Smart hysteresis compensation of a magneto-elastic force sensor based on Terfenol-D

In this paper a very simple but smart method to compensate the hysteresis of the sensor signal of a force sensor based on the magneto-elastic-effect is introduced. The compensation is tricky because it must meet some stringent requirements. First of all the hysteresis model has to be invertible and the calculation complexity needs to be sufficiently low to be calculated by a DSP in realtime. Another important requirement is that the minor-loops of the hysteresis models are closed to prevent overall signal-drifts. So some hysteresis models known from the literature (e.g. Preisach, Jiles-Atherton, Coleman-Hodgdon) were taken under thorough investigation. After a detailed analyses an adapted version of the Preisach hysteresis model was implemented and results obtained with this adapted model are presented.