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Production sequence of Si-spheres and interferometrical determination of the sphere volume

Automation and modernisation of the tactile gauge block measuring station 1 m comparator


For several decades, the measuring station for the calibration of gauge blocks via a mechanical comparison measurement up to 1 m in length [1] has been performing its service with only a few changes to hardware and software. The strength to be retained despite the age lies in the possibility of still being able to offer attractively low measurement uncertainties for customers with less time expenditure than with highly accurate interferometric calibrations.

After such a long period of operation, there is a risk that maintenance and repair work can no longer be carried out quickly and economically. In case of failure, the calibration business would come to a standstill. The efforts to successively prepare all service measuring stations for gauge block calibrations for the future creation of digital calibration certificates are also severely limited by outdated software. In order to be able to continue to reliably offer calibration services with the so-called 1 m comparator, a fundamental modernisation was tackled within the scope of a bachelor thesis [2].

The objective was to renew the outdated software and also to design a digital control of the measuring station. The existing control system is a control panel that operates various electronic components in the comparator housing. The renewal of the measuring programme takes place under consideration of criteria of modern software, which should guarantee maintainability and expandability in the future. Furthermore, components of the newly developed implementation can be used at other measuring stations in order to keep further programming efforts as low as possible.

The implementation is carried out in several stages. In the first stage, the measurement programme was replicated to such an extent that the existing functionalities of the previous software were taken over and a contemporary and future-proof replacement was created. In the second - currently ongoing - stage, the control desk, which can no longer be replaced in the event of defects, is being digitised, thus creating a future fail-safe. The digital control option of the measuring station will then not only offer a secure operational capability, but will also enable automation in the third stage, which is still to be carried out.

Gauge block measuring station 1 m comparator


[1] E. Potulski, „Ein-Meter-Endmaßkomparator“, Optische und optoelektronische Meßtechnik 1, S. 43-45, 1986
[2] T. Gersdorf, „Modernisierung eines Mess- und Auswerteprogramms eines taktilen Längenkomparators“, Bachelorarbeit, Ostfalia – Hochschule für angewandte Wissenschaften, 2022  





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