Patents by Inventor Keith J. Reckdahl

Keith J. Reckdahl 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).

  • Onboard attitude control using reaction wheels
    Patent number: 6285928
    Abstract: An onboard attitude control system is constructed to utilize a four reaction wheel system having a reference axis, wherein at least three of the reaction wheel spin axes are oriented obliquely to the reference axis. Current attitude is estimated based on uploaded orbital data, onboard sensed earth and sun position data, and attitude data sensed by a three axes gyroscope system. Current attitude is compared to mission attitude to calculate an error which is transformed to a trihedral axes adjustment command to actuate the reaction wheel system.
    Type: Grant
    Filed: January 6, 2000
    Date of Patent: September 4, 2001
    Assignee: Space Systems/Loral, Inc.
    Inventors: Scott W. Tilley, Thomas J. Holmes, Keith J. Reckdahl
  • Wheel speed control system for spacecraft with rejection of null space wheel momentum
    Patent number: 6141606
    Abstract: A spacecraft attitude control system uses at least four reaction wheels In order to minimize reaction wheel speed and therefore power, a wheel speed control means system is provided. The wheel speed control means monitors the wheel speeds and controls wheel speed nullspace components to keep the wheel speeds as small as possible.
    Type: Grant
    Filed: July 28, 1998
    Date of Patent: October 31, 2000
    Assignee: Space Systems/Loral, Inc.
    Inventor: Keith J. Reckdahl