WO2020032358A1 - Procédé de détermination de position d'un véhicule guidé - Google Patents

Procédé de détermination de position d'un véhicule guidé Download PDF

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Publication number
WO2020032358A1
WO2020032358A1 PCT/KR2019/006299 KR2019006299W WO2020032358A1 WO 2020032358 A1 WO2020032358 A1 WO 2020032358A1 KR 2019006299 W KR2019006299 W KR 2019006299W WO 2020032358 A1 WO2020032358 A1 WO 2020032358A1
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WO
WIPO (PCT)
Prior art keywords
unit
encoder
position signal
reference sensor
signal
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Application number
PCT/KR2019/006299
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English (en)
Korean (ko)
Inventor
홍순호
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현대무벡스 주식회사
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Publication of WO2020032358A1 publication Critical patent/WO2020032358A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B61—RAILWAYS
    • B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L25/00—Recording or indicating positions or identities of vehicles or vehicle trains or setting of track apparatus
    • B61L25/02—Indicating or recording positions or identities of vehicles or vehicle trains
    • B61L25/026—Relative localisation, e.g. using odometer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B61—RAILWAYS
    • B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L25/00—Recording or indicating positions or identities of vehicles or vehicle trains or setting of track apparatus
    • B61L25/02—Indicating or recording positions or identities of vehicles or vehicle trains

Definitions

  • the present invention relates to a method of determining the position of the transfer bogie, and more specifically, to position the transfer bogie through the reference sensor unit by periodically correcting the position error of the encoder sensor unit through the reference sensor unit for detecting the sensing plates arranged at regular intervals on the rail.
  • the reference unit count of the reference sensor counter is increased or decreased, the number of encoder unit counts of the encoder sensor counter is initialized to accurately determine the feed cart position with low resolution through the reference sensor unit. It is also possible to determine the minute position change of the transfer cart between the sensing plate through the sensor unit.
  • robots are introduced and expanded robots are used in places that are difficult to work with, thereby reducing labor costs and increasing work efficiency and productivity.
  • the rail guided vehicle (RGV) of the unmanned transfer truck is controlled to transfer a predetermined load along a rail of a storage line or a storage line while the transport truck reciprocates on a straight or curved rail.
  • one or more transfer trucks are typically configured to perform a load transfer or load operation of a cargo while driving on a rail by receiving a destination from a main server. That is, in the RTV system, each transport truck is assigned a destination from the server and moves the cargo at the set speed along the rail to the assigned destination.
  • the feed bogie is equipped with an encoder sensor to measure the rotational information of the motor, which measures the movement distance or the movement speed of the transfer bogie moving along the rail, and the transfer bogie along the rail to the destination based on the measured movement distance or movement speed. Control the movement of the vehicle and detect the destination identification plate placed at the destination to stop the transfer truck to the destination.
  • Fast freight transfer in the RTV system is a key factor in reducing logistics costs, and it is necessary to drive the transport cart at high speed to the destination set for fast freight transfer.
  • the deceleration sensing plate is placed before the destination.
  • the transfer sensor detects the deceleration sensing plate at high speed before detecting the deceleration sensing plate. Control the movement of the feed cart at low speed by decelerating the speed.
  • the present invention is to solve the problems of the above-described position determination method of the transfer bogie, the object of the present invention is to provide an encoder sensor unit and the reference sensor unit for detecting the sensing plate disposed at regular intervals on the rail It is to provide a position determination device of the transport cart that can accurately compensate the position of the transport cart through the sensor unit.
  • Another object of the present invention is to provide a position determination apparatus for a transfer bogie which can determine a small position change of the transfer bogie through an encoder sensor unit while determining the transfer bogie position with a low resolution through a reference sensor unit.
  • Another object of the present invention is to provide an apparatus for determining the position of the conveying bogie, capable of high speed travel by accurately determining the position of the conveying bogie.
  • the position determination device of the transfer bogie is an encoder sensor for generating a first position signal and a second position signal having a phase of 90 degrees with respect to the first position signal in accordance with the rotation of the motor
  • a reference sensor unit configured to detect sensing plates arranged at regular intervals along the rail to generate a fourth position signal having a phase of 90 degrees with respect to the third position signal and the third position signal, and the first position signal and the first position signal.
  • a position compensator for compensating for the movement distance of the transport cart based on the second position signal based on the third position signal and the fourth position signal.
  • the position compensator comprises: an encoder sensor counter for counting the movement distance of the transport trolley according to the movement direction of the trolley based on the rising edge and the falling edge of the first position signal and the rising edge and the falling edge of the second position signal;
  • the reference unit counter of the reference sensor counter and the reference sensor counter that counts the movement distance of the feed cart according to the moving direction of the feed cart based on the rising edge and the falling edge of the three position signal and the rising edge and the falling edge of the fourth position signal
  • a compensation unit that compensates the number of encoder unit counts counted by the encoder sensor counter with a reference unit count each time an increase or decrease occurs.
  • the reference sensor unit includes a first reference sensor unit generating a third position signal and a second reference sensor unit generating a fourth position signal, wherein the first reference sensor unit and the second reference sensor unit count one reference unit. And n (n is a natural number) for each encoder unit.
  • the compensation unit may be configured to initialize the number of encoder unit counts counted by the encoder sensor counter whenever the reference unit count of the reference sensor counter increases or decreases.
  • the compensator may generate an error signal when the number of encoder unit counts is greater than or equal to a set value when the reference unit count of the reference sensor counter increases or decreases.
  • An apparatus for determining a position of a transport cart according to the present invention has various effects as follows.
  • the position determination device of the transfer truck by correcting the position error of the encoder sensor unit periodically through the reference sensor unit for detecting the sensing plates arranged at regular intervals on the rail, the position of the transport bogie accurately through the reference sensor unit You can compensate.
  • the position determination device of the transfer bogie initializes the number of encoder unit counts of the encoder sensor counter every time the reference unit count of the reference sensor counter increases or decreases, thereby transferring the transfer bogie position with a low resolution through the reference sensor unit. At the same time, it is possible to determine the precise position change of the transport cart between the sensing plates through the encoder sensor unit.
  • the position determination device of the transfer truck by accurately determining the position of the transport bogie through the encoder sensor unit and the separate reference sensor unit, it is possible to drive the transport bogie at high speed, thereby reducing the logistics cost.
  • FIG. 1 is a view for explaining a transport system using a transport cart according to an embodiment of the present invention.
  • FIG. 2 is a functional block diagram illustrating an apparatus for determining a position of a transport cart according to an embodiment of the present invention.
  • FIG. 3 is a functional block diagram illustrating a position compensator according to an embodiment of the present invention.
  • FIG. 4 shows an example of an A-phase signal and a B-phase signal output from the encoder sensor counter according to the present invention.
  • FIG. 5 illustrates an example of a first reference signal and a second reference signal output from the reference sensor counter according to the present invention.
  • FIG. 6 is a view for explaining an example of a sensing plate disposed on a rail and a reference sensor unit disposed on a transport cart in a transport system using a transport cart according to the present invention.
  • FIG. 7 illustrates an example of a reference sensor.
  • FIG. 8 is a view for explaining an example of a method for compensating for the position of the transport bogie when the transport bogie moves in the forward direction.
  • FIG. 9 is a view for explaining an example of a method for compensating the position of the transport bogie when the transport bogie moves in the backward direction.
  • FIG. 1 is a view for explaining a transport system using a transport cart according to an embodiment of the present invention.
  • a rail 10 for transporting products or parts according to the working conditions and conditions are arranged on the floor or in the air.
  • At least one conveyance trolley C1, C2 is arranged along the rail 10, with the transport trolleys C1, C2 selectively moving in the forward or reverse direction to convey the article.
  • the transport trolleys C1 and C2 move along the rails 10 so as not to collide with each other, and each transport trolley moves to the destination after loading the goods at the starting point.
  • Each transport trolley is provided with means for determining the travel distance of the transport trolleys in order to stop at the destination accurately after moving from the origin to the destination.
  • each conveyance bogie is provided with the means for determining the position of a conveyance bogie.
  • Each transfer truck must move at high speed from the starting point to the destination to reduce the time and cost of transporting the goods.However, the distance of the transfer truck or the current position of the transfer truck must be accurately determined from the starting point to the destination to the set position before the destination. After driving at high speed, you can stop at the destination precisely by reducing the speed of the transfer truck from the set position.
  • the moving distance of the conveying bogie is determined by measuring the rotational speed of the motor driving the conveying bogie, and the movement distance of the conveying bogie is accurately determined only by measuring the rotational speed of the motor due to the slip between the rail and the conveying bogie. Difficult to do Therefore, in the present invention, by measuring the rotational speed of the motor driving the feed cart to determine the moving distance of the feed cart based on the rotational speed per unit time, and additionally the sensing plate disposed at regular distance intervals along the rail to which the feed cart is moved ( By compensating for the movement distance of the transport trolley through a sensor for detecting the same, it is possible to accurately determine the current position of the transport trolley on the rail.
  • FIG. 2 is a functional block diagram illustrating an apparatus for determining a position of a transport cart according to an embodiment of the present invention.
  • the encoder sensor unit 110 detects the rotational speed of the rotating disk disposed on the rotating shaft of the motor for driving the feed cart, the encoder sensor unit 110 to the rotation of the rotating disk Accordingly, the A-phase and B-phase signals having different phases are generated.
  • the A-phase signal and the B-phase signal are generated by changing the high / low values periodically by different phases.
  • the reference sensor unit 130 generates a first sensor signal and a second sensor signal having different phases according to whether the sensing plate disposed at a predetermined distance interval on the rail to which the transport cart moves.
  • the reference sensor unit 130 generates a first sensor signal having a high / low value according to whether a sensing plate disposed at a predetermined distance interval on the rail is detected, and a predetermined distance interval on the rail.
  • a second reference sensor 133 which generates a second sensor signal having a high / low value according to whether the sensing plate disposed in the sensing plate is detected.
  • the A-phase signal and the B-phase signal generated by the encoder sensor unit 110 have a phase of 90 degrees to each other, and the first sensor signal and the second reference sensor unit 133 generated by the first reference sensor unit 131.
  • the second sensor signals generated at) have a phase of 90 degrees to each other.
  • the position compensator 150 increases or decreases the count of the encoder sensor counter based on the values of the A-phase signal and the B-phase signal depending on whether the transfer bogie moves in the forward direction or the backward direction, and the transfer bogie
  • the reference sensor counter value is incremented or decremented based on the values of the first sensor signal and the second sensor signal, depending on whether is moved in the forward direction or the backward direction.
  • the position compensator 150 calculates a moving distance of the transport cart based on the encoder sensor counter value, and the position compensator 150 calculates based on the encoder sensor counter value whenever the reference sensor counter value increases or decreases. The travel distance of the feed cart is compensated by the reference sensor count.
  • the position compensator 150 determines the position of the transport cart by measuring the movement distance of the transport cart with the value of the encoder counter of the encoder sensor when the transport cart is located between the sensing plates. The exact position of the transport trolley may be determined by compensating the movement distance of the transport trolley with the value of the reference sensor counter of the sensor unit.
  • the notification unit 170 generates an error signal and transmits the generated error signal to the set terminal when the number of encoder unit counts is greater than or equal to the set value when the reference unit count of the reference sensor counter increases or decreases.
  • the administrator can quickly check whether the transport balance is abnormal based on the received error signal.
  • FIG. 3 is a functional block diagram illustrating a position compensator according to an embodiment of the present invention.
  • the encoder sensor counter 151 has a relative relationship between the A-phase signal and the B-phase signal based on a change in the relative high / low values of the A-phase signal and the B-phase signal output from the encoder sensor unit.
  • the value changes to the high / low value that is, the number of encoder unit counts is increased or decreased based on the change of the rising and falling edges of the A-phase signal and the rising and falling edges of the B-phase signal. Count.
  • the reference sensor counter 153 is a first reference signal and the first reference signal based on the change in the relative high / low value between the first reference signal output from the first reference sensor and the second reference signal output from the second reference sensor 2
  • the relative value of the reference signal changes to a high / low value, i.e., increases the number of reference unit counts based on the change of the rising and falling edges of the first reference signal and the rising and falling edges of the second reference signal, or Decrease counts the reference sensor count.
  • the compensation unit 155 compensates the number of encoder unit counts counted by the encoder sensor counter 151 to the reference unit count whenever the reference unit count increases or decreases in the reference sensor counter 153.
  • the encoder unit count has a resolution of n (n is a natural number) times the reference unit count.
  • the encoder unit count has a distributing power of 1000 times the reference unit count.
  • the number of encoder unit counts is compensated by the reference unit count, and the number of encoder unit counts is initialized so that the relative high between the A-phase signal and the B-phase signal again occurs until the next reference unit count occurs.
  • Count the number of encoder unit counts based on the change in the / low value.
  • Figure 4 shows an example of the A-phase signal and B-phase signal output from the encoder sensor counter according to the present invention
  • Figure 4 (a) is the A-phase signal and B-phase signal generated when the feed cart moves in the forward direction
  • (b) shows the number of A-phase signal and B-phase signal and encoder sensor count generated when the transfer bogie moves in the backward direction
  • 4 (c) shows the transfer bogie forward. The number of A-phase signal, B-phase signal, and encoder sensor count generated when moving in the reverse direction and then in the reverse direction is shown.
  • FIG. 5 illustrates an example of a first reference signal and a second reference signal output from a reference sensor counter according to the present invention.
  • FIG. 5 (a) illustrates a first reference signal generated when the transport cart moves in a forward direction. The second reference signal and the reference sensor count number are shown, 4 (b) shows the first reference signal and the second reference signal and the reference sensor count number generated when the feed cart moves in the backward direction, and 4 (c) ) Shows the number of the first reference signal, the second reference signal, and the reference sensor count generated when the transport cart moves in the forward direction and then in the backward direction.
  • the moving direction of the conveying bogie may be determined according to the relative order of occurrence of the rising edge and the falling edge of the A phase signal and the B phase signal, but according to the field to which the present invention is applied. It may be provided with a separate means, which is within the scope of the present invention.
  • FIG. 6 is a view for explaining an example of a sensing plate disposed on a rail and a reference sensor unit disposed on a transport cart in a transport system using a transport cart according to the present invention.
  • the sensing plate 20 is periodically disposed along a rail at a predetermined distance, and the sensing plate 20 is periodically disposed every d of the sensing plate 20, and the width of the sensing plate 20 is d. It is characterized by being / 2.
  • first reference sensor 131 and the second reference sensor 133 are disposed to be spaced apart from each other by a d / 4 distance.
  • FIG. 7 illustrates an example of a reference sensor.
  • the first reference sensor 131 and the second reference sensor 133 may include a sensing plate (a) when a transport cart moves along a rail. 20, the first reference sensor 131 has a light receiving portion R and a light emitting portion L on the first and second surfaces facing each other, as shown in FIG. 7B. It is arranged to operate to receive light from the light receiving portion R on the second surface facing the light emitted from the light emitting portion L on the first surface.
  • the sensing plate 20 exists in the space between the first surface and the second surface
  • the first reference sensor 131 outputs a first reference signal having a low value and senses in the space between the first surface and the second surface.
  • the first reference sensor 131 outputs a first reference signal having a high value.
  • the second reference sensor 133 also operates in the same configuration as the first reference sensor 131, and a detailed description thereof will be omitted.
  • FIG. 8 is a view for explaining an example of a method for compensating for the position of the transport bogie when the transport bogie moves in the forward direction.
  • the reference unit count corresponds to 1000 encoder unit counts, and the number of encoder unit counts increases when the feed cart moves in the forward direction.
  • the number of encoder unit counts accumulated at the time of increasing the reference unit count should be 1000.
  • the accumulated number of encoder units at time t1 is less than 1000, which means that the transfer balance moves more than the accumulated number of encoder units, and the distance between the actual transfer balance and the distance determined by the accumulated number of encoder units.
  • An error has occurred and the accumulated count of encoder units at time t3 is greater than 1000, which means that the feed balance has moved less than the accumulated count of encoder units, which is determined by the movement distance of the actual feed balance and the accumulated count of encoder units. An error has occurred between the distances traveled.
  • the point of time when the reference unit count increases indicates the absolute movement distance of the conveyance bogie, and the movement of the conveyance bogie determined by the accumulated number of encoder unit counts at each time point of increase of the reference unit count. Compensate distance with reference unit count.
  • FIG. 9 is a view for explaining an example of a method for compensating the position of the transport bogie when the transport bogie moves in the backward direction.
  • the reference unit count corresponds to 1000 encoder unit counts, and the number of encoder unit counts decreases when the feed cart moves in the reverse direction.
  • the number of encoder unit counts accumulated at the time when the reference unit count decreases should be -1000.
  • the accumulated number of encoder unit counts at time t3 is greater than -1000, which means that the transfer balance moves less than the accumulated number of encoder units. An error occurred.
  • the time point at which the reference unit count decreases represents an absolute movement distance of the transport bogie, and the movement of the transfer bogie determined by the number of encoder unit counts accumulated every time the reference unit count decreases. Compensate distance with reference unit count.
  • the moving distance of the transfer bogie is determined by the encoder sensor unit between the sensing plates, and the current position of the transfer bogie can be accurately determined by compensating the movement distance of the transfer bogie determined by the encoder sensor unit when the sensing plate is detected by the reference sensor unit.
  • the transport cart can be driven at high speed and stopped at the correct destination.
  • the above-described embodiments of the present invention can be written as a program that can be executed in a computer, and can be implemented in a general-purpose digital computer that operates the program using a computer-readable recording medium.
  • the computer-readable recording medium may include a magnetic storage medium (eg, ROM, floppy disk, hard disk, etc.), an optical reading medium (eg, CD-ROM, DVD, etc.) and a carrier wave (eg, the Internet). Storage medium).
  • a magnetic storage medium eg, ROM, floppy disk, hard disk, etc.
  • an optical reading medium eg, CD-ROM, DVD, etc.
  • a carrier wave eg, the Internet.

Abstract

La présente invention concerne un procédé de détermination d'une position d'un véhicule guidé et, plus précisément, un procédé de détermination d'une position d'un véhicule guidé, le procédé étant apte : à corriger périodiquement une erreur de position d'une unité capteur codeur par l'intermédiaire d'une unité capteur de référence destinée à détecter des plaques de détection agencées à intervalles prédéfinis le long de rails, et ainsi, à compenser précisément une position d'un véhicule guidé par l'intermédiaire de l'unité capteur de référence ; et à initialiser un nombre compté en tant que compte d'unité codeur par un compteur de capteur codeur chaque fois qu'un compte d'unité de référence d'un compteur de capteur de référence augmente ou diminue, de manière à déterminer avec précision une position d'un véhicule guidé en utilisant une faible résolution par l'intermédiaire de l'unité capteur de référence et à déterminer simultanément ne serait-ce qu'un léger changement de position du véhicule guidé entre les plaques de détection par l'intermédiaire de l'unité capteur codeur.
PCT/KR2019/006299 2018-08-07 2019-05-27 Procédé de détermination de position d'un véhicule guidé WO2020032358A1 (fr)

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KR10-2018-0091781 2018-08-07
KR1020180091781A KR102141807B1 (ko) 2018-08-07 2018-08-07 이송 대차의 위치 판단 방법

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KR102544564B1 (ko) * 2021-06-17 2023-06-20 현대무벡스 주식회사 소터의 캐리어 위치 검출 시스템
KR102544565B1 (ko) * 2021-06-17 2023-06-20 현대무벡스 주식회사 소터의 캐리어 위치 검출 시스템
KR20230109906A (ko) 2022-01-14 2023-07-21 현대무벡스 주식회사 기할당 작업을 이전 할당 가능한 rtv 시스템
KR20230116223A (ko) 2022-01-28 2023-08-04 현대무벡스 주식회사 리어포크 타입 무인이송대차의 화물 적재 시스템

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KR20000051838A (ko) * 1999-01-27 2000-08-16 윤덕용 수직 주행 이동체의 위치 인식장치
JP3102491B2 (ja) * 1990-05-18 2000-10-23 株式会社日立製作所 位置検出方法、及び位置検出装置
JP3674978B2 (ja) * 1995-03-01 2005-07-27 株式会社デンソー 移動体の安全制御装置
KR200400810Y1 (ko) * 2005-08-17 2005-11-09 (주)디.에스.이 스팡글 공급기의 제어장치
KR100980000B1 (ko) * 2009-11-02 2010-09-03 김희수 자동대차의 위치정보 보정 및 제공시스템

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP3102491B2 (ja) * 1990-05-18 2000-10-23 株式会社日立製作所 位置検出方法、及び位置検出装置
JP3674978B2 (ja) * 1995-03-01 2005-07-27 株式会社デンソー 移動体の安全制御装置
KR20000051838A (ko) * 1999-01-27 2000-08-16 윤덕용 수직 주행 이동체의 위치 인식장치
KR200400810Y1 (ko) * 2005-08-17 2005-11-09 (주)디.에스.이 스팡글 공급기의 제어장치
KR100980000B1 (ko) * 2009-11-02 2010-09-03 김희수 자동대차의 위치정보 보정 및 제공시스템

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