Patents by Inventor Douglas P. Pelletier

Douglas P. Pelletier 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: 5583757
    Abstract: A method of input signal resolution in a process control system where each of the actively redundant process control computers performs a common arbitration process on corresponding input signals. Blocks of corresponding input signals are mutually exchanged by the actively redundant process control computers, and an initial check is made to determine if these input signals are valid. For input signals representing valid analog values, a determination is made as to whether a predefined tolerance has been exceeded between corresponding input signals in the present process control cycle. When the predefined tolerance has been exceeded, then a check will be made to determine the predefined tolerance was also exceeded in the last process control cycle. If the predefined tolerance was not exceeded in the last process control cycle, then the analog input value selected during the last process control cycle will be employed in the present process control cycle.
    Type: Grant
    Filed: August 4, 1992
    Date of Patent: December 10, 1996
    Assignee: The Dow Chemical Company
    Inventors: Eloy Baca, Jr., Wayne P. Dupree, Donald J. Grinwis, Johannes C. Kanse, Douglas P. Pelletier, Oscar E. Schulze