Robot system and calibration method of the robot system
First Claim
1. A robot system comprising:
- a robot body configured to operate a work;
a visual sensor; and
a control apparatus configured to control a position and an orientation of the robot body, and to calculate a position and an orientation of the work using a measured value by the visual sensor, wherein,when observation of a marker by the visual sensor is performed for a calibration between a robot coordinate system fixed to the robot body and a vision coordinate system fixed to the visual sensor, a calibration value is calculated based on a position of the robot body in the robot coordinate system, and a position of the marker in the vision coordinate system for at least three teaching points set within a calibration area, two of the three teaching points are placed on different positions in a plane A of a finite size normal to an optical axis of the visual sensor, wherein the marker at two of the three teaching points has the same inclination in relation to the optical axis of the visual sensor, and wherein the marker at the teaching point other than the two of the three teaching points has an inclination different from that of the two of the three teaching points and crosses the plane A.
1 Assignment
0 Petitions
Accused Products
Abstract
A control apparatus calculates a calibration value based on a position in the robot coordinate system 41 and a position in the vision coordinate system 42, for at least three teaching points set within a calibration area. Markers 21 of two of the three teaching points have the same inclination in relation to an optical axis of a camera 3 as a visual sensor, and the two points are placed on different positions of the same plane normal to the optical axis. The remaining one of the three teaching points other than the two points is set such that the inclination of the marker 21 in relation to the optical axis is different from that of the two points. As a result, influence of a large quantization error in the optical axis direction as a measurement error of the camera 3 can be reduced.
-
Citations
13 Claims
-
1. A robot system comprising:
-
a robot body configured to operate a work; a visual sensor; and a control apparatus configured to control a position and an orientation of the robot body, and to calculate a position and an orientation of the work using a measured value by the visual sensor, wherein, when observation of a marker by the visual sensor is performed for a calibration between a robot coordinate system fixed to the robot body and a vision coordinate system fixed to the visual sensor, a calibration value is calculated based on a position of the robot body in the robot coordinate system, and a position of the marker in the vision coordinate system for at least three teaching points set within a calibration area, two of the three teaching points are placed on different positions in a plane A of a finite size normal to an optical axis of the visual sensor, wherein the marker at two of the three teaching points has the same inclination in relation to the optical axis of the visual sensor, and wherein the marker at the teaching point other than the two of the three teaching points has an inclination different from that of the two of the three teaching points and crosses the plane A. - View Dependent Claims (2, 3, 4, 5, 6)
-
-
7. A calibration method of a robot system, wherein
the robot system comprises: -
a robot body configured to operate a work; a visual sensor; and a control apparatus configured to control a position and an orientation of the robot body, and to calculate a position and an orientation of the work using a measured value by the visual sensor, wherein the calibration method is performed for a calibration between a robot coordinate system fixed to the robot body and a vision coordinate system fixed to the visual sensor, and the calibration method comprises operating, by the control apparatus, the robot body to obtain three teaching points within a calibration area; and observing a marker by the visual sensor, to calculate a calibration value based on a position of the robot body in the robot coordinate system, and a position of the marker in the vision coordinate system for at least the three teaching points, wherein two of the three teaching points are placed on different positions in a plane A of a finite size normal to an optical axis of the visual sensor, wherein the marker at two of the three teaching points has the same inclination in relation to the optical axis of the visual sensor, and wherein the marker at the teaching point other than the two of the three teaching points has an inclination different from that of the two of the three teaching points and crosses the plane A. - View Dependent Claims (8, 9, 10, 11, 12, 13)
-
Specification