A new micromotor that is powered by the mechanical rectification of oscillatory motion is conceived, designed and fabricated. Its operational characteristic is quite rich and exhibits various modes of excitations. The idea explored in the design of this novel device is completely different than other micromotors reported in the literature. It consists of a rotor with elastic fins and linear actuators located on its perimeter and it operates as follows. When the actuators move toward the fins, the friction between the actuator edge and the tip of the fins causes them to deform. This deformation applies a force to the rotor that has both tangential and normal components. The tangential components results in a twisting action on the rotor, setting it into rotation. When actuators move away from the fins, the fins are released and allowed to move back to their original position. Continuous rotation is achieved by matching the oscillations of the actuators with the movement of the adjacent fins. The torque of this device is quite large (mN.m for 0.5 micrometers rotor radius) and can be adjusted by the radius of the actuator, the length and elastic properties of the fins, the tilt angle of the fins with respect to the rotor, the force exerted by the actuators, the vibration frequency and the number of fins, and by adjusting the friction between actuators and the fins. Experimental data using a prototype micrometer will be given and various application of the micromotor in optical MEMS and fluidics will be discussed.

Date Published: 15 March 1998
PDF: 9 pages
Proc. SPIE 3276, Miniaturized Systems with Micro-Optics and Micromechanics III, (15 March 1998); doi: 10.1117/12.302406

Published in SPIE Proceedings Vol. 3276:
Miniaturized Systems with Micro-Optics and Micromechanics III
M. Edward Motamedi; Rolf Goering, Editor(s)