Calibration method, calibration system, and program

Patent metadata

Field	Value
Publication number	US-2019047152-A1
Application number	US-201816038554-A
Country	US
Kind code	A1
Filing date	Jul 18, 2018
Priority date	Aug 9, 2017
Publication date	Feb 14, 2019
Grant date	—

Abstract

This method is for calibrating a coordinate system of an image capture device and a coordinate system of a robot arm in a robot system that includes a display device, the image capture device, and the robot arm to which one of the display device and the image capture device is fixed, the robot arm having a drive shaft. The method includes: acquiring first captured image data based on first image data; acquiring second captured image data based on second image data different from the first image data; and calibrating the coordinate system of the image capture device and the coordinate system of the robot arm, using the first captured image data and the second captured image data.

First claim

1 . A method for calibrating a coordinate system of an image capture device and a coordinate system of a robot arm in a robot system that includes a display device, the image capture device, and the robot arm to which one of the display device and the image capture device is fixed, the robot arm having a drive shaft, the method comprising:
causing the display device to display a first image based on first image data; capturing an image of the first image displayed on the display device and acquiring first captured image data, using the image capture device; causing the display device to display a second image based on second image data different from the first image data; capturing an image of the second image displayed on the display device and acquiring second captured image data, using the image capture device; and calibrating the coordinate system of the image capture device and the coordinate system of the robot arm using the first captured image data and the second captured image data.

2 . The calibration method according to claim 1 ,
wherein data indicating a pattern in an image to be displayed or data indicating a brightness of the image to be displayed differs between the first image data and the second image data.

3 . The calibration method according to claim 1 ,
wherein each of the first image data and the second image data is data indicating a pattern in an image to be displayed, and data regarding a color of at least one pixel in the image to be displayed on the display device differs between the first image data and the second image data.

4 . The calibration method according to claim 1 , further comprising:
changing relative positions of the display device and the image capture device using the robot arm, after acquiring the first captured image data, wherein acquiring the second captured image data is performed after changing the relative positions.

5 . The calibration method according to claim 1 ,
wherein, during causing the display device to display the first image and causing the display device to display the second image, in the first image data or the second image data, a size of a pattern in the first image or the second image to be displayed is changed in accordance with coordinates of a leading end of the robot arm.

6 . The calibration method according to claim 1 ,
wherein, during causing the display device to display the first image and causing the display device to display the second image, in the first image data or the second image data, a size of a pattern in the first image or the second image to be displayed is changed in accordance with a distance between the image capture device and the display device.

7 . The calibration method according to claim 1 , further comprising:
changing a relative angle between the display device and the image capture device using the robot arm, after acquiring the first captured image data, wherein at least data indicating a brightness of an image to be displayed differs between the first image data and the second image data.

8 . The calibration method according to claim 1 ,
wherein a relative positional orientation of the image capture device with respect to the display device during acquiring the first captured image data and a relative positional orientation of the image capture device with respect to the display device during acquiring the second captured image data are the same.

9 . The calibration method according to claim 1 ,
wherein the display device includes a sensor for measuring a brightness, and a computing unit configured to change the first image data or the second image data based on a detection value from the sensor, and during causing the display device to display the first image and causing the display device to display the second image, in the first image data or the second image data, a brightness of the first image or the second image to be displayed is changed in accordance with the detection value from the sensor for measuring the brightness.

10 . The calibration method according to claim 1 ,
wherein the display device includes an input unit configured to input information, and a computing unit configured to change the first image data or the second image data based on the input information, and during causing the display device to display the first image and causing the display device to display the second image, in the first image data or the second image data, a size and a brightness of a pattern in the first image or the second image to be displayed are changed in accordance with the input information.

11 . The calibration method according to claim 1 , wherein
the display device and the robot arm are fixed to each other, the display device includes a sensor for measuring an amount of movement, and in the first image data or the second image data, a size of a pattern in the first image or the second image to be displayed is determined based on the amount of movement measured by the sensor.

12 . The calibration method according to claim 1 , wherein
the display device and the robot arm are fixed to each other, the display device includes a sensor for measuring an inclination, and data indicating a brightness of an image to be displayed based on at least one of the first image data and the second image data is determined based on a value of the inclination measured by the sensor.

13 . A method for calibrating a coordinate system of an image capture device and a coordinate system of a robot arm in a robot system that includes a display device, the image capture device, and the robot arm to which one of the display device and the image capture device is fixed, the robot arm having a drive shaft, the method comprising:
causing the display device to display a first image based on first image data; capturing an image of the first image displayed on the display device and acquiring first captured image data, using the image capture device; and calibrating a relative positional relationship between the image capture device and the robot arm, using the first captured image data.

14 . The calibration method according to claim 13 ,
wherein, in the first image data, data indicating a pattern in an image to be displayed or data indicating a brightness of the image to be displayed is determined in accordance with an image-capturing environment.

15 . A non-transitory computer-readable recording medium storing a program for performing a method for calibrating a coordinate system of an image capture device and a coordinate system of a robot arm in a robot system that includes a display device, the image capture device, and the robot arm to which one of the display device and the image capture device is fixed, the robot arm having a drive shaft,
the program for causing a computer to perform operations comprising: causing the display device to display a first image based on first image data; causing the image capture device to capture an image of the first image displayed on the display device to acquire first captured image data; causing the display device to display a second image based on second image data different from the first image data; causing the image capture device to capture an image of the second image displayed on the display device to acquire second captured image data; and calibrating the coordinate system of the image capture device and the coordinate system of the robot arm using the first captured image data and the second captured image data.

16 . The non-transitory computer-readable recording medium storing the program according to cla

Assignees

• Omron Tateisi Electronics Co

Inventors

• Tonogai Norikazu

Classifications

• B25J9/1692 Primary

  Calibration of manipulator · CPC title

• G05B2219/39024

  Calibration of manipulator · CPC title

• B25J9/1671

  characterised by simulation, either to verify existing program or to create and verify new program, CAD/CAM oriented, graphic oriented programming systems · CPC title

• B25J9/1697

  Vision controlled systems · CPC title

• G05B2219/39008

  Fixed camera detects reference pattern held by end effector · CPC title