JP2008083777A - Method and device for guiding unmanned carrier - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To enable an unmanned carrier to independently travel not by using a sign or the like but by using a GPS receiver and a laser radar to switch it indoors and outdoors. <P>SOLUTION: The method and device for guiding an unmanned carrier is configured to selectively input a first error estimation value (13a) to be acquired from a GPS receiver (11) and a first Kalman filter (13), and a second error estimation value (25a) to be acquired by a laser radar (21), a background map information (22), a position calculation part (23), and a second Kalman filter (25), to an inertial navigation arithmetic part (16) to acquire a current location/azimuth signal (17). <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a guide method and apparatus for an automatic guided vehicle, and in particular, selectively inputs a GPS signal of a GPS receiver and a position signal of a laser radar device to an inertial navigation calculation unit of the automatic guided vehicle, and outputs the GPS signal outdoors. The present invention relates to a novel improvement for performing unmanned traveling by obtaining a current position / orientation signal of an automatic guided vehicle with high accuracy without using a guide sign body or the like by using a position signal indoors or outside.

Conventionally, as this type of automatic guided vehicle guiding method and apparatus, for example, configurations disclosed in Patent Documents 1 and 2 can be given.
That is, in the guidance device in Patent Document 1, as shown in FIG. 2, the unmanned conveyance that travels on the commanded travel route with the magnetic sensor 1, the vehicle speed sensor 2, and the gyro 3 mounted and calculating the travel distance and the traveling direction is performed. In the vehicle guidance device, a wheel diameter sensor 4 for measuring the wheel diameter is provided in the automatic guided vehicle, and the movement distance calculated from the measurement signal of the vehicle speed sensor 2 is obtained by correcting the measurement signal of the wheel diameter sensor 4. ing.

  In addition, in the guidance device in Patent Document 2, in an automatic guided vehicle that travels while calculating its own position and traveling direction by mounting a travel distance detector and a gyro 3, on the traveling center lines of the front and rear portions of the automatic guided vehicle. In addition to providing an orientation detector that detects the amount of displacement in the width direction of the vehicle body, an ID tag detector that detects absolute position information is provided in the center of the automated guided vehicle, and the orientation detection is performed at a predetermined position in the travel route. The ID tag 5 storing the azimuth sign and the absolute position information is provided opposite the detector and the ID tag detector, and the amount of deviation between the azimuth angle of the automatic guided vehicle and the absolute position is determined from the detection information of the both position detector. The current position and direction are corrected by calculation.

JP 2002-23847 A JP 2001-209429 A

Since the conventional automatic guided vehicle guiding method and apparatus are configured as described above, the following problems exist.
That is, in the configuration of the above-described Patent Document 1, many sensors such as a magnetic sensor and a wheel diameter sensor must be mounted on the automatic guided vehicle, and a plurality of signs are necessary on the conveyance path in order to use many sensors. In addition, the configuration of both the automatic guided vehicle and the transport path is complicated.
Moreover, in the structure of the above-mentioned patent document 2, while providing the azimuth | direction detector which detects the deviation | shift amount of the position of a vehicle body width direction in the front part and rear part of an automatic guided vehicle, in order to detect absolute position information in a center part. In addition to providing ID tag detectors and providing ID tags storing direction signs and absolute position information on the conveyance path, it is necessary to provide many signs, and the configuration of both the automatic guided vehicle and the conveyance path is complicated. It was.

  The guided vehicle guided method according to the present invention includes a first error estimated value obtained by a GPS receiver and a first Kalman filter, a second error estimated value obtained by a laser radar, background map information, a position calculation unit, and a second Kalman filter. Is selectively input to an inertial navigation calculation unit to which a gyro signal, a vehicle speed pulse, and a steering angle are input, and a current position / orientation signal of an automatic guided vehicle equipped with the GPS receiver and the laser radar is obtained. The satellite observation value obtained by comparing the GPS signal from the GPS receiver with the current position / orientation signal by the first comparator is processed by the first Kalman filter to obtain the first error estimated value. And obtaining a laser radar observation value obtained by comparing the position signal from the position calculation unit and the current position / orientation signal with a second comparator. To obtain the second error estimated value, and a first switch is provided between the inertial navigation calculation unit and each Kalman filter, and the inertial navigation calculation unit and each comparator A second switch is provided between the first and second automatic switches, and the guidance device for the automatic guided vehicle according to the present invention includes a first error estimated value obtained by the GPS receiver and the first Kalman filter, a laser radar, The background map information and the second error estimated value obtained by the position calculation unit and the second Kalman filter are selectively input to an inertial navigation calculation unit to which a gyro signal, a vehicle speed pulse, and a steering angle are input, and the GPS reception is performed. A current position / orientation signal of an automated guided vehicle equipped with a detector and a laser radar, and the GPS signal from the GPS receiver and the current position / orientation signal A satellite observation value obtained by comparison with one comparator is processed by the first Kalman filter to obtain the first error estimated value, and a second comparison is made between the position signal from the position calculation unit and the current position / orientation signal. A laser radar observation value obtained by comparison with a detector is processed by the second Kalman filter to obtain the second error estimated value, and between the inertial navigation calculation unit and each Kalman filter, the first error estimation value is obtained. A switch is provided, and a second switch is provided between the inertial navigation calculation unit and each comparator.

Since the guided method and apparatus for an automated guided vehicle according to the present invention are configured as described above, the following effects can be obtained.
In other words, inertial navigation calculation is performed using a GPS receiver and a laser radar device, and switching between the outdoors and indoors is conducted independently, so that there is no need for any guidance signs on the conveyance path as in the past, and reliability Highly automated guided vehicles can be realized at a minimum cost.
In addition, the manufacturing cost on the vehicle body side and the conveyance path can be significantly reduced as compared with the conventional case.

  The present invention selectively inputs the GPS signal of the GPS receiver and the position signal of the laser radar device to the inertial navigation calculation unit of the automatic guided vehicle, uses the GPS signal outdoors, and uses the position signal indoors. It is an object of the present invention to provide an automatic guided vehicle guiding method and apparatus capable of obtaining unmanned traveling by obtaining a current position / orientation signal of the automatic guided vehicle with high accuracy without using a guide sign etc. .

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of a guided method and apparatus for an automated guided vehicle according to the present invention will be described with reference to the drawings.
The same reference numerals are used for the same or equivalent parts as in the conventional example.
1 is a known GPS receiver mounted on the automated guided vehicle 50, and a GPS signal 11a from the GPS receiver 11 of the GPS receiver 10 is input to the first comparator 12, The satellite observation value 12 a from the first comparator 12 is input to the first Kalman filter 13.

  The first estimated error value 13a from the first Kalman filter 13 is input via a first switch 14 to a known inertial navigation calculation unit 16 to which the gyro signal 3a of the gyro 3, the vehicle speed pulse 2, and the steering angle 15 are input. The inertial navigation calculation unit 16 outputs a current position / orientation signal 17, and the inertial navigation calculation unit 16 constitutes a position / orientation calculation device 18.

  A laser radar device 20 is provided separately from the GPS receiver 10, and a radar signal 21a from the laser radar 21 of this laser radar device 20 uses background map information 22 and calculates a position by comparison with this. This is input to the calculation unit 23.

The position signal 23 a from the position calculation unit 23 is input to the second comparator 24, and the laser radar observation value 24 a from the second comparator 24 is input to the second Kalman filter 25.
The second error estimated value 25 a from the second Kalman filter 25 is configured to be input to the inertial navigation calculation unit 16 via the first switch 14.

  The current position / orientation signal 17 from the inertial navigation calculation unit 16 is input to the comparators 12 and 24 via the second switch 26, and is compared with the GPS signal 11a and the position signal 23a. The values 12a and 24a can be output.

  Next, the operation will be described. In FIG. 1, the first and second switches 14 and 26 (each switch can be a mechanical switch, but are usually executed by software incorporated in the CPU) are switched in a solid line. The inertial navigation calculation is performed by the gyro 3, the vehicle speed pulse 2, and the steering angle 15, and the current position / orientation signal 17 is input to the first comparator 12.

  Since the current position / orientation signal 17 includes a cumulative error, it is compared with the current position information obtained from the GPS signal 11a, the error is estimated using the first Kalman filter 13, and the first error estimated value 13a is inertial. It is fed back to the navigation calculation unit 16 to correct the current position / orientation signal 17.

  When the switches 14 and 26 are switched to the positions indicated by the dotted lines, the GPS receiver 10 is switched to the laser radar device 20, and the radar signal 21a of the information on the peripheral object measured by the laser radar 21 is obtained. The position signal 23 a obtained by comparing with the surrounding background map information 22 previously held is compared with the current position / orientation signal 17, and the laser radar observation value 24 a is input to the second Kalman filter 25.

  The second estimated error value 25a from the second Kalman filter 25 is input to the inertial navigation calculation unit 16 via the first switch 14 and is feedback-calculated to improve the accuracy of the current position / orientation signal 17.

  Therefore, when the unmanned transport using the GPS receiver 10 is performed on a transport route with a good view of the outdoors, and the GPS signal 11a is interrupted by the unmanned transport vehicle 50 indoors or due to a shield or the like, the switches 14 and 26 are automatically operated. By comparing the information of the surrounding objects (buildings, utility poles, trees, etc.) obtained by scanning with the laser radar 21 with the built-in laser radar obstacle map (referred to as the background map). As described above, the current position / orientation signal 17 is obtained by the laser radar device 20.

That is, the position of the position signal 23a is compared with the current position / azimuth signal 17 of the inertial navigation calculation unit 16 based on the radar signal 21a when the GPS signal 11a is interrupted, and the result is sent to the second Kalman filter 25 as the laser radar observation value 24a. Input and process, and position / orientation error estimation is performed using the second error estimated value 25a.
The scale factor of the gyro 3, the vehicle speed pulse 2, and the steering angle 15 can be corrected by the inertial navigation calculation unit 16 from the second error estimated value 25a, and the current position / orientation signal 17 can be corrected.

It is a block diagram which shows the guidance method and apparatus of the automatic guided vehicle by this invention. It is a block diagram which shows a conventional structure.

Explanation of symbols

2 Vehicle speed pulse 3 Gyro 10 GPS receiver 11 GPS receiver 11a GPS signal 12 First comparator 12a Satellite observation value 13 First Kalman filter 13a First error estimated value 14 First switch 15 Steering angle 16 Inertial navigation calculation unit 17 Current position Azimuth signal 18 position / azimuth calculation device 20 laser radar device 21 laser radar 21a radar signal 22 background map information 23 position calculation unit 23a position signal 24 second comparator 24a laser radar observation value 25 second Kalman filter 25a second error estimation value 26 Second switch

Claims (6)

  The first error estimated value (13a) obtained by the GPS receiver (11) and the first Kalman filter (13), the laser radar (21), the background map information (22), the position calculation unit (23), and the second Kalman filter ( The second error estimation value (25a) obtained by 25) is selectively applied to the inertial navigation calculation unit (16) to which the gyro signal (3a), the vehicle speed pulse (2), and the steering angle (15) are input. An automated guided vehicle guidance method, comprising: inputting and obtaining a current position / direction signal (17) of the automated guided vehicle (50) equipped with the GPS receiver (11) and the laser radar (21).   A satellite observation value (12a) obtained by comparing the GPS signal (11a) from the GPS receiver (11) and the current position / azimuth signal (17) by the first comparator (12) is used as the first Kalman filter ( 13) to obtain the first error estimated value (13a), and the position signal (23a) from the position calculation unit (23) and the current position / orientation signal (17) to the second comparator (24 2. The automatic guided vehicle according to claim 1, wherein the laser radar observation value (24a) obtained by comparison in (1) is processed by the second Kalman filter (25) to obtain the second error estimated value (25a). Guidance method.   A first switch (14) is provided between the inertial navigation calculation unit (16) and the Kalman filters (13, 25), and the inertial navigation calculation unit (16) and the comparators (12, 24). A method for guiding a guided guided vehicle according to claim 2, wherein a second switch (26) is provided between the first and second switches.   The first error estimated value (13a) obtained by the GPS receiver (11) and the first Kalman filter (13), the laser radar (21), the background map information (22), the position calculation unit (23), and the second Kalman filter ( The second error estimation value (25a) obtained by 25) is selectively applied to the inertial navigation calculation unit (16) to which the gyro signal (3a), the vehicle speed pulse (2), and the steering angle (15) are input. An automatic guided vehicle guidance device, which receives the current position / direction signal (17) of the automated guided vehicle (50) equipped with the GPS receiver (11) and the laser radar (21).   A satellite observation value (12a) obtained by comparing the GPS signal (11a) from the GPS receiver (11) and the current position / azimuth signal (17) by the first comparator (12) is used as the first Kalman filter ( 13) to obtain the first error estimated value (13a), and the position signal (23a) from the position calculation unit (23) and the current position / orientation signal (17) to the second comparator (24 5. The automatic guided vehicle according to claim 4, wherein the laser radar observation value (24a) obtained by comparison in (1) is processed by the second Kalman filter (25) to obtain the second error estimated value (25a). Guidance device.   A first switch (14) is provided between the inertial navigation calculation unit (16) and the Kalman filters (13, 25), and the inertial navigation calculation unit (16) and the comparators (12, 24). A guided device for an automatic guided vehicle according to claim 5, wherein a second switch (26) is provided between the first and second switches.

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