Patents by Inventor Susan M. Hubert

Susan M. Hubert 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).

  • Patent number: 5263666
    Abstract: A spacecraft includes bipropellant and monopropellant engines or thrusters. The oxidizer-fuel mixture ratio of the bipropellant engine is not known exactly. The spacecraft is loaded with only sufficient oxidizer to achieve the velocity for transfer from an intermediate orbit to geosynchronous orbit if the mixture ratio is nominal. Therefore, more fuel can be loaded. If the bipropellant engine burn is nominal, there is no excess oxidizer when on-orbit and more fuel is available for stationkeeping. If the burn is oxidizer-rich, there is a velocity shortfall, which is made up by firing monopropellant engines. If the burn is oxidizer-lean, the geosynchronous orbit is achieved with a load of excess oxidizer, which must be moved during each stationkeeping maneuver. A net gain of stationkeeping time results in any of the three mixture ratio cases by comparison with loading of sufficient oxidizer for a full bipropellant burn under worst-case mixture conditions.
    Type: Grant
    Filed: December 16, 1988
    Date of Patent: November 23, 1993
    Assignee: General Electric Co.
    Inventors: Susan M. Hubert, Keith Davies