Prof. Dieter Röss

Die Bürgi Aktivitäten strahlen mittlerweile über Lichtensteig hinaus und werden nicht nur von Historikern wahrgenommen, sondern auch von Natur- und Ingenieurwissenschaftlern, die sich an der Genialität der Ideen von Machertypen wie Bürgi und an deren Umsetzung in Instrumente, Uhren und Globen begeistern. Die Begeisterung oder fast schon die Ehrfurcht wird sichtbar, wenn mit modernen Methoden die historischen Leistungen untersucht werden so wie Bürgis ‘Kunstweg’ in der Sprache der heutigen Mathematik und der Einfluss der Kreuzhemmung von Uhren auf deren Genauigkeit durch Simulationen (Prof. Dieter Röss).


About Prof. Dieter Röss:
Prof. Dieter Röss in late 1960 developed and described the first LASER in Germany and probably in Europe, and a bit later in parallel the first commercial MASER in Europe (installed at the Raisting satellite communication site). He wrote many remarkable articles and the first german textbook on the subject, which is still remembered as a milestone and was very well received at the time.


How only, that such a physicist and father of modern technologies becomes interested in Verge & Foliot Clocks and the corresponding - on a first glance “outdated” - mechanics?


Let’s explain this in his own words:

“Now, why should one try to improve V&F escapements?- My recent interest in the V&F escapement resulted from pure scientific and historical curiosity. Studying escapements in general, I detected that the “horological popes” had overlooked the importance of the drive weight as part of the V&F oscillator, and hence disclaimed it to be a real oscillator. That made me develop a detailed simulation program of the “ideal V&F-oscillator”, that was published.


Further I found no historical source for the claim of miserable accuracy (15 min per day and more). Such a value seemed to me to be completely useless in practice and could not have justified its high cost. So out of historical reason, (and for the fun of experimenting) I built some new turret-clock sized escapements, with modern measuring equipment.  The main question thereby was: what causes the long- and short-term deviations from constant period? (the math model of course delivers constant periods). It is stochastic friction damage under the extreme pressure of a point contact between tooth and pallet. That immediately leads to the logic chain from V&F to cross beat, to anchor and H4, as steps in friction improvement, quite apart from the advantage of coupling to a second “free” oscillator”, as a spring or pendulum.”


F. Heiniger, Jost Bürgi-Kernteam

HSN 2023-1 D Roess Ex.pdf
Adobe Acrobat Dokument 4.4 MB


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