Magnetostrictive-based Jerk Sensor: Experimental characterization and analytical estimation of sensitivity

In this study, we explore the utilization of the magnetostrictive transduction principle for the creation of a single-axis inertial sensor. A prototype sensor is constructed using magnetostrictive Terfenol-D. We characterize the accelerometer's sensitivity through two independent methodologies, yielding results that align with finite-element analysis. Notably, the sensor exhibits an inherent response to jerk—the time derivative of acceleration—resulting in an accelerometer sensitivity that maintains a +6 dB/octave slope relative to frequency, up to the sensor's first resonance. This design features a low output impedance, akin to moving-coil geophones, thus eliminating the necessity for intermediary buffering electronics. Moreover, we present a first-order analytical method for estimating the maximum achievable sensitivity of the sensor and thereby offering an efficient tool applicable to a broader spectrum of magnetostrictive-based sensor designs.