| Zugriffsnummer | 23912 |
| Dokumenttyp | Konferenzartikel |
| Sprache | Englisch |
| Titel | Fabrication and measurement development for precise test masses for the MICROSCOPE space project |
| Autor(in); Institution |
Hagedorn, Daniel; 5.5, Wissenschaftlicher Gerätebau, PTB-Braunschweig
Heyne, Heinz-Peter; 5.5, Wissenschaftlicher Gerätebau, PTB-Braunschweig
Reimann, Helge; 5.3, Koordinatenmesstechnik, PTB-Braunschweig
Neugebauer, Michael; 5.3, Koordinatenmesstechnik, PTB-Braunschweig
Grüner, Sven; 5.5, Wissenschaftlicher Gerätebau, PTB-Braunschweig
Metschke, Stephan; 5.5, Wissenschaftlicher Gerätebau, PTB-Braunschweig
Löffler, Frank; 5.5, Wissenschaftlicher Gerätebau, PTB-Braunschweig
|
| Quelle/Jahr | Proceedings of the 9th international conference of the European Society for Precision Engineering and Nanotechnology : June 2nd - June 5th 2009, San Sebastian, Spain: 1 (2009), 29 - 32 |
| Herausgeber(in) |
Van Brussel, Hendrik
|
| ISBN | 978-0-9553082-6-0 |
| Verlag | Bedford: Euspen |
| Konferenzangaben | 9th International conference of the European Society for Precision Engineering and Nanotechnology (euspen), San Sebastian, 02-05, June, 2009, Spain |
| Zusammenfassung | MICROSCOPE ((MICRO-Satellite à traînée Compensée pour l'Observation du Principe d'Equivalence) is an international project for validation of the equivalence principle (EP). In the frame of this project, which is part of the CNES MYRIADE series (project partners are among others CNES, ONERA, DLR, ZARM), it is the task of the Physikalisch-Technische Bundesanstalt (PTB) to develop a course of fabrication to manufacture test masses (TM) for the differential accelerometers to be used in earth’s orbit by the year 2013 and to manufacture these TMs eventually. The experiment is set to detect any violation of the EP with a precision of 10-15. On board the satellite two differential accelerometers, each equipped with an inner and an outer TM, will be used to validate the EP. Both inner TMs and one outer TM will consist of the platinum alloy PtRh10, one outer TM will be made of the Titanium alloy TiAl6V4. While the heterogeneously equipped accelerometer is the instrument to detect a possible violation of the EP, the accelerometer holding two PtRh10 TMs serves as reference. Both TMs have the form of a hollow cylinder with four flats at the lateral surface at 90° intervals and six countersinks at each face at 60° intervals. The outer TM, e.g., has the length of about 80 mm, an outer diameter of about 70 mm and an inner diameter of about 60 mm. The precision of such parameters as dimensions, parallelism, planarity, concentricity, and perpendicularity are all in the range of one micrometer and below. Average roughness is smaller than 0.2 μm, which is, especially with respect to the soft and ductile Pt-alloy, a huge challenge. To achieve such high precision, using a turning process due to the form requirements mentioned above, it is necessary to integrate the measurement instrumentation into the precision machining station (Benzinger TNI preciline). Once the fabrication has begun, we are unable to detach the workpiece and perform external measurements due to the fact that the positional error after re-mount would be greater than the gain of accuracy achieved by an unquestionably more precise ex-situ measurement. Several independent in-situ measurement setups have been integrated into the machining station. One of these, a tactile sensor integrated into the machine’s CNC control unit, is used to measure fabrication progress. As such a sensor is usually specified with an accuracy of about 5 μm, we have developed an evaluation routine, which detects faulty values. To determine the diameter, a best fit circle based on these measurements is derived. To obtain knowledge of the whole cylinder’s form, several such best fit circles are measured over the length of the workpiece. Any deviations are corrected in the following fabrication step. After completion external measurements are performed using the form and size measuring instrument MFU110WP and the micro coordinate measuring machine F25. |
Zitierung
Hagedorn, D., Heyne, H.-P., Reimann, H., Neugebauer, M., Grüner, S., Metschke, S., & Löffler, F. (2009). Fabrication and measurement development for precise test masses for the MICROSCOPE space project. 9th International conference of the European Society for Precision Engineering and Nanotechnology (euspen), San Sebastian, 02-05, June, 2009, Spain.