摘要 |
<p>The invention provides machine vision methods and apparatus (10) for determining a calibration relationship between the imaging reference frame of an image acquisition device (16) and the motion reference frame (12) of a moveable object by positioning the object so that a fiducial (14) thereon lies at a first fiducial position in the field of view and recording the corresponding position of the object in the motion reference frame. The object is then repositioned so that the fiducial moves to a second fiducial position in the field of view. Again, the corresponding position of the object in the motion reference frame is recorded. Likewise, the object is moved to a third fiducial position in the field of view, and its corresponding position in the motion reference frame is recorded. A calibration relationship between the motion reference frame of the object and the imaging reference frame of the camera as a function of the first, second and third fiducial position and as a function of the first, second and third object positions.</p> |