Patents by Inventor Randolph H. Cabell

Randolph H. Cabell has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Compact active vibration control system for a flexible panel
    Patent number: 8760039
    Abstract: A diamond-shaped actuator for a flexible panel has an inter-digitated electrode (IDE) and a piezoelectric wafer portion positioned therebetween. The IDE and/or the wafer portion are diamond-shaped. Point sensors are positioned with respect to the actuator and measure vibration. The actuator generates and transmits a cancelling force to the panel in response to an output signal from a controller, which is calculated using a signal describing the vibration. A method for controlling vibration in a flexible panel includes connecting a diamond-shaped actuator to the flexible panel, and then connecting a point sensor to each actuator. Vibration is measured via the point sensor. The controller calculates a proportional output voltage signal from the measured vibration, and transmits the output signal to the actuator to substantially cancel the vibration in proximity to each actuator.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: June 24, 2014
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Noah H. Schiller, Randolph H. Cabell, Daniel F. Perey
  • Jet engine exhaust nozzle flow effector
    Patent number: 8683807
    Abstract: A jet engine exhaust nozzle flow effector is a chevron formed with a radius of curvature with surfaces of the flow effector being defined and opposing one another. At least one shape memory alloy (SMA) member is embedded in the chevron closer to one of the chevron's opposing surfaces and substantially spanning from at least a portion of the chevron's root to the chevron's tip.
    Type: Grant
    Filed: April 28, 2011
    Date of Patent: April 1, 2014
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Travis L. Turner, Roberto J. Cano, Richard J. Silox, Ralph D. Buehrle, Christopher M. Cagle, Randolph H. Cabell, George C. Hilton
  • Compact Active Vibration Control System for a Flexible Panel
    Publication number: 20130113338
    Abstract: A diamond-shaped actuator for a flexible panel has an inter-digitated electrode (IDE) and a piezoelectric wafer portion positioned therebetween. The IDE and/or the wafer portion are diamond-shaped. Point sensors are positioned with respect to the actuator and measure vibration. The actuator generates and transmits a cancelling force to the panel in response to an output signal from a controller, which is calculated using a signal describing the vibration. A method for controlling vibration in a flexible panel includes connecting a diamond-shaped actuator to the flexible panel, and then connecting a point sensor to each actuator. Vibration is measured via the point sensor. The controller calculates a proportional output voltage signal from the measured vibration, and transmits the output signal to the actuator to substantially cancel the vibration in proximity to each actuator.
    Type: Application
    Filed: November 8, 2011
    Publication date: May 9, 2013
    Applicant: U. S.A. as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Noah H. Schiller, Randolph H. Cabell, Daniel F. Perey
  • Jet Engine Exhaust Nozzle Flow Effector
    Publication number: 20110203288
    Abstract: A jet engine exhaust nozzle flow effector is a chevron formed with a radius of curvature with surfaces of the flow effector being defined and opposing one another. At least one shape memory alloy (SMA) member is embedded in the chevron closer to one of the chevron's opposing surfaces and substantially spanning from at least a portion of the chevron's root to the chevron's tip.
    Type: Application
    Filed: April 28, 2011
    Publication date: August 25, 2011
    Applicant: U. S. A. as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Travis L. Turner, Roberto J. Cano, Richard J. Silox, Ralph D. Buehrle, Christopher M. Cagle, Randolph H. Cabell, George C. Hilton
  • Jet engine exhaust nozzle flow effector
    Patent number: 7958733
    Abstract: A jet engine exhaust nozzle flow effector is a chevron formed with a radius of curvature with surfaces of the flow effector being defined and opposing one another. At least one shape memory alloy (SMA) member is embedded in the chevron closer to one of the chevron's opposing surfaces and substantially spanning from at least a portion of the chevron's root to the chevron's tip.
    Type: Grant
    Filed: June 14, 2007
    Date of Patent: June 14, 2011
    Assignee: The United States of America as represented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Travis L. Turner, Roberto J. Cano, Richard J. Silcox, Ralph D. Buehrle, Christopher M. Cagle, Randolph H. Cabell, George C. Hilton
  • Dual-use transducer for use with a boundary-stiffened panel and method of using the same
    Patent number: 7893602
    Abstract: A transducer for use with a boundary-stiffened panel has an inter-digitated electrode (IDE) and a piezoelectric wafer portion positioned therebetween. The IDE and/or the wafer portion are triangular, with one edge or side aligned with a boundary edge of the panel. The transducer generates and transmits an output force to the panel in response to an input voltage signal from a sensor, which can be another transducer as described above or an accelerometer. A controller can generate an output force signal in response to the input voltage signal to help cancel the input voltage signal. A method of using the transducer minimizes vibration in the panel by connecting multiple transducers around a perimeter thereof. Motion is measured at different portions of the panel, and a voltage signal determined from the motion is transmitted to the transducers to generate an output force at least partially cancelling or damping the motion.
    Type: Grant
    Filed: December 4, 2008
    Date of Patent: February 22, 2011
    Assignee: The United States of America as reprensented by the Administrator of the National Aeronautics and Space Administration
    Inventors: Noah H. Schiller, Randolph H. Cabell
  • Jet Engine Exhaust Nozzle Flow Effector
    Publication number: 20080272232
    Abstract: A jet engine exhaust nozzle flow effector is a chevron formed with a radius of curvature with surfaces of the flow effector being defined and opposing one another. At least one shape memory alloy (SMA) member is embedded in the chevron closer to one of the chevron's opposing surfaces and substantially spanning from at least a portion of the chevron's root to the chevron's tip.
    Type: Application
    Filed: June 14, 2007
    Publication date: November 6, 2008
    Applicant: Administrator of the National Aeronautics and and Space Administration
    Inventors: Christopher M. Cagle, Randolph H. Cabell, Travis L. Turner, Roberto J. Cano, Richard J. Silcox, Ralph D. Buehrle, George C. Hilton