Satcon Technology Corporation

Ralph C Fenn

Richard L Hockney

Bruce G Johnson

David B Eisenhaure

Shankar Jagannathan

Michael Jonathan Gerver

Monique Gaffney

Kevin J Leary

A narrow band controller for suppressing disturbances from a source responsive to an input signal representative of the frequency spectrum of a disturbance from the source and providing an output signal having a similar frequency spectrum as the frequency spectrum of the input signal based on the input signal including delay logic for delaying, for a period of time, the received input signal for assuring the output signal has a phase different than the phase of said input signal.

Narrow band controller

A very light, high force reaction-mass actuator using high energy density magnetostrictive material to accelerate a mass, producing a reaction force that can be used to oppose vibration forces. The reaction-mass actuator is configured having an axially symmetric design that features a Terfenol-D rod as a core. Surrounding the rod is a magnetic coil which provides the changing magnetizing field used to actively control magnetostrictive strain of the Terfenol rod. The magnetic coil also provides a magnetic flux based on a D.C. current, for biasing the Terfenol rod. The magnetic coil, disposed about the fixed magnetostrictive rod, is incorporated into a reaction mass assembly that is suspended and sealed inside an enclosed, stiff outer shell or housing by an elastomeric material mounting configuration that facilitates an output force with suppressed harmonic content. In addition, the elastomeric mounting configuration provides sealing protection against external factors. In one embodiment, the magnetic coil is wound on a bobbin effecting a movable mass that is accelerated to produce a force on a mounting surface. The Terfenol rod is placed under axially compressive stress by a simple mechanical preloading mechanism. This increases strain in the Terfenol rod while providing a return spring for the reaction mass when it has reached its maximum stroke.

Light reaction mass actuator

A magnetoelastic magnetometer having a magnetoelastic member for placement in a magnetic field, An effect on the stiffness of the magnetoelastic member caused by the magnetic field is measured, and magnitude of the field is determined in response.

Magnetoelastic magnetometer

A system and method for damping narrow band axial vibrations of a rotating device in which a reaction mass is coupled to the rotating device and a reaction mass actuator is employed to move the reaction mass axially along the rotating device. An effect of vibrations on the rotating device is then measured, and in response the reaction mass is moved axially to damp the effect of vibrations and so the vibrations.

Growing community of inventors

Cambridge, MA, United States of America

Ralph C Fenn