JPS62200407A - Control system for unmanned carrying car - Google Patents

Abstract

PURPOSE:To eliminate the need for providing an additional guiding line and a magnet sensor at each intersection, by providing a detector for detecting an identification signal identified from the second guiding line, on an unmanned carrying car for tracking and running along the first guided line. CONSTITUTION:When the existence of the second guided line 92 has been detected by an output from a comparator 5, an unmanned carrying car is decelerated (during that time, it tracks linearly on the first guided line 91), and simultaneously, starts to measure a running distance (linear distance) in a decelerated state. At the time point when the measured value has reached a prescribed decelerated distance, the linear tracking is stopped and a rotational operation by a prescribed radius of gyration is executed, and simultaneously, a measurement of length of a circular arc drawn by the rotational operation is started. At the time point when the measured value of the circular arc has reached a prescribed set value, band-pass filters 41, 42 are switched to a frequency f2 side, and thereafter, whether a calling-on signal of the frequency f2 has been caught by coils 21, 22 or not is decided, and when it has been caught, the rotational operation is stopped and the linear tracking on the second guided line 92 is started.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to an automatic guided vehicle control system, and in particular, based on a predetermined turning command, the automatic guided vehicle is controlled from tracking travel on a first guide line to The present invention relates to an improvement in a control method that allows the vehicle to move to a tracking run on a second guide line that intersects with the first guide line.

[Conventional technology]

5 and 6 show one side of the control system for an automatic guided vehicle in the prior art, where 91 is a first guide line;
2, a second guide line 93 that intersects the first guide line 91;
In order to transfer the automatic guided vehicle 1 from tracking running on the first guide line 91 to tracking running on the second guide line 92 (or vice versa), additional guide lines are provided at those intersections. These guide wires 91, 9
Induced currents of the same frequency (for example, 1000 Hz) are passed through 2 and 93. Numeral 94 is a magnetic sensor provided for the automatic guided vehicle to detect the position of an intersection, and only one is shown in the figure.

On the other hand, on the automatic guided vehicle l, there is a guide line (for example, a first guide line 91) to be followed when the automatic guided vehicle runs.
A deviation detection device is provided to detect deviation from the
In the device shown in FIG. 5, a pair of coils 21 and 22 are provided on the left and right sides of the induction wire 91, and these coils 21 and 22 induce a predetermined voltage by the induced current flowing through the induction wire 91. However, a predetermined signal corresponding to the difference between these induced voltages (that is, corresponding to the deviation of the automatic guided vehicle with respect to the guide wire) is manually inputted to the microprocessor 6. The microprocessor 6 calculates how far the automatic guided vehicle deviates from the guide line based on a predetermined signal input from the deviation detection device, and determines whether the automatic guided vehicle is running normally based on the deviation calculation process. The speeds of the left and right wheels 81 and 82 necessary for correcting the trajectory are calculated, and commands are issued to accelerate or decelerate the speeds of the left wheel 81 and right wheel 82 based on the speed calculation results. The signals are output to the servo motors 71 and 72, thereby accelerating or decelerating the speeds of the left and right wheels 81 and 82, respectively, thereby making necessary trajectory corrections.

When transferring the automatic guided vehicle from the first guiding line 91 to the second guiding line 92, the automatic guided vehicle moves in a predetermined direction based on instructions from the ground station or a program stored in the automatic guided vehicle. A turning command is issued, and when the automatic guided vehicle detects a signal from the magnetic sensor 94 indicating the location of the intersection under such conditions, the automatic guided vehicle is directed to the first guide line. 91 and follow the predetermined guide wire 9.
3, and then the vehicle is controlled to travel along the second guide line 92.

[Problem that the invention seeks to solve]

However, in the above-mentioned prior art, it is necessary to provide an additional guide line 93 and a magnetic sensor 94 at each intersection, and therefore there is a problem that the equipment on the ground becomes considerably complicated.

[Means for solving problems]

The present invention has been made to solve such problems, and has a first guide line that includes a predetermined identification signal, and a first guide line that includes an identification signal different from the predetermined identification signal. A second guide line is provided, and a detector for detecting an identification signal identified from the second guide line is provided on the automatic guided vehicle that tracks and travels the first guide line. , when the detector detects the identification signal of the second guide line while a predetermined turning command is issued, the automatic guided vehicle is moved away from the first guide line and directed to the second guide line. An automatic guided vehicle control method is provided that controls the automatic guided vehicle to transfer the vehicle.

[For production]

According to the above configuration, the detector detects the identification signal flowing to the second guide line when there is a predetermined bending command, thereby controlling the tracking of the automatic guided vehicle on the first guide line. Will it be canceled and a new tracking system for the second guide line after that? 111, the required rotational movement is performed.

〔Example〕

1 and 2 show a control system for an automatic guided vehicle as an embodiment of the present invention (parts corresponding to FIGS. 5 and 6 are indicated by the same reference numerals), and 91 is The first guide line 92 is a second guide line that intersects the first guide line 91, and these guide lines! 91 and 92 each have a different frequency, i.e. fi (e.g. 900
hertz) and f2 (for example 1100 hertz) are passed.

On the other hand, on the automatic guided vehicle l, in addition to the coils 21 and 22 as the above-mentioned deflection detection device, there are also coils 21 and 22 flowing in a guide wire (for example, 92) that intersects the currently tracked guide wire (for example, 91). Coils 31 and 32 are provided for detecting induced current (eg frequency f2).

In this case, if the first guide wire 91 and the second guide wire 92 are orthogonal, the coils 21 and 22 (coils for detecting deviation with respect to the currently tracked guide wire)
and coils 31 and 32 (coils for detecting the presence of a guide line orthogonal to the currently tracked guide line) are arranged such that their axes are orthogonal to each other. Note that it is not always necessary to provide two of the latter coils 31 and 32, and in some cases, only one may be provided. As shown in FIG. 2, when the automatic guided vehicle approaches an intersection, the coils 31 and 32 installed at the front of the vehicle
The induced current flowing through the second guiding wire 92 causes the
The induced voltages shown in a) are output, these induced voltages are added and input to the comparator 5, and when the input exceeds a predetermined level L, the comparator 5 becomes a high level, the presence of the second guide wire is detected, and a predetermined detection signal is input to the microprocessor 6. Note that 41 and 42 indicate that the outputs of the deflection detection coils 21 and 22 are respectively The bandpass filters are inserted into each circuit manually inputted to the microprocessor 6, and are provided with bandpass filters for frequencies f1 and f2. Switched and connected to the deviation detection circuit.

FIG. 4 shows a flowchart for controlling the travel of an automatic guided vehicle according to the present invention. In step 401, tracking travel is performed on the first guide line 91 (a pair of coils 2
1 and 22 to track the guidance signal of frequency f1).

Now, a turn in a predetermined direction is commanded based on an instruction from the ground station or a program stored on the automatic guided vehicle, and under such a condition, as shown in step 402, the signal from the comparator 5 is If the output detects the presence of the second guiding wire 92, step 40
3, the automatic guided vehicle is decelerated (during which the first
), and at the same time step 40
As shown in FIG. 4, the traveling path 1i! in the deceleration state! Start measuring l (straight line distance). Then, as shown in step 405, when the measured length value reaches a predetermined deceleration distance, step 4
As shown in step 06, the linear tracking up to that point is stopped and a rotation operation is performed at a predetermined rotation radius, and at the same time step 4
As shown in 07, the circular arc (
For example, the length of the circular arc taken by the outer ring starts to increase or decrease (in that case, the length is measured by replacing the rotational speed of the outer ring with a pulse number using a pulse encoder, for example). Then, as shown in step 408, when the length measurement value of the arc reaches a predetermined set value (the time when the automatic guided vehicle is considered to have moved onto the second guide line), the deviation is changed as shown in step 409. Switching the bandpass filters 41 and 42 provided in the detection circuit to the frequency f2 side,
Thereafter, as shown in step 410, the deflection detection coil 2
1 and 22 to determine whether the guidance signal of the frequency f2 has been caught, and if it is determined that the guidance signal has been caught, as shown in step 411, the rotation operation up to that point is stopped and a new guidance signal is started on the second guidance vA92. to start straight-line tracking.

In the above embodiment, eight large conduction currents having different frequencies are used as signals for identifying the first and second induction wires, but such identification signals are not necessarily limited to the induction currents as described above. For example, it is also possible to use an optical identification signal.

7 and 9 show a control system for an automatic guided vehicle as another embodiment of the present invention (parts corresponding to FIGS. 1 and 2 are indicated by the same reference numerals), and 201 202 is the first barcode containing code information A, and 202 is the code information i.
A second barcode containing B, these are affixed to the floor.

The automatic guided vehicle 1 includes a camera lO1 that reads code information of a barcode indicating a travel route, and cameras 102 and 103 that read code information of a barcode that intersects with the currently tracked barcode (in this case, cameras 102 and 1
03 are arranged in the same direction so as to be perpendicular to the camera 101) and the camera 101.1.
Camera controllers 111, 112, and 113 are provided that digitally convert the code information read by the camera controllers 111, 112, and 113 that are output to the microprocessor 6.

FIG. 8 shows a flowchart for controlling the travel of an automatic guided vehicle according to the present invention. In step 501, similarly to step 401, the camera 101 performs tracking travel for the barcode 201 (code information A). be exposed. Then, based on an instruction from the ground station or a program stored on the automatic guided vehicle, a turn in a predetermined direction is commanded, and in such a state, step 50
2, when the barcode 202 (code information B) is detected by the camera 102.103,
Below is step 4 shown in the flowchart of Figure 4 above.
Processing similar to that shown from 03 to 408 is performed.

Next, in step 509, the code information detected from the camera 101 is switched from A to A, and in step 501, it is determined whether code information B is detected (caught) from the camera 101, and the code information B is detected. When this happens, the process proceeds to step 511, where the rotating operation is stopped and tracking travel is started using the barcode 202 (code information B) as a new travel route.

〔Effect of the invention〕

According to the present invention, only a device for detecting intersecting guide wires is provided on the vehicle, and there is no need to provide additional guide wires and magnetic sensors on the ground as in the prior art, which simplifies the additional equipment on the ground. Moreover, it is possible to reliably switch to tracking travel for the intersecting guide lines.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of an on-vehicle device and a ground device for explaining an automatic guided vehicle control system as an embodiment of the present invention; FIG. 2 is a plan view of each device shown in FIG. 1; Figure 3+
a) and (b) are signal waveform diagrams for explaining the output of the detector shown in FIG. 1, and FIG. 4 is a signal waveform diagram for explaining the travel control operation for the on-board device shown in FIG. A diagram showing a flowchart, FIG. 5 is a side sectional view of an on-vehicle device and a ground device for explaining an automatic guided vehicle control system as a conventional technique, and FIG. 6 is a plan view of each device shown in FIG. It is a diagram. FIG. 7 is a side sectional view of an on-vehicle device and a ground device for explaining an automatic guided vehicle control system as another embodiment of the present invention, and FIG. 8 is a side sectional view of the on-vehicle device shown in FIG. 7. FIG. 9 is a plan view of each device shown in FIG. 7, which is a flowchart for explaining the travel control operation. (Explanation of symbols) 1: Automatic guided vehicle, 21, 22: Deflection detection coil, 31, 32
: Coils for detecting intersecting guide wires, 41, 42
: band pass filter, 5 : comparator, 6 : microprocessor, 71 , 72 : servo motor, 81 , 82 two wheels, 91 , 92 : mutually intersecting guide wires, 93 :
Guide line additionally installed at the intersection, 94: Magnetic sensor, 201.202: High code, 101.102, 103: Camera, 111.112
, 113: Camera controller.

Claims (1)

[Claims] 1. A first guide line including a predetermined identification signal, and a second guide line that includes an identification signal different from the predetermined identification signal and intersects the first guide line, and A detector that detects an identification signal identified from the second guide line is provided on the automatic guided vehicle that travels while tracking the first guide line, and when a predetermined turning command is issued, the detector detects the identification signal. is the second
An automatic guided vehicle control method, characterized in that the automatic guided vehicle is controlled to move away from the first guiding line and onto the second guiding line by detecting an identification signal of the guiding line.