COMPARATOR PRINCIPLE IN COORDINATE MEASUREMENTS

The error of multicoordinate measurement apparatus caused by the break down of the comparator principle is analyzed. It is shown that, when t he coordinates of a point and the modulus of the displacement vector a re measured, errors proportional to the first power of the carriage-ro tation angle manifest themselves in a different way, and, to completel y describe this error, besides allowing for the shoulder where the Abb e principle breaks down with respect to any scale, one must take into account the displacement of the probe with respect to the point where information is measured along the same scale.