Thomas A Millott

6856920, Feb 15, 2005

Feb 25, 2004

10/786686

Thomas A. Millott - Milford CT, US
Douglas G. MacMartin - San Gabriel CA, US
Christopher G. Park - Willington CT, US

Sikorsky Aircraft Corporation - Stratford CT

G06F019/00

702 56, 702 69, 700280

A noise or vibration control system improves the quality of adaptation estimates by filtering the input signals to the adaptation, selectively implementing a “dead-zone” during which adaptation does not occur and by selectively adding a dither signal to the control commands. The dead-zone is based on the magnitude of the changes in the control commands, which are responding to the changes in the sensor signals. The dead-zone can be applied to all actuators simultaneously, or can be applied to the adaptation of each actuator channel independently. To maintain identifiability, a “dither signal” is added to the control commands to “ping” the system to increase the amount of information available to the adaptive algorithm. The dither signal is preferably implemented on only one actuator channel at a time. Also, the dither amplitude for each channel is preferably set to be proportional to the current control amplitude.

7197147, Mar 27, 2007

Feb 27, 2002

10/083774

Thomas A. Millott - Milford CT, US
Douglas G. MacMartin - San Gabriel CA, US
Robert K. Goodman - West Hartford CT, US
James W. Fuller - Amston CT, US

Sikorsky Aircraft Corporation - Stratford CT

G10K 11/16

381 718, 381 7112, 244 1 N

A system and method reduces undesired noise or vibration in a vehicle. The ambient vibration is measured and command signals are generated over time. The command signals are generated based upon the measured vibration and based upon a control weighting. By varying the control weighting over time, the maximum possible performance is always obtained subject to the saturation constraints.

20020120415, Aug 29, 2002

Feb 27, 2002

10/083949

Thomas Millott - Milford CT, US
Douglas MacMartin - San Gabriel CA, US
Christopher Park - Willington CT, US

G06F019/00

702/069000

A noise or vibration control system improves the quality of adaptation estimates by filtering the input signals to the adaptation, selectively implementing a “dead-zone” during which adaptation does not occur and by selectively adding a dither signal to the control commands. The dead-zone is based on the magnitude of the changes in the control commands, which are responding to the changes in the sensor signals. The dead-zone can be applied to all actuators simultaneously, or can be applied to the adaptation of each actuator channel independently. To maintain identifiability, a “dither signal” is added to the control commands to “ping” the system to increase the amount of information available to the adaptive algorithm. The dither signal is preferably implemented on only one actuator channel at a time. Also, the dither amplitude for each channel is preferably set to be proportional to the current control amplitude. The quality of the adaptation estimates is also improved by filtering the input signals to the adaptation circuit, y=z, and v=u. Among other things, the filter matches the filtering applied by the harmonic estimator.

20140079234, Mar 20, 2014

Sep 14, 2012

13/618761

Donald J. Butts - Milford CT, US
William A. Welsh - North Haven CT, US
Thomas A. Millott - Milford CT, US
Stuart K. Drost - Shelton CT, US

SIKORSKY AIRCRAFT CORPORATION - Stratford CT

G10K 11/16

381 716, 381 711

A noise-suppression assembly of a mechanical drive system having a rotational frequency includes an audio filter unit configured to receive a first audio signal and a timing signal of the mechanical drive system. The audio filter unit generates a noise-cancellation signal based on a frequency of the timing signal to suppress a noise generated by the mechanical drive system and to apply the noise-cancellation signal to the first audio signal to produce a filtered first audio signal. The frequency of the timing signal is based on the rotational frequency of the mechanical drive system.

20150097074, Apr 9, 2015

Oct 3, 2013

14/045140

- Stratford CT, US
Thomas A. Millott - Milford CT, US

Sikorsky Aircraft Corporation - Stratford CT

B64C 27/00

244 1713

A system for active vibration control includes an actuator configured to reduce the impact of a vibratory load imposed on an airframe of a rotorcraft to an amount that is less than a threshold; and a controller configured to determine the vibratory load based on the data, and set an eccentric rotational speed of an actuator at a first frequency and modulate the eccentric rotational speed by a second frequency based on the vibratory load. Also a method includes obtaining, by the controller, data; determining, by the controller, a vibratory load based on the data; and setting, by the controller, an eccentric rotational speed of an actuator at a first frequency and modulating the eccentric rotational speed by a second frequency based on the vibratory load.