JPS63147205A - Detecting device for guiding direction - Google Patents

Abstract

PURPOSE:To simply set a driving course of a carrier without receiving the disturbance like dust, etc., by photographing a guide line by means of an image pickup device set on the carrier and adding these picture signals in the vertical or horizontal direction to obtain a circumferential distribution curve and to calculate the position of said guide line. CONSTITUTION:The anlog signals outputted from an ITV camera 1 that image picked up a quide line are converted into digital signals by an A/D converting circuit 2. These digital signals are added together in the vertical direction to the scanning direction and a circumferential distribution is obtained by an adder circuit 3, This circumferential distribution is differentiated by a differentiation circuit 4. These maximum and minimum values of differentiation are corresponding to the right and left ends of the guide line and therefore detected by a maximum/minimum position circuit 5. The center value of the guide line is obtained by a line position arithmetic circuit 6 for steering control of a carrier. Then a guiding direction detector is also available even with a curved guide line by dividing horizontally those digital signals into several group instead of addition equivalent to a single screen. Thus the carrier is guided with no disturbance of dust, etc., since the center differentiation value is obtained and furthermore the driving course of the carrier is simply set.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a guidance direction detection device suitable for detecting the traveling direction of a guided vehicle running along a guidance line, for example.

(Prior Art) Conventionally, there are the following methods for guiding automatic guided vehicles. In other words, ■Electromagnetic induction method: A method in which a magnetic sensor detects the magnetic field generated from electromagnetic induction wires buried or laid on the floor.

■Magnetic induction method: A method of moving while detecting a magnetic guide buried or laid in the floor using a magnetic sensor. ■Optical reflection guidance method: A method in which an optical reflective tape attached to the floor or ceiling is exposed to light, the reflected light is received, and the tape moves while detecting the position of the tape.

However, in the case of the electromagnetic induction method in item (2) and the magnetic induction method in item 0, installation work for the 1lEffi induction wire or magnetic guide is difficult. In addition, when changing the route, construction work to reinstall these items is required. Furthermore, the optical reflection guidance method described in item (2) has the disadvantage that it is susceptible to external disturbances such as dust on the reflective tape. Furthermore, in all three methods, the detection point is directly above or below the carrier, making it difficult to stabilize the vehicle. Therefore, there is a problem that the speed of the transport vehicle cannot be increased.

(Problems to be solved by the invention) The present invention has been made by focusing on the above-mentioned problems.
The purpose of the present invention is to provide a guiding method for a conveyance vehicle that allows easy installation and change of the travel route of the conveyance vehicle, provides stable travel, and increases speed.

[Structure of the invention]

(Means and operations for solving the problem) An imaging means for imaging a guidance line for guiding a traveling vehicle, and a marginal distribution calculation means for calculating a marginal distribution curve based on an image signal output from the imaging means. , and position calculation means for detecting the position of the guiding line based on the above-mentioned peripheral distribution curve MK, thereby avoiding the influence of disturbance.

(Example) Hereinafter, one embodiment of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows the guidance direction detection device of this embodiment. This device uses, for example, a guidance line (L) drawn on the floor.
), an A/D conversion circuit (2) that converts the analog image signal 8A output from the ITV camera (1) into a digital image signal SB, and this A/D conversion circuit. The digital image signal SB output from (2) is added vertically to the input image vertical differentiation circuit (
The maximum/minimum position detection circuit (5) calculates the horizontal address with the maximum value and the minimum value from the output result of step 4), and the maximum and minimum values output from this maximum/minimum position detection circuit (5). It consists of a line position calculation section (6) that calculates the position of the guidance line from the address and outputs the calculation result to the steering control section (7) of the guided vehicle. Thus, the differential circuit (4), the maximum/minimum position detection circuit (5), and the line position calculation circuit (6) constitute a guided line detection section (8).

Next, the operation of the guidance direction detection device of this embodiment will be described.

When the I'ff camera (1) captures an image of the guidance line in front of the transport vehicle, the guidance line appears as shown in Figure 2.

The image signal of this ITV camera (1) is converted to an A/D conversion circuit (
2) converts it into a digital image signal. Next, the vertical peripheral distribution of the input image is determined using this digital image signal. Thus, in FIG. 1, the images taken by the ITV camera are converted into digital image numbers (1, 1), (2, 1) by the conversion circuit (2).

(3,1), (4,1)..., (1,2), (2
, 2), . . . are output in this order. This image signal for one screen (out of i, D, i=i, that is, ('as 1)
Add all the image signals of + (ias 2) + ('os 3)e... This is i=1. i=2. i=
3. When NAK is performed as . . . , the vertical peripheral distribution is obtained.

On the other hand, to obtain the peripheral distribution in the horizontal direction, add all the image signals of %J=JO, that is, (1, jo), (2-jo), (3, jo), etc., and add this to j=1. j=2. j
-3, . . . in this order. Now, the addition circuit (3
), the vertical peripheral distribution of the digital image signal output from the ~Φ conversion circuit (2) is determined and the result is output. For example, the vertical peripheral distribution in Fig. 3 is as shown in Fig. 7s4.

Next, the output of the adding circuit (3) is differentiated by a differentiating circuit (4) (the difference with the adjacent pixel is taken). When the marginal distribution shown in FIG. 4 is differentiated, it becomes as shown in FIG. 5. Set the maximum value and minimum value addresses iMAX and iMIN of this result to the maximum -
It is determined by the minimum position detection circuit (5). This maximum value.

The minimum value addresses iMAX and iMIN correspond to the left and right ends of the appeal line (L) in FIG. 3. Therefore,
In the line position calculation circuit (6), iMAX, iMIN
Find the center value of and calculate the position of the guiding line (L). Based on the position of this guidance line (L), the conveyance vehicle performs steering control.

As described above, the guidance direction detection device of this embodiment is
The peripheral distribution of the image captured by the camera (1) is determined, and the position of the guiding line (L) is calculated using the result, so it is relatively resistant to disturbances caused by dust, etc. on the guiding line (L). . This will be explained using diagram M6 as an example.

The vertical peripheral distribution of this figure 6 is as shown in figure 7,
The result obtained by differentiating this is shown in Fig. 8.

If we find the maximum and minimum addresses ``MeiN'' in Figure 8, they will be almost the same values as 'MAX and fMIN in Figure 5.Also, to install a route, simply tape it on the floor or ceiling. It's easy to make changes.

In the above embodiment, only the vertical peripheral distribution was taken to detect the position of the guiding line, but if the horizontal peripheral distribution was similarly taken, the position of the guiding line (L) as shown in Fig. 9 was detected. can also be detected. Furthermore, by determining the peripheral distribution in the vertical and horizontal directions, it is also possible to determine the position of the intersection when the guiding lines intersect, as shown in FIG. In addition, in the above embodiment, one peripheral distribution was obtained using all the image signals for one screen, and the position of the guiding line was obtained, but as shown in FIG. It is also possible to divide the area into a plurality of areas, determine the peripheral distribution for each area, and determine the position of the guiding fin. If this method is used, it can be used even if the guiding line (L) is bent.

〔Effect of the invention〕

The guidance direction detection device of the present invention can reliably detect the guidance direction without being disturbed by dust or the like on the guidance line. Therefore, the traveling route of the transport vehicle can be easily installed and changed, stable travel is possible, and the traveling speed can also be increased.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram of a guidance direction detection device according to an embodiment of the present invention, FIGS. 2 to 5 are diagrams similarly showing detection of the guidance direction,
6 to 11 are explanatory diagrams of other embodiments of the present invention. (1): ITV camera (imaging means). (3): Addition circuit (marginal distribution calculation means). (8) :9-leading in detection section (position calculation means). Agent Patent Attorney Nori Chika Closed Kikuo Takehana Figure 1 IT camera field of view Figure 3 Figures 4 and 7 Figure 10 Figure 8 Figure 11 VA

Claims (1)

[Claims] an imaging means provided on a traveling vehicle guided along a guiding line for capturing an image of the forward side of the traveling vehicle of the guiding line and outputting an image signal; a marginal distribution calculation means for calculating a marginal distribution curve by adding in at least one of the horizontal directions; and a position calculation for calculating the position of the guide line based on the marginal distribution curve determined by the marginal distribution calculation means. A guidance direction detection device comprising: means.