Patent ID: 11858147
Assignee: KAWASAKI JUKOGYO KABUSHIKI KAISHA
Field: Handling (Mechanical engineering)
Classification: CPC B  H  G | IPC B  H

Claim 3:
4. A substrate transfer robot, comprising:
a robot body comprising:
a hand configured to hold a substrate;
a robotic arm including a turning axis of the hand and configured to displace the hand; and
a photoelectric sensor at a tip-end part of the hand, an ideal optical axis being defined at the hand;

a calibration jig having a target body; and
a controller comprising a processor programmed to:
acquire a reference turning position of the hand at which the turning axis is a turning center so that the ideal optical axis extends in a horizontal first direction;
at the reference turning position, operate the robot body so that a first search is performed in which the target body is detected by the photoelectric sensor while moving the hand in a radial direction centering on the turning axis;
after the first search, operate the robot body to distance the hand from the target body in a horizontal second direction perpendicular to the first direction and to shift the hand in the first direction;
after the hand is shifted in the first direction and at the reference turning position, operate the robot body so that a second search is performed in which the target body is detected by the photoelectric sensor while moving the hand in the radial direction centering on the turning axis;
obtain, as a first detected position, a position of the hand in the horizontal second direction perpendicular to the first direction when the target body is detected by the first search;
obtain, as a second detected position, a position of the hand in the second direction when the target body is detected by the second search; and
detect an inclination of the optical axis from the ideal optical axis based on a difference between the first detected position and the second detected position,

wherein the processor of the controller is programmed to operate the robot body so that (i) the hand is at the same reference turning position for both the first search and the second search and (ii) the ideal optical axis thus extends in the same horizontal first direction for both the first search and the second search, and
wherein the hand is located at a position distanced from the target body in the second direction before each of the first and second searches.