JPH0843514A - Method and system for tracking moving body - Google Patents

Abstract

PURPOSE:To realize a moving-body tracking system by which unknown positions, speeds and the like of a plurality of target moving bodies are estimated on the basis of observation data from a plurality of sensors. CONSTITUTION:Respective sensors 10 observe the direction or the like of at least one target moving body 40, and the observation data are output to a central processing unit 30. Every console 20 outputs, to the central processing unit 30 and other consoles 20, a command and a message which have been input by every operator 50 through every input device 21. In addition, the output of the central processing unit 30 and messages from the other consoles 20 are displayed on every output device 20. The central processing unit 30 performs an initialization processing operation, an observation data-to-wake correspondence processing operation, a filtering processing operation and a finish-judgment processing operation by means of a processing unit 32. In addition, a processed result is corrected by following the input command of every operator 50, and a message is sent and received.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a moving body tracking system which uses a sensor to estimate an unknown position, speed, etc. of a target moving body from the observation data.

The present invention can be used, for example, in a ship operation management support system.

[0003]

2. Description of the Related Art As a conventional technique of a moving body tracking system for estimating the positions and velocities of a plurality of unknown target moving bodies from the observation data of a plurality of sensors, for example, Japanese Patent Laid-Open No. 64-353
The "trajectory information automatic correlation adjustment system for a multi-radar system" described in Japanese Patent No. 91 is known. According to it, the tracking of the target moving body, that is, the estimation of the position and the speed comprises the following three steps.

(1) Each sensor estimates the track (track) of each moving body from the observation data obtained every moment.

(2) The track groups created by the respective sensors are associated with each other, and the tracks by the respective sensors are extracted for each moving body. This is track-to-track correlation (hereinafter T-
(Abbreviated as T correlation).

(3) Based on the above correlation results, the position and velocity of the moving body are accurately estimated by using, for example, the Kalman filter method using the observation data of the moving body among the observation data of the sensors for each moving body. To do.

Here, in step (1), the process of associating each piece of observation data obtained from each sensor with respect to a plurality of moving bodies with the track of each moving body, that is, the observed track correlation (hereinafter referred to as 0-T correlation). Is omitted. For this, for example, the “target identifying method and its apparatus” described in Japanese Patent Laid-Open No. 4-48285 is known.

[0008]

In the above-mentioned prior art, an active sensor that can observe the direction and distance of the target moving body is assumed as the sensor, and the following problems occur when a passive sensor that observes only the direction is used. Occurs.

(A) In 0-T correlation, since distance information cannot be directly obtained, it is difficult to accurately estimate a track for each moving body, and thus the accuracy of 0-T correlation is deteriorated.

(B) In the TT correlation, since the accuracy of the tracks given by the above-mentioned sensors is poor, it becomes difficult to associate the tracks with each other. For example, when the number of moving objects is N and the number of sensors is M, the maximum possible combination of tracks in the TT correlation is (N
!! ) ** (M-1). here! Is factorial again
* Represents exponentiation. When N or M becomes large, the number of combinations becomes enormous, and it takes a lot of processing time to search for a correct combination among them.

Therefore, a first object of the present invention is to accurately estimate unknown positions, velocities, etc. of a plurality of target moving objects from a plurality of sensors using observation data even in the case of a passive sensor. A moving object tracking method and device capable of

Further, in the above-mentioned conventional technique, (c) a method of automatically processing observation data from a sensor by a computer to track a desired moving body is described, but a method of utilizing judgment of an operator will be described. Has not been done.

In particular, when using a plurality of sensors, there is usually an operator for each sensor. In this case, it is possible to improve the accuracy of the judgment when a plurality of operators cooperate to make a judgment rather than each operator makes a judgment individually.

Therefore, a second object of the present invention is to provide a moving body tracking method and a moving body tracking method which allow a plurality of operators to cooperate with each other to make a judgment and to accurately estimate unknown positions, velocities, etc. of a plurality of target moving bodies. It is to provide a device.

[0015]

In order to achieve the first object, in a moving object tracking method comprising an initialization process, an observation data vs. track correspondence process, a filtering process, and an end determination process, By inputting the observation data such as the azimuth by at least two sensors for at least one target moving body by the digitization process and associating the observation data of each sensor with one of the tracks of the target moving body, The observation data of is composed of the track data of the number of target moving bodies, and at least one set of track set candidates is created, and for each of the created candidates of each track set, each target movement is performed by using the above-mentioned associated observation data. The initial estimated values of the body position and velocity are calculated, and the observation data, such as the trajectory correspondence processing, is used to input the observation data such as the direction of the sensor, and Performs a correlation processing for associating the difference observed data and each track pair candidate, deletes the candidate used without the corresponding to the observation data, the filtering process,
For each track group candidate that remains without being deleted, filtering processing is performed using the observation data associated with the correlation processing, the estimated values of the position and speed of each target moving body are updated, and the end determination processing is performed. , If the number of remaining track set candidates is less than a predetermined number and the expected error of the estimated value of the position and speed of each target moving body is less than a predetermined value, it is determined that tracking has ended, and the above observation data is obtained. Anti-track trace processing,
The filtering process and the end determination process are repeated until the tracking end is determined.

In order to achieve the second object,
In a mobile tracking system having at least one sensor, at least two consoles, and a central processing unit, each sensor and each console are connected to the central processing unit, and each sensor has at least one target. The azimuth of the moving body is observed and the observation data is output to the central processing unit.Each console has an input device such as a mouse and an output device such as a display. Output the message to the central processing unit or other console, and the output device
The output of the central processing unit and messages from other consoles are displayed.The central processing unit has an input buffer, a processing unit, and an output buffer.The input buffer stores the observation data of the sensor, and the processing unit initializes it. Initialization processing, observation data versus track correspondence processing, filtering processing, and end determination processing are performed in the above-mentioned order, and the above initialization processing, observation data versus track correspondence processing, or end determination processing is performed according to the command input by the operator from the console. It modifies the results of the process and also receives a message from the console, sends it to another console, and stores in the output buffer the position and velocity estimates of each target vehicle that is the output of the processor.

[0017]

[Action]

(1) For each track group candidate, filtering processing is performed using the observation data of all the sensors, and the estimated values of the position and speed of each target moving body are updated. The estimation accuracy of the truck can be improved. Further, in the observation data / trajectory correspondence processing, since the correlation processing for associating the observation data such as the azimuth by at least two sensors with the above-mentioned highly accurate track is performed, the accuracy of the 0-T correlation is increased, and the above problem (a) is caused. Can be solved.

(2) For each track set candidate, filtering processing is performed using the observation data of all sensors, and the estimated values of the position and speed of each target moving body are updated, so T-T
The above problem (b) can be solved by eliminating the need for correlation.

(3) Each sensor and each console are connected to a central processing unit, commands and messages input by the operator are output to the central processing unit and other consoles by the input unit, and the central processing unit is output by the output unit. Since the output of the above and messages from other consoles are displayed, each operator can judge by looking at the result of the processing device, enter commands from the console when necessary, and perform initialization processing, observation data vs. track correspondence processing, or The result of the end determination process can be modified. Further, since a message can be received and viewed from the consoles of other operators, a plurality of operators can cooperate with each other to make judgments, improve the accuracy of estimation, and solve the above problem (c).

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an overall configuration diagram of a first embodiment of a moving object tracking system according to the present invention.

The mobile tracking system (1) comprises at least two sensors (10), at least one console (20) and a central processing unit (30).

Each sensor (10) and each console (2
0) is connected to the central processing unit (30).

Each sensor (10) observes the orientation of at least one target moving body (40) and outputs the observation data to the central processing unit (30).

Each console (20) has an input device (21) such as a mouse and an output device (22) such as a display, and the operator (50) is operated by the input device (21).
Commands and messages entered by the central processing unit (3
0) or other console (20) and output device (2
By 2), the output of the central processing unit (30) and the message from the other console (20) are displayed.

The central processing unit (30) has an input buffer (31), a processing unit (32) and an output buffer (33), and the observation data from the sensor (10) is stored in the input buffer (31). .

The processing device (32) performs a moving body tracking process, which will be described later, and a predetermined process, which will be described later, according to a command input by the operator (50) from the console (20), and further, the console (20). Receives messages from other consoles (20)
Send to The output buffer (33) stores the estimated values of the position and speed of each target moving body (40) output from the processing device (32).

Next, the moving body tracking method according to the present invention will be described according to the contents of the moving body tracking processing by the processing device (32).

FIG. 2 is a flowchart showing the processing procedure of the moving body tracking method according to the present invention.

The outline of this method is initialization processing (100).
And observation data versus track correspondence processing (200), filtering processing (300), and end determination processing (400).

In the initialization processing (100), the observation data such as the direction of at least two sensors (10) for at least one target moving body (40) is input from the input buffer (31), and each sensor (10). By associating each of the observation data of 1) with one of the tracks of the target moving body (40), the observation data of each sensor (10) is composed of track data of the estimated number of target moving bodies at least one set of tracks. A pair of candidates is created, and an initial estimated value of the position and speed of each target moving body is calculated for each of the created candidates of each track group using the observation data associated with each other.

FIG. 3 is a diagram for explaining the initialization process (100). Taking a ship operation management support system as an example, the sensors S1 and S2 represent an azimuth sensor mounted on a buoy floating above the sea, and the target moving bodies T1 and T2 represent an unknown ship sailing in the vicinity thereof. The figure shows the two-dimensional positional relationship between the sensors S1 and S2 and the target moving bodies T1 and T2 in the initial state. The azimuth sensor S1 indicates the azimuth lines of the target moving bodies T1 and T2 by B11 and B, respectively.
12 is detected. Similarly, the sensor S2 has an azimuth line B2.
1 and B22 are detected. However, as shown in FIG. 4, the correspondence between the azimuth data by these two sensors is not limited to the correct track set 1 (T1, T2), but the incorrect track set 2 (T
1 ', T2') are possible candidates. Where T
1 ', T2' are bearing lines B11, B12 and B21, B2
It is another intersection of 2. As described above, when the estimated number of moving objects is N and the number of sensors is M, the number of candidates is the maximum (N
!! ) ** (M-1). When N or M becomes large, the number of combinations becomes enormous, and it takes a lot of processing time to search for the correct combination.

For each candidate, the initial position of the target moving body is obtained as the intersection of the azimuth lines. The initial velocity of the moving body can be obtained by similarly estimating the position after a fixed time. When the number of sensors is 3 or more, the least squares method may be applied.

Here, the number of candidates for the track group can be reduced by the following method.

For example, when the direction sensor has a detection distance limit, the initial position of each target moving body of each set of candidates is compared with the detection distance limit (3011, 3011 '), and if this initial position is the limit. If it is outside the range, the set can be excluded from the candidates.

In the observation data-to-track correspondence processing (200), the observation data such as the direction by the sensor (10) is input, and the correlation processing is performed in which the observation data of each sensor (10) is associated with the candidates of each track group. , Delete the candidates that do not correspond to the observation data.

The observation data / track correspondence processing will be described with reference to FIG.

It is assumed that, as a result of the following filtering process (300) at the previous time point, a set 1 and a set 2 are obtained as candidates for a set of trails. From the current observation data, the observation data sets A (C1, C2) and B (C1 ', C) are defined as the intersections of the azimuth lines B11, B12 and B21, B22.
2 ') is obtained. At this time, if the track set 1 corresponds to the observation data set A, but the track set 2 does not correspond to any observation data set, the track set 2 can be excluded as an impossible candidate. Here, for example, a chi-square test can be used to determine whether or not they correspond. That is, with respect to the observation matrix H determined by the filter model, the observation noise covariance matrix R, the state of the moving body that is the output of the filter, that is, the estimation error covariance matrix P of the position and velocity, and similarly the prediction residual dZ of the observation. , Chi-square amount = dZ'inv (HPH '+ R) dZ It is possible to judge by the magnitude of the amount given. Where'is the transpose,
inv indicates an inverse matrix.

In the filtering process (300), the candidate of each track group left without being deleted is subjected to the filtering process by using the observation data associated with the above correlation process, and the position of each target moving body (40). And the estimated value of velocity are updated and written in the output buffer (33).

Here, an ordinary extended (linearized) Kalman filter can be used for the file tally processing. That is, the unknown position and velocity of each target moving body (40) is the state quantity, the equation of motion is the dynamics model, and the equation expressing the observation data of the sensor (10) by the state quantity is the observation model according to the Kalman filter formula. It can be formulated.

In the end determination processing (400), the number of candidates of the above-mentioned track group is less than a predetermined number, and each target moving body (4
When the expected error between the position and velocity estimation values of 0) is less than or equal to a predetermined value, it is determined that tracking has ended.

Processing for Corresponding Observation Data to Track (200)
The filtering process (300) is repeated until it is determined that the tracking has ended.

Now, returning to the detailed description of the moving body tracking system in FIG.

The operator (50) is the console (20)
Through the mobile object tracking process.
That is, man-machine interactive processing can be performed.

From the console (20) to the operator (5
0) according to the command input, the result of the initialization process (100), the observation data versus track correspondence process (200), or the end determination process (400) is corrected during the moving body tracking process of the processing device (32). be able to.

The result of the initialization process (100) is sent from the output buffer (33) to the console (20) and is output to the output device (22) such as a display, for example, the geometrical relationship diagram of FIG. 3 and FIG. It is displayed in the form of a table. The operator (50) can judge by looking at this, exclude the impossible initial position, and exclude it from the candidates of the track set.

In addition, observation data vs. track correspondence processing (20
The result of 0) is similarly obtained, for example, in the geometrical relationship diagram of FIG.
And in the form of the table of FIG. Operator (5
0) makes a judgment by seeing this, eliminates the impossible correspondence of the observation data pair with the track group, and excludes it from the candidates of the track group.

Further, the result of the end judgment processing (400) is displayed in the form of a graph as shown in FIG. 6, for example. For each track group, the horizontal axis (6001) is the time, and the vertical axis (600
2) is taken as the estimation error covariance and the change is plotted (6
003) and the predetermined value (6004) is represented by a line. The operator (50) can judge by looking at this and terminate the tracking process.

Further, the operator (50) can input an arbitrary message from the console (20) and send it to the operator (50) of another console (20) via the central processing unit (30). As a result, a plurality of operators can consult with each other to make a decision in cooperation with each other, and the accuracy of tracking can be improved.

Further, it is possible to process with a smaller number of operators without arranging an operator for each of the plurality of sensors.

Next, a second embodiment of the moving body tracking system according to the present invention will be described.

FIG. 7 is a block diagram of the second embodiment of the moving body tracking system according to the present invention.

The difference from FIG. 1 is that each console (20) is provided with a central processing unit (30), and the central processing units (30) are connected to each other via a transmission line (60) to mutually exchange data. Are replaceable, and there are at least one sensor and at least two consoles.

In each central processing unit (30), the same processing as in the configuration of the first embodiment shown in FIG. 1 is performed, and the unknown position and speed of the target moving body (40) are estimated.

However, as shown below, the operator (50)
There is a difference in the interaction processing with.

Each operator (50) inputs a command from the console (20) in exactly the same manner as above, and the initialization processing (100) and observation data pair trace are performed during the moving body tracking processing in the processing device (32). The result of the handling process (200) or the end determination process (400) can be corrected.

Further, the operator (50) inputs an arbitrary message from the console (20), and the transmission line (6
0) to the operator (5) of another console (20)
0) can be sent.

In the second embodiment, differently from the first embodiment, each central processing unit (30) outputs the estimated value of the position and speed of each target moving body (40) as a processing result to the transmission line (60). )
To another central processing unit (30). This is a console (2) connected to another central processing unit (30).
0) is displayed on the output device (22).

FIG. 8 is a diagram showing the display area of the output device (22) in the second embodiment.

On the display (8001), in addition to its own display area (8002), an arbitrary number of display areas (8003) for data from other consoles are provided. As a result, the operator (50) can judge by referring to the information in the data display area (8003) from another console.

As a result, a plurality of operators can consult with each other to make a decision in cooperation with each other, and the tracking accuracy can be improved.

Further, according to this system configuration, the processing can be continued even if a part of the plurality of central processing units (30) goes down, and the availability of the system is enhanced.

[0063]

The present invention has the following effects.

(1) Even in the case of a passive sensor, it is possible to realize a moving body tracking system which uses a plurality of sensors to accurately estimate unknown positions, velocities, etc. of a plurality of target moving bodies from the observation data. .

(2) A plurality of operators can cooperate with each other to make judgments and improve the accuracy of estimation.

(3) An operator is not provided for each of the plurality of sensors, and processing can be performed by a smaller number of operators. (4) Processing can be continued even if some of the plurality of central processing units go down.

[Brief description of drawings]

FIG. 1 is an overall configuration diagram of a mobile body tracking system according to the present invention.

FIG. 2 is a flowchart showing a processing procedure of a moving body tracking method according to the present invention.

FIG. 3 is a diagram for explaining initialization processing.

FIG. 4 is a diagram for explaining candidates for a set of wakes.

FIG. 5 is a diagram for explaining processing of observation data versus track correspondence.

FIG. 6 is a diagram for explaining end determination processing.

FIG. 7 is another configuration diagram of the mobile tracking system according to the present invention.

FIG. 8 is a diagram showing a display area of an output device (22) in the second embodiment.

[Explanation of symbols]

1 ... Moving object tracking system, 10 ... Sensor, 20
... console, 30 ... central processing unit, 40 ... target moving body, 50 ... operator, 60 ... transmission path, 100 ... initialization processing, 200 ... observation data vs. track correspondence processing, 300 ... filtering processing, 400 ... end determination processing.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Hiro Takahashi 216 Totsuka-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Ltd.Hitachi, Ltd., Information & Communication Division (72) Inventor, Shoji Tada Totsuka, Totsuka-ku, Yokohama, Kanagawa 216, Machi Incorporated company Hitachi Ltd. Information & Communication Division

Claims (4)

[Claims] 1. Initialization processing (100), observation data / track correspondence processing (200), and filtering processing (30)
0) and an end determination process (400), wherein the initialization process (100) includes an orientation of at least two target sensors (40) for at least one target mobile object (40). The observation data of each sensor (10) is associated with one of the tracks which is the estimated value of the target moving body (40), and the observation data of each sensor (10) is moved to the target movement. At least one track set candidate consisting of track data of the estimated number of bodies is created, and for each created track set candidate, the target moving body (40) of each target moving body (40) is used by using the above-mentioned associated observation data. This is a process of calculating initial estimated values of position and velocity. In the observation data / track correspondence process (200), the observation data such as the bearing by the sensor (10) is input, and each sensor (10) This is a process of correlating the observation data with the candidates of each track set, and deleting the candidates that do not correspond to the observation data. The filtering process (300) is a candidate of each track set that remains undeleted. Is a process of performing a filtering process using the observation data associated with the correlation process to update the estimated value of the position and velocity of each target moving body (40), and the end determination process (400) is When the number of remaining track set candidates is less than or equal to a predetermined number and the expected error of the estimated value of the position and speed of each target moving body (40) is less than or equal to a predetermined value, it is determined that tracking has ended, and the above observation data is obtained. A moving body tracking method, which is a process of repeating the anti-trajectory handling process (200) and the filtering process (300) until it is determined that tracking has ended. 2. The initialization processing (100) comprises, for each track set candidate, a detection distance limit (30) for which the initial position of each target moving body (40) is a sensor (10).
The moving object tracking method according to claim 1, wherein the processing is to remove the set from the candidates if it is outside 11). 3. Two or more sensors (10), at least one console (20) and a central processing unit (30).
A mobile tracking system comprising: a sensor (10) and a console (20) connected to a central processing unit (30), each sensor (10) including at least one target. The observation data is output to the central processing unit (30) by observing the orientation of the moving body (40), and each console (20) is provided with an input device (21) such as a mouse and an output device (such as a display). 22), the input device (21) sends commands and messages input by the operator (50) to the central processing unit (30) and other consoles (20), and the output device (22). Is for outputting the output of the central processing unit (30) and the message from the other console (20). The central processing unit (30) includes an input buffer (31) and a processing unit (3). ) And an output buffer (33), the input buffer (31) stores the observation data from the sensor (10), and the processing device (32) includes an initialization process (100) and an observation data pair. Track response processing (2
00), filtering processing (300), and end determination processing (400), and initialization processing (100) determines the orientation of at least one target moving body (40) by at least two sensors (10). The observation data is input from the input buffer (31), the observation data of each sensor (10) is associated with one of the tracks of the target moving body (40), and the observation data of each sensor (10) is moved to the target. The position of each target moving body (40) is created using at least one track set candidate composed of the tracks of the estimated number of bodies, and using the associated observation data for each created track set candidate. Is a process of calculating an initial estimated value of the velocity, and the observation data-to-track correspondence process (200) inputs the observation data such as the bearing by the sensor (10) and This is a process of correlating the observation data of 10) with the candidates of each track set, and deleting the candidates that do not correspond to the observation data. The filtering process (300) is the process of deleting each track that has not been deleted. With respect to the candidates of the set, filtering processing is performed using the observation data associated with the correlation processing, the estimated values of the position and velocity of each target moving body (40) are updated, and the processing is written in the output buffer (33). In the end determination process (400), the number of remaining track set candidates is less than or equal to a predetermined number, and the expected error of the estimated value of the position and speed of each target moving body (40) is less than or equal to a predetermined value. If it is determined that tracking has ended, the observation data-to-track correspondence processing (200) and filtering processing (300) are repeated until it is determined that tracking has ended, and the console ( According to the command input by the operator (50) from 20), the result of the initialization process (100), the observation data-track correspondence process (200), or the end determination process (400) is corrected, and the console (20) Received a message from
The message is sent to another console (20), and the output buffer (33) stores the estimated values of the position and velocity of each target moving body (40) which is the output of the processing device (32). Mobile tracking system. 4. A mobile tracking system having at least one sensor (10), at least two consoles (20), and as many central processing units (30) as there are consoles (20). Each sensor (10) is connected to each central processing unit (30), each console (20) is connected to one central processing unit (30), and each central processing unit (30) is connected. Are connected to each other via a transmission line (60) and data can be exchanged. Each sensor (10) observes the orientation of at least one target moving body (40) and the observed data Each console (20) has an input device (21) such as a mouse and an output device (22) such as a display, and the input device (21) is an operator ( 0) outputs the input command and message to the central processing unit (30) and other consoles (20), and the output device (22) outputs the central processing unit (30) and messages from other consoles (20). Each central processing unit (30) has an input buffer (31), a processing unit (32) and an output buffer (33), and the input buffer (31) is connected to the sensor (10). The processing device (32) stores observation data, and the processing device (32) performs initialization processing (100) and observation data vs. track correspondence processing (2).
00), filtering processing (300), and end determination processing (400), and initialization processing (100) determines the orientation of at least one target moving body (40) by at least one sensor (10). By inputting the observation data from the input buffer (31) and associating the observation data of each sensor (10) with one of the tracks of the target moving body (40), the observation data of each sensor (10) becomes the target. At least one track set candidate composed of track data of the estimated number of moving bodies is created, and the target moving body (40) of each target moving body (40) is created using the observation data associated with each created track set candidate. This is a process of calculating initial estimated values of position and velocity. The observation data-to-track correspondence process (200) is the process of observing the direction data of the sensor (10). Is input, correlation processing is performed to correlate the observation data of each sensor (10) with each track set candidate, and the candidate that does not correspond to the observation data is deleted. The filtering processing (300) is With respect to each of the remaining track set candidates that have not been retained, filtering processing is performed using the observation data associated with the correlation processing, and the estimated values of the position and velocity of each target moving body (40) are updated to output buffer. In the end determination process (400), the number of remaining track group candidates is equal to or less than a predetermined number, and the estimated value of the position and velocity of each target moving body (40) is expected. When the error is equal to or less than the predetermined value, it is determined that the tracking has ended, and the observation data-to-track correspondence processing (200) and the filtering processing (300) are repeated until it is determined that the tracking has ended. Then, according to the command input by the operator (50) from the console (20), the result of the initialization process (100), the observation data versus track correspondence process (200), or the end determination process (400) is corrected, and the console ( 20) receives a message from the other console (20) via the transmission line (60).
To the other central processing unit (30) via the transmission path (60), and the output buffer (33) outputs the estimated values of the position and speed of each target moving body (40) to the central processing unit (30). A moving body tracking system for storing the estimated values of the position and speed of each target moving body (40), which is the output of the processing device (32).