Real time measurement of instantaneous torque by magnetostrictive sensor

A novel torque measurement system has been developed using a magnetostrictive sensor and a digital sensor processing technique. This system contains a miniature magnetostrictive sensor, a digital signal processor (DSP), and a rotary encoder. The miniature sensor does not require a special space for installation. Generally, inexpensive commercial steels with high strength are used for the torque drive shaft of an automobile, although their magnetic properties are quite poor. With this system, instantaneous torque can be accurately measured in real time, even of a shaft made of a commercial steel. Therefore, the application of this system to automobiles would be effective. The torque was measured within an error of 2% FS in spite of using a commercial shaft (carbon steel S43C).<>