Method And Apparatus For Controlling A Robot

Patent metadata

Field	Value
Publication number	US-2016016314-A1
Application number	US-201514802418-A
Country	US
Kind code	A1
Filing date	Jul 17, 2015
Priority date	Jul 17, 2014
Publication date	Jan 21, 2016
Grant date	—

Abstract

A method for controlling a robot in at least one pose of the robot wherein the robot can be operated in either a first mode of operation or a second mode of operation. In the second mode of operation the robot can be moved by manually applying a guiding force to the robot. The method includes determining a distance of a state variable of the robot from a first limit and then triggering a safety response when the distance satisfies a first condition and the robot is operating in the first mode of operation. When the robot is operating in the second mode of operation and the distance satisfies the first condition, the method includes not triggering the safety response, and motorically applying a positioning force to the robot in dependence on the determined distance so that the distance can be reduced when the robot is unobstructed.

First claim

What is claimed is:

1 . A method for controlling a robot in at least one pose of the robot and in one of a first mode of operation or a second mode of operation, wherein the robot can be moved by manually applying a guiding force to the robot in the second mode of operation, the method comprising:
determining a distance of a state variable of the robot from a first limit; when the robot is operating in the first mode of operation, triggering a safety response when the distance satisfies a first condition; and when the robot is operating in the second mode of operation and the distance satisfies the first condition, then:
not triggering the safety response, and
motorically applying a positioning force to the robot in dependence on the determined distance so that the distance can be reduced when the robot is unobstructed.

2 . The method of claim 1 , further comprising:
emitting a signal when the robot is operating in the second mode of operation and the distance satisfies the first condition.

3 . The method of claim 2 , wherein the signal is at least one of:
an optic signal; an acoustic signal; or a haptic signal.

4 . The method of claim 2 , wherein:
an output of a distance means for determining the distance is connected with a safety means for triggering the safety response in the first mode of operation; and the output of the distance means is connected with a signal means for emitting the signal in the second mode of operation.

5 . The method of claim 1 , further comprising:
determining a second distance of a state variable of the robot from a second limit that is different from the first limit; and triggering a safety response in the second mode of operation when the second distance satisfies a second condition, or when a third distance of a state variable of the robot from a third limit satisfies a third condition that is different from the first condition.

6 . The method of claim 5 , wherein the safety response is triggered without motorically applying the positioning force on the robot to reduce the distance.

7 . The method of claim 1 , wherein at least one state variable of the robot includes at least one of:
at least one position coordinate and/or orientation coordinate of at least one robot-fixed reference; at least a time derivative of the at least one position coordinate and/or orientation coordinate; at least one joint coordinate of the robot; or at least one time derivative of the at least one joint coordinate.

8 . The method of claim 7 , wherein the at least one robot fixed reference is a tool center point.

9 . The method of claim 1 , wherein at least one safety response of the robot comprises at least one of:
shutting down the robot; or separation of at least one drive of the robot from a power supply.

10 . The method of claim 9 , wherein shutting down the robot comprises shutting down via at least a brake and/or at least a drive of the robot.

11 . The method of claim 1 , wherein at least one of the limits is dependent on one of the state variables.

12 . The method of claim 1 , wherein at least one of the limits is defined by at least two hypersurfaces and/or at least one curved hypersurface in a state space of the robot.

13 . The method of claim 12 , wherein the at least two hypersurfaces are parallel or non-parallel hypersurfaces.

14 . The method of claim 1 , further comprising:
automatedly moving the robot by program-control in the first mode of operation; or moving the robot by manual application of a guiding force on the robot.

15 . The method of claim 1 , further comprising:
moving the robot in the second mode of operation by manual application of a guiding force on the robot in such a way that the distance of the state variable of the robot from the first limit satisfies the first condition.

16 . A method for moving a robot by manual application of a guiding force on the robot, the method comprising:
determining distances of a state variable of the robot from at least two different specified references in a state space of the robot; identifying the smallest of the determined distances; and motorically applying a positioning force to the robot so as to reduce the smallest of the distances when the robot is unobstructed.

17 . The method of claim 16 , wherein the specified references in the state space of the robot include at least one of:
positions of a robot-fixed reference; poses of the robot; or structures in the state space of the robot.

18 . The method of claim 17 , wherein at least one of:
the position of a robot-fixed reference is a tool center point; the poses of the robot comprise a specified path of the robot; or the structures in the space state of the robot are at least one of virtual structures, walls, or coordinate systems.

19 . The method of claim 16 , further comprising displaying the reference in the state space of the robot that exhibits the smallest determined distance.

20 . The method of claim 16 , further comprising flexibly controlling the robot so as to be movable by manual application of a guiding force to the robot.

21 . The method of claim 20 , wherein the flexible control is at least one of a force-regulated control or gravity-compensated control.

22 . A device for controlling a robot that is operable in a first mode of operation or a second mode of operation, wherein the robot can be moved by manually applying a guiding force to the robot in the second mode of operation, the device including program code stored on a non-transitory machine-readable medium that, when executed by the device, causes the device to:
determine a distance of a state variable of the robot from a first limit; when the robot is operating in the first mode of operation, trigger a safety response when the distance satisfies a first condition; and when the robot is operating in the second mode of operation and the distance satisfies the first condition, then:
not trigger the safety response, and
motorically apply a positioning force to the robot in dependence on the determined distance so that the distance can be reduced when the robot is unobstructed.

23 . A computer program product for controlling a robot that is operable in a first mode of operation or a second mode of operation, wherein the robot can be moved by manually applying a guiding force to the robot in the second mode of operation, the computer program product having programming code stored on a non-transitory machine-readable medium, the programming code configured to, when executed by a computer, cause the computer to:
determine a distance of a state variable of the robot from a first limit; when the robot is operating in the first mode of operation, trigger a safety response when the distance satisfies a first condition; and when the robot is operating in the second mode of operation and the distance satisfies the first condition, then:
not trigger the safety response, and
motorically apply a positioning force to the robot in dependence on the determined distance so that the distance can be reduced when the robot is unobstructed.

Assignees

• Kuka Roboter Gmbh

Inventors

• Hietmann Gerhard
• Ueberle Marc-Walter
• Hartmann Christian
• Schwarz Richard
• Rudolf Richard

Classifications

• B25J9/1676 Primary

  Avoiding collision or forbidden zones · CPC title

• Y10S901/09

  Closed loop, sensor feedback controls arm movement · CPC title

• B25J9/1674 Primary

  characterised by safety, monitoring, diagnostic · CPC title

• G05B2219/49141

  Detect near collision and slow, stop, inhibit movement tool · CPC title

• G05B2219/40371

  Control trajectory to avoid joint limit as well as obstacle collision · CPC title