PTB at the Frankfurt Microtecnic

"Meet the World" will be the motto of this year's Microtecnic which will be held in Frankfurt from October 15 to 18 and will make the city the meeting place of international experts from the fields of mechanical production metrology and quality assurance.

Microtecnic carries on a successful tradition - since it was first held in 1967, Microtecnic's importance as a fair for mechanical production metrology and quality assurance has been constantly gaining in importance -, and it will profit from its transfer to another place and give new impulses. It is not least because Frankfurt is considered throughout the world to be one of the hearts of the capital market and of trade, because Frankfurt is situated in the centre of a unified Europe and because its central fairgrounds are an ideal platform to address an international public, to make new contacts and to keep up existing relations, that Frankfurt has been chosen as the new place where to hold Microtecnic '96.

The Physikalisch-Technische Bundesanstalt (PTB), too, will make use of Microtecnic's new location to present its work. Members of its staff will offer information on the tasks and organization of PTB and of the Deutscher Kalibrierdienst (DKD, German Calibration Service), answer questions concerning the topics of accreditation, mutual recognition of calibrations, tests and certifications etc., and be available for discussions of technical problems concerning the calibration of measuring equipment.

As an example of latest results of its research work, the PTB will present a selection of standards developed at the PTB for the calibration of coordinate measuring machines, and a new method which will allow the accuracy of measurement of coordinate measuring machines to be estimated for any calibration tasks (description below).

New method which allows the accuracy of measurement of coordinate measuring machines to be estimated for any measurement tasks

The result of a measurement is informative only if the respective accuracy of measurement (correct: "uncertainty of measurement") is known. This is not difficult in the case of measuring devices which always measure the same product in an identical way, provided that a standard is available which is known with sufficient accuracy. Things become difficult when universal measuring devices are concerned, coordinate measuring machines, for example: An almost infinitely great number of different measurement tasks can be carried out on such devices.

Until a few years ago there was no possibility of estimating the accuracy of measurement of coordinate measuring machines for any measurement task desired. The PTB has now developed a method which makes such an estimation possible. The method is based on the principle that simple standards are measured by means of the instrument to be examined. The characteristic error components are then determined from these measurements using a special analyzing software. These error components are used to generate a computer model, the "virtual coordinate measuring machine", whose measurement errors are similar to those of the real instrument. This virtual instrument allows any measurement tasks to be simulated with the aid of a computer and the accuracy of the results analyzed and optimized.

This method and its software components for the analysis of instrument-related errors and for the simulation of measurement tasks will be presented at the PTB's stand on the occasion of Microtecnic '96.