Method For Avoiding Collisions Between Two Robots

• US 20180029233A1
• Filed: 02/13/2015
• Published: 02/01/2018
• Est. Priority Date: 02/13/2015
• Status: Active Grant

• Current Assignee: ABB Schweiz AG (ABB Limited)
• Original Assignee: ABB Schweiz AG (ABB Limited)
• Inventors: LAGER, Anders
• Granted Patent: US 10,766,139 B2
• Time in Patent Office: Days
• CPC Class Codes: B25J 9/1676 Avoiding collision or forbidden zones
• CPC Class Codes: G05B 2219/39135 For multiple manipulators operating at same time, avoid collision
• CPC Class Codes: G05B 2219/40497 Collision monitor controls planner in real time to replan if collision
• CPC Class Codes: G05B 2219/45063 Pick and place manipulator

Abstract

A method for avoiding collisions between two robots providing first movement information related to a first robot movement; determining for a plurality of second robot movements whether they involve a risk for collision between the first and second robots; and executing one of the second robot movements. Information about a movement of one robot enables a robot controller of another robot with an overlapping work area to select among available robot movements an appropriate one that does not involve a risk for collision between the two robots.

Claims

1. A method for avoiding collisions between two robots in a robot system comprising a first robot having a first work area and a second robot having a second work area, the first work area overlapping with the second work area to thereby define an overlapping work area, the method comprising the steps of:

providing first movement information related to a first robot movement which is to be executed by the first robot;

retrieving the first movement information;

determining for a plurality of second robot movements whether they involve a risk for collision between the first and second robots; and

executing one of the second robot movements.

2. The method according to claim 1, wherein the method allows the first and second robots to simultaneously operate within the overlapping work area.

3. The method according to claim 1, wherein the first movement information comprises at least one position of the first robot.

4. The method according to claim 3, wherein the first movement information comprises a first start position and a first end position.

5. The method according to claim 4, wherein the first movement information further comprises a path between the first start position and the first end position.

6. The method according to claim 1, wherein the first and second robots are configured to carry out a pick and place task such that at each point of time the number of available robot movements is related to the number of respective items or empty places that are within or are about to be within the work area of the respective robot, and the plurality of second robot movements is selected among the available robot movements.

7. The method according to claim 6, wherein the plurality of second robot movements comprises all available robot movements.

8. The method according to claim 1, wherein the method further comprises the step of saving the first movement information in a digital memory.

9. The method according to claim 8, wherein the method further comprises the step of removing the first movement information from the digital memory.

11. The method according to claim 2, wherein the first movement information comprises at least one position of the first robot.

12. The method according to claim 2, wherein the first and second robots are configured to carry out a pick and place task such that at each point of time the number of available robot movements is related to the number of respective items or empty places that are within or are about to be within the work area of the respective robot, and the plurality of second robot movements is selected among the available robot movements.

13. The method according to claim 2, wherein the method further comprises the step of saving the first movement information in a digital memory.

10. A robot system configured to carry out a pick and place task, the robot system comprising a first robot having a first work area and a second robot having a second work area, the first work area overlapping with the second work area to thereby define an overlapping work area, and at least one robot controller for controlling movements of the first and second robots, wherein the robot controller is configured to execute a method comprising the steps of:

providing first movement information related to a first robot movement which is to be executed by the first robot;

retrieving the first movement information;

determining for a plurality of second robot movements whether they involve a risk for collision between the first and second robots; and

executing one of the second robot movements.