Counting Procedures Option
As well as harmonic analysis by means of Fourier transform, counting procedures have proved to be an important tool for examining signals, in particular for load-time functions. The counting procedure is based on the search for specific events in the load-time function, e.g. exceeding a certain load level, or a load alternation of a certain amplitude. For this purpose, the range of values of the load-time function is divided into discrete ranges known as classes. Each event found is assigned to a class and counted in this class.
The result shows a frequency for each class. The Counting Procedures Option provides you with a broad spectrum of counting procedures. The bases for the implementation are the DIN 45667 standard and the more recent Rainflow Procedure. The DIN 45667 standard dates back to 1969 and is geared toward the technical counting devices available at the time. The Rainflow procedure has mainly replaced the counting procedures described in DIN 45667. Therefore, only those DIN 45667 procedures were implemented for which the Rainflow procedure does not offer an equivalent. In addition, the Rainflow procedure is better at addressing fatigue strength testing requirements. The Rainflow procedure provides better results for this purpose.
References
[1] DIN 45667 (1970). Klassierverfahren für das Erfassen regelloser Schwingungen (Counting procedures for determining random oscillations). Beuth Verlag
[2] de Jonge, J.B. (1980). Counting Methods for the Analysis of Load Time Histories. NLR Memorandum SB-80-106 U
[3] Fraunhofer-Institut für Betriebsfestigkeit LBF (Fraunhofer-Institute for Structural Durability LBF), Darmstadt. Hinweise zur Anwendung von Zählverfahren im Rahmen von Betriebsfestigkeitsuntersuchungen (Tips on using counting procedures as part of structural durability testing). www.simtop.fhg.de/cgi-bin/rmcat?1000kl03
[4] ASTM E1049-85(2017)..Standard Practices for Cycle Counting in Fatigue Analysis.STM International, West Conshohocken, PA, 2017