Micro-magnetic Rotational Wings in an Alternating Magnetic Field

Magnetic rotational wings that rotate in an alternating magnetic field were fabricated and analyzed. The rotational wings are composed of the rectangular-shaped magnetic wings and a thin rod in the center that acts as the axis of rotation. When the alternating magnetic field and the initial rotation are applied, the rotational wings keep on rotating at the same frequency as the magnetic field. The magnetization of the wings, the magnetic torque exerted on the wings and the resistance of the air are calculated and the rotation of the wings is simulated. When the thrust generated by the wings overcomes the weight of their own, the wings take off along the guide. The 165-mg 0,9-mm-long micro-rotational wings fabricated by micromachine technology succeeded in taking off at 570 Hz. The non-dimensional number Crw was introduced to represent the characteristics of the rotational wings. Crw increases, as the wing length decreases. Crw of around 1 mm long rotational wings was estimated to be 2.