CAD OF A DIRECT-DRIVE ROTARY MOTOR BASED ON GIANT MAGNETOSTRICTIVE ALLOYS

Highly magnetostrictive materials such as TB3Dy7Fe2, commercially know n as Terfenol-D, have been used to date in a variety of devices such a s high power actuators and linear motors. The authors are investigatin g a finite element model devoted to Computer Aided Design (CAD) of a d irect micro-stepping rotary motor. Such a motor would be a high torque micro-radian stepper, capable of precision movements and self-braking in the power off state. The thrust of this paper is to test the valid ity of the so-called ''weak coupling'' approach on a motor based on th e proven inch worm technique. Comparison between numerical outputs fro m the model and test results on prototype hardware will be presented.