JP2001350520A - Travel controller for automated guided vehicle - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a travel controller for an automated guided vehicle which easily detect the vehicle deviating from its travel course without laying any special thing on the ground. SOLUTION: This controller is a travel controller for an automated guided vehicle which is mounted with a vehicle speed detector 3 and a gyro 2 and travels in a guided travel course while computing its position and traveling direction; and the vehicle 1 is provided with a color difference detector 5 which detects a line 6 painted in the travel direction of the travel course and it is decided that the unmanned carriage 1 deviates from the travel course when the input of the detection signal of the painted line 6 from the color difference detector 5 is ceased or when a GPS receiver 8 which measures the current position is mounted on the unmanned carriage 1 and the difference between the current estimated position computed by the vehicle speed detector 3 and gyro 2 and the current position measured by the GPS receiver 8 is larger than a specific value, thereby sending a travel stop signal out.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a traveling control device for an automatic guided vehicle that travels to a destination while recognizing a current position by detecting a change angle and a moving distance with a gyro and a vehicle speed detector. The present invention relates to a control device for stopping traveling when a vehicle deviates from a traveling route.

[0002]

2. Description of the Related Art Conventionally, a gyro detects a traveling azimuth and an encoder detects the number of rotations of a wheel to calculate a traveling position, and guides the vehicle to a target location based on map information mounted on a carrier. Automated guided vehicles are known and do not require the installation of guides such as guide lines or magnetic tapes on the running path, such as electromagnetic induction systems, magnetic induction systems, and optical reflection tape recognition systems. It is particularly suitable for outdoors where the traveling route is long.

In this guidance system, there are errors in the values detected by the gyro and the vehicle speed detector, and the calculation of the change angle and the moving distance is performed by integration. The current position and the direction are shifted. For this reason, the automatic guided vehicle may deviate from the traveling route or may not arrive at the target position.

In order to prevent this, another guide means, for example, a guide tape or an ID tag is installed at the starting point or in the middle of the traveling route, and this is detected by a detector mounted on the automatic guided vehicle, and the current position and the current position are detected. The azimuth deviation is corrected, and a mark is provided at regular intervals on the traveling route so that the automatic guided vehicle detects the sign and travels on the predetermined traveling route.

[0005]

However, in such a method, since the traveling route between the sign points is estimated travel, the automatic guided vehicle travels depending on errors or abnormalities of the gyro, the vehicle speed detector, and the arithmetic processing unit. There is a risk of running off the route.

To prevent this, a guide tape or I
D-tags should be installed at a fine pitch and signs of travel routes should be provided at short intervals to reduce intermittent information from the ground side, but installation on the ground side is too expensive, and unmanned gyro and vehicle speed detectors There is no point in guiding the transport vehicle.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a travel control device for an automatic guided vehicle that simply detects that the automatic guided vehicle has deviated from a travel route without laying a special object on the ground side. Is what you do.

[0008]

In order to achieve the above object, the present invention employs the following means. That is, according to the first aspect of the present invention, there is provided a travel control device for an automatic guided vehicle that travels on a commanded traveling route while calculating its own position and traveling direction by mounting a vehicle speed detector and a gyro that detects a moving angle. An unmanned guided vehicle is provided with a color detector that detects a painted line painted in the traveling direction of the traveling route, and when the detection signal of the painted line is not input by the colored detector, the unmanned guided vehicle moves from the traveling route. It is characterized in that it is determined that the vehicle has deviated, and the vehicle is stopped.

The present invention is mainly applied to an automatic guided vehicle traveling outdoors while calculating its own position and traveling direction by mounting a vehicle speed detector and a gyro. Therefore, those used exclusively for indoor use and those provided with a guide such as a magnetic tape or a guide wire for guiding the automatic guided vehicle on the traveling route for outdoor use are excluded.

In the automatic guided vehicle guidance system, there is an error in the position and direction obtained by calculation from the vehicle speed detector and the gyro, and therefore, a means for appropriately correcting the position and the azimuth is required. In addition, it is estimated travel between signs, and even if the vehicle deviates from the travel route, there is a possibility that it may be judged that the vehicle is within the travel route, and if the automatic guided vehicle deviates from the travel route, it stops immediately. I have to do it.

Normally, the traveling route of the automatic guided vehicle is a dedicated road, and in order to distinguish it from the road of ordinary vehicles, for example, a white line is drawn at the center of the traveling route, or the automatic guided vehicle is located at both ends of the traveling route. A paint color line indicating the traveling range is drawn.
In the present invention, the vehicle travels while detecting this paint line with the color detector provided on the automatic guided vehicle, and when there is no input signal from the color detector, it is determined that the automatic guided vehicle has deviated from the traveling route. It is designed to stop immediately.

The type of the color detector is not limited as long as it can detect colors, such as a color mark sensor, but it must be able to detect even a puddle. The range to be detected is an amount (for example, 30 cm) allowed in the width direction of the traveling route when the automatic guided vehicle travels.
And it is sufficient.

When the paint line is drawn at the center of the traveling route, one color-specific detector may be mounted at the lower center of the automatic guided vehicle, but is drawn on both sides of the traveling route. In this case, it is provided at both ends of the automatic guided vehicle. According to a second aspect of the present invention, there is provided a travel control device for an automatic guided vehicle that travels on a commanded traveling route while calculating a position and a traveling direction of a vehicle equipped with a vehicle speed detector and a gyro that detects a movement angle,
An automatic guided vehicle is equipped with a GPS receiver that measures the current position based on radio waves from GPS satellites, and the difference between the current estimated position calculated from the vehicle speed detector and the gyro and the current position measured by the GPS receiver is determined. When the value is larger than the value, it is determined that the automatic guided vehicle has deviated from the traveling route, and the traveling is stopped.

It is preferable to select a GPS receiver having as high a position accuracy as possible, and it is desirable to provide a means for confirming that the position information obtained from the GPS satellite is correct. For example, it is convenient to install a GPS station on the ground and monitor whether the received position information is constant and transmit the monitoring information to the automatic guided vehicle by radio or the like.

The determination that the automatic guided vehicle has deviated from the traveling route is based on the amount of deviation in the width direction of the traveling route between the current estimated position calculated from the vehicle speed detector and the gyro and the current position measured by the GPS receiver. What should be done is.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below based on an embodiment shown in the drawings. First, the first aspect of the present invention will be described with reference to FIGS. As shown in FIG.
The automatic guided vehicle 1 has a flat loading platform over its entire length, is provided with a plurality of wheels, and each wheel is mounted on an arm with respect to a frame so that the height of the loading platform can be changed by rotating the arm. It is configured. Then, for example, the carrier can be lowered into the legged pallet on which the article is placed, and the carrier can be raised to carry the article along with the legged pallet.

The wheels are configured so that they can be individually steered, and can be traversed or skewed. One of the wheels of the automatic guided vehicle 1 is provided with a vehicle speed detector 3 composed of a rotary encoder for detecting the rotation thereof, and a gyro 2 for detecting a change in the rotation angle is mounted at the center of the vehicle body. . In addition, as shown in FIG. 1A, the center of the automatic guided vehicle 1 is located at a central portion of the automatic guided vehicle 1 opposite to a paint color line (white line) continuously applied to the center of the traveling route 7 of the automatic guided vehicle 1 in the traveling direction. A color mark sensor 5 is provided.

The color mark sensor 5 is a sensor for determining the intensity of reflected light from a detected object as a color difference, and its principle is the same as that of a reflection type photoelectric switch. Although not shown, the automatic guided vehicle 1 is provided with a detector that detects an ID tag or a magnetic tape installed at a point that is a point on the traveling route in order to correct the position and the orientation. A detector for detecting a marker provided at a predetermined interval (80 to 100 m) is mounted. The ID tag is information to which absolute position (X, Y, θ) information of the point is input,
The position information can be obtained by electromagnetic induction from the ID tag detector.

The traveling control device of the automatic guided vehicle 1 is shown in FIG.
As shown in the block diagram of FIG. 1, the control unit includes a detection unit 10, an input unit 20, an arithmetic processing unit 30, and a traveling control unit 40. The input unit 20 is a detection unit 10 provided in the automatic guided vehicle 1.
The arithmetic processing unit 3 incorporates signals from the gyro 2, the vehicle speed detector 3, the ID tag detector 4, and the color mark sensor 5
The signal is converted to a signal that can be easily processed and output.

The arithmetic processing unit 30 takes in the rotation angle detection information from the gyro 2 and the vehicle speed detection information from the vehicle speed detector 3 among the information of the input unit 20, and the arithmetic unit 31 advances the automatic guided vehicle 1 The direction and the moving distance are calculated, and based on the calculation results, the position where the automatic guided vehicle 1 is present is converted into XY coordinates and transmitted to the travel control device 40 via the storage unit 33. In the travel control device 40, steering control and speed control are performed according to the commanded travel route and travel speed.

When the automatic guided vehicle 1 passes through an ID tag provided at a position on the traveling route, electromagnetic induction is performed from the ID tag detector to the ID tag, and the transmission circuit is activated, and the absolute position information is obtained. Is transmitted to the input unit 20. On the other hand, the color mark sensor 5 constantly detects whether or not there is a white line at the center of the travel route 7 within a range of 30 cm in width. If this signal is not transmitted to the input unit 20, the determination of the arithmetic processing unit 30 is made. This is sent to the storage unit 33 and stored in the storage unit 33 in advance.
It is determined whether or not the vehicle is out of the travel route in consideration of the predetermined condition (for example, when the detection is not performed for 30 cm or more) set when the automatic guided vehicle 1 has deviated from the travel route. , And sends a command to stop traveling to the traveling control unit 40.

The color mark sensor 5 only detects whether or not there is a white line, and does not guide the automatic guided vehicle by this detection. Therefore, when there is a margin in the width of the traveling route, the detection range may be considerably increased.
Next, a second embodiment of the invention will be described with reference to FIGS.

The configuration of the automatic guided vehicle 1 is the same as that of the first aspect of the present invention. Parts common to the respective parts shown in FIG. 1B are denoted by the same reference numerals, and description thereof is omitted. I do. Detectors mounted on the automatic guided vehicle 1 for traveling control include a gyro 2, a vehicle speed detector 3, and an ID tag detector 4.
In addition, there is a GPS receiver 8.

That is, the embodiment shown in FIG. 3 differs from the embodiment shown in FIG. 1B in that a GPS receiver 8 is provided instead of the color mark sensor 5. The GPS receiver 8 is a GPS receiver that orbits the Earth's satellite orbit.
The radio wave transmitted from the S satellite is received, and the current position of the automatic guided vehicle 1 can be measured in latitude and longitude based on the radio wave. There are various types of GPS receivers 8. Here, for example, an RTK-GPS (real-time kinematics-global positioning system) having high accuracy of plus or minus several cm is mounted.

When the GPS satellite moves to the rear side of the earth, it switches to another receivable GPS satellite to receive radio waves. In addition, GP
The information from the S receiver may be incorrect, and it is necessary to confirm that the position information is reliable. Here, as shown in FIG. 4, a GPS station 50 having a GPS receiver 52 and a wireless device 53 is provided on the ground side, and the position information of the GPS station 50 is constantly sent to the automatic guided vehicle 1 by the wireless device. I check for fluctuations.
Here, 51 and 8 are shown as GPS antennas.

The traveling control device of the automatic guided vehicle 1 is shown in FIG.
As shown in the block diagram of FIG. 1, the control unit includes a detection unit 10, an input unit 20, an arithmetic processing unit 30, and a traveling control unit 40. The input unit 20 is a detection unit 10 provided in the automatic guided vehicle 1.
Gyro 2, vehicle speed detector 3, ID tag detector 4, GP
The signal from the S receiver 8 is taken in, converted into a signal that can be easily processed, and output to the arithmetic processing unit 30.

The arithmetic processing unit 30 takes in the rotation angle detection information from the gyro 2 and the vehicle speed detection information from the vehicle speed detector 3 and calculates a traveling direction and a moving distance of the automatic guided vehicle 1 in a calculation unit 31. Based on the calculation result, the position where the automatic guided vehicle 1 is currently located is converted into XY coordinates and transmitted to the travel control device 40 via the storage unit 33. Travel control device 40
In, steering control and speed control are performed according to the instructed traveling route and traveling speed.

When the automatic guided vehicle 1 passes through an ID tag provided at a position on the traveling route, electromagnetic induction is performed from the ID tag detector to the ID tag, and the transmission circuit is operated to obtain absolute position information. Is transmitted to the input unit 20. On the other hand, the information on the current position obtained by the GPS receiver 8 is sent to the comparison / determination unit of the arithmetic processing unit 30 and is compared with the current position calculated from the detection information from the gyro 2 and the vehicle speed detector 3. If the difference is equal to or greater than a preset value,
It is determined that the automatic guided vehicle 1 has left the traveling path,
A command to stop running is sent to the running control unit 40. The predetermined value is given as an allowable shift amount with respect to the width of the traveling path on which the automatic guided vehicle 1 is located, based on the map information of the traveling path.

Further, the current position output cycle of the RTK-GPS is 2 Hz to 5 Hz. When the traveling speed of the automatic guided vehicle is increased, a delay error of the output of the position information cannot be ignored. The current position is corrected by the processing unit 30 based on the information of the vehicle speed detector 3.

[0030]

As described above, according to the first aspect of the present invention, there is provided an automatic guided vehicle traveling control device for applying a color line, which is applied to the automatic guided vehicle in a traveling direction of a traveling route, to a color mark sensor or the like. Since it travels while detecting with another detector, there is no need for a special thing on the ground side, and the automatic guided vehicle deviates from the traveling route by simple means of installing a color-based detector on the automatic guided vehicle. Can be determined.

According to a second aspect of the present invention, an automatic guided vehicle is provided with a GPS receiver for measuring a current position based on radio waves from GPS satellites, and a current estimated position calculated from the vehicle speed detector and the gyro and the GPS receiver are used. Compared to the measured current position, it is determined that the automatic guided vehicle has deviated from the travel route, so there is no need to lay any special thing on the ground side, and the route can be changed freely. It is.

[Brief description of the drawings]

FIG. 1 shows a traveling control device of an automatic guided vehicle according to an embodiment of the present invention, wherein (a) is a plan view showing a state of a traveling route, and (b) is a side view of the automatic guided vehicle. is there.

FIG. 2 is a block diagram of the traveling control device.

FIG. 3 is a side view of the automatic guided vehicle according to an embodiment of the present invention.

FIG. 4 is a diagram illustrating correction of a GPS signal.

FIG. 5 is a block diagram showing a configuration of the travel control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Automatic guided vehicle 2 ... Gyro 3 ... Vehicle speed detector 4 ... ID tag detector 5 ... Color mark sensor 6 ... White line 7 ... Travel route 8 ... GPS receiver 10 ... Detector 20 ... Input unit 30 ... Arithmetic processing unit 31 ... Arithmetic unit 32 ... Comparison and judgment unit 33 ... Storage unit 34 ... Judgment unit 40 ... Travel control device 50 ... GPS station 51 ... GPS antenna 52 ... Receivers 53 and 54 ...

Continued on the front page (72) Inventor Mamoru Terada 1-1, Sanbonmatsucho, Atsuta-ku, Nagoya-shi, Aichi Prefecture Inside Japan Vehicle Manufacturing Co., Ltd. (72) Inventor Yoneharu Shibata 1-1, Sanbonmatsucho, Atsuta-ku, Nagoya-shi, Aichi Japan Inside Vehicle Manufacturing Co., Ltd. (72) Inventor Shoichi Takahashi 1-1, Sanbonmatsucho, Atsuta-ku, Nagoya-shi, Aichi Japan Vehicle Manufacturing Co., Ltd. F-term (reference) 5H301 AA01 AA09 BB05 CC03 CC06 FF04 FF06 FF08 FF11 FF13 FF15 FF26 FF27 GG08 GG12 GG14 GG17 MM07 MM09

Claims (2)

[Claims] 1. A traveling control device for an automatic guided vehicle which carries a commanded traveling route while calculating its own position and traveling direction by mounting a vehicle speed detector and a gyro for detecting a moving angle. A color detector is provided for detecting a painted line painted in the traveling direction of the traveling route, and the automatic guided vehicle deviates from the traveling route when the detection signal of the painted line is lost by the color detector. A traveling control device for an automatic guided vehicle, wherein the traveling is stopped. 2. A traveling control device for an automatic guided vehicle that travels on a commanded traveling route while calculating its own position and traveling direction by mounting a vehicle speed detector and a gyro for detecting a moving angle. A GPS receiver that measures the current position based on radio waves from GPS satellites is installed, and the difference between the current estimated position calculated from the vehicle speed detector and the gyro and the current position measured by the GPS receiver is larger than a predetermined value. A traveling control device for an automatic guided vehicle, wherein the traveling control device determines that the automatic guided vehicle deviates from the traveling route and stops traveling.