The dimensions of technical products are often of major importance for t heir proper functioning. Dimensional tolerances define how much the true dimensions may deviate from the aimed dimensions. Dimensional quality c ontrol ensures that the dimensional properties of the product comply wit h the tolerances. For single and non-complex products instruments like v ernier calipers and micrometer screw gauges can be used, while for more complex inspection tasks and series measurements usually coordinate meas uring machines (CMMs) are used.Because measurement devices also show measurement errors, a measurement result will never be exact. This means there will always be a measurement uncertainty that should be take n into account while evaluating conformance of products to tolerances. I f measurement uncertainty is neglected, this can result in false rejecti on or false acceptance of products, with possibly far-reaching consequen ces. Reliable measurement uncertainties are indispensable for unambiguou s evaluation of tolerances.Measurement uncertainty determination for coordinate measuring machines is difficult because of the many unce rtainty contributors (CMM hardware errors, temperature, measurement stra tegy, ...) that are involved. Therefore conventional uncertainty calcula tion methods, based on analytical propagation of standard uncertainties, can not be applied. Measurement uncertainty determination based on Mont e Carlo simulations is a valuable alternative to conventional uncertaint y calculation methods. These methods can cope much better with the compl exity of CMM measurements.This thesis describes four contributio ns to the determination of measurement uncertainties for feature measure ments on CMMs by means of Monte Carlo methods:
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