Automatic calibration for a robot optical sensor

Patent metadata

Field	Value
Publication number	US-2020282575-A1
Application number	US-201916293584-A
Country	US
Kind code	A1
Filing date	Mar 5, 2019
Priority date	Mar 5, 2019
Publication date	Sep 10, 2020
Grant date	—

Abstract

Systems and methods are provided for automatic intrinsic and extrinsic calibration for a robot optical sensor. An implementation includes an optical sensor; a robot arm; a calibration chart; one or more processors; and a memory storing instructions that cause the one or more processors to perform operations that includes: determining a set of poses for calibrating the first optical sensor; generating, based at least on the set of poses, pose data comprising three dimensional (3D) position and orientation data; moving, based at least on the pose data, the robot arm into a plurality of poses; at each pose of the plurality of poses, capturing a set of images of the calibration chart with the first optical sensor and recording a pose; calculating intrinsic calibration parameters, based at least on the set of captured images; and calculating extrinsic calibration parameters, based at least on the set of captured images.

First claim

What is claimed is:

1 . A system for automatic calibration of a robot optical sensor, the system comprising:
an optical sensor; a robot arm; a calibration chart; one or more processors; and a memory storing instructions, that when executed by the one or more processors, cause the one or more processors to perform operations comprising:
determining a set of poses for calibrating the optical sensor;
generating, based at least on the set of poses, pose data comprising three dimensional (3D) position and orientation data;
moving, based at least on the pose data, the robot arm into a plurality of poses;
at each pose of the plurality of poses, capturing a set of images of the calibration chart with the optical sensor;
calculating intrinsic calibration parameters, based at least on the set of captured images; and
calculating extrinsic calibration parameters, based at least on the set of captured images.

2 . The system of claim 1 wherein the operations further comprise:
prior to calculating the extrinsic calibration parameters, applying the intrinsic calibration parameters to the set of captured images.

3 . The system of claim 1 wherein the operations further comprise:
determining whether a pose in the set of poses is reachable; and
based at least on the pose not being reachable, rejecting the pose.

4 . The system of claim 1 wherein the calibration chart is attached to an end effector of the robot arm, and wherein the optical sensor is mounted on a body of the robot.

5 . The system of claim 1 wherein the optical sensor is mounted on the robot arm.

6 . The system of claim 1 wherein the operations further comprise:
determining a trigger event for calibrating the optical sensor; and
wherein determining the set of poses for calibrating the optical sensor comprises:
based at least on the trigger event, determining the set of poses for calibrating the optical sensor.

7 . The system of claim 6 wherein the optical sensor is a first optical sensor, and wherein the system further comprises:
a second optical sensor; and
wherein determining the trigger event comprises comparing images captured with the first optical sensor with images captured with the second optical sensor.

8 . A method of automatic calibration of a robot optical sensor, the method comprising:
determining a set of poses for calibrating an optical sensor; generating, based at least on the set of poses, pose data comprising three dimensional (3D) position and orientation data; moving, based at least on the pose data, a robot arm into a plurality of poses; at each pose of the plurality of poses, capturing a set of images of a calibration chart with the optical sensor; calculating intrinsic calibration parameters, based at least on the set of captured images; and calculating extrinsic calibration parameters, based at least on the set of captured images.

9 . The method of claim 8 further comprising:
prior to calculating the extrinsic calibration parameters, applying the intrinsic calibration parameters to the set of captured images.

10 . The method of claim 8 further comprising:
determining whether a pose in the set of poses is reachable; and
based at least on the pose not being reachable, rejecting the pose.

11 . The method of claim 8 wherein the calibration chart is attached to an end effector of the robot arm, and wherein the optical sensor is mounted on a body of the robot.

12 . The method of claim 8 wherein the optical sensor is mounted on the robot arm.

13 . The method of claim 8 further comprising:
determining a trigger event for calibrating the optical sensor; and
wherein determining the set of poses for calibrating the optical sensor comprises:
based at least on the trigger event, determining the set of poses for calibrating the optical sensor.

14 . The method of claim 13 wherein the optical sensor is a first optical sensor, and wherein determining the trigger event comprises:
comparing images captured with the first optical sensor with images captured with a second optical sensor.

15 . A computer program product, comprising a computer usable medium having a computer readable program code embodied therein, the computer readable program code adapted to be executed to implement a method for automatically calibrating a robot optical sensor, the method comprising:
determining a set of poses for calibrating an optical sensor; generating, based at least on the set of poses, pose data comprising three dimensional (3D) position and orientation data; moving, based at least on the pose data, a robot arm into a plurality of poses; at each pose of the plurality of poses, capturing a set of images of a calibration chart with the optical sensor; calculating intrinsic calibration parameters, based at least on the set of captured images; and calculating extrinsic calibration parameters, based at least on the set of captured images.

16 . The computer program product of claim 15 wherein the operations further comprise:
prior to calculating the extrinsic calibration parameters, applying the intrinsic calibration parameters to the set of captured images.

17 . The computer program product of claim 15 wherein the operations further comprise:
determining whether a pose in the set of poses is reachable; and
based at least on the pose not being reachable, rejecting the pose.

18 . The computer program product of claim 15 wherein the calibration chart is attached to an end effector of the robot arm, and wherein the optical sensor is mounted on a body of the robot.

19 . The computer program product of claim 15 wherein the optical sensor is mounted on the robot arm.

20 . The computer program product of claim 15 wherein the optical sensor is a first optical sensor, and wherein the operations further comprise:
determining a trigger event for calibrating the first optical sensor, wherein determining the trigger event comprises:
comparing images captured with the first optical sensor with images captured with a second optical sensor; and

wherein determining the set of poses for calibrating the first optical sensor comprises:
based at least on the trigger event, determining the set of poses for calibrating the first optical sensor.

Assignees

• Boeing Co

Inventors

• Haeusler Phillip
• Cochrane Jason John

Classifications

• H10P72/0606

  Position monitoring, e.g. misposition detection or presence detection · CPC title

• B25J9/1692 Primary

  Calibration of manipulator · CPC title

• B25J9/1602

  characterised by the control system, structure, architecture · CPC title

• H04N13/246 Primary

  Calibration of cameras · CPC title

• B25J9/1697

  Vision controlled systems · CPC title