Robot-conveyor calibration method, robot system and control system

Patent metadata

Field	Value
Publication number	US-11511435-B2
Application number	US-201716612955-A
Country	US
Kind code	B2
Filing date	May 22, 2017
Priority date	May 22, 2017
Publication date	Nov 29, 2022
Grant date	Nov 29, 2022

Abstract

A method for calibrating a robot coordinate system of a robot with a conveyor coordinate system of a movable conveyor member, the method including providing a sensor configured to detect positions of the robot in a non-contact manner; detecting a position of the robot when the conveyor member is positioned at a first operating position; detecting a position of the robot and/or of the conveyor member by the sensor in the sensor coordinate system when the conveyor member is positioned at a second operating position different from the first operating position; and determining a relationship between the robot coordinate system and the conveyor coordinate system based on at least one detected position of the robot in the sensor coordinate system. A robot system and a control system are also provided.

First claim

The invention claimed is:

1. A method for calibrating a robot coordinate system of a robot with a conveyor coordinate system of a movable conveyor member, the method comprising:
providing a sensor configured to detect positions of the robot in a non-contact manner;
detecting a position of the robot by the sensor in a sensor coordinate system of the sensor when the movable conveyor member is positioned at a first operating position, wherein a control system controls the sensor to detect the position of the robot when the movable conveyor member is positioned at the first operating position;
detecting a position of the robot and/or a position of the movable conveyor member by the sensor in the sensor coordinate system when the movable conveyor member is positioned at a second operating position different from the first operating position, wherein a control system controls the sensor to detect the position of the robot and/or the position of the movable conveyor member when the movable conveyor member is positioned at the second operating position;
determining a relationship between the robot coordinate system and the conveyor coordinate system based on at least one detected position of the robot in the sensor coordinate system; and
controlling the robot via the control system, wherein the control system calibrates the robot coordinate system with the conveyor coordinate system according to the relationship automatically.

2. The method according to claim 1 , wherein the robot includes a tool and wherein the position of the robot is a position of the tool.

3. The method according to claim 1 , wherein the method further includes detecting positions of the robot in different poses by the sensor in the sensor coordinate system when the movable conveyor member is in the first operating position and/or when the movable conveyor member is in the second operating position.

4. The method according to claim 1 , wherein the sensor is positioned on the movable conveyor member, and wherein the method includes detecting a position of the robot by the sensor in the sensor coordinate system when the movable conveyor member is positioned at the first operating position and detecting a position of the robot by the sensor in the sensor coordinate system when the movable conveyor member is positioned at the second operating position.

5. The method according to claim 4 , wherein the method further comprises:
determining a movement direction of the movable conveyor member in the robot coordinate system based on the detected positions of the robot in the sensor coordinate system; and
determining a relationship between the robot coordinate system and the conveyor coordinate system based on the determined movement direction of the movable conveyor member.

6. The method according to claim 4 , wherein the robot constitutes a first robot and wherein the method further comprises:
moving the movable conveyor member from the second operating position to a third operating position;
detecting a position of a second robot by the sensor in the sensor coordinate system when the movable conveyor member is positioned at the third operating position;
moving the movable conveyor member from the third operating position to a fourth operating position;
detecting a position of the second robot by the sensor in the sensor coordinate system when the movable conveyor member is positioned at the fourth operating position; and
determining a relationship between a robot coordinate system of the second robot and the conveyor coordinate system based on the detected positions of the second robot in the sensor coordinate system.

7. The method according to claim 4 , wherein the relationship between the sensor coordinate system and the conveyor coordinate system is known beforehand.

8. The method according to claim 4 , wherein the sensor is additionally configured to detect positions of the movable conveyor member in a non-contact manner.

9. The method according to claim 8 , wherein the method further comprises:
detecting a position of the movable conveyor member by the sensor in the sensor coordinate system; and
determining a relationship between the sensor coordinate system and the conveyor coordinate system based on the detected position of the movable conveyor member in the sensor coordinate system.

10. The method according to claim 9 , wherein at least one calibration marker is provided on the movable conveyor member for the detection of the position of the movable conveyor member.

11. The method according to claim 10 , wherein the position of the at least one calibration marker in the conveyor coordinate system is known beforehand.

12. The method according to claim 1 , wherein the sensor is positioned on a stationary structure such that the movable conveyor member moves relative to the sensor and wherein the sensor is additionally configured to detect positions of the movable conveyor member in a non-contact manner.

13. The method according to claim 12 , wherein at least one calibration marker is provided on the movable conveyor member for the detection of the position of the movable conveyor member, and the method further comprises:
detecting a position of the at least one calibration marker by the sensor in the sensor coordinate system when the movable conveyor member is positioned at the first operating position;
detecting a position of the at least one calibration marker by the sensor in the sensor coordinate system when the movable conveyor member is positioned at the second operating position;
determining a movement direction of the movable conveyor member in the robot coordinate system based on the detected positions of the at least one calibration marker in the sensor coordinate system; and
determining a relationship between the robot coordinate system and the conveyor coordinate system based on the determined movement direction of the movable conveyor member.

14. A robot system comprising at least one robot, a movable conveyor member, and a sensor configured to detect positions of the robot in a non-contact manner, wherein the robot system is configured to:
detect a position of the robot by the sensor in a sensor coordinate system of the sensor when the movable conveyor member is positioned at a first operating position, wherein a control system controls the sensor to detect the position of the robot when the movable conveyor member is positioned at the first operating position;
detect a position of the robot and/or a position of the movable conveyor member by the sensor in the sensor coordinate system when the conveyor member is positioned at a second operating position different from the first operating position, wherein the control system controls the sensor to detect the position of the robot and/or the position of the movable conveyor member when the movable conveyor member is positioned at the second operating position;
determine a relationship between a robot coordinate system of the robot and a conveyor coordinate system of the movable conveyor member based on at least one detected position of the robot in the sensor coordinate system; and
control the robot via the control system, wherein the control system calibrates the robot coordinate system with the conveyor coordinate system according to the relationship automatically.

15. A control system for calibrating a robot coordinate system of a robot with a conveyor coordinate system of a movable conveyor member in a robot system comprising the robot, the movable conveyor member and a sensor configured to detect positions of the robot in a non-contact manner, the control system includin

Assignees

• Abb Schweiz Ag

Inventors

• Lager Anders
• Holmberg Johnny
• Wahlström Magnus
• Stenbacka Michael

Classifications

• B25J9/1692 Primary

  Calibration of manipulator · CPC title

• B25J9/1697

  Vision controlled systems · CPC title

• B25J9/0093 Primary

  co-operating with conveyor means · CPC title