Non-invasive magnetostrictive sensor

摘要

A magnetostrictive sensor (200) to sense force (212) or torque applied to a structural element (204) to which the magnetostrictive sensor is non-invasively attached by a fixed, intimate contact therewith. The sensor consists of a magnetostrictive layer (210) in intimate contact with a coil (206) excited source of magnetic flux. A force or torque applied to the structural element produces a stress transferred to the magnetostrictive layer, thereby varying the magnetic permeability of the magnetostrictive layer. The change in the magnetic flux (224) produces a change in the inductance and impedance of the coil, and thereby a detectable change in the voltage V' s across the coil.