Transport system and transport method
A transport system includes: an image capturer included in a transport vehicle; a positional deviation detector that detects a positional deviation between a pre-correction position at a time when the article is placed on a reference transfer destination and a reference placement position; a corresponding relationship calculator that finds a pixel deviation between a pre-correction image and a post-correction image and calculates an actual deviation amount per unit pixel, the pre-correction image being captured at an initial position of the transport vehicle by the image capturer, and the post-correction image being captured by the image capturer at a position of the transport vehicle deviated by the positional deviation; and the correction amount calculator that finds a pixel deviation between the post-correction image and a transfer destination image captured of another transfer destination and calculates a correction amount from the pixel deviation and the actual deviation amount per unit pixel.
1. A transport system including:
a track installed across multiple transfer destinations including a reference transfer destination; and
a plurality of transport vehicles each including a traveling body that travels on the track, a holder that holds an article, and a transferer including a lifter provided in the traveling body and raises or lowers the holder,
wherein the transport vehicle which has stopped to correspond to the transfer destination receives or delivers an article from or to the transfer destination by the transferer.
the transport system comprising:
an image capturer provided in the transport vehicle and captures an image thereunder;
a positional deviation detector that detects a positional deviation in a horizontal direction between a position of an article placed on the reference transfer destination by the transport vehicle having stopped at an initial position corresponding to the reference transfer destination and lowering the holder by the lifter and a reference placement position preliminarily determined on the reference transfer destination;
a corresponding relationship calculator that finds a pixel deviation between a pre- correction image and a post-correction image and calculates an actual deviation amount per unit pixel from the pixel deviation and the positional deviation, the pre-correction image being captured, by the image capturer of the transport vehicle having stopped at the initial position, of the reference transfer destination at a predetermined height at which the holder is not lowered to a height at which the article is placed at the reference transfer destination, and the post-correction image being captured, by the image capturer of the transport vehicle having stopped at a position deviated from the initial position by the positional deviation, of the reference transfer destination at the predetermined height; and
a correction amount calculator that finds a pixel deviation between the post-correction image and a transfer destination image captured, by the image capturer of the transport vehicle having stopped at an initial position corresponding to another transfer destination or at a position deviated from the initial position by the positional deviation, of the another transfer destination at the predetermined height and that calculates, from the pixel deviation and the actual deviation amount per unit pixel, a correction amount of a stop position at a time when the transport vehicle transfers the article to the another transfer destination.
2. The transport system according to claim 1 , wherein:
a stop indicator is provided at each of the plurality of transfer destinations so as to correspond thereto,
the transport vehicle includes a stop indicator detector which detects the stop indicator, and
the initial position corresponding to the transfer destination is a stop position of the transport vehicle in which the traveling body has stopped traveling as triggered by detection of the stop indicator.
3. The transport system according to claim 1 , wherein:
the image capturer is provided on the holder, and
the predetermined height is a height of the image capturer in a state where the lifter has raised the holder to an uppermost position thereof.
4. The transport system according to claim 1 , wherein a coordinate value in one coordinate system set in a horizontal direction and an angle in a direction of rotation about an axis in a vertical direction are used for the correction amount.
5. The transport system according to claim 1 , wherein the transport vehicle which is not involved in the calculation of the correction amount includes a corrector which further corrects the correction amount calculated by the correction amount calculator by using a positional deviation of the transport vehicle itself in the horizontal direction calculated by the positional deviation detector according to the reference transfer destination.
6. The transport system according to claim 1 , wherein:
each of the plurality of transfer destinations includes a positioner to position the article on a placement surface for the article,
the corresponding relationship calculator finds a pixel deviation between an image of the positioner in the pre-correction image and an image of the positioner in the post-correction image, and calculates the actual deviation amount per unit pixel from the pixel deviation and the positional deviation, and
the correction amount calculator finds a pixel deviation between an image of the positioner in the transfer destination image and an image of the positioner in the post-correction image and calculates the correction amount from the pixel deviation and the actual deviation amount per unit pixel.
7. The transport system according to claim 1 , the transport system further comprising:
a teaching unit that can be held by the holder, wherein
the teaching unit includes a supporter which supports the image capturer.
8. The transport system according to claim 7 , wherein the supporter includes a posture maintainer that maintains a posture of the image capturer so that a direction of image capturing of the image capturer is downward.
9. A transport method in a transport system including:
a track installed across multiple transfer destinations including a reference transfer destination; and
a plurality of transport vehicles each including a traveling body that travels on the track, a holder that holds an article, and a transferer including a lifter provided in the traveling body and raises or lowers the holder,
wherein the transport vehicle which has stopped to correspond to the transfer destination receives or delivers an article from or to the transfer destination by the transferer,
the transport method comprising:
providing in the transport vehicle an image capturer which captures an image thereunder;
detecting a positional deviation in a horizontal direction between a position of an article placed on the reference transfer destination by the transport vehicle having stopped at an initial position corresponding to the reference transfer destination and lowering the holder by the lifter and a reference placement position preliminarily determined on the reference transfer destination;
finding a pixel deviation between a pre-correction image and a post-correction image and calculating an actual deviation amount per unit pixel from the pixel deviation and the positional deviation, the pre-correction image being captured, by the image capturer of the transport vehicle having stopped at the initial position, of the reference transfer destination at a predetermined height at which the holder is not lowered to a height at which the article is placed at the reference transfer destination, and the post-correction image being captured, by the image capturer of the transport vehicle having stopped at a position deviated from the initial position by the positional deviation, of the reference transfer destination at the predetermined height; and
finding a pixel deviation between the post-correction image and a transfer destination image captured, by the image capturer of the transport vehicle having stopped at an initial position corresponding to another transfer destination or at a position deviated from the initial position by the positional deviation, of the another transfer destination at the predetermined height and calculating, from the pixel deviation and the actual deviation amount per unit pixel, a correction amount of a stop position at a time when the transport vehicle transfers the article to the another transfer destination.
10. The transport system according to claim 2 , wherein:
the image capturer is provided on the holder, and
the predetermined height is a height of the image capturer in a state where the lifter has raised the holder to an uppermost position thereof.
11. The transport system according to claim 2 , wherein a coordinate value in one coordinate system set in a horizontal direction and an angle in a direction of rotation about an axis in a vertical direction are used for the correction amount.
12. The transport system according to claim 3 , wherein a coordinate value in one coordinate system set in a horizontal direction and an angle in a direction of rotation about an axis in a vertical direction are used for the correction amount.
13. The transport system according to claim 2 , wherein the transport vehicle which is not involved in the calculation of the correction amount includes a corrector which further corrects the correction amount calculated by the correction amount calculator by using a positional deviation of the transport vehicle itself in the horizontal direction calculated by the positional deviation detector according to the reference transfer destination.
14. The transport system according to claim 3 , wherein the transport vehicle which is not involved in the calculation of the correction amount includes a corrector which further corrects the correction amount calculated by the correction amount calculator by using a positional deviation of the transport vehicle itself in the horizontal direction calculated by the positional deviation detector according to the reference transfer destination.
15. The transport system according to claim 4 , wherein the transport vehicle which is not involved in the calculation of the correction amount includes a corrector which further corrects the correction amount calculated by the correction amount calculator by using a positional deviation of the transport vehicle itself in the horizontal direction calculated by the positional deviation detector according to the reference transfer destination.
16. The transport system according to claim 2 , wherein:
each of the plurality of transfer destinations includes a positioner to position the article on a placement surface for the article,
the corresponding relationship calculator finds a pixel deviation between an image of the positioner in the pre-correction image and an image of the positioner in the post-correction image, and calculates the actual deviation amount per unit pixel from the pixel deviation and the positional deviation, and
the correction amount calculator finds a pixel deviation between an image of the positioner in the transfer destination image and an image of the positioner in the post-correction image and calculates the correction amount from the pixel deviation and the actual deviation amount per unit pixel.
17. The transport system according to claim 3 , wherein:
each of the plurality of transfer destinations includes a positioner to position the article on a placement surface for the article,
the corresponding relationship calculator finds a pixel deviation between an image of the positioner in the pre-correction image and an image of the positioner in the post-correction image, and calculates the actual deviation amount per unit pixel from the pixel deviation and the positional deviation, and
the correction amount calculator finds a pixel deviation between an image of the positioner in the transfer destination image and an image of the positioner in the post-correction image and calculates the correction amount from the pixel deviation and the actual deviation amount per unit pixel.
18. The transport system according to claim 4 , wherein:
each of the plurality of transfer destinations includes a positioner to position the article on a placement surface for the article,
the corresponding relationship calculator finds a pixel deviation between an image of the positioner in the pre-correction image and an image of the positioner in the post-correction image, and calculates the actual deviation amount per unit pixel from the pixel deviation and the positional deviation, and
the correction amount calculator finds a pixel deviation between an image of the positioner in the transfer destination image and an image of the positioner in the post-correction image and calculates the correction amount from the pixel deviation and the actual deviation amount per unit pixel.
19. The transport system according to claim 5 , wherein:
each of the plurality of transfer destinations includes a positioner to position the article on a placement surface for the article,
the corresponding relationship calculator finds a pixel deviation between an image of the positioner in the pre-correction image and an image of the positioner in the post-correction image, and calculates the actual deviation amount per unit pixel from the pixel deviation and the positional deviation, and
the correction amount calculator finds a pixel deviation between an image of the positioner in the transfer destination image and an image of the positioner in the post-correction image and calculates the correction amount from the pixel deviation and the actual deviation amount per unit pixel.