Abstract: A rotational energy harvesting apparatus includes a rotor of magnets and a ring of linear-based kinetic energy harvesters. The rotor of magnets is fixed to a rotational source and is caused to sweep past the linear-based kinetic energy harvesters. The rotating magnets compel kinetic energy to be induced in the linear-based kinetic energy harvesters. The kinetic energy is converted into electrical energy.

Abstract: A method includes passing a portion of an optical signal through an aperture of a sensor having a sensing element, wherein the portion of the optical signal that passes through the aperture is an inner portion of the optical signal and the portion of the optical signal that does not pass through the aperture is an outer portion of the optical signal; producing a sensed signal by sensing the outer portion of the optical signal with the sensing element; and controlling the source of the optical signal using the sensed signal. A system for implementing the method includes an optical energy source and a sensor having an optical sensing portion and an aperture therein. The system may also include an optical isolator, a detection element, and a controller for controlling the optical energy source. The system may be used within a MEMS-based system.