CN111510624A - Target tracking system and target tracking method - Google Patents

Abstract

The invention discloses a target tracking system and a target tracking method. The method includes the following steps: obtaining the target position information of the target object being tracked; determining the current angle information of the PTZ, the horizontal tilt angle of the PTZ relative to the horizontal position, the position information of the mobile device and the heading angle information; processing through a data processing module , determine the distance information between the mobile device and the tracked target object, the horizontal azimuth angle and the pitching mechanical angle that the gimbal module needs to rotate; send the horizontal azimuth and pitching mechanical angle to the gimbal controller, and the gimbal controller controls the gimbal The module is rotated to a corresponding angle, so that the camera is aimed at the tracked target object; the distance information is sent to the mobile control module, and the mobile control module controls the mobile device to maintain the corresponding distance from the tracked target object.

Description

Target tracking system and target tracking method

technical field

The invention relates to a target tracking system and a corresponding target tracking method, and belongs to the technical field of satellite navigation.

Background technique

At present, with the development of artificial intelligence and image processing technology, the target tracking system based on image recognition has been widely used. This object tracking system is a good solution for tracking shooting. However, in some scenarios, this image recognition-based target tracking system has natural defects. For example, after a moving target is blocked by an obstacle for a period of time, the target tracking system based on image recognition is likely to lose the target and cannot continue to track and shoot the target.

SUMMARY OF THE INVENTION

The primary technical problem to be solved by the present invention is to provide a target tracking system.

Another technical problem to be solved by the present invention is to provide a target tracking method.

In order to achieve the above object, the present invention adopts the following technical scheme:

According to a first aspect of the embodiments of the present invention, a target tracking system is provided, including a GNSS positioning device, a wireless communication device, and a mobile device; the mobile device includes a data processing module, a movement control module, a positioning and orientation module, and a pan-tilt module; The pan-tilt module includes a photoelectric encoder, a level, a pan-tilt controller and a camera;

The GNSS positioning device is arranged on the tracked target object, and is used to obtain the target position information of the tracked target object in real time, and is connected with a mobile device through a wireless communication device, and sends the target position information to the mobile device;

The mobile device determines the current angle information of the gimbal through the photoelectric encoder of the gimbal module, determines the horizontal inclination angle of the gimbal relative to the horizontal position through the level of the gimbal module, and determines the position information and heading angle information of the mobile device through the positioning and orientation module. , through the data processing module to process the target position information, the current angle information of the PTZ, the horizontal tilt angle, the position information of the mobile device and the heading angle information to determine the distance information between the mobile device and the tracked target object, and the PTZ module needs The rotated horizontal azimuth and pitching mechanical angle; the horizontal azimuth and pitching mechanical angle are sent to the pan-tilt controller in the pan-tilt module through the data processing module, and the pan-tilt controller controls the pan-tilt module to rotate to the corresponding angle, so that The camera is aimed at the tracked target object; the distance information is sent to the movement control module through the data processing module, and the movement control module controls the mobile device to maintain a corresponding distance from the tracked target object.

Preferably, the GNSS positioning device is arranged on the target object to be tracked.

Preferably, the positioning and orientation module is a dual-antenna GNSS positioning and orientation structure; the baseline of the mobile device is determined by a straight line vector between two antennas in the dual-antenna GNSS positioning and orientation structure, so that the baseline of the mobile device and the mobile device The central axis of the PTZ is parallel and passes through the center of the PTZ module.

According to a second aspect of the embodiments of the present invention, a target tracking method is provided, which is implemented based on the above-mentioned target tracking system; the method includes the following steps:

Obtain the target position information of the tracked target object in real time, and send the target position information to the mobile device;

Determine the current angle information of the gimbal through the photoelectric encoder;

Determine the horizontal inclination angle of the gimbal relative to the horizontal position through a spirit level;

Determine the position information and heading angle information of the mobile device through the positioning and orientation module;

Process the target position information, the current angle information of the gimbal, the horizontal tilt angle, the position information of the mobile device and the heading angle information, and determine the distance information between the mobile device and the tracked target object, and the horizontal azimuth angle that the gimbal module needs to rotate. and pitch mechanical angle;

Send the horizontal azimuth angle and the pitch mechanical angle to the pan-tilt controller, and the pan-tilt controller controls the pan-tilt module to rotate to the corresponding angle, so that the camera is aimed at the tracked target object;

The distance information is sent to a movement control module, and the movement control module controls the mobile device to maintain a corresponding distance from the tracked target object.

Preferably, the location information of the mobile device includes: the altitude H1 of the mobile device, the latitude Lat1 of the mobile device, and the longitude Lng1 of the mobile device;

The target location information includes: the altitude H2 of the tracked target object, the latitude Lat2 of the tracked target object, and the longitude Lng2 of the tracked target object;

The heading angle information includes: heading angle ∠N of the mobile device.

Preferably, the mobile device adopts the following formula to determine the horizontal azimuth Az that the pan-tilt module needs to rotate:

Preferably, the mobile device uses the following formula to determine the distance information D between the mobile device and the tracked target object:

where π is the pi and R is the radius of the earth.

Preferably, the mobile device adopts the following formula to determine the mechanical pitch angle E1 that the gimbal module needs to rotate:

Among them, ∠M is the horizontal tilt angle.

In the target tracking system and method provided by the present invention, the horizontal inclination angle of the gimbal relative to the horizontal position is determined by the level of the gimbal module, and the heading angle information is determined through the positioning and orientation module, so that when calculating the horizontal azimuth later, the heading The angle information is added to the calculation scheme. When calculating the pitching mechanical angle later, the horizontal tilt angle is added to the calculation scheme, so that the calculation of the horizontal azimuth and pitching mechanical angle required to control the gimbal module is more accurate. At the same time, the present invention can also determine the distance information between the mobile device and the tracked target object, so that the mobile device and the tracked target object can maintain the corresponding distance, realize the precise control of the target tracking, and the effect of shooting the tracked target object is better. good.

Description of drawings

1 is a schematic structural diagram of a target tracking system provided by an embodiment of the present invention;

2 is a schematic diagram of the positional relationship of a mobile device, a pan-tilt module, and a dual-antenna GNSS positioning and orientation structure in an embodiment of the present invention;

3 is a schematic diagram of a geometric relationship between a mobile device and a tracked target object in an embodiment of the present invention;

FIG. 4 is a flowchart of a target tracking method provided by an embodiment of the present invention.

Detailed ways

The technical content of the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

At present, the intelligent target tracking system based on the global navigation satellite system (Global Navigation Satellite System, referred to as GNSS) positioning coordinate solution can calculate the horizontal and vertical target angles between two points according to the satellite positioning information of the two points, and the PTZ control The camera is deflected to the corresponding target angle, so as to achieve the effect of tracking the shooting target. However, the intelligent target tracking system has many problems: First, the target angle controlled by the system to deflect the gimbal is inaccurate, and the system does not have the ability to orient and measure its own horizontal tilt angle. According to the satellite positioning information of two points, the system can only The horizontal and vertical angles between the two points are calculated, and the horizontal target angle is calculated with the earth as the reference system and the north pole as the azimuth of 0 degrees. In actual use, the 0-degree angle of the gimbal machine is generally random relative to the north pole. The horizontal target angle is only correct when the gimbal machine's 0-degree angle is parallel to the earth's north pole. The system calculates the vertical target angle by default, and the system is in a horizontal state, so the obtained vertical target angle is only correct when the gimbal is in an absolutely horizontal state. Second, the system does not have the ability to move. When facing a shooting target with a large moving range, the system may not be able to clearly shoot long-distance targets and meet complex shooting needs.

In order to overcome the above problems, as shown in FIG. 1 , an embodiment of the present invention provides a target tracking system. The target tracking system 10 includes: a GNSS positioning device 11 , a wireless communication device 12 and a mobile device 13 .

The mobile device 13 includes a data processing module 131 , a movement control module 132 , a positioning and orientation module 133 and a pan-tilt module 134 ;

The GNSS positioning device 11 is set on the tracked target object 20 to obtain the target position information of the tracked target object 20 in real time, and realizes communication connection with the mobile device 13 through the wireless communication device 12, and sends the target to the mobile device 13. location information.

The mobile device 13 determines the current angle information of the gimbal through the photoelectric encoder 1341 of the gimbal module 134; determines the horizontal tilt angle of the gimbal relative to the horizontal position through the level 1342 of the gimbal module 134; determines the position information of the mobile device through the positioning and orientation module 133 and heading angle information; through the data processing module 131, the target position information, the current angle information of the PTZ, the horizontal tilt angle, the position information of the mobile device and the heading angle information are processed to determine the distance information between the mobile device 13 and the tracked target object 20 , the horizontal azimuth and the pitching mechanical angle that the pan-tilt module 134 needs to rotate; the horizontal azimuth and the pitching mechanical angle are sent to the pan-tilt controller 1343 in the pan-tilt module 134 through the data processing module 131, so that the pan-tilt controller 1343 The control pan-tilt module 134 uses the horizontal azimuth angle and the tilting mechanical angle to rotate to the corresponding angle, so that the camera 1344 is aimed at the tracked target object 20; the distance information is sent to the movement control module 132 through the data processing module 131, so that the movement control The module 132 controls the mobile device 13 to maintain a corresponding distance with the tracked target object 20, so that precise control of the target tracking can be achieved, and since the corresponding distance can be maintained, the changes in the focusing parameters of the camera are small, and the tracked target object is photographed. better effect.

Here, the movement control module 132 controls the mobile device 13 to maintain a corresponding distance from the tracked target object 20, which can be achieved in the following manner:

Wherein, the movement control module 132 may include a PID (Proportional Integral Derivative) control module, a driver, a servo motor and other structures. In this way, after the distance information is sent to the movement control module 132, the PID control module can run the PID control algorithm and output a speed command to the driver. The driver outputs a certain duty cycle PWM (pulse width modulation) wave current to the servo motor according to the speed command to control the speed of the servo motor. The servo motor drives the transmission mechanism of the mobile device to move the mobile device. The application of PID control algorithm makes the movement control of mobile devices more accurate and convenient.

Wherein, the GNSS positioning device 11 is set on the tracked target object 20 on the ground. The positioning and orientation module 133 is disposed at the mobile device 13 on the ground, and the mobile device 13 on the ground may refer to a ground mobile carrying device such as a four-wheel vehicle or a crawler vehicle. The embodiments of the present invention are generally aimed at ground shooting targets. In order to make the target tracking accurate, the positioning and orientation module 133 can adopt the GNSS positioning and orientation module based on real-time dynamic RTK (Real-Time Kinematic) technology. The accuracy is within 0.3 degrees, it can be seen that the positioning accuracy based on RTK technology is relatively high, which can fully meet the positioning requirements of the present invention for target tracking.

In addition, as shown in FIG. 2, the positioning and orientation module 133 can use a dual-antenna GNSS positioning and orientation mechanism, including antenna A and antenna B); The straight line vector between B) is determined so that the baseline of the mobile device 13 is parallel to the central axis of the mobile device 13 and passes through the center of the pan-tilt module 134 . For example, in FIG. 2 , two antennas (Antenna A and Antenna B) are arranged on the central axis of the mobile device 13 , the straight line vector formed by them is the baseline of the mobile device 13 , and the vector direction is from the tail of the mobile device 13 to the head (e.g. the rear of the car points to the front of the car). The pan/tilt module 134 is mounted on the mobile device 13 on the ground, and it can be in the shape of a disk, and the center of the circle can be on the base line of the mobile device 13 . The horizontal mechanical angle calibration range of the pan/tilt module 134 is 0°～360°, the two intersection points of the pan/tilt module 134 and the baseline of the mobile device 13 are respectively set as mechanical azimuth 0° and 180°, and the pitch mechanical angle calibration range is -90° °～90°, the position relative to the baseline level is set as 0 degrees of the pitching machine.

The wireless communication device 12 in the embodiment of the present invention may be a device with a function of wirelessly transmitting data, such as a Bluetooth device, a WiFi (wireless Internet access) device, or a Narrow Band Internet of Things (NB-IoT) device. It can be seen that the wireless communication modes of the present invention are various, so that the communication environment adapted to the target tracking in the embodiment of the present invention is more diverse.

In addition, in this embodiment of the present invention, the location information of the mobile device may include: the altitude H1 of the mobile device, the latitude Lat1 of the mobile device, and the longitude Lng1 of the mobile device; the target location information may include: the altitude H2 of the tracked target object, the tracked target The object latitude Lat2 and the tracked target object longitude Lng2; the heading angle information may include: the heading angle ∠N of the mobile device.

Wherein, in the embodiment of the present invention, the mobile device 13 can specifically determine the horizontal azimuth Az that needs to be rotated by the pan-tilt module through the data processing module using the following formula:

Since the heading angle ∠N of the mobile device is used as a factor in the calculation of the horizontal azimuth angle Az, compared with the horizontal azimuth angle obtained without considering the influence of the heading angle ∠N of the mobile device, the horizontal azimuth angle Az is closer to the actual situation and more accurate.

In order to express the solution process of the horizontal azimuth Az more intuitively, as shown in Figure 3, A is the position of the mobile device, B is the position of the tracked target object, E and F are the distances of points A and B on the equatorial plane, respectively. map. O is the center of the earth, and C is the north pole of the earth. D is the spherical distance between two points AB. Obtain the location information of A according to GNSS positioning: longitude Lng1, latitude Lat1, and height H1. The position information of the tracked target object B is longitude Lng2, latitude Lat2, and height H2.

Finding the horizontal azimuth, that is, the azimuth of point B relative to point A, is equivalent to finding the dihedral angle C-OA-B.

According to the trihedral cosine theorem, we can get

cos(∠AOB)=cos(∠AOC)cos(∠BOC)+sin(∠AOC)sin(∠BOC)cos(∠A-OC-B);

From the definition of longitude, ∠AOE=Lat1, ∠BOF=Lat2, so ∠AOC=90-∠AOC=90°-Lat1, ∠BOC=90°-∠BOC=90°-Lat2;

∠A-OC-B is equivalent to the angle between the two points A and B that map the two points EF on the equatorial plane, that is, ∠EOF. According to the definition of longitude, ∠EOF=Lng2-Lng1, so ∠A-OC-B=∠EOF=Lng2-Lng1.

Bring in the coordinate data, you can get:

cos(∠AOB)=cos(90°－Lat1)×cos(90°－Lat2)+sin(90°－Lat1)×sin(90°－Lat2)×cos(Lng2－Lng1);

According to the trigonometric function formula sin(∠AOB)=sqrt(1–cos2(∠AOB)); sqrt represents the operation of the square root.

From the spherical sine formula, sin(∠C-OA-B)=sin(∠BOC)sin(A-OC-B)/sin(∠AOB);

So ∠C-OA-B=arcsin(sin(∠BOC)sin(A-OC-B)/sin(∠AOB))

Bringing in the known results above, we get:

In addition, in the embodiment of the present invention, the mobile device 13 can specifically determine the distance information D between the mobile device and the tracked target object by using the following formula through the data processing module:

where π is the pi and R is the radius of the earth.

That is, for example, in the above-mentioned FIG. 3 , the distance D=R*rad(∠AOB) of the spherical surface AB.

The formula is:

Where R is the radius of the earth, for example: R = 6371393 meters, π is the pi: π = 3.1415926535898.

In addition, in the embodiment of the present invention, the mobile device 13 can specifically use the data processing module to determine the pitch mechanical angle E1 that the pan-tilt module needs to rotate by using the following formula:

Among them, ∠M is the horizontal tilt angle.

Since the horizontal inclination angle ∠M is used as a factor in the calculation of the pitching mechanical angle E1, the pitching mechanical angle E1 is closer to the pitching mechanical angle obtained without considering the influence of the horizontal inclination angle ∠M. The actual situation is more accurate.

In addition, an embodiment of the present invention further provides a target tracking method, which is implemented based on the target tracking system shown in FIG. 1 . The target tracking system includes a GNSS positioning device, a wireless communication device and a mobile device; the mobile device includes a data processing module, a mobile control module, a positioning and orientation module, and a pan-tilt module; the pan-tilt module includes a photoelectric encoder, a level, a pan-tilt controller and Camera; GNSS positioning device is set on the target object being tracked.

As shown in Figure 4, the target tracking method includes the following steps:

Step 301: Obtain target position information of a tracked target object in real time, and send the target position information to a mobile device.

Step 302: Determine the current angle information of the gimbal by using the photoelectric encoder.

Step 303: Determine the horizontal inclination angle of the gimbal with respect to the horizontal position by using a spirit level.

Step 304: Determine the location information and heading angle information of the mobile device through the positioning and orientation module.

Step 305: Process the target position information, the current angle information of the gimbal, the horizontal tilt angle, the position information of the mobile device and the heading angle information, and determine the distance information between the mobile device and the tracked target object, and the horizontal azimuth that the gimbal module needs to rotate. angle and pitch mechanical angle.

Step 306: Send the horizontal azimuth angle and the pitching mechanical angle to the gimbal controller in the gimbal module, and the gimbal controller controls the gimbal module to rotate to a corresponding angle, so that the camera is aimed at the tracked target object.

Step 307: Send the distance information to the mobile control module, and the mobile control module controls the mobile device to maintain a corresponding distance from the tracked target object.

Wherein, the location information of the mobile device includes: the altitude H1 of the mobile device, the latitude Lat1 of the mobile device, and the longitude Lng1 of the mobile device; the target location information includes: the altitude H2 of the tracked target object, the latitude Lat2 of the tracked target object, and the tracked target The longitude of the object Lng2; the heading angle information includes: the heading angle ∠N of the mobile device.

Wherein, in the above step 305, the mobile device determines the horizontal azimuth angle that the pan-tilt module needs to rotate through the data processing module, which can be implemented in the following manner:

The mobile device uses the following formula to determine the horizontal azimuth Az that the pan-tilt module needs to rotate through the data processing module:

Wherein, in the above step 305, the mobile device determines the distance information between the mobile device and the tracked target object through the data processing module, which can be implemented in the following manner:

The mobile device uses the following formula to determine the distance information D between the mobile device and the tracked target object through the data processing module:

where π is the pi and R is the radius of the earth.

Wherein, in the above step 305, the mobile device determines, through the data processing module, the pitching mechanical angle that the pan-tilt module needs to rotate, which can be implemented in the following manner:

Through the data processing module, the mobile device adopts the following formula to determine the mechanical pitch angle E1 that the gimbal module needs to rotate:

Among them, ∠M is the horizontal tilt angle.

In addition, an embodiment of the present invention further provides a computer-readable storage medium, where instructions are stored on the readable storage medium, and when the readable storage medium is run on a computer, the computer is made to execute the above-mentioned target tracking method, which is not described here. Repeat.

In addition, an embodiment of the present invention also provides a computer program product including instructions, which, when running on a computer, enables the computer to execute the above-mentioned target tracking method, which will not be repeated here.

In the target tracking system and method provided by the present invention, the horizontal inclination angle of the gimbal relative to the horizontal position is determined by the level of the gimbal module, and the heading angle information is determined through the positioning and orientation module, so that when calculating the horizontal azimuth later, the heading The angle information is added to the calculation scheme. When calculating the pitching mechanical angle later, the horizontal tilt angle is added to the calculation scheme, so that the calculation of the horizontal azimuth and pitching mechanical angle required to control the gimbal module is more accurate. At the same time, the present invention can also determine the distance information between the mobile device and the tracked target object, so that the mobile device and the tracked target object can maintain the corresponding distance, realize the precise control of the target tracking, and the effect of shooting the tracked target object is better. good.

The target tracking system and the target tracking method provided by the present invention have been described in detail above. For those skilled in the art, any obvious changes made to it without departing from the essential content of the present invention will fall into the protection scope of the patent right of the present invention.

Claims (8)

1. A target tracking system comprising a GNSS positioning apparatus, a wireless communication apparatus and a mobile apparatus; the mobile device comprises a data processing module, a mobile control module, a positioning and orientation module and a holder module; the holder module comprises a photoelectric encoder, a level meter, a holder controller and a camera;

the GNSS positioning device is arranged on a tracked target object and is used for acquiring target position information of the tracked target object in real time, connecting the GNSS positioning device with a mobile device through a wireless communication device and sending the target position information to the mobile device;

the mobile device determines the current angle information of the holder through a photoelectric encoder of the holder module; determining a horizontal inclination angle of the holder relative to a horizontal position through a level gauge of the holder module; determining position information and course angle information of the mobile device through a positioning and orientation module; processing the target position information, the current angle information of the holder, the horizontal inclination angle, the position information of the mobile device and the course angle information through a data processing module, and determining the distance information between the mobile device and a tracked target object, and the horizontal azimuth angle and the pitching mechanical angle of the holder module which need to rotate; sending the horizontal azimuth angle and the pitching mechanical angle to a pan-tilt controller in a pan-tilt module through a data processing module, wherein the pan-tilt controller controls the pan-tilt module to rotate to a corresponding angle, so that a camera is aligned to a tracked target object; and sending the distance information to a mobile control module through a data processing module, wherein the mobile control module controls the mobile device to keep a corresponding distance with the tracked target object.

2. The target tracking system of claim 1, wherein:

the GNSS positioning apparatus is disposed on a target object to be tracked.

3. The target tracking system of claim 1, wherein:

the positioning and orientation module is a double-antenna GNSS positioning and orientation structure; the baseline of the mobile device is determined by a linear vector between two antennas in the dual-antenna GNSS positioning and orienting structure, so that the baseline of the mobile device is parallel to the central axis of the mobile device and passes through the center of the holder module.

4. A target tracking method is realized based on the target tracking system of any one of claims 1 to 3, and is characterized by comprising the following steps:

obtaining target position information of a tracked target object in real time and sending the target position information to the mobile device;

determining the current angle information of the holder through a photoelectric encoder;

determining a horizontal inclination angle of the holder relative to a horizontal position through a level meter;

determining position information and course angle information of the mobile device through a positioning and orientation module;

processing the target position information, the current angle information of the holder, the horizontal inclination angle, the position information of the mobile device and the course angle information, and determining the distance information between the mobile device and the tracked target object, the horizontal azimuth angle and the pitching mechanical angle of the holder module needing to rotate;

sending the horizontal azimuth angle and the pitching mechanical angle to a holder controller, and controlling a holder module to rotate to a corresponding angle by the holder controller so that a camera is aligned to a tracked target object;

and sending the distance information to a mobile control module, wherein the mobile control module controls the mobile device to keep a corresponding distance with the tracked target object.

5. The object tracking system of claim 1 or the object tracking method of claim 4, characterized in that:

the mobile device location information includes a mobile device altitude H1, a mobile device latitude L at1, and a mobile device longitude L ng 1;

the target position information comprises a tracked target object altitude H2, a tracked target object latitude L at2 and a tracked target object longitude L ng 2;

the heading angle information includes a heading angle ∠ N of the mobile device.

6. The object tracking system of claim 1 or the object tracking method of claim 4, characterized in that:

the mobile device adopts the following formula to determine the horizontal azimuth Az of the cradle head module needing to rotate:

7. the object tracking system of claim 1 or the object tracking method of claim 4, characterized in that:

the mobile device determines distance information D of the mobile device and the tracked target object by adopting the following formula:

wherein, pi is the circumference ratio, and R is the radius of the earth.

8. The object tracking system of claim 1 or the object tracking method of claim 4, characterized in that:

the moving device adopts the following formula to determine the mechanical pitching angle El of the pan-tilt module, which needs to rotate:

wherein ∠ M is a horizontal inclination angle.

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