Patent ID: 6618633
Filing Date: 2003-09-09
Classification: B25J,G01B,G05B

Abstract:
A method for calibrating a first co-ordinate frame of an indexing means in a second frame of reference of a sensing means when the sensing means is substantially rigidly attached to the indexing means, including the steps of:measuring first positions of a plurality of first light sources relative to the sensing means, each of which first light sources is remote from the sensing means and is either an active light source or an illuminable reflecting point, with the first positions corresponding to a first absolute position of the indexing means; moving the indexing means; measuring second positions of the plurality of first light sources relative to the sensing means, which second positions correspond to the desired second absolute position of the indexing means; repeating the measurement of and movement from the first to second positions providing at least two sets of measurements of first and second positions corresponding to at least two movements, each of which at least two movements is a known, unique transform; and combining the at least two sets of measurements of first and second positions of the plurality of first light sources relative to the sensing means by a transformation means so as to calibrate for calibrating the first co-ordinate frame in the second frame of reference.