Measurement System for a Magnetostrictive Torque Sensor

The experimental set up for a magnetostrictive sensor made of NiFe thin film electrodeposited on a cylindrical non magnetic 316L stainless steel rod is presented. The sensor operates inside an AC magnetic field generated by an excitation coil. An amplifier is used to ensure saturation levels in the samples' magnetization. The resulting magnetization is picked up by a sensing coil wound around it in the form of a voltage waveform which is in turn being processed by our LabView® based software. The torque is applied by a specially designed apparatus allowing up to 150 Nm. Preliminary results are presented.