Screwing device

Patent metadata

Field	Value
Publication number	US-11524405-B2
Application number	US-201816606998-A
Country	US
Kind code	B2
Filing date	Apr 18, 2018
Priority date	Apr 23, 2017
Publication date	Dec 13, 2022
Grant date	Dec 13, 2022

Abstract

A screwing device including: a container for screws; a manipulator having an effector to pick up a screw; an isolating unit connected to the container to provide the screw from the container at an interface such that a head of the screw is accessible to the effector; and a control unit to control the manipulator in executing a control program to perform operations including: guiding the effector along a trajectory having an orientation to the screw head at the interface, wherein the orientation is defined for locations along the trajectory; and executing force-regulated, impedance-regulated, and/or admittance-regulated periodic and closed tilting movements of the effector in relation to its orientation until a condition for a torque, a force, or a time for carrying out the tilting movements is reached or exceeded, and/or a force/torque and/or a position/speed signature at the effector is reached or exceeded, indicating successful pick-up of the screw.

First claim

The invention claimed is:

1. A screwing device comprising:
a storage container for screws having a screw head, a screw head drive, and a threaded pin;
a robot manipulator having an effector, the effector adapted to the screw head and the screw head drive, and embodied and configured to pick up and handle the screws;
an isolating unit connected to the storage container, the isolating unit comprising an interface at a known position, wherein the screw head of a respective screw isolated from the storage container is accessible to the effector at the interface; and
a control unit to control or regulate the robot manipulator to pick up the screw head of the respective screw in the effector, wherein the control unit is embodied and configured to execute a first control program to perform operations comprising:
guiding the effector by the robot manipulator along a predetermined trajectory T 1 having a target orientation O target,T1 (R T1 ) to the screw head of the respective screw provided at the interface, wherein along the trajectory T 1 for locations R T1 of the trajectory T 1 , the target orientation O target,T1 (R T1 ) of the effector is defined;
beginning at a predefined distance from the screw head of the respective screw, executing force-regulated and/or impedance-regulated and/or admittance-regulated periodic and closed tilting movements of the effector relative to the target orientation O target,T1 (R T1 ) by the robot manipulator until a predetermined limiting value condition G 1 of a torque acting on the effector and/or a predetermined limiting value condition G 2 of a force acting on the effector and/or a limiting value condition G 3 of a time for carrying out the tilting movements is reached or exceeded, and/or until a provided force/torque signature and/or a position/speed signature at the effector is reached or exceeded, indicating that picking up the respective screw by the screw head via the effector has been successfully completed within predefined tolerances.

2. The screwing device according to claim 1 , wherein the control unit is embodied and configured to execute a second control program to perform operations comprising:
guiding the respective screw picked up by the effector of the robot manipulator along a predetermined trajectory T 2 having a target orientation O target,T2 (R T2 ) of the threaded pin of the respective screw to a thread arranged at a position known down to a tolerance band, wherein the target orientation O target,T2 (R T2 ) of the threaded pin of the respective screw is defined along the trajectory T 2 for locations R T2 of the trajectory T 2 ; and
executing force-regulated and/or impedance-regulated and/or admittance-regulated rotational movements and/or tilting movements and/or translational movement patterns of the respective screw to introduce a free end of the threaded pin of the respective screw into the thread by the robot manipulator until a predetermined limiting value condition G 4 for a torque acting on the effector and/or a predetermined limiting value condition G 5 of a force acting on the effector is reached or exceeded, and/or until a provided force/torque signature and/or a position/speed signature on the effector is reached or exceeded, indicating that the free end of the threaded pin of the respective screw is successfully introduced into the thread.

3. The screwing device according to claim 2 , wherein the control unit is embodied and configured to execute a third control program to perform operations comprising:
after successful introduction of the free end of the threaded pin of the respective screw into the thread, performing force-regulated and/or impedance-regulated and/or admittance-regulated screwing of the respective screw into the thread until a predetermined limiting value condition G 6 for a torque acting on the effector and/or a predetermined limiting value condition G 7 for a force acting on the effector is reached or exceeded, and/or until a provided force/torque signature and/or a position/speed signature on the effector is reached or exceeded, indicating that the respective screw is successfully screwed into the thread.

4. The screwing device according to claim 3 , wherein the screwing device comprises a data interface to a data network, and the screwing device is configured and embodied to load the first control program and/or the second control program and/or the third control program and/or further control programs from the data network.

5. The screwing device according to claim 4 , wherein the screwing device is configured and embodied to load control and regulating parameters for the first control program and/or second control program and/or third control program and/or for further control programs from the data network.

6. The screwing device according to claim 4 , wherein the screwing device is configured and embodied to load control and regulating parameters for the first control program and/or the second control program and/or the third control program and/or for further control programs via a manual input interface of the screwing device and/or via a teach-in procedure, during which the robot manipulator is manually guided.

7. The screwing device according to claim 4 , wherein the screwing device is configured and embodied to control loading of the first control program and/or the second control program and/or the third control program and/or further control programs, and/or associated control and regulating parameters, from a remote station connected to the data network.

8. The screwing device according to claim 4 , wherein the screwing device is configured and embodied to transmit control programs provided locally at the screwing device and/or associated control and regulating parameters upon request, or autonomously via the data network to other equivalent devices and/or other receivers.

9. The screwing device according to claim 6 , wherein the screwing device is configured and embodied to start control programs loaded locally at the screwing device using associated control and regulating parameters from a remote station connected to the data network.

10. A method of operating a screwing device, wherein the screwing device comprises:
a storage container for screws having a screw head, a screw head drive, and a threaded pin,
a robot manipulator having an effector, which is adapted to the screw head and the screw head drive, and is embodied and configured to pick up and handle the screws,
an isolating unit connected to the storage container, the isolating unit comprising an interface at a known position, wherein the screw head of a respective screw isolated from the container is accessible to the effector at the interface, and
a control unit to control or regulate the robot manipulator to pick up the screw head of the respective screw in the effector, wherein the control unit executes a first control program to perform operations of the method comprising:
guiding the effector by the robot manipulator along a predetermined trajectory T 1 having a target orientation O target,T1 (R T1 ) to the screw head of the respective screw provided at the interface, wherein along the trajectory T 1 for locations R T1 of the trajectory T 1 , the target orientation O target,T1 (R T1 ) of the effector is defined; and
beginning at a predefined distance from the screw head of the respective screw, executing force-regulated and/or impedance-regulated and/or admittance-regulated period and closed tilting movements of the effector relative to the target orientation O target,T1 (R T1 ) by the robot manipulator until a predetermined limiting value condition G 1 for a torque acting on the effector and/or a predetermined limiting value condition G 2

Assignees

• Franka Emika Gmbh

Inventors

• Ende Tobias
• Haas Michael
• Golz Saskia
• Parusel Sven
• Haddadin Simon

Classifications

• G05B2219/40087

  Align hand on workpiece to pick up workpiece, peg and hole · CPC title

• B25J9/1679 Primary

  characterised by the tasks executed · CPC title

• G05B2219/45203

  Screwing · CPC title

• G05B2219/45091

  Screwing robot, tighten or loose bolt · CPC title

• G05B2219/40072

  Exert a screwing motion · CPC title