Patent ID: 6985792
Filing Date: 2006-01-10
Classification: G05B

Abstract:
1. A method for automatically correcting systematic errors in measurement machines and in manufacturing machines equipped with a final machine member, comprising: identifying a parametric mathematical model of the machine, initially assigning, to the parameters of said parametric mathematical model, numerical values considered to be close to the actual values, thus obtaining a provisional mathematical model of the machine, performing a plurality of mutually independent experimental distance measurements, within the working field of the machine in various directions, a majority of which are not parallel to the axis of the machine, thus producing experimentally measured distance values, determining possible differences between the experimentally measured distance values and corresponding distance values deduced from said provisional mathematical model, to define a corresponding provisional inaccuracy index of the machine, varying said numerical values assigned to said parameters in the sense of improving the predefined provisional inaccuracy index, to hence obtain a new provisional mathematical model of the machine which is closer to a final mathematical model of the machine, if the improved inaccuracy index so obtained is not satisfactory, proceeding iteratively with new determinations of the differences between the experimentally measured distance values and the corresponding distance values deduced from said provisional mathematical model until said parameter variations do not produce any further significant improvement in said inaccuracy index, to hence obtain the mathematical model of the machine, obtaining from said mathematical model the position errors of the final machine member and, if the machine has rotation freedom degrees of said final member, also its orientation errors, and providing a numerical control system with the error data to execute the correction.