Development and Application of Super-Small Size Strain History Recorder Based on Rainflow Method

Abstract

A very small strain history recorder based on the rainflow method has been developed and was named the Mini Rainflow Corder. The Mini Rainflow Corder is installed with IC chips containing the Rainflow algorithm software, an amplifier circuit, automatic bridge balance, a standard small size memory card in which the decomposed strain history data is stored and batteries. The data obtained under service loading can be easily retrieved by a personal or laptop computer from the memory card. The performance of the Mini Rainflow Corder was tested using the fatigue testing machine in laboratory, and also by the specially designed cantilever type cyclic loading testing machine. The accuracy of data acquisition, reliability at low and high temperatures, and shock resistance were also examined. The advantage of the developed recorder in application to rotating machine parts without a slip ring is emphasized. The application to car wheels was demonstrated.