude coordinates

technical field

The invention relates to the field of intelligent monitoring of submarine cable channels, in particular to a control method for realizing video pan/tilt steering based on longitude and latitude coordinates.

Background technique

In the field of anti-external force damage monitoring of submarine cables in the power industry, the most commonly used technical means is to use ship positioning system (AIS) and video equipment to monitor suspicious targets in the water surface area where the submarine cable is located. The approximate orientation of the suspicious target (mainly ships), and then manually adjust the video device with the gimbal to turn to the target orientation, so as to realize the video monitoring of the suspicious target. Although this method can achieve the purpose of video surveillance of suspicious targets, the degree of intelligence and effectiveness is not high, and it cannot achieve target location point ranging. Due to the complex environment of the submarine cable channel area, the operation of manually adjusting video alignment is disturbing. It is very important to be able to detect and deal with the risk of external breakage in the submarine cable channel area at the first time. If the target location is inaccurate and the emergency measures are improperly handled, it will cause the submarine cable breakout accident and power supply interruption, and cause social and economic property. loss. Therefore, if the automatic and precise video steering and video forensics can be realized through intelligent technical means, and the reference distance of suspicious targets can be calculated at the same time, the detection rate and timely rate of suspicious targets on the submarine cable site will be effectively improved, and the status of submarine cables will be further improved. Judgment, accident prevention and emergency response provide favorable conditions, thereby contributing to the improvement of the intelligent level of submarine cable operation and maintenance.

SUMMARY OF THE INVENTION

In view of this, the purpose of the present invention is to provide a control method for realizing video pan/tilt steering based on latitude and longitude coordinates, which can realize automatic precise steering and ranging of video equipment through automatic calculation of the system, which can reduce the complexity of video operations for operation and maintenance personnel. to improve the efficiency of emergency response.

To achieve the above object, the present invention adopts the following technical solutions:

A control method for realizing video pan/tilt steering based on longitude and latitude coordinates, comprising the following steps:

Step S1: obtain the latitude and longitude coordinates and the altitude of the photoelectric device with the PTZ, and build an initial coordinate system, and use the latitude and longitude sum as its origin coordinates (x, y, z);

Step S2: Obtain the initial horizontal angle and vertical angle of the photoelectric device with the gimbal, set the horizontal starting angle of the gimbal as an angle of 0 degrees, and its side length coincides with the positive direction of the X-axis of the horizontal coordinate system; The vertical starting angle is set as an angle of 0 degrees, and its side length coincides with the X-axis direction of the vertical coordinate system; the difference between the initial angle of the optoelectronic device and the preset starting angle in the system is the deviation angle α;

Step S3: obtain the relevant data of the target, and calculate the horizontal distance and the steering angle between the target and the photoelectric device;

Step S4: by calling the data control interface of the optoelectronic device, and according to the horizontal distance and the steering angle between the target object and the optoelectronic device, the precise steering of the optoelectronic device to the target object is controlled;

Step S5: After completing the steering control, reset the current steering angle of the photoelectric device pan/tilt to the initial angle of the photoelectric device, and simultaneously record the deviation angle of the difference between the initial angle and the initial angle.

Further, the step S3 is specifically as follows: the latitude and longitude coordinate values (LonA, LatA) of the target object, the average radius R of the earth, the distance _1WD between each latitude, and the application scene are located at the equator and are obtained by receiving the maritime radar and the ship positioning device. Northern and Eastern Hemispheres.

Further, the calculation of the horizontal distance between the target and the optoelectronic device is as follows:

1) Determine the coordinate quadrant of the target object: Calculate the coordinate quadrant of the target object according to the longitude and latitude of the target object (LonA, LatA) and the longitude and latitude of the origin (LonO, LatO):

In the first quadrant of coordinates: LonA-LonO>0 and LatA-LatO>0;

In the second quadrant of coordinates: LonA-LonO<0 and LatA-LatO>0;

In the 3rd quadrant of coordinates: LonA-LonO<0 and LatA-LatO<0;

In the fourth quadrant of coordinates: LonA-LonO>0 and LatA-LatO<0;

2) Calculate the straight-line distance between the target and the origin:

Calculate the horizontal straight-line distance l _AO between the target and the origin:

First calculate the north-south distance and east-west distance between the two,

North-South distance: l _W'D' =|LatA-LatO|*l _WD ,

East-west distance: l _J'D' = |LonA-LonO|*COS|LatA-LatO|*l _WD ,

In the horizontal coordinate system, the straight-line distance l _AO between the target and the origin forms a right triangle with l _W'D' and l _J'D' , where l _AO is the hypotenuse and l _J'D' is the adjacent side , l _W'D' is the opposite side, then the length of l _AO can be calculated by the Pythagorean theorem, namely

Further, the steering angle includes a horizontal steering angle and a vertical angle.

Further, the calculation of the horizontal steering angle between the target and the optoelectronic device is specifically:

According to the horizontal rectangular coordinate quadrant of the target object and the distance between the target object and the origin, the angle formed by the target object and the origin on the horizontal rectangular coordinate system and the positive direction of the X axis is:

The target is in the first quadrant, and the angle with the origin is: θ=arctg(l _W'D' /l _j'D' )+0×π;

The target is in the second quadrant, and the angle to the origin is:

The target is in the third quadrant, and the angle to the origin is:

The target is in the 4th quadrant, and the angle to the origin is:

Further, the calculation of the vertical steering angle between the target and the optoelectronic device is as follows:

(1) Judging the quadrant of the coordinates of the target object:

(2) Obtain the straight-line distance and the vertical distance between the target and the origin, the installation height of the photoelectric device above sea level is the vertical distance h _AO between the target and the origin, and the straight-line distance between the two is l _AO ;

(3) Calculate the vertical angle between the target and the origin according to the straight-line distance and the vertical distance between the target and the origin.

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

The invention realizes automatic and precise steering and ranging of video equipment through automatic calculation of the system, which can reduce the complexity of video operation for operation and maintenance personnel and improve the efficiency of emergency response.

Description of drawings

Fig. 1 is the accurate steering process flow chart of photoelectric equipment of the present invention;

FIG. 2 is a schematic diagram of the main components of an optoelectronic device in an embodiment of the present invention;

Fig. 3 is the video horizontal steering scene model in the horizontal Cartesian coordinate system in one embodiment of the present invention;

4 is a video vertical steering scene model in a vertical rectangular coordinate system in an embodiment of the present invention;

FIG. 5 is a schematic diagram of a horizontal steering positioning process of an optoelectronic device in an embodiment of the present invention;

FIG. 6 is a schematic diagram of a vertical steering positioning process of an optoelectronic device in an embodiment of the present invention.

Detailed ways

The present invention will be further described below with reference to the accompanying drawings and embodiments.

Please refer to FIG. 1 , the present invention provides a control method for realizing video pan/tilt steering based on latitude and longitude coordinates, comprising the following steps:

Step S1: obtain the latitude and longitude coordinates and the altitude of the photoelectric device with the PTZ, and build an initial coordinate system, and use the latitude and longitude sum as its origin coordinates (x, y, z);

As shown in Fig. 3, in this embodiment, the absolute longitude and latitude coordinates of any monitored object are converted into coordinate positions (x', y') relative to the origin. The purpose of establishing the horizontal coordinate system is to calculate the distance of the target from the origin and the horizontal rotation angle of the optoelectronic device from the initial position to the target position.

As shown in Figure 4, in the embodiment, any monitored object is considered to be located on the horizontal plane (height: 0 meters), and the horizontal distance between the target and the optoelectronic device and the known altitude-to-ground distance of the optoelectronic device can be calculated. The vertical angle at which the optoelectronic device rotates toward the target.

Step S2: Obtain the initial horizontal angle and vertical angle of the photoelectric device with the gimbal, set the horizontal starting angle of the gimbal as an angle of 0 degrees, and its side length coincides with the positive direction of the X-axis of the horizontal coordinate system; The vertical starting angle is set to 0 degree angle, and its side length coincides with the X-axis direction of the vertical coordinate system; the difference between the initial angle of the optoelectronic device and the preset starting angle in the system is the deviation angle α; as shown in Figure 3 As shown in Figure 4, it is assumed that the initial angles of the video equipment are in the first quadrant in the Cartesian coordinate system

Step S3: obtain the relevant data of the target, and calculate the horizontal distance and the steering angle between the target and the photoelectric device;

In this embodiment, the latitude and longitude coordinate values (LonA, LatA) of the target object are obtained by receiving from maritime radar and ship positioning equipment; the application scenario is located north of the equator (north latitude) and eastern hemisphere (east longitude).

Horizontal distance and horizontal steering angle calculation process:

1) Determine the coordinate quadrant of the target object: Calculate the coordinate quadrant of the target object according to the longitude and latitude of the target object (LonA, LatA) and the longitude and latitude of the origin (LonO, LatO):

In the first quadrant of coordinates: LonA-LonO>0 and LatA-LatO>0

In the 2nd quadrant of coordinates condition: LonA-LonO<0 and LatA-LatO>0

In the 3rd quadrant of coordinates: LonA-LonO<0 and LatA-LatO<0

In the 4th quadrant of coordinates: LonA-LonO>0 and LatA-LatO<0

As shown in Figure 5, it is assumed that the target is in the second quadrant.

2) Calculate the straight-line distance between the target and the origin:

To calculate the horizontal straight-line distance _{l AO} between the target and the _origin , it is necessary to first calculate the north-south distance and the east-west distance between them. Method: l _J'D' = |LonA-LonO|*COS|LatA-LatO|*l _WD , at this time in the horizontal coordinate system of the system, the linear distance between the target and the origin l _AO , and l _{W'D '} , l _J'D' form a right triangle, where l _AO is the hypotenuse, l _J'D' is the adjacent side, and l _W'D' is the opposite side, then the length of l _AO can be calculated by the Pythagorean theorem out, that is

3) Calculate the horizontal angle between the target and the origin:

Knowing the horizontal rectangular coordinate quadrant of the target object and the distance between the target object and the origin, the calculation method of the angle formed by the target object and the origin on the horizontal rectangular coordinate system and the positive direction of the X axis is:

The target is in the first quadrant, and the angle with the origin is: θ=arctg(l _W'D' /l _J'D' )+0×π.

The target is in the second quadrant, and the angle to the origin is:

The target is in the third quadrant, and the angle to the origin is:

The target is in the 4th quadrant, and the angle to the origin is:

As shown in Figure 5, since the target is assumed to be in the second quadrant, the angle of the target is taken as

Preferably, in this embodiment, it is also necessary to consider the relationship between the horizontal deviation angle (α) of the optoelectronic device and the angle (θ) between the target and the origin, as well as the selection of the horizontal steering of the optoelectronic device, so that the optoelectronic device can be turned with the shortest path. To the specified angle:

If θ-α>0 and ≤180, the horizontal deflection angle of the optoelectronic device is |θ-α| (turning from right to left, that is, counterclockwise);

If θ-α<0, the horizontal deflection angle of the optoelectronic device is -|θ-α| (turning from left to right, that is, clockwise);

If θ-α>180, the horizontal deflection angle of the optoelectronic device is -|360-θ+α| (turning from left to right, ie clockwise).

In Figure 5, the video pan/tilt will rotate counterclockwise from its initial position to an angle of θ-α.

2. Vertical angle calculation process:

1) Determine the coordinate quadrant of the target object:

Since the optoelectronic equipment is installed above the horizontal plane and the monitored target is on the horizontal plane, the target must be located in the 3rd or 4th quadrant on the vertical rectangular coordinate system built in the system. In addition, due to the maximum angle of the video head in vertical steering The range is between 90 degrees and -90 degrees, so the target is in any case in the 4th quadrant in the vertical Cartesian coordinate system, as shown in Figure 6.

2) Calculate the straight-line distance and vertical distance between the target and the origin:

Since the target is on the horizontal plane, the installation height of the photoelectric device above sea level is the vertical distance between the target and the origin (denoted as: h _AO ), and the straight-line distance between the two has been calculated when calculating the horizontal steering angle, that is, : _lAO .

3) Calculate the vertical angle between the target and the origin:

Since the horizontal distance l _AO between the optoelectronic device and the target has been calculated, and the vertical height h _AO of the target is known, the calculation method of the angle formed by the target and the origin on the vertical rectangular coordinate system and the positive direction of the X axis is as follows: :

Because the actual maximum vertical steering angle range of the video equipment is 180, and the actual target position is located in the fourth quadrant of the vertical rectangular coordinate system, the vertical deflection angle θ of the video equipment is taken as: -|90-arcos(h _AO /l _AO )|.

Preferably, this embodiment also considers the relationship between the vertical deviation angle (α) of the optoelectronic device and the angle (θ) between the target and the origin, and the vertical deflection angle of the optoelectronic device is:

If θ-α>0 and ≤90, the vertical deflection angle of the optoelectronic device is |θ-α| (the gimbal turns from bottom to top, which is counterclockwise in the vertical coordinate system);

If θ-α<0 and ≥-90, the vertical deflection angle of the optoelectronic device is -|θ+α| (the gimbal turns from top to bottom, which is clockwise in the vertical coordinate system);

In Figure 6, the video head will rotate clockwise from its initial position to an angle of θ+α.

Step S4: by calling the data control interface of the optoelectronic device, and according to the horizontal distance and the steering angle between the target object and the optoelectronic device, the precise steering of the optoelectronic device to the target object is controlled;

Step S5: After completing the steering control, reset the current steering angle of the photoelectric device pan/tilt to the initial angle of the photoelectric device, and simultaneously record the deviation angle of the difference between the initial angle and the initial angle.

Preferably, referring to FIG. 2 , the optoelectronic device with a gimbal in this embodiment includes a gimbal, a photosensitive unit, a laser lens, a thermal imaging lens, and a visible light lens disposed on the gimbal.

The above descriptions are only preferred embodiments of the present invention, and all equivalent changes and modifications made according to the scope of the patent application of the present invention shall fall within the scope of the present invention.

Claims (6)

1. a control method based on latitude and longitude coordinates to realize video pan-tilt steering, is characterized in that, comprises the following steps: Step S1: obtain the latitude and longitude coordinates and the altitude of the photoelectric device with the PTZ, and build an initial coordinate system, and use this longitude and latitude and altitude as its origin coordinates (x, y, z); Step S2: Obtain the initial horizontal angle and vertical angle of the photoelectric device with the gimbal, set the horizontal starting angle of the gimbal as an angle of 0 degrees, and its side length coincides with the positive direction of the X-axis of the horizontal coordinate system; The vertical starting angle is set as an angle of 0 degrees, and its side length coincides with the X-axis direction of the vertical coordinate system; the difference between the initial angle of the optoelectronic device and the preset starting angle in the system is the deviation angle α; Step S3: obtain the relevant data of the target, and calculate the horizontal distance and the steering angle between the target and the photoelectric device; Step S4: by calling the data control interface of the optoelectronic device, and according to the horizontal distance and the steering angle between the target object and the optoelectronic device, the precise steering of the optoelectronic device to the target object is controlled; Step S5: After completing the steering control, reset the current steering angle of the photoelectric device pan/tilt to the initial angle of the photoelectric device, and simultaneously record the deviation angle of the difference between the initial angle and the initial angle. 2. the control method that realizes video pan-tilt steering based on latitude and longitude coordinates according to claim 1, it is characterized in that, described step S3 is specifically: by maritime radar and ship positioning equipment, receive and obtain target object longitude and latitude coordinate values (LonA, LatA ), the mean radius R of the earth, the distance l _WD between each latitude. 3. the control method that realizes video pan-tilt steering based on longitude and latitude coordinates according to claim 1, is characterized in that, the horizontal distance calculation between described target object and photoelectric equipment, is specifically as follows: 1) Determine the coordinate quadrant of the target object: Calculate the coordinate quadrant of the target object according to the longitude and latitude of the target object (LonA, LatA) and the longitude and latitude of the origin (LonO, LatO): In the first quadrant of coordinates: LonA-LonO>0 and LatA-LatO>0; In the second quadrant of coordinates: LonA-LonO<0 and LatA-LatO>0; In the third quadrant of coordinates: LonA-LonO<0 and LatA-LatO<0; In the fourth quadrant of coordinates: LonA-LonO>0 and LatA-LatO<0; 2) Calculate the straight-line distance between the target and the origin: Calculate the horizontal straight-line distance l _AO between the target and the origin: First calculate the north-south distance and east-west distance between the two, North-South distance: l _W'D' =|LatA-LatO|*l _WD , East-west distance: l _J'D' = |LonA-LonO|*COS|LatA-LatO|*l _WD , Among them, l _WD is the distance between each latitude, in the horizontal coordinate system, the straight line distance l _AO between the target and the origin, and l _W'D' , l _J'D' form a right triangle, where l _AO is the hypotenuse, l _J'D' is the adjacent side, and l _W'D' is the opposite side, then the length of l _AO can be calculated by the Pythagorean theorem, namely

4 . The control method for realizing video pan/tilt steering based on latitude and longitude coordinates according to claim 1 , wherein the steering angle includes a horizontal steering angle and a vertical angle. 5 . 5. the control method that realizes video pan-tilt steering based on longitude and latitude coordinates according to claim 4, is characterized in that, the horizontal steering angle calculation between described target object and photoelectric equipment, is specially: According to the horizontal rectangular coordinate quadrant of the target object and the distance between the target object and the origin, the angle formed by the target object and the origin on the horizontal rectangular coordinate system and the positive direction of the X axis is: The target is in the first quadrant, and the angle with the origin is: θ=arctg(l _W'D' /l _J'D' )+0×π; The target is in the second quadrant, and the angle to the origin is:

The target is in the third quadrant, and the angle to the origin is:

The target is in the 4th quadrant, and the angle to the origin is:

where l _W'D' is the north-south distance, and l _J'D' is the east-west distance. 6. the control method that realizes video pan-tilt steering based on latitude and longitude coordinates according to claim 4, is characterized in that, the vertical steering angle calculation between described target object and photoelectric equipment is specifically: (1) Judging the quadrant of the coordinates of the target object: (2) Obtain the straight-line distance and the vertical distance between the target and the origin, the installation height above sea level of the photoelectric device is the vertical distance h _AO between the target and the origin, and the straight-line distance between the two is l _AO ; (3) Calculate the vertical angle between the target and the origin according to the straight-line distance and the vertical distance between the target and the origin.

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