Robot system

• US 8,738,179 B2
• Filed: 11/24/2009
• Issued: 05/27/2014
• Est. Priority Date: 12/01/2008
• Status: Active Grant

• Current Assignee: Kabushiki Kaisha Yaskawa Denki
• Original Assignee: Kabushiki Kaisha Yaskawa Denki
• Inventors: Kouno, Dai, Nishimura, Takashi
• Primary Examiner(s): Tran, Dalena
• Application Number:
  US12/625,513
• Publication Number:
  US 20100138042A1
• Time in Patent Office: 1,645 Days
• Field of Search: 700/259, 700/183, 700/245, 700/180, 700/83, 700/97, 700/250, 700/253, 700/257, 701 23- 25, 318/567, 318/568.1, 31856812-56816, 901/3, 901/10, 901/46, 901/47
• US Class Current: 700/259
• CPC Class Codes: B25J 9/1664 characterised by motion, path, trajectory planning
• CPC Class Codes: G05B 2219/39393 Camera detects projected image, compare with reference image, position end effector
• CPC Class Codes: G05B 2219/40385 Compare offline teached point with online teached point, modify rest as function of error
• CPC Class Codes: G05B 2219/40425 Sensing, vision based motion planning
• CPC Class Codes: G05B 2219/40447 Bitmap based
• CPC Class Codes: G05B 2219/40519 Motion, trajectory planning

Abstract

Teaching images are acquired at a plurality of separate teaching points on a running route extending from a running start position to a goal position, respectively, under a first light environmental condition and a light environmental condition different from the first light environmental condition, and the teaching images are stored. A present teaching image serving as a target for a robot body in a running direction at present is selected from the stored teaching images. A driving mechanism is controlled so as to increase the matching degree between the present teaching image and an actual image taken by a camera.

Claims

1. A robot system comprising:

a robot body configured to run along a running route;

a driving mechanism configured to drive the robot body in a front-rear direction and a turning direction;

a driving control device mounted in the robot body and configured to control the driving mechanism; and

a camera mounted in the robot body and configured to take an actual image,

wherein the driving control device includes;

a teaching-image storage unit configured to store teaching images acquired at a plurality of separate teaching points on the running route from a running start position to a goal position under a first environmental lighting condition, and teaching images acquired at the plurality of separate teaching points on the running route under a second environmental lighting condition different from the first environmental lighting condition;

a teaching-image selection unit configured to select a present teaching image from the teaching images stored in the teaching-image storage unit, the present teaching image being a target for the robot body in a running direction at present; and

a running control unit configured to control the driving mechanism so as to increase a matching degree between the present teaching image selected by the teaching-image selection unit and the actual image taken by the camera.

2. The robot system according to claim 1,

wherein the teaching-image selection unit selects, as the present teaching image, a teaching image that has the highest matching degree with the actual image, from the teaching images stored in the teaching-image storage unit, and

wherein, when the matching degree between the present teaching image and the actual image becomes more than or equal to a threshold value, the teaching-image selection unit selects, as the next present teaching image, a teaching image that has the highest matching degree with the actual image, from the remaining teaching images.

3. The robot system according to claim 2, wherein, when the matching degree between the present teaching image and the actual image becomes less than or equal to a second threshold value, the teaching-image selection unit selects, as the next present teaching image, a teaching image that has the highest matching degree with the actual image, from the teaching images stored in the teaching-image storage unit.

4. The robot system according to claim 1,

wherein the teaching-image selection unit selects, as the present teaching image, a teaching image that has the highest matching degree with the actual image, from the teaching images stored in the teaching-image storage unit, and

wherein the running control unit controls a steering amount of the driving mechanism so as to increase the matching degree between the present teaching image and the actual image.

5. The robot system according to claim 1,

wherein the teaching-image selection unit acquires a present light environmental condition,

wherein the teaching-image selection unit selects, as the present teaching image, a teaching image that has the highest matching degree with the actual image, from the teaching images corresponding to the acquired present light environmental condition, and,

wherein, when the matching degree between the present teaching image and the actual image becomes more than or equal to a threshold value, the teaching-image selection unit selects, as the next present teaching image, a teaching image that has the highest matching degree with the actual image, from the remaining teaching images.

6. The robot system according to claim 1, wherein the camera acquires actual images at the plurality of image-taking points on the running route during autonomous running of the robot body, and add the actual images as teaching images to the teaching-image storage unit.

7. The robot system according to claim 6, wherein the teaching images are added to the teaching-image storage unit during autonomous running of the robot body only when the matching degree of the teaching image that has the highest matching degree is less than or equal to a third threshold value.

8. The robot system according to claim 1, wherein the light environmental condition includes a condition concerning a lighting state of the running route.

9. The robot system according to claim 1, wherein the light environmental condition includes a condition concerning a present time.

10. The robot system according to claim 1,

wherein the camera includes a first camera mounted in the robot body and configured to take an image in a frontward direction from the robot body, and a second camera mounted in the robot body and configured to take an image in a rearward direction from the robot body, and

wherein the running control unit controls the driving mechanism so that the robot body runs along the running route, on the basis of results of comparison between the teaching images stored in the teaching-image storage unit, and a first acquired image taken by the first camera and a second acquired image taken by the second camera.

11. The robot system according to claim 1,

wherein the teaching-image storage unit is configured to store a first teaching image acquired at a first separate teaching point of the plurality of separate teaching points under the first environmental lighting condition, and a second teaching image acquired at the first separate teaching point of the plurality of separate teaching points under the second environmental lighting condition,

wherein the teaching-image storage unit is configured to store a third teaching image acquired at a second separate teaching point of the plurality of separate teaching points under the first environmental lighting condition, and a fourth teaching image acquired at the second separate teaching point of the plurality of separate teaching points under the second environmental lighting condition, and

wherein the teaching-image selection unit configured to select the present teaching image from the first, second, third, and fourth teaching images stored in the teaching-image storage unit.

12. A robot system comprising:

a robot body configured to run along a running route;

a driving mechanism configured to drive the robot body in a front-rear direction and a turning direction;

a driving control device mounted in the robot body and configured to control the driving mechanism;

a first camera mounted in the robot body and configured to take an actual image in a frontward direction from the robot body; and

a second camera mounted in the robot body and configured to take an actual image in a rearward direction from the robot body,

wherein the driving control device includes;

a teaching-image storage unit configured to store teaching images including image data acquired beforehand along the running route at a plurality of separate teaching points on the running route; and

a running control unit configured to control the driving mechanism so that the robot body runs along the running route, on the basis of results of comparison between the teaching images stored in the teaching-image storage unit, and both a first acquired image taken by the first camera and a second acquired image taken by the second camera.

13. The robot system according to claim 12, wherein the first camera and the second camera are arranged in a manner such as to be opposite in an image-taking direction.

14. The robot system according to claim 12,

wherein the teaching-image storage unit stores teaching images for the first camera and teaching images for the second camera, and

wherein the running control unit controls the driving mechanism on the basis of a result of comparison between the first acquired image and the teaching images for the first camera and a result of comparison between the second acquired image and the teaching images for the second camera.

15. The robot system according to claim 12,

wherein the first camera is provided parallel to and offset from a center axis of the robot body, and

wherein the second camera is point-symmetrical with the first camera about a turning center of the robot body.

16. The robot system according to claim 12, wherein the first acquired image and the second acquired image used by the running control unit to control the driving mechanism are both acquired when the robot body is at a same location along the running route.