JPH04177410A - Automatic tracking device for mobile object - Google Patents

Abstract

PURPOSE:To detect an accurate direction of an optical axis of an image pickup device and to automatically track a mobile object by providing a turning angle acceleration sensor and an elevation angle acceleration sensor at the places near the turning axis of the image pickup device. CONSTITUTION:An image pickup device 1 using an ITV camera, etc., is set on a drive stage 2 in a controllable way for turning and the angle of elevation. An image processor 5 inputs the image signal 3 outputted from the device 1 and outputs a geometric centroid 9 of a mobile object. The centroid 9 is processed by a position arithmetic unit 6 and a measurement value output signal. 8 is outputted. A drive stage controller 7 outputs a drive stage control signal 4 in order to catch the mobile object at the center position of an image of the device 1 based on the coordinates of the centroid 9. The angle acceleration sensor units 38-1-and 38-2 are attached at the places near a turning axis and an elevation angle axis of the device 1 respectively. A direction changed variable computing element 40 generates the image pickup direction of the device 1 and outputs it to the processor 5.

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention captures an image of a moving object with the imaging device of the TV right camera, determines the position of the moving object through image processing, and repeats this process, thereby continuously moving the object. The present invention relates to an automatic tracking device for a moving object that tracks an object.

[Prior Art] This invention is based on the patent application No. 61-2119 previously filed by the applicant.
No. 20 and Japanese Patent Application No. 63-277162. In these applications, the elevation angle, rotation angle, etc. that constitute the imaging direction of the imaging device, which is a parameter for tracking a moving object, are determined by a pulse generator, the rotation axis of the drive base, the displacement of the elevation axis, etc.
A method of directly detecting the angle of a rotating axis relative to a fixed axis, such as an absolute encoder or synchro transmitter, was used.

[Problems to be solved by the invention] For this reason, if the rigidity of the drive base around the rotation axis is low, a misalignment will occur between the detection direction and the camera optical axis direction, and accurate detection may not be possible. . Further, when the driving platform is installed and operated on a mobile cart or the like, the camera optical axis direction cannot be detected in principle using the above-mentioned detection method. Therefore, in this invention, we have solved these problems and can accurately capture images even when the rigidity of the drive base around the rotation axis is not high enough or when the drive base is used on a moving body such as a mobile trolley. An object of the present invention is to provide an automatic tracking device for a moving object that can detect the optical axis direction of the device.

[Means for Solving the Problems] According to the automatic tracking device for a moving object according to the present invention, there is provided an imaging device that images a moving object and outputs a video signal, and an imaging device that processes the imaging signal from the imaging device to output the video signal. A moving object comprising: a control device that generates a control signal to control automatic tracking of the moving object; and a drive base that supports the imaging device and controls the imaging direction of the imaging device based on the control signal from the control device. In this automatic tracking device, a turning angular acceleration sensor for detecting turning angular acceleration is provided near the turning axis of the imaging device, and an elevation angle acceleration sensor for detecting elevation angular acceleration is provided near the elevation axis of the imaging device, and the turning angular acceleration and an elevation angle acceleration and an imaging signal, and in synchronization with the imaging signal, integrate the turning angular acceleration and elevation angle acceleration to generate an elevation azimuth displacement amount and a turning azimuth displacement amount, and output them to the control device. The feature is that a quantity calculator is provided.

[Example] The present invention will be described below based on illustrated embodiments.

FIG. 1 shows a side view of the configuration of an embodiment of the present invention.

In the configuration shown in FIG. 1, an imaging device 1 in which an ITV camera or the like is used, a drive stand 2 that supports the imaging device 1 in a manner that allows rotation and elevation control, and an image signal 3 output from the imaging device 1 are input. An image processing device 5 that processes and outputs a geometric center of gravity 9 of a moving object; a position calculation device 6 that processes this geometric center of gravity 9 and outputs a measurement value output signal 8; and a geometric center of gravity from this position calculation device 6. A driving table control device 7 that outputs a driving table control signal 4 to a driving table 2 so as to capture a moving object at the center of an image of an imaging device based on coordinates is disclosed in Japanese Patent Application No. 61-211920 previously disclosed by the applicant. , has the same structure as that of Japanese Patent Application No. 63-277162, and detailed explanation thereof will be omitted. Furthermore, in the configuration of the present invention, angular acceleration sensor units 38-1 and 38-2 are attached near the rotation axis and the elevation axis of the imaging device 1, respectively.

In addition, these angular acceleration sensor units 38-1.38
-2 output 39-1.39-2 and the image signal 3 are input to generate the imaging orientation 10 of the imaging device 1, and an orientation change amount calculation unit 40 is newly provided which outputs the imaging orientation to the image processing device. It is being

FIG. 2 shows a detailed configuration diagram of the turning angle angular acceleration sensor unit 38-1 installed near the turning axis.
In this angular acceleration sensor unit 38-1, a set of acceleration sensors 41A141B are arranged so as to be symmetrical with each other at a distance of 1 with respect to the rotation axis. Therefore, each set of acceleration sensor signals aAsaB is output to the azimuth change amount calculator 40 as the detection output of the angular acceleration sensor unit 38-1. The angular acceleration sensor unit 38-2 for measuring elevation and elevation, which is installed near the elevation center axis, has a similar configuration, and from a set of acceleration sensors 41.41B,
Similarly, acceleration sensor A No. a4. Since aBi is output, illustration thereof is omitted.

Next, the configuration of the azimuth change amount calculator 40 will be explained based on FIG. As is clear from the illustrated block configuration, this azimuth change amount calculator 40 uses the detection signal aASaB of the angular acceleration sensor unit 38-1 around the turning center axis.
is input, and the upper half system in the block that finally outputs the amount of turning azimuth displacement Δθ is input, and the detection signals a^ and aB of the angular acceleration sensor unit 38-2 around the elevation center axis are input, and the final result is and a lower half system that generates the turning azimuth transition amount Δθ, but since the configurations of both are the same, the configuration and operation of the block that outputs the turning azimuth transition amount Δθ will be explained. Strain gauge amplifiers 47 and 48 are provided at the input stage of this azimuth change amount calculator 40, and the detection signal aASaB of the angular acceleration sensor unit 38-1 is inputted through the line 39-1 and processed for signal processing. Amplify to appropriate value and output “aA”, “aB”
is input to the acceleration/angle converter 45 via lines 43 and 44.

This acceleration/angle converter 45 inputs the point-symmetric distance parameter regarding the turning center axis, and performs the calculation of
It is configured to exclude accelerations such as gravity other than the rotational angular velocity around the central axis of rotation and extract only the rotational angular velocity around the axis.

The angular velocity θ generated by this acceleration/angle converter 45 is integrated by integrators 49 and 50 connected in series in two stages to generate θ. An integrator 49 connected in series with these two stages
．． An analog latch circuit 46 that receives the image signal 3 is provided at the output end of the image signal 3, and after latching the output θ for the horizontal synchronization period of the horizontal synchronization signal extracted from the image signal 3, the turning azimuth displacement amount Δθ Output. This analog latch circuit 46 performs the above-mentioned two operations together with this latch operation.
A reset signal is sent to each of the integrators 49 and 50 connected in series in the stage to perform reset for θ integration when scanning the object to be tracked in the next imaging frame.

Similarly to the above, in the lower half block of the acceleration/angular velocity converter 45 in the figure, the detection signal ai of the angular acceleration sensor unit 38-2 around the central axis of elevation is input, and the elevation/elevation direction is finally changed. A quantity Δθ is generated.

As described above, when the driving base rotates and rises in order to capture a moving object to be tracked at the center of the imaging screen by the imaging device 1, the acceleration sensor 41 of the angular acceleration sensor unit 38-1.2.
41B detects acceleration and outputs acceleration signals aA' aB Sa 1 and BE.

The strain amplifier 47.48 in the direction change amount calculator 40
．． Acceleration signal a to an appropriate voltage value by 47', 48-
AN aB s aA% After aB is amplified, the acceleration/angular velocity converter 45 converts the acceleration into angular velocity. The angular velocity θ obtained in this way is converted from θ to θ and further to θ by a two-stage integrator 49.50 which is reset by a reset signal, and is latched by an analog latch circuit 46 for a horizontal synchronization period, after which the turning azimuth displacement amount Δθ and , the elevational direction transition amount Δθ.

is generated.

In this way, integrating and extracting θ from the angular velocity d is repeated for each image scan synchronized with the horizontal synchronization signal in the imaging bag a1, and the azimuth change amount 10 (turning azimuth displacement amount Δ
θ and the elevation/direction transition amount Δθ) are continuously determined. The amount of azimuth change 10 obtained in this way is transferred to the image processing device 5.
The geometric center of gravity 9 can be determined accurately by supplying

Since the gist of this invention is to generate the imaging orientation 10, the configurations of the image processing device 5 and the position calculation device 6 will not be described in detail. No. 63-2771
It goes without saying that configurations such as No. 62 can be used. Although not mentioned in this embodiment, if the angular velocity θ, which is the output of the acceleration/angular velocity converter 45, is configured to be output to the drive base control device 7, the angular velocity of the drive base 2 can be controlled with higher precision. This makes it possible to improve the control performance of the drive base 2 against acceleration disturbances, obtain a stable image signal with less blurring, and improve the automatic tracking performance of the entire system.

[Effects of the Invention] The embodiments of the automatic tracking device for moving objects according to the present invention are as described above, and the following effects can be achieved.

Even when the rigidity of the drive base that supports the imaging device is low, or when the imaging device is installed on a moving body, the amount of change in the imaging orientation can be calculated accurately.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, FIG. 2 is an enlarged view showing the configuration of the angular velocity sensor unit, and FIG.
The figure is a detailed block diagram of the azimuth change amount calculator. DESCRIPTION OF SYMBOLS 1... Imaging device, 2... Drive stand, 3... Image signal, 4... Drive stand control signal, 5... Image processing device, 6
...Position calculation device, 7...Drive platform control device, 8...
・Measurement value output signal, 9...Geometric center of gravity, 10...Imaging direction, 38-1.38-2...Angular velocity sensor unit, 39...Acceleration sensor signal, 40...Amount of change in direction Arithmetic unit, 41.41B... Acceleration sensor, 43.4
4... Acceleration sensor amplified signal, 45... Acceleration/angular velocity converter, 46... Analog latch circuit, 47.4
8... Strain gauge amplifier, 49.50... Integrator.

Claims (2)

[Claims] (1) An imaging device that images a moving object and outputs a video signal, a control device that processes the imaging signal from the imaging device and generates a control signal to control automatic tracking of the moving object, and the imaging device an automatic tracking device for a moving object, comprising: a drive base that supports a drive base and controls the imaging direction of the imaging device based on a control signal from the control device; a turning angular acceleration sensor that detects the turning angular acceleration of the imaging device; an elevation angle acceleration sensor that is provided near the elevation axis of the imaging device and detects the elevation angular acceleration of the imaging device; and the turning angular acceleration and the elevation angular acceleration and imaging. an azimuth change amount calculator that receives a signal and integrates the turning angular acceleration and the elevation angle acceleration in synchronization with the imaging signal to generate an elevation azimuth displacement amount and a turning azimuth displacement amount and outputs the same to the control device. An automatic tracking device for moving objects characterized by: (2) In the first aspect, the turning angle acceleration sensor and the elevation angle acceleration sensor are arranged point-symmetrically with respect to the turning center axis and the elevation center axis of the imaging device, respectively, and each outputs two acceleration signals. The azimuth change calculation unit processes two acceleration signals output from each set of acceleration sensors to calculate the rotational angular velocity around the rotation center axis and the elevation center axis. an acceleration/angular velocity converter for extracting the rotational angular velocity, two integrators connected in series for integrating the rotational angular velocity, and a horizontal synchronization period of the horizontal synchronization signal extracted from the imaging signal to which the output of the integrator is inputted to the integrator. An analog latch circuit that latches an output and outputs a turning displacement amount and an elevation displacement amount, and outputs a reset signal to the two integrators in synchronization with the horizontal synchronization period. Automatic object tracking device.