JP2007022282A - Estimation method of wheel wear amount of automated guided vehicle, determination method of wheel exchange time and traveling control method of automated guided vehicle and its device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method which controls the traveling state by appropriately grasping the wear of a wheel of an automated guided vehicle, and properly determines the exchanging time of the wheel. <P>SOLUTION: A measuring section of a predetermined distance is provided in a straight section of the path of the automated guided vehicle 10. The operation to measure the number of revolutions of a wheel 12 by an encoder 14 when the automated guided vehicle 10 travels in the measuring section at a constant speed is repeated until the automated guided vehicle 10 passes through the measuring section N times. An average value P of the number of pulses Pi measured for each time is calculated, and the actual distance which the wheel 12 advances per unit pulse is calculated from the average value P and the actual distance Y of the measuring section. When this X becomes not larger than the exchange time distance Z per unit pulse which is obtained from a wheel diameter Rc of a predetermined exchange time and the average value P, it is determined that it is the wheel exchange time. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a traveling control method and an apparatus for an automated guided vehicle for transporting articles, and more particularly, to a method for estimating an abrasion state of a wheel and correcting an error in a traveling distance of the automated guided vehicle due to wear. .

Conventionally, when transporting / transferring a semi-finished product such as a raw tire or a product such as a vulcanized tire, automatic traveling devices 51 and 51 as shown in FIGS. 5A and 5B are provided, for example. Many automated guided vehicles 50 are used. The automatic guided vehicle 50 includes a rectangular box-shaped casing 53 provided with bar members 52 and 52 on the upper surface for supporting a load that is lifted or lowered by a lift mechanism (not shown) or a carriage on which the load is mounted. , 51, while the reflective tape 55 affixed on the travel line 54 provided on the floor surface is detected by line detection sensors 56 a, 56 b such as photoelectric sensors provided on the left and right of the front surface of the casing 53. 54. Generally, the detection results of the line detection sensors 56a and 56b and the encoders (not shown) attached to the drive shafts of the left and right wheels 58a and 58b that are driven to rotate by the drive motors 57 and 57 are used. Based on the wheel speed calculated from the output, the rotational speed of the wheels 58a and 58b is controlled. At this time, the left and right wheels 56a and 56b are independently driven, and the rotational speeds of the left and right wheels 56a and 56b are respectively adjusted, so that the automatic guided vehicle 50 can be kept stable even in a curved traveling line. Can be caused to travel (see, for example, Patent Document 1).
When stopping the automatic guided vehicle, a stop marker provided separately on both sides of the travel line is detected, and the output of the encoder is counted to accumulate the travel distance of the automatic guided vehicle. If the vehicle is decelerated to a predetermined speed and then stopped after detecting the stop marker and then running for a predetermined distance, the automatic guided vehicle can be accurately stopped at the stop position ( For example, see Patent Document 2).
JP-A-10-63337 JP 2000-10632 A

By the way, the control of the traveling speed of the automatic guided vehicle is usually performed based on the rotational speed of the wheel. However, since the wheel diameter becomes smaller than the diameter when the wheel is worn, Since the travel distance becomes shorter than the travel distance calculated from the rotational speed of the wheels, troubles such as the stop position deviating from the initial position have occurred.
Therefore, when the diameter of the automated guided vehicle is measured during regular inspections, the worn wheels are replaced, or when the accumulated value of the travel distance exceeds a predetermined value, the wheels are worn. It is also possible to replace the wheel as, but it is not efficient to check all the conditions of the wheel of the automatic guided vehicle, and if the wheel is replaced based on the integrated value of the travel distance, If the replacement time is not estimated early, it is difficult to eliminate the deviation of the stop position.
In addition, when the deviation of the stop position exceeds the allowable range, it is conceivable to replace the wheel because the wheel is worn, but in this case as well, the wheel is replaced early, which increases the cost. There is a problem that becomes.

  The present invention has been made in view of the conventional problems, and provides a method for appropriately grasping the amount of wear of the wheel of the automatic guided vehicle and controlling its running state and appropriately determining the replacement time of the wheel. The purpose is to do.

As a result of intensive studies, the present inventors have detected the number of rotations of the wheel when the automatic guided vehicle is traveling in a predetermined straight section, and the wheel diameter is the diameter at the time of attachment (initial value). As a result, the present inventors have found that the amount of wheel wear can be estimated with high accuracy by comparing the calculated travel distance with the actual travel distance.
That is, the invention according to claim 1 of the present application detects the number of rotations of a wheel of the automated guided vehicle in a predetermined straight section, and detects the actual distance of the straight section and the detected wheel rotation. The amount of wear of the wheel is estimated using the calculated distance and the distance calculated from the initial value of the wheel diameter.
According to a second aspect of the present invention, in the method for estimating the wheel wear state of the automatic guided vehicle according to the first aspect, the traveling speed of the automatic guided vehicle in the straight section is a constant speed.

The invention according to claim 3 is a method for determining the replacement time of the wheel of the automatic guided vehicle, wherein the number of rotations of the wheel of the automatic guided vehicle in a predetermined straight section is detected, The wear amount of the wheel is estimated using the actual distance of the straight section, the travel distance calculation value calculated from the detected wheel rotation speed and the initial value of the wheel diameter, and the wear amount. When the estimated value exceeds a preset threshold value, it is determined that the wheel has reached the replacement time.
According to a fourth aspect of the present invention, in the wheel replacement timing determination method for the automatic guided vehicle according to the third aspect, in place of the estimated value of the wear amount, the rotational speed of the wheel in the straight traveling section and the straight traveling section The difference between the travel distance per unit angle calculated from the actual distance and the travel distance per unit angle calculated using the initial value of the wheel diameter is obtained, and the difference is set to a preset threshold value. When it exceeds, it determines with the said wheel having reached the replacement time, It is characterized by the above-mentioned.
According to a fifth aspect of the present invention, in the method for determining the wheel replacement timing of the automatic guided vehicle according to the third or fourth aspect, the estimated value of the wear amount or the difference in the travel distance per unit angle is preset. If the detected wheel diameter is exceeded, the wheel diameter is optically detected, and if the detected wheel diameter is less than the preset wheel diameter, it is determined that the wheel has reached the replacement time. It is characterized by.

The invention according to claim 6 is a method for controlling the traveling state of the automatic guided vehicle, wherein the number of revolutions of a wheel of the automatic guided vehicle in the traveling is detected in a predetermined straight traveling section, and the actual traveling section is actually detected. And the estimated amount of wear of the wheel, and the estimated amount of wear. Based on the wheel rotation speed of the automatic guided vehicle or the total number of rotations of the wheel on the predetermined route of the guided vehicle, or the both, the conveyance that decreases with the wear of the wheel. The present invention is characterized in that the travel distance of the car is corrected.
According to a seventh aspect of the present invention, in the traveling control method for the automatic guided vehicle according to the sixth aspect, in place of the estimated value of the wear amount, the rotational speed of the wheel in the straight section and the actual distance in the straight section. The difference between the travel distance per unit angle calculated from the above and the travel distance per unit angle calculated using the initial value of the wheel diameter is obtained, and the unmanned conveyance is performed based on the difference from the travel distance. One or both of the wheel rotation speed of the vehicle and the total number of rotations of the wheel along a predetermined route of the transport vehicle are changed.
The invention described in claim 8 is a travel control device for an automatic guided vehicle that controls a traveling state of the automatic guided vehicle by controlling a rotation speed of a wheel of the automatic guided vehicle.
Means for detecting the rotational speed of the wheel attached to the wheel of the automatic guided vehicle;
Means for detecting an entry time when the automated guided vehicle enters a predetermined straight section and a passing time after passing through the straight section;
Travel distance calculating means for calculating the calculated value of the travel distance of the wheel from the rotation speed of the wheel in the straight section, the initial value of the diameter of the wheel, and the time interval from the entry time to the passing time; ,
Based on the difference between the calculated value of the travel distance and the actual distance of the straight section, either the rotational speed of the wheel or the total rotational speed of the wheel on a predetermined route of the carrier vehicle, or both And means for changing,
The travel distance of the transport vehicle that decreases with the wear of the wheels is corrected so that the automatic guided vehicle can be accurately moved to a predetermined position set in advance.

According to the present invention, the rotational speed of a wheel in a predetermined straight traveling section of a traveling automatic guided vehicle is detected, and the actual distance of the straight traveling section, the detected wheel rotational speed, and the initial diameter of the wheel are detected. Since the wear amount of the wheel is estimated using the calculated value calculated using and, the wear state of the wheel can be accurately detected. In addition, the estimated wear amount or a distance corresponding to the estimated wear amount, the travel distance per unit angle calculated from the rotational speed of the wheel in the straight section and the actual distance in the straight section, and the wheel Based on the difference from the travel distance per unit angle calculated using the initial value of the diameter of the wheel, the wheel rotation speed of the automatic guided vehicle or the total number of rotations of the wheel in a predetermined route of the transport vehicle is calculated. Since the change is made, it is possible to eliminate the error in the travel distance of the automatic guided vehicle, and it is possible to perform the travel control with the same accuracy as when the wheels are attached.
Further, when a threshold is provided for the difference between the wear amount or the travel distance per unit angle, and the difference between the estimated wear amount or the travel distance exceeds the threshold, the wheel is replaced. If it is determined that it has reached, the wheel can be replaced at an appropriate time.
If the wheel diameter is optically detected and the detected wheel diameter is less than a preset wheel diameter, it is determined that the wheel has reached the replacement time. The certainty of time can be further improved.

Hereinafter, the best mode of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram showing a method for estimating the wheel wear state of an automated guided vehicle according to the best mode, and FIG. 2 is a diagram showing details of a control controller of the automated guided vehicle 10 according to the present invention. In each figure, reference numeral 10 denotes the guide path 20 while detecting a marker 21 such as a reflective tape affixed on the guide path 20 of the automatic guided vehicle by left and right marker detection sensors 11 and 11 attached to the front of the vehicle body. The automatic guided vehicle 30 that travels along the line 30 monitors the traveling state of the automatic guided vehicle 10 based on a preset control program signal, and positions of the automatic guided vehicle 10 and other automatic guided vehicles (not shown). It is a host controller that monitors the running state of a large number of automatic guided vehicles such as the traveling speed.
The automatic guided vehicle 10 includes a wheel 12, a motor 13 that drives the wheel 12, an encoder 14 that detects the number of rotations of the wheel 12, a light emitting element 15a, and a light receiving element 15b. A wheel diameter detection sensor 15 for detecting, a trigger detection means 16 for detecting a measurement start trigger and a measurement end trigger for instructing a measurement start and a measurement end of wheel rotation number measurement performed to estimate a wheel wear state to be described later; And a controller 17 for controlling the start / run / stop of the automatic guided vehicle 10 by driving / controlling the motor 13. In this example, the controller 17 controls the rotation speed of the motor 13. The travel distance of the automatic guided vehicle 10 is calculated from the output of the encoder 14 and the traveling control means 17a that controls the traveling speed of the automatic guided vehicle 10 to control. In addition to the travel distance calculation means 17b, a wheel wear state estimation means 17c that calculates a travel distance per unit pulse that is a measure of the wear amount of the wheel 12 and estimates the wear state of the wheel 12, and a preset wheel Wheel replacement time determination means 17d for storing a set value such as a replacement guide distance W that is a guide for replacement and a distance Z traveled by the wheel 12 per unit pulse worth the wheel replacement, and for determining the replacement time of the wheel 12 is provided. ing.
Reference numerals 40a and 40b denote position detection means provided at a predetermined distance in the straight section of the wheel 12 of the automatic guided vehicle 10, and the position detection means 40a is configured so that the leading position of the automatic guided vehicle 10 is in the straight section. When the vehicle enters the vehicle, the position detection means 40b detects when the leading position of the automatic guided vehicle 10 has passed through the straight section, and starts or measures the measurement of the wheel rotational speed for estimating the wheel wear state. An end trigger is generated, and this trigger is transmitted to the trigger detection means 16 of the automatic guided vehicle 10. As such position detection means 40a, 40b, for example, an apparatus provided with an optical sensor composed of a light emitting element and a light receiving element and a trigger generating means can be used. Specifically, when the position detection bar 18 provided on the front side surface of the automatic guided vehicle 10 passes between the light emitting element and the light receiving element of the optical sensor, the trigger generating means starts measurement or performs measurement. An end trigger may be generated and transmitted to the automatic guided vehicle 10 so as to notify the automatic guided vehicle 10 that the measurement start position has been reached or that the vehicle has traveled to the measurement end position.

Next, a method for estimating the amount of wheel wear according to the present invention will be described with reference to the flowchart of FIG.
Here, it is assumed that the route of the automatic guided vehicle 10 has a straight traveling section as shown in FIG. 1 and a route that travels in the straight traveling section at a constant speed. In this example, a measurement section of a predetermined distance is provided in the straight traveling section, and an average value of the encoder output when the measurement section is passed N = 20 times is calculated and becomes a reference for the wear amount of the wheel 12 Calculate the mileage per pulse. In addition, the said measurement area is an area between the said position detection means 40a and the position detection means 40b in FIG.
First, a measurement counter for measuring the number of passes is reset to i = 0 in advance (step S10), and it is determined whether the automatic guided vehicle 10 has entered the measurement section. Specifically, it is determined whether or not the trigger detection means 16 has detected a measurement start trigger from the position detection means 40a (step S11). When the trigger detection means 16 detects the measurement start trigger, the controller 17 starts measuring the number of pulses detected by the encoder 14 (step S12). Thereby, the pulse number proportional to the rotation speed of the wheel 12 is detected.
The controller 17 continues the measurement of the number of pulses of the output pulse train until the trigger detection unit 16 detects the measurement end trigger from the position detection unit 40b, and the automatic guided vehicle 10 travels in the measurement section. The number of pulses during measurement is measured (step S13). At this time, the interval between the pulse trains is examined to determine whether the automatic guided vehicle 10 is traveling at a constant speed (step S14). If it is confirmed that the speed is constant, the process proceeds to step S15. After storing the measured pulse number P _i , the measurement counter is advanced by one (step S16). If the speed of the automatic guided vehicle 10 does not become constant due to the occurrence of slipping on the wheels 12, it is assumed that the number of pulses has not been measured and is not added to the number of measurements.
Then, the automatic guided vehicle 10 is the measurement interval so as to pass through N = 20 times, repeated until the step S11~ step S16, sequentially storing measured pulse number P _i for each count (step S17).
When N = 20 measurements are completed, the average value P of the number of pulses P _i is calculated (step S18). Assuming that the actual distance of the upper measurement section is Y, a value X = Y / P obtained by dividing the distance Y by the average value P of the number of pulses represents the distance traveled by the wheel 12 per unit pulse. In this example, the amount of wear of the wheel 12 is not directly calculated, but the distance X = Y / P per unit pulse, which is a measure of the amount of wear of the wheel 12, is calculated (step S19).
By the way, when the wear amount of the wheel is x, the radius when the wheel is mounted is R0, and the number of pulses output by the encoder 14 by one rotation of the wheel is n, the wheel 12 rotates (P / n). Y is obtained by Y = 2π (R0−x) · (P / n). Therefore, as shown in FIG. 3, if step S20 for estimating the wheel wear amount x from the value of X is provided after step S19 for calculating X, the wheel wear amount x itself is also estimated. Can do.

Next, a method of correcting the error of the travel distance accompanying the wheel replacement time and the wheel wear will be described based on the flowchart of FIG.
First, the wheel exchanging time determination means 17d compares the cumulative travel distance V of the automatic guided vehicle 10 with the exchanging guide distance W that serves as a guide for exchanging the wheels (step S1). Information is notified to the host controller 30 (step S7), and the wheel 12 of the automatic guided vehicle 10 is exchanged.
If V <W in step S1, the process proceeds to step 2 to estimate the wear amount x of the wheel 12. The estimation of the wear amount x is performed according to the flowchart of FIG. 2 described above. The difference between the distance X per unit pulse and the reference distance X0 per unit pulse calculated from the initial value R0 of the wheel diameter and the average value P of the number of pulses calculated as the wheel 12 is not worn. Since Δ = X0−X is proportional to the wheel wear amount x, in this example, calculation of the wheel wear amount x is omitted, and the distance X per unit pulse and the wheel diameter at a preset replacement time are omitted. The wheel replacement time is determined by comparing the replacement time distance Z, which is a distance per unit pulse, obtained from Rc and the average value P of the number of pulses (step S3).
If X ≦ Z in step S3, that is, if the calculated distance X per unit pulse is less than or equal to the replacement timing distance Z, the process proceeds to step S4, and the wheel diameter detection sensor 15 is used to The diameter of 12 is detected (step S4). Specifically, as shown in FIG. 2, the light-emitting element 15 a and the light-receiving element 15 b of the wheel diameter detection sensor 15 are installed facing the front and rear of the wheel 12. At this time, when the wear of the light emitting element 15a and the light receiving element 15b is small, the light from the light emitting element 15a is blocked by the wheel 12 and does not enter the light receiving element 15b. When the diameter is reduced and the wheel 12 is worn down to the wheel diameter Rc that serves as a guide for replacement, it is installed at a position where the light from the light emitting element 15a enters the light receiving element 15b. If the light emitting element 15a and the light receiving element 15b are thus installed, light enters the light receiving element 15b when the wheel 12 is worn down to the wheel diameter Rc. Therefore, if an output from the light receiving element 15b such as a current flowing through the light receiving element 15b is detected, it is detected that the wheel has been worn to a predetermined diameter. It can be detected that the diameter Rc has been reached.

Therefore, in step S5, when there is an output from the light receiving element 15b, it is determined that the wheel 12 needs to be replaced, and this information is notified to the host controller 30 (step S6). If there is no output from the light receiving element 15b, the process returns to step S2, and the calculation of the distance X per unit pulse of the wheel 12 in the measurement section is continued.
On the other hand, if X> Z in step S3, it is determined that the wheel replacement time has not been reached, and the process proceeds to step S7 to determine whether to increase the wheel rotation speed. In other words, the diameter of the wheel 12 is not worn enough to be replaced, but the actual distance X traveled by the wheel 12 per unit pulse is the distance X0 traveled per unit pulse in a state where the wheel in the initial state is just attached. Shorter than. Therefore, for example, a plurality of set values X _k (where X _k <X _k-1 <X0) are set, and when X ₁ ≦ X <X0, it is determined that wear has not progressed, and no instruction is given to increase the wheel speed. Returning to step S2, the measurement of the amount of wear of the wheel 12 is continued. On the other hand, in the case of X <X ₁ , in order to eliminate the error between the distance X0 and the distance X, the process proceeds to step S8 to increase the rotational speed of the motor 13 to increase the rotational speed of the wheel 12, thereby The travel speed of the vehicle 10 is instructed to be the speed when the wheels 12 are not worn, and the process returns to step S2 to continue measuring the amount of wear of the wheels 12, that is, calculating the distance X per unit pulse. To do. In the k-th measurement, if X <X _k , the rotational speed of the motor 13 is increased and the rotational speed of the wheel is increased by n _k times. Since it is possible to return to the speed when the wheel 12 is not worn, it is possible to reliably eliminate the error in the travel distance due to the wear of the wheel 12.

Thus, according to this best mode, when the measurement section of a predetermined distance is provided in the straight section of the route of the automatic guided vehicle 10 and the automatic guided vehicle 10 travels in the measurement section at a constant speed. The operation of measuring the number of rotations of the wheels 12 with the encoder 14 is repeated until the automatic guided vehicle 10 passes through the measurement section N times, and the number of pulses P _i measured each time is stored. calculates an average value P of the P _i, calculate the actual distance above measurement interval by using the average value P of Y and the number of pulses, the actual distance X = Y / P of travel of the wheels 12 per unit pulse If this X is less than the replacement time distance Z per unit pulse obtained from the wheel diameter Rc of the preset replacement time and the average value P of the number of pulses, it is determined that it is the wheel replacement time. , X> Z, this X Since the number of revolutions of the wheel 12 is increased based on the difference between the distance X0 traveled per unit pulse with the wheel 12 just attached, the replacement time of the wheel 12 can be reliably determined. At the same time, an error in the travel distance due to wear of the wheels 12 can be reliably eliminated.

In the above-described best mode, the automatic guided vehicle 10 that moves along the guide path 20 affixed to the floor has been described. However, the present invention is not limited to this, and a rail provided on a wall surface or a ceiling. The present invention can also be applied to other forms of automatic guided vehicles such as a type of automatic guided vehicle that travels above.
In the above example, the rotational speed of the wheel 12 is increased to eliminate the error in the travel distance due to the wear of the wheel 12, but the travel distance of the automatic guided vehicle 10 depends on the diameter of the wheel 12 and the total number of rotations. Therefore, the total rotational speed of the wheels 12 when traveling on the route of the automatic guided vehicle 10 may be increased while the rotational speed of the wheels 12 is left as it is. That is, since the number of pulses detected by the encoder 14 indicates the travel distance of the automatic guided vehicle 10, the total number of pulses from the start of travel to the stop of travel of the automatic guided vehicle 10 set at the beginning is calculated per unit pulse. If it is changed so as to increase according to the distance X, the error in the travel distance due to wear of the wheels 12 can be eliminated. Since errors due to wear of the wheels 12 are small, it is sufficient to change the wheel rotation speed and the total number of pulses not only on the reciprocating path of the automatic guided vehicle 10 but only on the path of constant speed operation. The mileage error can be adjusted.

In the above example, the rotational speed of the wheel 12 is detected by using the pulse encoder 14, but as a method of detecting the rotational speed of the wheel 12, a multipolar magnet is attached to the drive shaft and this is used as a magnetoresistive element. A well-known wheel speed sensor such as a type that detects the above may be used.
In the above example, the automatic guided vehicle 10 passes through the straight section 20 times to calculate the distance X per unit pulse of the wheel 12 or the wear amount x. However, the number of times of measurement is not limited to this. This is appropriately determined depending on the traveling speed of the transport vehicle 10, the weight of the load to be loaded, the diameter of the wheel 12, or the like.
Note that when calculating the distance X per unit pulse of the wheel 12 or the wear amount x, the speed of the automatic guided vehicle 10 does not necessarily have to be a constant speed, and there may be a section in which acceleration / deceleration occurs. In order to accurately estimate the distance X or the wear amount x, it is preferable to perform the estimation at a constant speed and in a straight line as in this example.

In the above example, the position detection means 40 a and 40 b provided with optical sensors are provided on the side surface side of the traveling path of the automatic guided vehicle 10, and the position detection bar 18 provided on the side surface side of the automatic guided vehicle 10 is provided. A trigger for starting or stopping measurement is sent to the controller 17 of the automatic guided vehicle 10 when the optical sensor is passed, but a bar corresponding to the position detection bar 18 is provided on the side of the traveling path. The position detection means 40a and 40b provided with optical sensors may be provided on the side surface side of the automatic guided vehicle 10.
As the position detection means, in addition to the combination of the optical sensor and the passing bar, a combination of a magnetic sensor and a marker made of metal or a magnetic material, a combination of a distance sensor and a reflector, or a tag reader and an ID Other means such as a combination of tags may be used.
In the above example, by detecting whether or not the diameter of the wheel 12 has been worn down to a predetermined diameter using a set of light emitting elements and light receiving elements, it is determined whether or not the wheel diameter has fallen below a preset threshold value. Although it has been determined, a distance sensor may be installed against the rotation surface of the wheel 12, and the distance between the wheel 12 and the distance sensor may be measured to obtain the wheel diameter.
Note that the measurement of the wheel diameter is not necessarily an essential matter. Therefore, when the measurement of the wheel diameter is omitted and the distance X per unit pulse is equal to or less than the replacement time distance Z, or the wear amount x exceeds the predetermined amount. The wheels 12 may be replaced immediately.

As described above, according to the present invention, since it is possible to appropriately determine the replacement time of the wheels without measuring all the diameters of the automatic guided vehicle, maintenance of the automatic guided vehicle is facilitated, and maintenance work is performed. Efficiency can be improved.
In addition, since it is possible to eliminate the error in the mileage due to wheel wear, it is possible to prevent troubles such as the stop position from deviating from the original position, and the same accuracy as when the wheel is mounted. High traveling control can be performed.

It is a figure which shows the estimation method of the wheel abrasion state of the automatic guided vehicle which concerns on the best form of this invention. It is a figure which shows the detail of the control controller of the automatic guided vehicle by this invention. It is a figure which shows the flowchart for estimating the amount of wheel wear. It is a figure which shows the flowchart for performing the error correction of the determination of wheel replacement | exchange time, and the mileage by wear of a wheel. It is a figure which shows the structure of the conventional automatic guided vehicle.

Explanation of symbols

10 automatic guided vehicle, 11 marker detection sensor, 12 wheels, 13 motor,
14 Encoder, 15 Wheel diameter detection sensor, 15a Light emitting element, 15b Light receiving element,
16 trigger detection means, 17 control controller, 17a travel control means,
17b Travel distance calculation means, 17c Wheel wear state estimation means,
17d Wheel replacement time determination means, 18 position detection bar, 20 guideway, 21 marker, 30 host controller, 40a, 40b position detection means.

Claims (8)

  The number of revolutions of a traveling automatic guided vehicle wheel within a predetermined straight section is detected and calculated from the actual distance of the straight section, the detected wheel speed and the initial value of the wheel diameter. A method for estimating a wheel wear amount of an automated guided vehicle, wherein the wear amount of the wheel is estimated using a calculated travel distance.   The method for estimating a wheel wear state of an automatic guided vehicle according to claim 1, wherein a traveling speed of the automatic guided vehicle in the straight section is set to a constant speed.   The number of revolutions of a traveling automatic guided vehicle wheel within a predetermined straight section is detected and calculated from the actual distance of the straight section, the detected wheel speed and the initial value of the wheel diameter. Using the calculated travel distance, the wear amount of the wheel is estimated, and when the estimated value of the wear amount exceeds a preset threshold, it is determined that the wheel has reached the replacement time. A method for determining the wheel replacement time of a guided automatic guided vehicle.   Instead of the estimated amount of wear, using the travel distance per unit angle calculated from the rotation speed of the wheel in the straight section and the actual distance of the straight section, and the initial value of the diameter of the wheel The difference between the calculated travel distance per unit angle is obtained, and when the difference exceeds a preset threshold, it is determined that the wheel has reached the replacement time. Judgment method of wheel replacement time of automatic guided vehicle.   When the estimated value of the wear amount or the difference in travel distance per unit angle exceeds a preset threshold, the wheel diameter is optically detected, and the detected wheel diameter is a preset wheel. 5. The method for determining the wheel replacement time of an automatic guided vehicle according to claim 3 or 4, wherein the wheel is determined to have reached the replacement time when the diameter is not reached.   The number of revolutions of a traveling automatic guided vehicle wheel within a predetermined straight section is detected and calculated from the actual distance of the straight section, the detected wheel speed and the initial value of the wheel diameter. The estimated amount of wear of the wheel is estimated using the calculated travel distance, and the wheel rotation speed of the automatic guided vehicle based on the estimated amount of wear and the wheel on the predetermined route of the transport vehicle. Any one or both of the total rotational speeds of the automatic guided vehicle are changed.   Instead of the estimated value of the amount of wear, the calculation is performed using the travel distance per unit angle calculated from the rotation speed of the wheel in the straight section and the actual distance in the straight section, and the initial value of the wheel diameter. The difference in the travel distance per unit angle is calculated, and the wheel rotation speed of the automatic guided vehicle based on the difference in travel distance per unit angle, or the total rotation of the wheel in a predetermined route of the transport vehicle. The traveling control method for an automatic guided vehicle according to claim 6, wherein either one or both of the numbers are changed. Means for detecting the rotational speed of the wheel attached to the wheel of the automatic guided vehicle;
Means for detecting an entry time when the automated guided vehicle enters a predetermined straight section and a passing time after passing through the straight section;
Travel distance calculating means for calculating the calculated value of the travel distance of the wheel from the rotation speed of the wheel in the straight section, the initial value of the diameter of the wheel, and the time interval from the entry time to the passing time; ,
Based on the difference between the calculated value of the travel distance and the actual distance of the straight section, either the rotational speed of the wheel or the total rotational speed of the wheel on a predetermined route of the carrier vehicle, or both Means to change,
A travel control device for an automated guided vehicle.

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