Patents by Inventor Charles F. Barbs

Charles F. Barbs 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: 5010772
    Abstract: A capacitive measuring pad is constructed of transverse conductive strips separated by a compressible insulator to form a matrix of pressure sensitive capacitive nodes. The nodes are repetitively scanned in sequence by a microcomputer to measure their respective capacitances, from which measurements a pressure map is then derived. The resulting pressure map may be displayed on a color graphics monitor with different colors representing diffrent pressures. Node capacitance is found by measuring the response of the mode to a driving signal of a known voltage. This measurement is accomplished by connecting one of the node's transverse conductive strips to the driving source and the node's other conductive strips to a sense amplifier. In order to isolate the node of interest from the influence of surrounding nodes, all of the conductive strips except the two intersecting the selected node are connected to ground.
    Type: Grant
    Filed: May 5, 1989
    Date of Patent: April 30, 1991
    Assignee: Purdue Research Foundation
    Inventors: Joe D. Bourland, Charles F. Barbs, Leslie A. Geddes, Willis A. Tacker, Jr., George P. Graber