Novel dynamic force sensing system using magnetostrictive energy harvester

Dynamic force sensors play a key role in emerging smart technologies that can measure various types of human motions. Magnetostrictive force sensors are the most promising, lightweight, and reliable sensing technologies; however, an in-depth understanding of the sensing mechanism is still lacking. In this study, we focus on magnetic Barkhausen noise (MBN), which is generated by the inverse magnetostriction effect upon impact loading. Further, the stress-induced MBN characteristics of Fe-Co alloy/epoxy composites were investigated using a cyclic compression test. By measuring and analyzing MBN signals in magnetostrictive/epoxy resin composites, it was revealed that the root mean square value of MBN increased linearly with the increase in the stress rate. Additionally, we observed that the MBN outbreaks were affected by the magnetostriction constant. The proposed MBN force sensor system is expected to achieve high sensitivity, wide measurement range, and downsizing.