Abstract
Virtual CMM is an estimation method of uncertainty in coordinate metrology by computer simulation that is proposed by PTB (National Metrology Institute in Germany). The Virtual CMM helps estimating complex uncertainty of measurement using CMM which is called task specific uncertainty. Simulation result must be confirmed by comparing with other certain value. We report the comparison result of the simulation and real measurement about calibrated cylinder gauge. It was confirmed that the estimated uncertainties conform to actually measured deviations. Validity of the simulation method was considered to be verified.