ROBOT SYSTEM AND CALIBRATION METHOD OF THE ROBOT SYSTEM

摘要

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.

主权项

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 a observing 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 the three teaching points set within a calibration area, two of the three teaching points are placed on different positions in a same plane normal to an optical axis of the visual sensor, the markers of the two of the three teaching points have the same inclination in relation to the optical axis of the visual sensor, and the marker of one except for the two of the three teaching points has an inclination different from that of the two of the three teaching points.