JPH01297708A - System for controlling travel of unmanned carrier - Google Patents

Abstract

PURPOSE:To arrange a travel space at minimum by arranging a guide tape at right angles by detecting the switching point of a car body in a right or a left direction, and turning the car body at right angles at that point. CONSTITUTION:Sensors (11-13) are provided on right, left and central horizontal lines on an unmanned travel body on the rearward of a reflecting type sensor 10. Meanwhile, a guide tape 3 is provided at a travel path, however, the tape 3 is provided at right angles at a part where the travel body is turned to right or left. Thereby, when the sensor 10 detects no travel body and either the right or the left sensor 12 or 13 and the central sensor 11 detect it after the sensor 10 detects the travel body, it is judged that the turning is performed to a direction detected by the right and the left sensors, and at that point, an unmanned travel vehicle is turned at right angles.

Description

[Detailed Description of the Invention] [Summary] The present invention relates to an automatic guided vehicle that is provided with a reflective sensor on the bottom of the vehicle body, and that detects a guide tape on the road surface and controls the travel thereof, and includes: The purpose of this system is to provide a driving control system for an automated guided vehicle that detects a conversion point and turns the vehicle body.A plurality of reflective sensors are installed at the front center of the bottom of the vehicle body, facing the road surface, and the sensors detect the points on the road surface. In an automatic guided vehicle that detects a belt-shaped guide tape and controls traveling along the tape, a single reflective sensor is provided at the center at a predetermined distance behind the plurality of reflective sensors and on both sides separated by a predetermined interval, When changing the left-right direction of the guiding tape, the tape is set at right angles, and when the side sensor detects the guiding tape to be advanced when changing the left-right direction of the vehicle body, the vehicle body is controlled to turn around the central sensor.

[Industrial application field]

The present invention relates to an automatic guided vehicle that is provided with a reflective sensor on the bottom of the vehicle body, and that detects a guide tape on the road surface and controls the vehicle's travel.

[Conventional technology]

2. Description of the Related Art Conventionally, automatic guided vehicles have been frequently used to transport parts and products during manufacturing processes. As an example of the automatic guided vehicle is shown in FIG. 4 (cL), the vehicle body 1 has, for example, a front wheel and left and right rear wheels, and a plurality of reflective sensors 10 are arranged horizontally at the front center of the bottom surface. establish. Then, the light from the light emitting diode is projected onto a belt-shaped guide tape placed in advance on the running road surface, and the reflected light is received, and the vehicle is automatically controlled to travel along this guide tape. In this case, no human control operation is required.

Control in the direction changing operation of the plurality of reflective sensors 10 is shown in FIG. 4(b). That is, the guide tape 2 in this system is set with a front curve having a relatively large curvature as shown in the figure.

This is because the sensor 10 is divided in parallel in the traveling direction of the vehicle body, and the central sensor 10' always faces the center of the guide tape 2, detecting the amount of deviation between the sensor 10' and the center of the tape. The drive system of the automatic guided vehicle is controlled according to the amount of deviation. For example, the left and right rear wheels are driven in a preset direction and drive count number.

[Problem to be solved by the invention]

In the guiding tape tracking method with the above configuration, as the radius of curvature R of the guiding tape 2 becomes smaller, it is necessary to always keep the curved tape within the detection area of the sensor 10. Therefore, the number of sensors 10 is increased and the unit sensor is It needs to be made smaller.

Furthermore, if the radius R becomes even smaller, the detection control will no longer be able to follow the running on the guide tape, and there is a risk that the vehicle will derail on the guide tape.

On the other hand, if the radius R is made large enough to follow the guide tape, a large installation space is required and it becomes difficult to form a running path in a narrow passage.

The inventor of the present invention considered detecting a direction change point and turning the vehicle body at this point when changing direction.

An object of the present invention is to provide a travel control system for an automatic guided vehicle that detects left and right direction change points and turns the vehicle body.

[Means to solve the problem]

In order to achieve the above object, in the present invention, a plurality of reflective sensors are provided at the front center of the bottom of the vehicle body facing the road surface, and the sensor detects a belt-shaped guidance tape on the road surface and the vehicle runs along the tape. In the automatic guided vehicle to be controlled, as shown in the configuration diagram of FIG. 1(a), a single reflective sensor 11 is provided at the center at a predetermined distance behind the plurality of reflective sensors 10 and on both sides separated by a predetermined distance. , 12.13, and as will be described later in FIG. 1(b) (2) and (2), the horizontal direction conversion of the guide tape should be performed by setting the tape at right angles, and proceeding with the side sensor when the vehicle body is changed in the left and right direction. When the guide tape is detected, the vehicle body turns around the central sensor.

[For production]

As shown in FIG. 1(b)■ and FIG. 1(b)■, when the vehicle body 1 traveling straight on the guidance tape 31 turns left by the tape 3□ in the former case, and when it turns right by the tape 33 in the latter case. be. In this case, the direction change point is detected when the direction sensor 12.13 becomes 1"' while driving straight. If the center sensor 11 is the center at this position, the direction change point is detected. A change in direction is made by turning to the right.

〔Example〕

The gist of the present invention is to detect the direction change of the guide tape with the side sensors 12 and 13, as shown in FIG.
In this respect, turning the sensor around the central sensor 11 is a technique that changes direction at right angles without taking up much space. On the other hand, Fig. 1(b) (2) shows straight nine-circle travel. Similar to the plurality of reflective sensors 10 shown in FIG. 5, this detects the amount of deviation between the center sensor 10' and the center of the guide tape 3, controls the drive system, and travels.

In addition, Fig. 1(b) (■) shows stop control, in which the tape at the position where the stop is to be performed is cut by a distance of 10 mm from the central sensor 11 to the front sensor 10 and the sensor 1
When 1 cannot be detected, the vehicle body is stopped.

FIG. 2 is an explanatory diagram of the control method showing the operating states of the above ■ to ■ in the vertical direction, and the respective states of the front sensor 10 and rear sensors 12, 11, 16 of the vehicle body in the horizontal direction. It is.

In other words, when traveling straight (■), sensor 10 and sensor 11 are 1
The front and rear wheel cloths (R) and the left (L) can be tracked in accordance with the straight line of the guide tape 2 and the curvature that can be detected by the sensor 10, respectively. Therefore,
It can also be applied to conventional induction tape.

The left turn (2) and the right turn (2) are the essential parts of the present invention. ■ After going straight, the sensor 10 becomes 0”, the sensor 1
It is detected when either side sensor 12 or 13 becomes "1" while 1 remains at 1'.

As a result, it is detected that the guide tape to be advanced has turned right or left. At this point, the vehicle body is first stopped (7) and then the driving of the front wheels and rear wheels R and L is controlled so as to turn around the sensor 11. This trough movement direction and drive count value are set in advance in the storage device.

As a result of this turning, the state of each sensor returns to the straight-ahead state shown in (3).

At the stop in ■, after going straight in ■, sensor 10. When the sensor 11 detects that both become 0'', the drive system is stopped.

FIG. 3 is an explanatory diagram of the configuration of a drive system based on the control method shown in FIG. 2.

In the figure, each sensor 10.1 provided on the bottom surface 1 of the vehicle body
The on/off detection signal from 2, 11.13 and the deviation signal from the central sensor 10' from the sensor 10 are converted into digital signals by the A/D converter 20,
U) 21, the program and drive setting values corresponding to each operation mode are read out from the storage device 22 as shown in FIG.
．． It is supplied to the drive systems of the rear wheel (right) '302R and the rear wheel (left) 60□L. Each drive system is composed of similar servo systems that are distinguished by subscripts. That is, after the drive command from the CPU 21 is synchronized with respect to each wheel operation in the synchronization circuit 23, it is converted into an analog drive signal by the D/A converter 24, and the control circuit 25 converts the drive command into an analog drive signal for direction and drive speed. is applied to the drive motor 26 to drive the front wheels 30. And the rear wheels 302R1302L are driven as prescribed. Here, for the rear wheels, when following a curve due to the deviation of ■ in Figure 2, and ■
Since the direction and speed of the left and right rear wheels are different when turning during direction change, as shown in the figure, gearboxes 272R and 27□L are provided in front of the rear wheels 60□R and 302L, respectively.
Drive with different gear ratios is performed.

〔Effect of the invention〕

As explained above, according to the present invention, by detecting the turning point of the vehicle body in the left-right direction and turning the vehicle body at that point, the guiding tape is arranged at right angles to minimize the running space and change the direction. Can be converted.

This eliminates the need for large curvatures and prevents derailment, unlike conventional methods.

The system of the present invention has the advantage that it can be effectively applied even in narrow passages when transporting parts, products, etc. between processes in a manufacturing factory or the like.

[Brief explanation of the drawing]

Figures 1 (α) and (b) are schematic explanatory diagrams of the present invention;
The figure is an explanatory diagram of the control method of the present invention, Figure 3 is an explanatory diagram of the configuration of the drive system of the present invention, and Figure 4 (L:L) and (b) are explanatory diagrams of the conventional example. 1 is the bottom of the car body, 3 + 31
+ 32 is the guide tape, 10 is the front sensor, 10' is the center sensor, 11 is the rear center upper sensor, 12.13 is the rear side sensor (R, L), 20 is the A/D converter, 21 is the Central processing unit (CPU), 22 a storage device, 26 a synchronization circuit, 24 a D/A converter, 25 a control circuit, 26 a drive motor, 27 a gearbox, 301 a front wheel, 30
2R indicates a rear wheel (R), and 302L indicates a rear wheel (L).

Claims (1)

[Scope of Claims] An automatic guided vehicle in which a plurality of reflective sensors are provided at the front center of the bottom of the vehicle body facing the road surface, the sensors detect a belt-shaped guidance tape on the road surface, and the vehicle is controlled to travel along the tape. , a single reflective sensor is provided at the center at a predetermined distance rearward of the plurality of reflective sensors, and on both sides separated by a predetermined distance, and the horizontal direction conversion of the guide tape is performed by setting the tape at a right angle, and the horizontal direction of the vehicle body. An automatic guided vehicle travel control system characterized in that when a guide tape to be traveled is detected by the side sensors at the time of conversion, the vehicle body is controlled to turn around a central sensor.