Hysteresis Reduction Effect of the Cross-Shaking Technique Applied to Magnetostrictive Torque Sensors

A new method for reducing hysteresis is proposed for magnetic head type torque sensors based on the magnetostrictive effect. This method adopts magnetic shaking, in which the shaking field is applied perpendicularly to the exciting field. The hysteresis and sensitivity of a quench-hardened steel shaft (SCM415) 25 mm in diameter subjected to torques ranging from ¿490 N-m to 490 N-m were measured. The hysteresis was reduced by a factor of 10 and the sensitivity was increased by a factor of 2 for an exciting frequency of 10 kHz and shaking frequency of 1 kHz. The relationship of the shaking frequency and the shaking effect to the total power consumption is also discussed.