JP2524179Y2 - Automatic guided vehicle guidance device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electromagnetically guided automatic guided vehicle guiding apparatus for steering and guiding an automatic guided vehicle along a course on a running road surface such as a floor in a factory or the like.

[0002]

2. Description of the Related Art FIG. 4 shows a conventional automatic guided vehicle. The automatic guided vehicle 1 is a truck that is steered and controlled on a course on a traveling road surface 2 provided in a factory or the like, and transports unmanned luggage.

[0003] As a guide device for the automatic guided vehicle 1, first, a guide line 3 as a guide line is buried on a course of a traveling road surface 2 of the automatic guided vehicle 1. The guide line 3 generates a substantially concentric alternating magnetic field 4 as shown by a broken line in FIG. On the other hand, the automatic guided vehicle 1 is provided with a pair of left and right pickup coils 5 and 5 serving as an induction sensor.

The right and left pickup coils 5 and 5 have a ring shape as shown in FIG. 6 and are arranged perpendicular to the road surface 2 at the front end of the automatic guided vehicle 1. The distance A between them is 200 mm, and the height B from the guideline 3 to the left and right pickup coils 5, 5 is set to 150 mm. The left and right pickup coils 5 and 5 detect a change in the magnetic field 4 and generate an induced voltage due to a change in magnetic flux passing through a surface including the coils 5 and 5. When the induced voltage departs from the guideline 3, the induced voltage rapidly decreases in inverse proportion to the square of the distance.

FIG. 7 is a circuit block diagram of the guidance device of the automatic guided vehicle 1. The induced voltages induced in the left and right pickup coils 5 and 5 by the AC magnetic field 4 of the guideline 3 are tuned by the tuning circuit 6 to extract only the components of the target guide frequency, and each is further rectified by the rectifying circuit 7. The left and right rectified induced voltages are compared by the comparison circuit 8. In this way, the steering control is performed while detecting the amount of left and right deviation of the automatic guided vehicle 1 with respect to the guide line 3, and the automatic guided vehicle 1 is guided and guided so that the mutual center of the left and right pickup coils 5 is aligned with the guide line 3. Like that.

[0006]

By the way, in the above-described conventional automatic guided vehicle guiding apparatus, the voltage curve a of the difference between the induced voltages of the left and right pickup coils 5 and 5 becomes a sine wave curve as shown in FIG. From now on, the left and right deviation amounts of the automatic guided vehicle 1 with respect to the guideline 3 are detected and the steering control is performed. However, in the voltage curve a indicating the difference of the induced voltage, the automatic guided vehicle 1 is shifted beyond a certain range. In this case, the left and right pickup coils 5, 5 deviate from the magnetic field 4 of the guide line 3 and become undetectable, and cannot return to the guide line 3. Therefore, the sum of the induced voltages of the left and right pickup coils 5, 5 is determined to detect the guide line 3. It was desired to determine the presence or absence.

However, in the case of the left and right pickup coils 5 and 5 positioned perpendicular to the road surface 2, the voltage curve b of the sum of the mutual induced voltages does not form a mountain shape at the top as shown in FIG. Conversely, it becomes concave. For this reason, it was not possible to take an appropriate threshold value for judging whether or not the guideline 3 of the left and right pickup coils 5 and 5 was detected.

The present invention has been made in view of the above circumstances, and an object thereof is to accurately set a threshold for judging the presence or absence of the guideline detection from the sum of the induced voltages of the left and right pickup coils. , Accurately detects whether the automatic guided vehicle has deviated from the guideline, and can perform guidance by appropriate steering based on the amount of left and right deviation due to the difference in the induced voltage of the left and right pickup coils while preventing runaway And to provide an automatic guided vehicle guidance device.

[0009]

In order to achieve the above object, the automatic guided vehicle guiding apparatus according to the present invention provides a guideline for generating a magnetic field on a course on a traveling road surface of the automatic guided vehicle, A pair of left and right pickup coils that generate an induced voltage are provided on the AGV, and the AGV is detected while detecting the amount of left and right deviation from the guideline of the AGV based on the sum and difference of the induced voltages between the left and right pickup coils. In an automatic guided vehicle guidance device for steering and guiding along a course, a peak-shaped peak in which the sum of induced voltages of the two pickup coils peaks when the center between the left and right pickup coils is positioned on a guide line. In the state where the voltage curve is obtained, the distance between the left and right pickup coils and the inclination angle with respect to each road surface Characterized in that setting the.

[0010]

According to the automatic guided vehicle guiding apparatus having the above construction, the distance between the left and right pickup coils and the inclination angle with respect to each road surface are set as described above, so that the center between the left and right pickup coils is positioned on the guide line. A peak-shaped voltage curve in which the sum of the induced voltages of the two pickup coils is peaked, and a threshold value for judging the presence or absence of the detection of the guideline can be accurately taken, so that the automatic guided vehicle It is possible to accurately detect the presence or absence of the guideline and to perform appropriate guidance such as runaway prevention.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIGS. In the drawings, the same components as those shown in FIGS. 4 to 8 are denoted by the same reference numerals to simplify the description.

FIG. 1 shows an automatic guided vehicle guiding apparatus. 1 in the figure
0 denotes left and right pickup coils. The left and right pickup coils 10 are provided at the front end of the automatic guided vehicle 1,
It has an inclination angle of 45 ° with respect to the road surface 2, is arranged symmetrically in a substantially C-shape, and has a smaller mutual distance than before. That is, the left and right pickup coils 10, 10 are inclined by 90 °.

As shown in FIG. 2, the induced voltage of one pickup coil 10 is a height h from the guide line 3 to the pickup coil 10 and a perpendicular line 11 of the guide line 3.
And the distance x from the pickup coil 10 to the vertical line 1
1 and the inclination α of the pickup coil 10, the distance r between the guide line 3 and the pickup coil 10 is r = (h ² + x ² ) ^1/2 The inclination α between the perpendicular 11 and the pickup coil 10 is α = tan ⁻¹ ( x / h) Assuming that the inclination between the pickup coil 10 and the road surface 2 is β, the inclination γ of the pickup coil 10 with respect to the guideline 3 is: γ = α−β The induced voltage of the one left and right pickup coil 10 is Is proportional to the angle of Guideline 3 and inversely proportional to the square of the distance r, the induced voltage V of the coil is V = a · cosγ × 1 / r ² (a is a proportional constant) V = a · cos ｛tan ⁻¹ (X / h) -β｝ × 1 / (h
² + x ² ).

That is, this induced voltage is determined by Guideline 3
As the distance from the vehicle increases, the intensity decreases rapidly in inverse proportion to the square of the distance. The sum and difference of the induced voltages are shown in the graph of FIG. Note that, similarly to FIG. 8, the horizontal axis represents the left and right displacement of the automatic guided vehicle 1, and the vertical axis represents the induced voltage.

The voltage curve d represents the left and right pickup coils 1
The sum of the induced voltages 0 and 10 is shown, and the voltage curve c shows the difference between the induced voltages. As shown in the figure, the voltage curve d of the sum of the induced voltages has a mountain shape with a peak and is symmetrical with respect to the perpendicular 11 of the guideline 3 as a center line. The voltage curve c of the difference between the induced voltages is the origin on the perpendicular 11. A sinusoidal curve passing through.

According to the automatic guided vehicle guiding apparatus of the present invention, since the distance between the left and right pickup coils 10, 10 and the inclination angle with respect to each road surface 2 are set, the left and right pickup coils 10, 10 are set. When the center between them is positioned on the guideline 3, a peak-shaped voltage curve d is obtained in which the sum of the induced voltages of the two pickup coils 10 and 10 has a peak, and does not become concave at the top as in the conventional case. The threshold value for judging the presence or absence of the detection of the guideline 3 can be properly set, and it is easier to use for control than before, and it is possible to accurately detect whether the automatic guided vehicle 1 has deviated from the guideline 3 or not. Therefore, appropriate guidance such as runaway prevention can be performed.

[0017]

According to the present invention, the threshold value for judging the presence or absence of the guideline can be accurately determined from the sum of the induced voltages of the left and right pickup coils. , Accurately detects whether the automatic guided vehicle has deviated from the guideline, and can perform guidance by appropriate steering based on the amount of left and right deviation due to the difference in the induced voltage of the left and right pickup coils while preventing runaway Becomes

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of an automatic guided vehicle guidance device showing one embodiment of the present invention.

FIG. 2 is a plan view showing a relationship between an inclination angle and a distance of one pickup coil in the embodiment.

FIG. 3 is a graph showing the sum and difference of induced voltages by the automatic guided vehicle guidance apparatus of the embodiment.

FIG. 4 is a perspective view showing a conventional automatic guided vehicle.

FIG. 5 is a schematic configuration diagram showing a conventional automatic guided vehicle guidance device.

FIG. 6 shows the structure of a conventional pickup coil (a).
Is a side view, and (b) is a front view.

FIG. 7 is a circuit block diagram of a guidance sensor of a conventional automatic guided vehicle guidance device.

FIG. 8 is a graph showing the sum and difference of induced voltages by a conventional automatic guided vehicle guidance device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Automatic guided vehicle, 2 ... Road surface, 3 ... Guideline, 4 ... Magnetic field, 10 ... Pickup coil.

Claims (1)

(57) [Scope of request for utility model registration] 1. A guideline for generating a magnetic field on a course of a traveling road surface of an automatic guided vehicle is provided, and a pair of left and right pickup coils for generating an induced voltage by the magnetic field of the guideline are provided on the automatic guided vehicle. The left and right pickups are provided in an automatic guided vehicle guidance device for steering and controlling the automatic guided vehicle along a course while detecting the amount of left and right deviation from the guide line of the automatic guided vehicle based on the sum and difference of mutual induced voltages. The distance between the left and right pickup coils and the inclination angle with respect to each road surface are set such that a peak-shaped voltage curve is obtained where the sum of the induced voltages of the two pickup coils is peaked when the center between the coils is positioned on the guide line. An automatic guided vehicle guidance device characterized by setting: