A rigid ring electrostatic harmonic wobble motor with axial field

The working principle of a novel wobble electrostatic micromotor and the fabrication of a prototype are presented. Surface micromachining of LPCVD (low-pressure chemical vapor deposited) polysilicon layers and sacrificial dioxide layer technology are used. For the prototype, a very high harmonic reduction of 1:20000 can be obtained through the vertical wobbling motion of a 200- mu m-diameter ring. Due to the planar technology aspect ratio, the electrostatic top drive of the wobbling ring used allows a much higher motor torque as in the case of direct drives or even harmonic side drives. Flexible elements permit the connection from the wobbling ring to a purely rotating hub.<>