Robot system and robot control method

Patent metadata

Field	Value
Publication number	US-11230004-B2
Application number	US-201916591637-A
Country	US
Kind code	B2
Filing date	Oct 3, 2019
Priority date	Oct 17, 2018
Publication date	Jan 25, 2022
Grant date	Jan 25, 2022

Abstract

A robot system includes circuitry. The circuitry may be configured to acquire teaching position data including a plurality of teaching positions arranged in time series based on the demonstration data of the operator. The circuitry may be further configured to generate thinned position data obtained by removing at least one of the teaching positions from the teaching position data. The circuitry may be further configured to generate a position command based on the thinned position data. The circuitry may be further configured to operate the work robot based on the position command.

First claim

What is claimed is:

1. A robot system comprising circuitry configured to:
acquire teaching position data including a plurality of teaching positions arranged in time series based on demonstration data of an operator;
generate thinned position data obtained by removing at least one of the teaching positions from the teaching position data;
generate a position command based on the thinned position data;
acquire teaching force data including a plurality of teaching forces arranged in time series based on the demonstration data of the operator;
generate thinned force data obtained by removing at least one of the teaching forces from the teaching force data;
generate a force command based on the thinned force data; and
operate a work robot based on the position command and the force command.

2. The robot system according to claim 1 , wherein
the teaching positions include two teaching positions having different influence on a movement of the robot, and
the circuitry is further configured to remove, from the teaching position data, one of the two teaching positions having a smaller influence on the movement of the robot.

3. The robot system according to claim 2 , wherein the influence of the teaching position includes a change in a motion of the robot in accordance with the teaching position data by removing the teaching position from the teaching position data.

4. The robot system according to claim 3 , wherein the circuitry is further configured to generate the thinned position data based on an amount of offset between a teaching position and a reference line connecting teaching positions prior to and posterior to the teaching position.

5. The robot system according to claim 1 , wherein
the teaching forces include two teaching forces having different influence on a working force applied to a work object by the robot, and
the circuitry is further configured to remove, from the teaching force data, one of the two teaching forces having a smaller influence on the working force applied to the work object by the robot.

6. The robot system according to claim 1 , wherein the circuitry is further configured to:
acquire measurement data of a working force applied to a work object by the robot operated based on the position command and the force command; and
correct the position command so as to reduce a difference between the measurement data and the teaching force data.

7. The robot system according to claim 6 , wherein the circuitry is further configured to:
correct the teaching position data so as to reduce the difference between the measurement data and the teaching force data;
remove at least one of the teaching positions from the corrected teaching position data to update the thinned position data; and
update the position command based on the updated thinned position data.

8. The robot system according to claim 6 , wherein the circuitry is further configured to repeat a sequence of operations comprising:
an operation of the robot based on the position command and the force command;
an acquisition of the measurement data of the working force applied to the work object by the robot, and a correction of the position command until an amount of offset between the measurement data and the teaching force data satisfies an allowable condition.

9. The robot system according to claim 1 , wherein the circuitry is further configured to:
correct the teaching position data so as to reduce a positional fluctuation of the robot before applying a working force to a work object; and
remove at least one of the teaching positions from the corrected teaching position data to generate the thinned position data.

10. The robot system according to claim 1 , wherein the circuitry is further configured to correct a control target position of the robot during an operation of the robot so as to reduce a difference between a force applied to a work object by the robot and the force command.

11. The robot system according to claim 1 further comprising:
a demonstration tool for performing motion teaching by demonstration; and
a teaching motion detection unit configured to detect position of the demonstration tool,
wherein the circuitry is further configured to acquire the teaching position data based on the position of the demonstration tool detected by the teaching motion detection unit.

12. The robot system according to claim 11 , wherein the teaching motion detection unit comprises:
a passive articulated arm configured to move according to the position of the demonstration tool, the articulated arm having a plurality of joints; and
a plurality of angle sensors configured to detect motion angles of the joints respectively, and
wherein the circuitry is configured to acquire information on the motion angles of the joints from the angle sensors so as to calculate the teaching position based on the motion angles.

13. The robot system according to claim 12 , wherein the teaching motion detection unit further comprises a force sensor configured to detect a force acting on the demonstration tool, and
wherein the circuitry is further configured to acquire teaching force data based on the force detected by the force sensor.

14. A robot control method comprising:
acquiring teaching position data including a plurality of teaching positions arranged in time series based on demonstration data of an operator;
generating thinned position data obtained by removing at least one of the teaching positions from the teaching position data;
generating a position command based on the thinned position data;
acquiring teaching force data including a plurality of teaching forces arranged in time series based on the demonstration data of the operator;
generating thinned force data obtained by removing at least one of the teaching forces from the teaching force data;
generating a force command based on the thinned force data; and
operating a work robot based on the position command and the force command.

15. A non-transitory memory device having instructions stored thereon that, in response to execution by a processing device, cause the processing device to perform operations comprising:
acquiring teaching position data including a plurality of teaching positions arranged in time series based on demonstration data of an operator;
generating thinned position data obtained by removing at least one of the teaching positions from the teaching position data;
generating a position command based on the thinned position data;
acquiring teaching force data including a plurality of teaching forces arranged in time series based on the demonstration data of the operator;
generating thinned force data obtained by removing at least one of the teaching forces from the teaching force data;
generating a force command based on the thinned force data; and
operating a work robot based on the position command and the force command.

16. A robot system comprising circuitry configured to:
acquire teaching position data including a plurality of teaching positions arranged in time series based on demonstration data of an operator;
generate thinned position data obtained by removing at least one of the teaching positions from the teaching position data, wherein the thinned position data is generated based on an amount of offset between a teaching position and a reference line connecting teaching positions prior to and posterior to the teaching position;
generate a position command based on the thinned position data; and
operate a work robot based on the position command.

17. The robot system accor

Assignees

• Yaskawa Electric Corp

Inventors

• Iwasa Toshihiro
• Nagai Ryoichi
• Mullennix Nathanael
• Ando Shingo

Classifications

• G05B2219/36489

  Position and force · CPC title

• B25J9/1656

  characterised by programming, planning systems for manipulators · CPC title

• B25J9/0081 Primary

  with leader teach-in means · CPC title

• B25J13/085

  Force or torque sensors (B25J13/082, B25J13/084 take precedence) · CPC title

• G05B19/42

  Recording and playback systems, i.e. in which the program is recorded from a cycle of operations, e.g. the cycle of operations being manually controlled, after which this record is played back on the same machine · CPC title