JP2001318718A - Trackless automatic carrier and control method of automatic carrier - Google Patents

Abstract

(57) [Summary] [PROBLEMS] An automatic vehicle that can travel a predetermined route unattended and easily change a route in order to carry parts assembled in a production factory or the like and transport it to a predetermined place. Provision of transport vehicles. The automatic carrier has left and right wheels (2a, 2b).
Tachometers 4a and 4b are attached to
Are connected to the control device 10, and detectors 5a, 5b are attached to the front and rear of the vehicle side and connected to the control device 10, and the automatic guided vehicle is provided with correction plates 9a, 9b,. The vehicle can travel while being detected by both detectors 5a and 5b.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an unmanned automatic guided vehicle used in a production factory or the like, and relates to a trackless automatic guided vehicle capable of easily changing a traveling route of the automatic guided vehicle and a control method thereof. Things.

[0002]

2. Description of the Related Art Today, unmanned automatic transport vehicles are frequently used in production factories and the like, and necessary parts can be loaded and transported to a predetermined place. By the way, the conventional automatic guided vehicle has a magnetic or optical sensor, and is configured so that the vehicle body can be steered by using the magnetized or reflected light emitted from the traveling road surface as a guide signal, and parts and semi-finished products are loaded on the loading platform. It can be carried to a predetermined place without driver. That is,
The guidance method is called a “fixed route method”.

However, when the parts to be manufactured change, the production line is often changed. Therefore, the place where the parts are transported changes. Therefore, a magnetic tape, an optical tape, a cable, or the like laid on the traveling road surface is changed. It must be removed and laid again along the new route. Therefore, when there are frequent changes in the transport parts, the conventional fixed path method is inconvenient, and the change requires a large cost. That is, it is necessary for the automatic guided vehicle to be able to flexibly respond to changes in the traveling route.

Therefore, a method of guiding an automatic guided vehicle called a "pathless method" has been developed in recent years. This “pathless method” does not require a guide on the floor or the like, is not affected by the state of the floor surface, can travel on a predetermined traveling path, and can easily change the traveling path. When the vehicle deviates from the traveling route, self-recovery is also possible. Therefore, a plurality of reflectors, which are known points, are arranged in an area where a traveling path is provided, and a laser beam is radiated to the surroundings from a laser navigator device installed on an automatic transport vehicle to impinge on the reflectors. Three
The position and orientation of the automatic guided vehicle can be calculated from the principle of triangulation by receiving the laser beam that has returned after hitting the reflectors at more than a certain point with the navigator device.

[0005] However, this automatic transport system requires a high-precision laser detector, a high-speed arithmetic unit, and the like in order to confirm and correct the position of the automatic transport vehicle, so that the system becomes very expensive. In addition, it is necessary to install a number of reflectors for reflecting the laser light emitted from the automatic transport vehicle in the traveling area, and furthermore, it is necessary to provide the reflector at a certain height so that the laser light is applied. In some cases, it may be an obstacle to block the traffic.

[0006]

As described above, the conventional automatic carrier has the above-mentioned problems. The problem to be solved by the present invention is this problem, and provides a trackless automatic guided vehicle that can change the traveling route easily without installing many reflectors, and a control method thereof.

[0007]

SUMMARY OF THE INVENTION A trackless automatic transport vehicle according to the present invention is a truck that can travel unattended and carry parts and the like to a predetermined place. However, the method of guiding an automatic guided vehicle according to the present invention is a pathless method, and does not lay a magnetic tape or an optical tape on a traveling route as in the related art. Further, it is not necessary to install many reflectors for reflecting the laser beam emitted from the automatic transport vehicle in the traveling area.

[0008] The automatic transport vehicle of the present invention is equipped with a gyro, a wheel tachometer, and a control device, and is provided with detectors on front and rear sides. Then, a correction plate is arranged on the traveling route at a predetermined interval in parallel with the route. By the way, when the automatic transport vehicle starts traveling, the distance from the correction plate arranged at the start point is read by the two front and rear detectors, and the distance between the automatic transport vehicle and the correction plate is determined in advance. Find the position of the car.

When the wheels are rotated by the motor, the automatic transport vehicle moves, but the moment when the detection point deviates from the correction plate is captured, and the position of the automatic transport vehicle at this time is determined. Thereafter, the automatic guided vehicle travels along a predetermined route with the rotation speeds of both wheels controlled, and approaches the next correction plate.
The position to the next correction plate can be determined by the autonomous traveling calculation, but the edge of the correction plate can be captured by the detector attached at the head. At this time, in order to prevent other members from being erroneously recognized as correction plates, when a plane corresponding to a certain distance is detected, it is recognized as a predetermined correction plate.

The automatic transport vehicle recognizing the edge of the correction plate moves further, and two detectors detect the distance between the automatic transport vehicle and the correction plate, so that the distance and direction to the correction plate can be known. However, since the position and orientation of the correction plate are known in advance, the vehicle travels after correcting the actual position of the automatic transport vehicle by measurement. Thus, the automatic transport vehicle can travel to the destination while correcting the position with the correction plate. Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

[0011]

FIG. 1 is a schematic diagram showing an automatic carrier according to the present invention. Although the size and form of the transport vehicle are not limited, the automatic transport vehicle 1 has four wheels 2a, 2b..., And the upper surface of the transport vehicle 1 is a loading platform 3 on which components and the like are placed.
The wheels 2a, 2b,... Are driven to rotate by motors, so that the automatic guided vehicle 1 can travel. And a tachometer 4 on the wheel axle
a, 4b are attached, and the rotation speed of the wheels 2a, 2b, that is, the traveling distance can be recognized by the rotation speed.

The automatic guided vehicle has a control device 10, and the control device 10 includes a storage unit. The control device can control the number of rotations of the motor based on data in the storage unit. As the motor, a servomotor whose rotation speed is easy to control is suitable. By using the servomotor, it is not necessary to separately install the tachometer 4.

Here, the front wheels 2a and 2b are driven to rotate by separate motors so that they can rotate independently of each other, and the vehicle can run on a curve while changing the number of rotations. Of course, both wheels 2a, 2b may be driven by a single motor via a differential gear,
The drive mechanism of 2b is not particularly limited. Detectors 5a and 5b are attached to the side of the automatic guided vehicle 1 in front and rear, and can detect the distance to a correction plate disposed along the traveling route. .

A predetermined route along which the automatic guided vehicle 1 travels is stored in the storage unit of the control device 10, and the control device 10 can control the number of rotations of the wheels based on data in the storage unit. I can do it. Here, the method of storing the traveling route of the automatic guided vehicle 1 is not particularly limited,
For example, by causing the automatic guided vehicle 1 to actually travel, the rotational speeds of both wheels and the positional relationship with the correction plate disposed along the traveling route can be easily stored.

The automatic transport vehicle 1 shown in FIG. 1 is provided with an input device 6, and the operator can operate the lever by operating the lever 7 of the input device 6. Therefore, the operator drives along the predetermined route from the start point to the end point,
The predetermined route is stored in the storage unit by this one trial run. Of course, it is also possible to theoretically determine the movement locus of the automatic guided vehicle 1 as XY coordinates with the start point as a base point,
This theoretical trajectory may be stored in the storage unit as a traveling route.

FIG. 2 shows a specific example in which the automatic guided vehicle 1 moves along the travel route 8.
Are upright at predetermined intervals along the vertical axis. Of course, the correction plate 9 is also provided at the starting point.
The automatic transport vehicle 1 is stopped at a predetermined distance from the correction plate 9a. When the automatic guided vehicle 1 starts traveling, the correction plate 9 placed at the start point
By reading the distance from “a” with the two detectors 5a and 5b before and after, the position of the automatic transport vehicle 1 can be obtained in accordance with the position of the correction plate 9a which is known in advance. Even at the start point, the automatic guided vehicle 1 is slightly displaced from the position stored in the storage unit.

Then, while the wheels are rotated by the motor, the automatic transport vehicle 1 moves, but the moment when the detection point deviates from the correction plate 9a is captured, and the position of the automatic transport vehicle 1 at this time is determined. Thereafter, the automatic guided vehicle 1 controls the rotation speeds of both wheels, travels along a route previously stored in the storage unit, and approaches the next correction plate 9b. Although the position up to the next correction plate 9b can be determined by the autonomous traveling calculation, the edge of the correction plate 9b can be detected by the detector 5a attached at the head. At this time, in order to prevent other members from being mistaken for the correction plate 9b, the predetermined correction plate 9
b, and if it is determined that the surface is a curved surface, it is not recognized as the correction plate 9b.

The automatic transport vehicle 1 recognizing the edge of the correction plate 9b moves further, and the two detectors 5a and 5b detect the distance between the automatic transport vehicle 1 and the correction plate 9b. The distance and the direction of the automatic guided vehicle 1 with respect to 9b are known. However, since the position and orientation of the correction plate 9b are known in advance, the vehicle travels with the measured actual position and orientation of the automatic transport vehicle 1 correctly corrected. As described above, the automatic transport vehicle 1 can travel to the destination while correcting the position with the correction plate 9.

FIGS. 3A to 3C show the automatic transport vehicle 1 and the correction plate 9.
The relationship is shown. (a) is a case where the automatic transport vehicle 1 is stopped along the correction plate 9a disposed at the start point. At this time, the detector 5a and the correction plate 9a provided on the side surface of the automatic transport vehicle 1 are provided. The distance between them is La, and the distance between the detector 5b and the correction plate 9a is Lb. (b) is a case in which the automatic guided vehicle 1 starts moving, and the detection point of the leading detector 5a deviates from the correction plate 9a.

At this time, the distance between the detector 5a and the correction plate 9a is La, and the distance between the detector 5b and the correction plate 9a is Lb. As described above, at the moment when the detection point of the leading detector 5a deviates from the correction plate 9a, the position and the direction on the traveling route of the automatic guided vehicle 1 are determined. That is, since the correction plate 9a stands at a predetermined position, the position of the automatic transport vehicle 1 is determined by knowing the position off the edge of the correction plate 9a. The direction of the automatic guided vehicle 1 is determined by knowing the distance between 5a and 5b. That is, it can be seen whether or not it is parallel to the traveling route 8 and the correction plate 9a.

In this state, the automatic transport vehicle 1 moves to the correction plate 9b shown in (c), but if the direction of the automatic transport vehicle 1 is shifted at the moment of (b), the correction plate 9b
May reach a large distance from the correction plate 9b or may hit the correction plate 9b. Therefore, since the distance from the correction plate 9a to the correction plate 9b is determined,
While moving the distance between the correction plates 9a and 9b, both wheels 2
The rotation speeds a and 2b are controlled to correct the position so as to be in the correct position.

(C) is the moment when the leading detector 5a catches the edge of the correction plate 9b. This moment is predicted based on the rotation speed of the wheels 2a and 2b from a predetermined distance, but is slightly affected by the slip of the wheels 2a and 2b during the actual traveling process and the unevenness of the traveling road surface. An error may occur, and this error can be corrected in the traveling process of moving to the next correction plate 9c.

As described above, in the present invention, the detectors are provided before and after the side of the automatic guided vehicle, and the traveling route is provided with the correction plates at predetermined intervals, and the following effects can be obtained. .

[0024]

The automatic guided vehicle of the present invention has wheels connected to a tachometer, has a control device for controlling the rotation of these wheels, and has a storage unit for storing a traveling route. ing. Therefore, the automatic guided vehicle can travel along the stored route, but the detectors are attached to the front and rear sides, and the correction plates are set up at predetermined intervals along the travel route. Therefore, if the traveling route of the automatic guided vehicle deviates from the stored predetermined route, the positional relationship with the correction plate is corrected by the two detectors to move the traveling route. You can do it.

As described above, according to the present invention, it is not necessary to lay a magnetic tape or the like on the floor of the traveling route, and the route can be changed easily. In addition, detectors are provided before and after the side surface of the automatic guided vehicle, and only a relatively small correction plate is erected along the traveling route, and it is not necessary to arrange many large reflectors that block the inside of the factory. .

[Brief description of the drawings]

FIG. 1 is a schematic view of an automatic carrier according to the present invention.

FIG. 2 is a traveling route of an automatic carrier.

FIG. 3 is a positional relationship between the automatic transport vehicle and a correction plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Transport vehicle 2 Wheel 3 Carrier 4 Tachometer 5 Detector 6 Input device 7 Lever 8 Travel route 9 Correction plate 10 Control device

Claims (2)

[Claims] 1. A tachometer is attached to the left and right wheels of an automatic transport vehicle that can travel unmanned on a predetermined route in order to place parts to be assembled and transport it to a predetermined location in a production factory or the like. At the same time, the tachometer is connected to the control device, and detectors are attached to the front and rear of the side of the carrier and connected to the control device, and the control device has a storage unit, and the traveling route recorded in the storage unit is stored. A trackless automatic transport vehicle characterized in that a correction plate standing up along a traveling route is detected by both detectors based on the detection, and the vehicle travels while comparing and correcting the positional relationship with the correction plate. 2. A method for controlling an automatic transport vehicle, which can unmannedly travel on a predetermined route in order to place a component to be assembled and transport it to a predetermined location in a production factory or the like. The traveling route is stored in the vehicle, controls the rotation of the wheels via the control device, and raises the correction plate at predetermined intervals along the traveling route,
A method for controlling an automatic transport vehicle, wherein the automatic transport vehicle travels while comparing and correcting the positional relationship with a correction plate by detectors provided on front and rear sides of the automatic transport vehicle.