JPH0474905A - Detecting mechanism for position of camera - Google Patents

Abstract

PURPOSE:To detect the degree of inclination of a camera based on the comparison of the central positions of cross sections which differ depending on the height of a target by obtaining photographed images of the target by the camera before a production line is driven. CONSTITUTION:In the first place, when the production line is driven, an image of a target 4 is input from a camera 1. When the target is seen, from right above, a lower end part 4a, an intermediate part 4b and an upper end part 4c of a cone 4 is photographed, resulting in the image formed of black, white and black concentric circles from outside of a monitor TV6. If the coordinates of the center 01 of the outer black circle are agreed with the coordinates of the center 02 of the inner black circle, the camera 1 is not inclined and fixed at the regular position. However, if the coordinates are not agreed, the camera 1 is inclined. The direction and amount of the inclination of the camera 1 can be obtained from the vector from the center 01 to the center 02.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a camera position detection mechanism for inspecting the inclination of a camera that is fixedly installed on a production line and captures an image of an object to be imaged, for example. It is.

[Conventional technology]

On a production line where images from cameras are processed manually, there may be problems with the attached camera or some other cause (collision,
It may be tilted due to vibration, etc.). In that case, the distance from the lens to the object will not be constant depending on the position of the object, so the pre-measured scaling data (actual data for the -image) will be different from the original value and will be invalid. , errors occur in the data processed by manually generated images.

(Problem to be solved by the invention) For this reason, it is necessary to correct the inclination of the camera fixedly installed on the production line, but conventionally, the means to know the direction of the inclination of the camera has been limited to visual confirmation. There was a problem with the warm taste and the fact that it took time to correct the tilt of the camera.

The present invention has been made in view of the above points, and an object of the present invention is to provide a camera position detection mechanism that can quantitatively detect the degree of inclination of the camera.

(Means for Solving the Problems) A camera position detection mechanism according to the present invention is installed on a vertical line of a mounting surface on which an object to be imaged is placed, and detects the degree of inclination of the camera that captures an image of the object to be imaged. For detection, a cone whose cross-sectional area uniformly changes sequentially from the bottom surface in the height direction is used as a target, and an image of the target is obtained by the camera and the height position of the target is determined. The degree of inclination of the camera is detected based on the comparison of the center positions of different cross sections.

[Effect]

The camera position detection mechanism of the present invention uses a cone as a target and obtains an image of the target with a camera before the production line starts operating, and is based on the comparison of the center position of a cross section that varies depending on the height position of the target. The tilt angle of the camera is detected.

〔Example〕

An embodiment of the present invention will be described below with reference to the drawings. 1st
The figure is a schematic explanatory diagram of the camera position detection mechanism according to this embodiment. In the figure, (1) is installed on the production line and the mounting surface (
3) A camera that captures an image of the target (4) above through the lens (2), (5) indicates illumination that illuminates the target (4), and the target (4) is placed on a horizontal mounting surface (3). ) is used to check the inclination of the imaging surface of the camera (1), which is on the vertical line of The part (4b) is white, the upper part (4c) up to the apex is white.
) are black. It is assumed that there is no dirt on the target (4) and lens (2), and no deterioration of the illumination (5).

By using the target (4) as described above, the degree of inclination of the camera (1) can be detected. That is, for example, at the beginning of operation on a production line, the camera (1) inputs an image of the target (4), and when this target is viewed from directly above, the image of the camera (1) looks like the one shown in Figure 2. , the lower end (4a), middle part (4b), and upper end (4c) of the cone (4), which are concentric circles of black, white, and black from the outside, are imaged on the monitor TV (6).

Here, the center of the outer black part is 0. The coordinates of (the center of the circumscribed rectangle) and the coordinates of the center 02 of the inner black part are the second
As shown in the figure, if they match, the camera (1) is fixedly installed in the correct position without tilting, and
If they do not match as shown in Figure 3, camera (1)
It can be determined that the is tilted. In addition, in Figure 3, from the vector from center 0 to center 02, the camera (
1) The direction of inclination and the amount of inclination can be determined.

FIG. 4 shows a control calculation section of the position detection mechanism of the camera, and this control calculation section (10) is composed of a CPU (10a) RO
M (10b) is equipped with a RAM (10c) and an interface (10d) (in addition, (11) is a power supply for illumination), and as shown in FIGS. 2 and 3 above, the imaging screen of the target (4) is It is determined whether the camera (1) is tilted based on the input coordinate values 01°02, and if it is not tilted, for example, an OK light (not shown) is displayed and controlled,
If it is tilted, it is possible to drive and control an alarm device (not shown), for example. Also, the above coordinate value 0. ,0. The direction and amount of inclination can be determined from the vector based on the vector, and the degree of inclination of the camera (1) can be corrected accordingly.

In the above embodiment, the target (4) has a conical shape, but it may also be a pyramid, a truncated cone, a truncated truncated pyramid, etc., and its cross section is uniformly shaped from the bottom surface in the height direction. It may be a cone whose area changes sequentially, and the surface color, pattern, etc. may be changed so that the center position can be determined depending on the height position.

[Effects of the Invention] As described above, according to the present invention, with a female body as a target, before the production line starts operating, a captured image of the target is obtained by a camera, and the center position of the cross section that differs depending on the height position of the target is determined. Since the degree of inclination of the camera is detected based on the comparison, there is an effect that the degree of inclination of the camera can be quantitatively detected.

[Brief explanation of drawings]

Fig. 1 is a schematic explanatory diagram showing a camera position detection mechanism according to an embodiment of the present invention, Fig. 2 is an explanatory diagram of an input image of a target when the camera is not tilted, and Fig. 343 is an explanatory diagram when the camera is tilted. Explanatory diagram of the input image of the target, 4th
The figure is a simple block diagram of the control calculation section of the present invention. In the figure, (1) is a camera, (3) is a mounting surface, (4) is a target, and (lO) is a control calculation unit. In each figure, the same reference numerals indicate the same or corresponding parts: , 8-
11th diagram diagram

Claims (1)

[Claims] In order to detect the inclination of a camera that is installed on a vertical line of the mounting surface on which the object to be imaged is placed and captures the image of the object to be imaged, the cross-sectional area is uniformly measured from the bottom surface along the height direction. A camera comprising a sequentially changing cone as a target, and detecting the degree of inclination of the camera based on a comparison of center positions of different sections depending on the height position of the target by obtaining a captured image of the target by the camera. Position detection mechanism.