The roundness deviation measurement with CMM

In the paper, the recommendations on the parameters of a circle measurement with CMM (Coordinate Measuring Machine) are described. The method of uncertainty estimation for the measured circle has been presented, too. The influence of the parameters of measured detail underwent discussion, like the type of form deviation and dimensional tolerances, as well as influence of the measurement method, particularly, number of probing points, CMM permissible error and fitting element type. The simulations and experimental measurement proved that the minimal number of probing points is not recommended. On the other hand, in the touch-trigger measurement, too large number of points does not increase the accuracy of measurement. As a result, the recommendations on the probe points number and CMM accuracy have been presented.