JPH032981A - Sign recognizing device - Google Patents

Abstract

PURPOSE:To always catch a sign at a prescribed position despite some change of the attitude, etc., of a mobile object and to accurately detect the sign by detecting the reflected light of the light projected to a reflector and controlling an image pickup means so as to catch the sign at a prescribed position of a screen in response to the position of the detected reflected light. CONSTITUTION:An image pickup means 11 to be used to photograph a sign 3, a light emitting source 9 which projects the light to a reflector 5 are provided. A detection means 21 which detects the light projected from the source 9 and reflected by the reflector 5, a control means 23 which controls the image pickup position of the means 11 so that the means 11 catches the sign 3 at a prescribed position in response to the position of the reflected light 5 which is detected by the means 21 are provided. Thus the sign 3 is always caught in a prescribed area like the center, etc., of a screen and therefore can be accurately detected.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a sign recognition device that detects signs such as road signs that are present in the direction of movement of a moving object such as a vehicle.

(Prior art) Conventional sign recognition devices include, for example, the ``Development of Road Sign Recognition Systems J
(I: Ippon Raiso Co., Ltd., p. 28) This road sign recognition system uses a camera mounted on the vehicle to detect road signs that appear on the screen as the vehicle moves forward. Focus on moving from the left to the top, limit the left and top edges of the screen as the scanning area for the sign, and scan only this limited specific scanning area to detect the sign. ing.

(Problems to be Solved by the Invention) In the conventional road sign recognition system described above, the scanning area is limited and fixed so that only a specific area on the screen is scanned to recognize the sign. When the attitude of the vehicle changes or the vehicle speed changes, for example, to a high speed, there is a problem in that the sign does not fit into a specific area on the screen, making it impossible to accurately detect the sign.

The present invention has been made in view of the above, and its purpose is a sign recognition device capable of accurately detecting a sign by controlling the sign to always be captured in a predetermined area such as the center of the screen. The goal is to provide the following.

[Structure of the Invention] (Means for Solving the Problems) In order to achieve the above object, the sign identification device of the present invention uses a sign that is mounted on a moving body and has a reflecting mirror that is present in the moving direction of the moving body. A sign recognition device for detecting, comprising: an imaging means for forming an image of the sign; a light emitting source that emits light toward a +Vi reflecting mirror; and light reflected from the reflecting mirror of the light emitted from the light emitting source. and a detection means for detecting 1frj according to the position of the reflected light detected by the detection means.
l；[! The gist of the present invention is to include a control means for controlling the imaging position of the imaging means so as to capture the sign at a predetermined position.

(Function) In the sign recognition device of the present invention, the reflected light of the light emitted toward the anti-rJ4 mirror is detected, and the imaging means is configured to capture the sign at a predetermined position on the screen according to the position of the detected reflected light. It's in control.

(Example) The following is a detailed explanation of the present invention using the drawings.

FIG. 1 is a block diagram showing a sign recognition device 13 according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the sign recognition device 13 in FIG. ＞The same components are given the same code (=1).

As shown in FIGS. 1 and 2, this 4M recognition device is mounted on a vehicle 1, which is a moving object, and detects a J0 road sign 3 erected on the ground in front of the vehicle 1 in the direction of movement. It looks like this. Note that a reflecting mirror 5 made of a corner cube or the like is attached to the road sign 3.

The sign recognition device 17 mounted on the vehicle 1 has a movable pedestal mechanism 7 consisting of a tilt angle adjustment mechanism 78 and a pan angle adjustment mechanism 7b. A light emitting source 9 is integrally housed, and an image carrying device 611 is further attached above the light emitting source 9. A zoom up lens 13 is attached to the front of the image carrying device 11. The zoom mechanism of the zoom up lens 13 is controlled by the aicTi 27.

Further, a lens 15 and a half mirror 17 are attached to the front side of the light source 9, and the light from the light source 9 illuminates the road sign 3 and the reflecting mirror 5 in front of the vehicle 1 via the lens 15 and the half mirror 17. It is supposed to be done.

As described above, the reflecting mirror 5 is formed of, for example, a mesh of corner cues 1, and the corner cubes have the property of returning reflected light in the direction of incidence of the light. Therefore, the light reflected from the reflecting mirror 5 from the light emitting source 9 via the lens 15 and the half mirror 17 is reflected toward the light emitting source 9, and is reflected from the half mirror provided on the front side of the light emitting source 9. -17, and passes through the imaging lens 19 as PSD (Pos
The detected reflected light signal is detected by an analog two-dimensional area sensor 21 called an actuator controller 2.
3. The actuator controller 23 detects the difference detected by the area sensor 21! 8 The tilt angle adjustment mechanism 7 of the movable pedestal mechanism 7 uses the control signal attached to the optical signal.
a and the pan angle adjustment mechanism 7b, so that the reflected light image from the reflecting mirror 5 is always located at a predetermined position on the area sensor 21'2, 1, at the center position above the area sensor 21', 1', and the pan angle adjusting mechanism 7b. aill 6OL. Note that the half mirror 17, the imaging lens 19, and the area sensor 21
is mounted on the movable base machine 17 and operates in conjunction with the image device 11 and the light emitting source 9.

A tilt angle sensor 25 is provided in each of the tilt angle adjustment R mechanism 78 and the pan angle adjustment mechanism 7b that constitute the movable pedestal mechanism 7.
A and the pan angle sensor 25b are removed, so that the direction of the light emitted from the light emitting source 9 and the direction of the road sign 3 and the reflector 5 from the vehicle 1 can be determined. . The peak angle signals detected by the tilt angle sensor 25a and the pan angle sensor 25b are supplied to a driver 27, and the zoom up lens 13 is controlled via the driver 27. Further, a speed sensor 29 is attached to the vehicle 1 to detect the speed of the vehicle 1, and the detected speed signal is supplied to the calculator 27.

In the device constructed as described above, while the vehicle 1 is running, the light emitted from the light emitting source 9 mounted on the vehicle 1 is transmitted through the lens 15 and the half mirror 17 at a certain angle to the front of the vehicle 1. When it reaches the road sign 3 and the reflecting mirror 5, it is reflected by the anti-rA mirror 5, returned to the light emitting source 9, and reflected by the half mirror 17 provided on the front side of the light emitting source 9. An image is formed on the area sensor 21-1- via the lens 19.

FIG. 3 shows how the light thus reflected by the reflecting mirror 5 is further reflected by the half mirror 17 and forms an image 4 on the area sensor 21 via the imaging lens 19. The imaging position P of the reflected light on the area sensor 21 in case 1 shown in FIG. 3 is detected as two-dimensional coordinate information P (x, y), and is supplied to the actuator υ controller 23.

The actuator control device 23 determines the coordinates of this foul light on the area sensor 21? The I-information ρ(X, V) is set at a predetermined coordinate position, that is, the coordinate position P (xc
l, yd), both coordinates; IX: 4A arch ε
X, εy (εX = X−xd, 6y −y−yd
) (No. 5 is a tilt angle adjustment mechanism 7aJyJ
, to the movable pedestal mechanism 7 consisting of the pan angle adjustment mechanism 7b, so that the tilt angle adjustment a horizontal 78 and pan angle Controls the adjustment mechanism 7b. Rinawachi,
The tilt angle adjustment mechanism 78 and the pan angle adjustment mechanism 7b are controlled by the tilt angle adjustment mechanism 7a and the pan angle adjustment mechanism 7b, and the light emitting source 943 attached to the movable base mechanism 7 and the image. The direction of the device 11 is controlled, thereby controlling the direction of the light from the light emitting source 9 and the direction of the path image of the image carrier 11, so that the reflected light from the reflecting mirror 5 is directed to a predetermined position on the rear lens 21. The image is controlled so that it is always located at the center 11/1, and the image of the image carrier 11 is controlled so that it is always located at the center of the screen. As a result, the road sign 3 can be detected accurately at all times.

Further, the image of the road sign 3 formed by the image device 11 will be captured on the screen small or large depending on the distance from the vehicle 1 to the road sign 3, but in this way, the image of the road sign 3 is small or If it's big,
Although it may be difficult to detect road signs 3, the sign recognition device shown in FIG. I'm in control. This is done by measuring the distance from the image 5A camera 11 mounted on the vehicle 1 to the road sign 3, and adjusting the zoom up lens 13 attached to the image device 11 according to this distance.

Specifically, as shown in FIG. 4, when the vehicle 1 is operating at a speed V, the angle of the rear reflector 5 of the vehicle 1 with respect to the traveling direction of the vehicle 1 is at time t-8t. Set it to 01. Note that this angle is obtained from the pan angle adjustment mechanism 7b of the movable pedestal mechanism 7. Further, Δ[ is the control period of the present sign recognition device.

Reflector 5, which was at J5 and at angle θ1 at time (-△[,
11 of the next control cycle of device 6. ++ In the 4th
The distance # shown in the figure is long (that is, medium and both speeds 1ηV
&Q Suppose that the angle of 5'' is θ2, and in this case, if the linear distance between the anti-Q=1 mirror ?5- and the l!i1 image device 1 in Fig. 4 is 0, then Place 11 on the image at this time.
The device l- from to the reflector 5' is (Ai. + 琵> tan θ1 - Ai Q tan θ21 - = Ai 0/cos θ2 by eliminating Ai 0 from 1 = U tan f), /cos θ2
(tan θ2 −tan 01 )=VΔt−
tan θt/cos θ2 (tan 02 - tan θ I).

Therefore, the speed 1α sensor 29 shown in FIG.
, and further measure the orientation 0 of the imaging device 11 with respect to the reflecting mirror 5 as described above, and input these measurements (16 into the operator 27 to calculate the above equation. By determining the distance ML, and adjusting the zoom-up n) of the zoom-up lens 13 according to this distance 1-, the size of the image of the road sign 3 imaged by the dancing image neck 11 is always kept constant. This allows the road sign 3 to be accurately identified. Incidentally, FIG. 5 is a flow diagram showing the above-mentioned operation.

” By using the sign identification by the two consecutive sign recognition devices, for example, when a no entry sign is detected, it is possible to issue a warning to the driver of the vehicle 1. In the case of an unmanned autonomous vehicle, this sign identification result is used as b, for example, if a stop sign is detected, the vehicle is stopped with a predetermined program, or a no entry sign is detected. If this is detected, the vehicle can be controlled such as making a detour.

Note that the label recognition device of the present invention can be used, for example, when the above-mentioned h"δ1g
l! Configuring an associative memory circuit using a small device RAM in the device 4
It can be used to recognize a specific object that has been stored in advance.

Further, FIG. 6 shows a vehicle 1 equipped with the present traffic sign recognition device about to turn right at an intersection, but in this case, since the vehicle 1 is stopped in the intersection, an oncoming vehicle 5 If a vehicle approaches the Sokame v''c intersection, this device can detect the presence or direction of an oncoming vehicle, and by combining it with an appropriate judgment device, it can realize a danger prediction function. can.

Effect 1 of Intervention 1 As explained above, according to the present invention, the reflected light of the light emitted toward the reflection ↓(n) is detected, and the detected reflection
Since the imaging means is controlled so that the sign is captured at a predetermined position on the screen according to the position of the i+ light, the sign is always captured at the predetermined position even if the attitude of the moving object changes slightly, and the sign is detected accurately. I can do it.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of a sign recognition device according to an embodiment of the present invention, Fig. 2 is a block diagram of the sign recognition device shown in Fig. 1, and Fig. 3 is a block diagram of the sign recognition device shown in Fig. 1. - "Riasenl"
Fig. 4 is an explanatory diagram showing the image formation position of the repulsed light on the
An explanatory diagram of the case where the distance to the anti-04 mirror is screened in the sign recognition device shown in the figure, FIG. 5 is a flowchart showing the operation of the sign recognition device of FIG. It is an explanatory view when applied to detecting an oncoming vehicle at an intersection. DESCRIPTION OF SYMBOLS 1...Vehicle, 3...Road sign, 5...Anti-13J mirror, 7...Movable pedestal mechanism, 7a...Tilt angle adjustment mechanism, 7b...Pan angle adjustment mechanism, 9... - Light emitting source 11... image carrier S;! 13...Zoom up lens, 17...Half mirror 21...Area sensor, 23...Actuator controller, 25a...Tilt angle sensor, 25b...Pan angle sensor, 27...・Sick stop device 20... No stray electricity.

Claims (1)

[Claims] A sign recognition device that is mounted on a moving object and detects a sign that has a reflecting mirror that is present in the moving direction of the moving object, the device comprising an imaging means that takes an image of the sign, and a light emitting device that emits light toward the reflecting mirror. a detection means for detecting reflected light from the reflecting mirror of light emitted from the light emitting source, and the imaging means captures the label at a predetermined position according to the position of the reflected light detected by the detection means. A sign recognition device comprising: a control means for controlling the imaging position of the imaging means.