JP2008033477A - Control method of unattended carriage - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a control method appropriate to move an unattended carriage by a hand-push operation for the unattended carriage. <P>SOLUTION: Since a hand operation mode where an angle sensor 30, which detects an angle to be made between a direction of a main body of the unattended carriage 1 and a direction of a drive wheel 2, is disposed and the drive wheel 2 is steered so that an angle detected by the sensor 30 is always set to zero, in the hand operation mode, the direction of the carriage 1 and the direction of the drive wheel 2 always coincide with each other, and the direction of the drive wheel 2 always towards the direction to which the carriage 1 is desired to be moved in hand-pushing the main body of the carriage 1 while changing the direction of the carriage by the hand-push operation. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a control method for an automatic guided vehicle. In particular, it is suitable when the automatic guided vehicle is moved by a manual push operation.

As described in Patent Document 1, the automatic guided vehicle automatically travels along the marking line (autonomous traveling) while detecting with a sensor a marking line laid on the floor surface as a route to travel. The character of equipment is extremely strong.
Therefore, when using the automatic guided vehicle, it has not been considered to move the automatic guided vehicle by a manual push operation.
As the arrangement of the wheels in the automatic guided vehicle, for example, two types shown in FIGS. 4 and 5 are conceivable.

That is, in the automatic guided vehicle shown in FIG. 4, the driving wheel 2 that also serves as a steering wheel is disposed near the center front of the vehicle body 1, and the driven wheels 3 a and 3 b that cannot change the direction are disposed on the left and right sides of the vehicle body 1. In addition, driven wheels, so-called caster wheels 4a and 4b, which can be freely changed in direction, are disposed on both the front left and right sides of the vehicle body 1.
Alternatively, in the automatic guided vehicle shown in FIG. 5, driving wheels 2 that also serve as steering wheels are disposed near the center front of the vehicle body 1, and driven wheels 3 a and 3 b that cannot change the direction are disposed on the left and right sides of the vehicle body 1. The front of the vehicle body 1 has a structure in which wheels are omitted.
JP 2000-99145 A

  There are two possible operations for the direction of travel when manually pushing the automatic guided vehicle.

(1) The steering angle is instructed by operating the operation buttons.
Since the steering angle and the direction in which the automatic guided vehicle body should travel do not necessarily match, if the automatic guided vehicle travels a little while giving a steering instruction and the traveling direction of the automatic guided vehicle does not match the intended direction, further steering instructions And the traveling direction of the automatic guided vehicle is corrected so that the automatic guided vehicle is advanced in the desired direction. That is, it is assumed that an operation including trial and error is performed.
Also, when an abnormality occurs in an automated guided vehicle, a manual push operation is required, but it is very rare to carry an operation terminal. The loss time of bringing

(2) The steering angle is instructed by operating the steering wheel.
Compared to the operation button operation, the operation feeling is excellent, but it is necessary to provide a handle for the steering operation, and this method cannot be applied when the installation space cannot be secured.

  A control method for an automatic guided vehicle according to claim 1 of the present invention that solves the above-described problem is that an automatic guided vehicle main body is connected to one driving wheel by a turning shaft, and the driving wheel is turned as a steering wheel by turning of the turning shaft. In an automatic guided vehicle that automatically travels by steering control that steers in an arbitrary direction and travel control that drives and rotates the drive wheel, the direction of the automatic guided vehicle body and the direction that the drive wheel faces are formed. An angle sensor for detecting an angle is provided, and a manual operation mode for steering the drive wheels is provided so that the angle detected by the angle sensor is always zero.

  A control method for an automatic guided vehicle according to a second aspect of the present invention for solving the above-mentioned problems is characterized in that, in the first aspect, the traveling control is stopped in the manual operation mode.

  The automatic guided vehicle control method according to a third aspect of the present invention for solving the above-described problems is that, in the first aspect, the automatic guided vehicle is detected by the angle sensor when the traveling control is disabled. The steered wheel is steered so that the angle is always zero.

  According to the control method of the automatic guided vehicle according to the first aspect of the present invention, the angle sensor for detecting the angle formed by the direction of the automatic guided vehicle body and the direction of the drive wheel is provided, and the direction and the drive of the automatic guided vehicle body A manual operation mode is provided to steer the drive wheels so that the angle formed by the direction of the wheel is always zero, so in the manual operation mode, the traveling direction of the automatic guided vehicle always matches the direction of the automatic guided vehicle body. It became possible to make it.

  According to the control method for the automatic guided vehicle according to the second aspect of the present invention, the same effect as in the first aspect can be obtained, and also when the automatic guided vehicle is moved by a manual push operation by stopping the traveling control, It has become possible to make the traveling direction of the transport vehicle always coincide with the direction of the automatic guided vehicle body.

  According to the control method for the automatic guided vehicle according to the third aspect of the present invention, the same effect as in the first aspect can be obtained, and when the automatic guided vehicle is moved by a manual push operation when the traveling control is disabled. In addition, the traveling direction of the automatic guided vehicle can always coincide with the direction of the automatic guided vehicle body.

    Hereinafter, the mode described as the first embodiment is the best mode for carrying out the present invention.

A first embodiment of the present invention will be described below with reference to FIGS.
FIG. 1 is a steering system diagram of the automatic guided vehicle in the present embodiment, FIG. 2 is a layout diagram of wheels and angle sensors in the present embodiment, and FIG. 3 is a flowchart of a manual operation mode by switch operation in the present embodiment.

As shown in FIG. 1, a manual operation mode switch 20, an angle (steering angle) sensor 30, and a steering motor 40 are connected to the automatic guided vehicle control device 10.
The manual operation mode switch 20 is a switch that gives a manual operation mode command to the automatic guided vehicle control device 10. The manual operation mode is a mode in which steering control is performed to enable steering so that the direction of the drive wheel 2 that also serves as the steering wheel matches the direction of the automatic guided vehicle body.

  As shown in FIG. 2, the drive wheel 2 is arranged near the center front of the automatic guided vehicle 1, and is connected to the vehicle body by a drive wheel connecting shaft (swivel shaft) 5. Therefore, by turning the drive wheel connecting shaft 5 in a horizontal plane, the drive wheel 2 can be steered in any direction as the steering wheel. The steering control is performed by giving a steering instruction to the steering motor 40.

The drive wheel connecting shaft 5 is provided with an angle sensor 30 that detects an angle formed by the direction of the automatic guided vehicle body and the direction in which the drive wheel 2 faces (difference in angle, hereinafter referred to as a steering angle). The detected steering angle is output to the automatic guided vehicle control device 10.
The drive wheel 2 has a structure that is free from rotation so that it does not become a resistance to a manual pressing operation when the travel control is not performed or when the travel control is impaired and becomes impossible.

As shown in FIG. 2, in the automatic guided vehicle 1, driven wheels 3a and 3b whose directions cannot be changed are arranged on the left and right sides of the rear. As shown in FIG. 4, the automatic guided vehicle 1 may further include caster wheels, so-called driven wheels 4a and 4b whose directions can be freely changed, on the left and right sides of the front.
With such a wheel arrangement, the direction of the automatic guided vehicle can be easily changed manually. Further, the driven wheels 3a and 3b arranged at the rear may be structured such that their orientation can be changed in the same manner as the caster wheels 4a and 4b during manual operation.

The automatic guided vehicle control device 10 includes a steering control arithmetic device 10a that performs steering control in the manual operation mode. When the manual operation mode is commanded by the manual operation mode switch 20, the steering detected by the angle sensor 30 is detected. A steering instruction is given to the steering motor 40 so that the angle becomes zero.
That is, in the manual operation mode, the steering control arithmetic device 10a moves the driving wheel 2 of the driving wheel connecting shaft 5 so that the direction of the driving wheel 2 coincides with the direction of the automatic guided vehicle body according to the flowchart shown in FIG. Turn around and perform steering control.

First, when the manual operation mode switch 20 is operated to instruct the manual operation mode to the automatic guided vehicle control device 10 (step S1), the mode is shifted to the manual operation mode, and the direction of the drive wheel 2 coincides with the direction of the automatic guided vehicle. Is determined (step S2).
When the direction of the driving wheel 2 does not coincide with the direction of the automatic guided vehicle, that is, the steering angle detected by the angle sensor 30 (difference in angle between the direction of the automatic driving vehicle 2 and the direction of the automatic driving vehicle 2). When it is not zero, the driving wheel 2 is connected to the driving wheel connecting shaft so that the direction of the driving wheel 2 coincides with the direction of the automatic guided vehicle body, in other words, the steering angle detected by the angle sensor 30 becomes zero. The steering control is performed by turning around 5 (step S3).

On the other hand, when the direction of the driving wheel 2 coincides with the direction of the automatic guided vehicle, that is, when the steering angle detected by the angle sensor 30 is zero, the steering control is skipped.
Subsequently, it is determined whether or not there is a travel instruction (step S4). When there is a travel instruction, travel control for driving and rotating the drive wheels 2 is performed, and the automatic guided vehicle travels (step S5).

Therefore, when the automatic guided vehicle 2 is driven to rotate and travels the automatic guided vehicle, if the direction of the automatic guided vehicle 1 is changed manually, the steering angle detected by the angle sensor 30 becomes zero. Steering control is performed so that the direction of the driving wheel 2 matches the direction of the transport vehicle 1.
Thus, when there is a travel instruction, it is not necessary to manually push the automatic guided vehicle.

On the other hand, if it is determined in step S4 that there is no travel instruction, the travel execution in step S5 is skipped.
Therefore, when the automatic guided vehicle is manually pushed while changing the direction of the automatic guided vehicle, the steering angle detected by the angle sensor 30 becomes zero, that is, the direction of the driving wheel 2 in the direction of the automatic guided vehicle 1. Thus, the automatic guided vehicle 1 is manually pushed while the steering control is performed.

In this way, when the direction of the automatic guided vehicle 1 is directed to the direction in which the automatic guided vehicle 1 is desired to move, the drive wheel 2 that is a steered wheel is steered so as to coincide with the direction of the automatic guided vehicle main body 1. It is possible to easily move the transport vehicle in the direction in which it is desired to move.
Thereafter, when the manual operation mode is stopped (OFF) while the vehicle is stopped, the manual operation mode is shifted to the normal travel mode in which both the travel control and the steering control are enabled (step S6).

In the above-described manual operation mode, when it is determined that there is no travel instruction in step S4, the travel control for driving and rotating the drive wheels 2 is stopped, but the travel control is disabled for some reason. Even in this case, the same steering control may be performed.
For example, when travel control is impaired in the event of an emergency, steering is detected by the angle sensor 30 so that the direction of the drive wheels 2 coincides with the direction of the automatic guided vehicle body, as in the above-described manual operation mode. Steering control is performed by turning the drive wheel 2 around the drive wheel connecting shaft 5 so that the angle becomes zero (see step S3).

  When such steering control is performed, the direction of the driving wheel 2 that is a steered wheel matches the direction of the automatic guided vehicle 1, and as a result, the direction of the automatic guided vehicle 1 matches the direction to be moved. It is effective when the automatic guided vehicle is retreated by changing the direction by manual operation.

  The present invention relates to a method for controlling the traveling direction of an automated guided vehicle, and is suitable for use in an automated guided vehicle that is moved by a manual push operation.

It is a steering system diagram of the automatic guided vehicle in the 1st example of the present invention. FIG. 3 is a layout view of wheels and angle sensors in the first embodiment of the present invention. It is a flowchart which shows the manual operation mode by switch operation in 1st Example of this invention. It is a layout view of wheels in the automatic guided vehicle. It is a layout view of wheels in the automatic guided vehicle.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Automatic guided vehicle 2 Drive wheel 3a, 3b Drive wheel 4a, 4b Drive wheel (caster wheel) which can change direction freely
DESCRIPTION OF SYMBOLS 5 Drive wheel connecting shaft 10 Automatic guided vehicle control apparatus 10a Steering control calculating apparatus 20 Manual operation mode switch 30 Angle (steering angle) sensor 40 Steering motor

Claims (3)

Steering control in which one driving wheel is connected to the automatic guided vehicle body by a turning shaft, and the driving wheel is steered in an arbitrary direction by turning the turning shaft, and traveling by driving and rotating the driving wheel. In an automatic guided vehicle that automatically travels by control, an angle sensor that detects an angle formed between the direction of the automatic guided vehicle body and the direction in which the drive wheel faces is provided, and the angle detected by the angle sensor is always zero. A control method for an automatic guided vehicle, wherein a manual operation mode for steering the drive wheels is provided. The method for controlling an automatic guided vehicle according to claim 1, wherein the traveling control is stopped in the manual operation mode. The automatic guided vehicle according to claim 1, wherein the automatic guided vehicle steers the steering wheel so that an angle detected by the angle sensor is always zero when the traveling control is disabled. Control method.

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