Calibration method for a visual sensor

• US 5,329,469 A
• Filed: 01/24/1992
• Issued: 07/12/1994
• Est. Priority Date: 05/30/1990
• Status: Expired due to Term

• Current Assignee: Fanuc Ltd (Fanuc Corporation)
• Original Assignee: Fanuc Ltd (Fanuc Corporation)
• Inventors: Watanabe, Atsushi
• Primary Examiner(s): Harvey, Jack B.
• Assistant Examiner(s): Wachsman, Hal D.
• Application Number:
  US07/820,588
• Time in Patent Office: 900 Days
• Field of Search: 364/571.01, 364/571.02, 364/571.04, 364/571.05, 364/571.07, 364/571.08, 901/47, 395/89, 395/94, 358/107, 358/93, 358/101
• US Class Current: 700/259
• CPC Class Codes: B25J 9/1697 Vision controlled systems
• CPC Class Codes: G05B 2219/39008 Fixed camera detects reference pattern held by end effector
• CPC Class Codes: G06V 10/147 Details of sensors, e.g. sensor lenses fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19
• CPC Class Codes: G06V 10/245 by locating a pattern; Special marks for positioning

Abstract

A visual sensor calibration method of calibrating of a visual sensor in a robot system. A pattern plate is provided on an arm of a robot, and the calibration pattern data (CPDr) of the pattern plate on robot'"'"'s base coordinates is sent from a robot controller to a visual sensor controller. The visual sensor controller picks up an image of the pattern plate by a camera to obtain calibration pattern data (CPDc). The calibration data (CD) is obtained from the calibration pattern data (CPDr) and the calibration pattern data (CPDc), to thereby calibrate the visual sensor.

Claims

1. A visual sensor calibration method of calibrating a visual sensor in a robot system comprising the steps of:

providing a pattern plate including a plurality of dots, for obtaining a calibration, on an arm of a robot;

obtaining, using a robot controller, a first calibration pattern data of said pattern plate at a position of said pattern plate on said robot arm, said first calibration pattern data being coordinate positions of each of said plurality of dots in said pattern plate;

sending said first calibration pattern data of said pattern plate from said robot controller to a visual sensor controller;

obtaining, using said visual sensor controller, a second calibration pattern data from an image of said pattern plate, said second calibration pattern data being coordinate positions of each of said plurality of dots in said image of said pattern plate; and

obtaining, using said visual sensor controller, calibration data from said first calibration pattern data and said second calibration pattern data, to thereby calibrate a visual sensor.

2. The visual sensor calibration method according to claim 1, further including the step of providing a camera to generate said image of said pattern plate for obtaining said second calibration pattern data.

3. The visual sensor calibration method according to claim 1, further including the step of obtaining said second calibration pattern data by a laser length measuring instrument.

4. The visual sensor calibration method according to claim 1, further including the step of obtaining said second calibration pattern data by a plurality of cameras from one pattern plate of said robot, to thereby calibrate each of said plurality of cameras.

5. The visual sensor calibration method according to claim 1, further including the step of obtaining said second calibration pattern data for a plurality of cameras from pattern plates of a plurality of robots, to thereby carry out a calibration.

6. The visual sensor calibration method according to claim 1, further including the step of providing said pattern plate including one dot pattern as an origin and a plurality of dot patterns arranged in a square shape.

7. The visual sensor calibration method according to claim 1, further including the step of providing said calibration data as matrix data.