Patents by Inventor Helena M. De Ruiter

Helena M. De Ruiter 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: 5492440
    Abstract: The accuracy of an apparatus for the movement of an object is increased by means of compensating for geometric errors and load and temperature induced deformations. The effects of the errors and deformations are stored in regularly updated compensation tables or parameterisations from which the error values as a function of position are available. The appropriate error values are selected while the complete momentary state of the apparatus can be taken into account. The derived error values can be used to correct the measured position in a feedback loop or to modify the steering signals for driving means without use of a feedback loop.
    Type: Grant
    Filed: April 25, 1994
    Date of Patent: February 20, 1996
    Assignee: U.S. Philips Corporation
    Inventors: Henricus A. M. Spaan, Johannes A. Soons, Helena M. De Ruiter