Image measurement apparatus, image measurement method and image measurement program

摘要

Two-dimensional measurement is allowed with a small error even in the case where a difference occurs between a measurement plane for a workpiece and a plane with calibrated external parameters. When the workpiece 2 is gripped by a holding device 3, an image measurement apparatus 1 calculates the difference between the calibration plane 17 where the external parameters are calibrated and the measurement plane 20 for the workpiece 2. The image measurement apparatus 1 corrects the external parameters such that the calibration plane 17 coincides with the measurement plane 20, and two-dimensionally measures the workpiece 2 using the corrected external parameters.

主权项

1. An image measurement apparatus, comprising:
a first camera that takes an image of a workpiece held by a holding device; a detecting device provided on the holding device that detects a position and/or a posture of a measurement plane for the workpiece held by the holding device; and a control unit that stores external parameters of the first camera and a position and/or a posture of a calibration plane where the external parameters are calibrated, stores the position and/or the posture of the measurement plane for the workpiece detected by the detecting device while the workpiece is held by the holding device, corrects the external parameters based on a detected value by the detecting device such that the positions and/or the postures of the measurement plane and the calibration plane coincide with each other, and measures a two-dimensional position and/or a posture of the workpiece held by the holding device from the image taken by the first camera using the corrected external parameters.