Non-contact detection of magnetoelastic bilayer position sensors

The paper concerns the contactless position sensing by the help of magnetoelastic bilayers, a novel multifunctional mechanic sensor element. The bilayer is sensitive to bending or temperature change both yielding a change of its magnetic permeability as a basis for signal detection. In this work, the bilayer is fixed at one end while the other end is displaced. The position signal is evaluated from the voltage signal of a pick-up coil placed in a distance to the bilayer. The possibility to improve the procedure by the help of electric resonance effects is shown. A detection range of 30 mm has effectively been established.