Event-Based Redundancy Angle Configuration for Articulated-Arm Robots

Patent metadata

Field	Value
Publication number	US-2016129588-A1
Application number	US-201514930529-A
Country	US
Kind code	A1
Filing date	Nov 2, 2015
Priority date	Nov 7, 2014
Publication date	May 12, 2016
Grant date	—

Abstract

The invention relates to a method and a system for controlling a robot, which has at least one redundant degree of freedom. The method according to the invention prevents the robot from colliding with its surrounding environment and/or from getting into an inconvenient position as a result of its redundancy, and does so without causing any disadvantageous displacement of the tool center point.

First claim

1 . A method for controlling a hand-guided multi-axle manipulator, in particular an articulated-arm robot, the axes of which are equipped with torque sensors to register the torques acting on the axes, wherein the manipulator has at least one redundant degree of freedom, and wherein the manipulator has a tool center point, which includes the following method steps:
defining, for at least one of a plurality of joints of the manipulator, a range in which the joint of the manipulator can move freely according to the overall movement of the manipulator; guiding of the tool center point of the manipulator by hand; determining whether the joint has reached a limit of the range defined for the joint; and adjusting of the movement of the manipulator in response to the determination that the joint has reached the limit of the range defined for the joint, so that a movement of the joint through the limit is counteracted, without the tool center point of the robot being displaced as a result of the counteraction.

2 . The method according to claim 1 , wherein the adjustment of the movement comprises at least one of a change in the stiffness of the joints of the manipulator or an application of a force.

3 . The method according to claim 2 , wherein the adjustment of the movement pertains to the one joint which has reached a limit of the range defined for the joint.

4 . The method according to claim 1 , wherein the adjustment of the movement does not pertain to any of the other joints.

5 . The method according to claim 1 , wherein the manipulator has at least six axes A 1 to A 6 and the adjustment of the movement is a change in the stiffness of the joints of the axes A 3 or A 4 of the manipulator, wherein the joints of the axes A 3 or A 4 define an elbow joint of the manipulator.

6 . The method according to claim 1 , wherein the adjustment of the movement comprises a redirection of the movement of the one joint, which has reached the limit of the range defined for the joint.

7 . The method according to claim 1 , wherein the determination of whether the one joint of the manipulator is located outside of the range defined for the joint comprises an identification of rising and/or falling edges.

8 . The method according to claim 1 , wherein the determination is carried out while the manipulator is hand-guided in the force-compensated mode.

9 . The method according to claim 1 , wherein the adjustment of the movement of the manipulator can be manually triggered, and the adjustment then occurs automatically.

10 . A manipulator system, comprising a hand-guided multi-axle manipulator, in particular an articulated-arm robot, the axes of which are equipped with torque sensors to register the torques acting on the axes, wherein the manipulator has at least one redundant degree of freedom and wherein the manipulator has a tool center point, and wherein the system is equipped with a control device, which is configured to execute a method according to one of claims 1 - 9 .

Assignees

• Kuka Roboter Gmbh

Inventors

• Pfaff Bettina

Classifications

• G05B2219/39201

  Control of joint stiffness · CPC title

• B25J9/1666

  Avoiding collision or forbidden zones · CPC title

• B25J9/1643

  redundant control · CPC title

• B25J9/1674

  characterised by safety, monitoring, diagnostic · CPC title

• B25J9/06 Primary

  characterised by multi-articulated arms · CPC title