JPS6112567B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Application of the Invention] The present invention relates to an automatic steering method for a mobile body, particularly a mobile body suitable for automatically steering a crane that runs on tires along a laid guide line.

[Background of the invention]

Tire-driven container cranes are used to transport containers within container yards. This type of crane has the disadvantage of being inferior in straight running performance compared to rail traveling cranes. In order to compensate for this drawback, an automatic steering system is provided in which a guide line for straight travel is buried underground and the crane runs along the guide line. This steering control detects the deviation from the guide line and gives a signal to the crane's traveling device to correct the traveling speed of each leg of the crane based on the detection result.

Conventionally, the correction signal given to the traveling device is obtained from the amount of deviation of the tire (or detector) from the guide line, the first derivative of the deviation amount, and the second derivative. If signals based on these differentials are introduced into the correction signal, the crane will not steer during correction and will smoothly return to the guide line within the specified range.

However, the conventional steering correction method utilizes the first or second derivative of the amount of deviation as a correction signal, so it is significantly affected by signal ripple and nozzles, making it difficult to obtain stable steering performance. .

[Purpose of the invention]

An object of the present invention is to stabilize steering performance and improve smoothness.

[Summary of the invention]

The present invention is an automatic steering method for driving a moving object along a planned travel route, and includes a first method for inputting the speed of the moving object and reducing the output when the speed is high and increasing the output when the speed is low. A second signal is generated by multiplying a signal whose speed is corrected by a bias signal by the amount of deviation of the moving object, and dead band processing is performed on the second signal, so that the second signal is The second signal is output only when the value exceeds a certain value, and a signal obtained by multiplying the first signal and the second signal after dead band processing is used for automatic steering.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

In this embodiment, for example, when the traveling speed is slow,
The correction amount is increased, but the correction start point is (dead
(band) is wide, and if the running speed is fast, the correction amount is small, but the correction start point is (dead band)
) By narrowing the width, a smooth automatic steering correction function is obtained, and the specific details are as follows.

FIG. 1 shows a tire-driven crane. Although the trolley part is omitted, the crane structure 1 is 4
The vehicle has wheels made of rubber tires, of which driving wheels 2, 3 and driven wheels 4, 5 driven by an electric motor are provided at diagonal corners of each other. A guide wire 6 is buried underground in the running direction to guide straight travel, and from this guide wire 6,
It induces an induced magnetic field. 2 on the crane running legs
Antenna box 7 housing a pair of signal receiving antennas
There is.

Figure 2 shows a DC motor 8 that drives the driving wheels 2 and 3.
and 9, and speed control devices 12 and 1 including finger speed generators 10 and 11 for controlling them.
3 is shown. Although the armature voltage control method is shown in FIG. 2, other speed control methods, such as a motor field control method, may be used.

FIG. 3 shows the planar positions of the guide wire 6 and the two pairs of antennas 14 and 15. The outputs of the two pairs of antennas generated by receiving the magnetic field from the guide wire 6 are input to the phase discriminator amplifier 16, and the outputs of the antenna 14 as shown in FIG.
Output characteristics 17 of the antenna 15 and output characteristics 1 of the antenna 15
8 is the output characteristic 1 in Figure 5 based on the relationship between magnitude and phase.
It is converted into a characteristic like 9. In addition, Figures 4 and 5
In both figures, the vertical axis shows the voltage, the horizontal axis shows the deviation, and point A shows the position of the guide line 6.

In FIG. 6, the outputs of two pairs of antennas 14 and 15 and a phase discrimination amplifier 16 are input to a multiplier 20. On the other hand, the output of the finger speed generator 10, which is a traveling speed detector, is corrected by a bias signal, and then a multiplier 20
is inputted to and multiplied by the deviation output described above.
The bias signal is biased to provide constant correction because the steering force does not change much at low speeds below a certain constant speed. The output of multiplier 20 is a dead band zone.
zone) is input to another multiplier 22 via an amplifier 21. Here, the role of the dead band zone amplifier 21 is to determine the steering correction start position, which changes depending on the product of the deviation amount and speed. That is,
If the speed is slow, a correction signal will appear when the amount of deviation becomes large, and if the speed is fast, a correction signal will appear even if the amount of deviation is small.

On the other hand, the output of the finger speed generator 10 is input to a comparator 23, which determines whether it is high speed or low speed, and weights the output.
That is, when the speed is high, the output is small, and when the speed is low, the output is large, and is input to the multiplier 22 and multiplied by the input of the amplifier 21. This signal is given as a correction signal for the speed of each speed control system 24 and 25, thereby making it possible to obtain smooth automatic steering.

〔Effect of the invention〕

As described above, according to the present invention, the causes of susceptibility to signal ripple and noise are eliminated, and the amount of correction of the steering correction signal can be given to the speed control system as a function of the traveling speed, resulting in stable and smooth automatic steering. There are effects that can be achieved.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the main structure of a tire-driven crane, FIG. 2 is a schematic circuit diagram of a speed control device for a traveling drive device when the present invention is applied to the crane shown in FIG. 1, and FIG. The figure is a plan layout of the antenna and guide wire of a crane that adopts the present invention, Figure 4 is a diagram of the output characteristics of the antenna shown in Figure 3, and Figure 5 is after converting the output characteristics of Figure 4. The characteristic diagram, FIG. 6, is a correction signal generation block diagram according to the present invention. 2, 3... Driving wheel, 6... Guide wire, 7... Antenna box, 10, 11... Finger speed generator, 12, 13...
...Speed control device, 14, 15...Antenna, 2
0, 22...multiplier, 21...dead band zone
Amplifier, 23... comparator.

Claims (1)

[Claims] 1. A traveling device that causes a moving object to travel along a scheduled travel route, a detector that detects the amount of deviation when the moving object deviates from the planned travel route, and a detector that detects the speed of the mobile object. In the automatic steering method for a moving object, the speed is input and the speed is output when the speed is high. generates a first signal such that the output is large when the speed is small and low, and a second signal is generated by multiplying a signal obtained by correcting the speed by a bias signal and the deviation amount;
performing dead band processing on the second signal;
Only when the second signal exceeds a certain value, the second signal
An automatic steering method for a mobile object, comprising: outputting a signal, and performing automatic steering by using a signal obtained by multiplying the first signal and the second signal after deck band processing to control the traveling device. .