Patents Assigned to Photo Acoustic Technology, Inc.
  • Patent number: 4821206
    Abstract: A robot positioning apparatus for use with robot devices having a movable portion, wherein the movable portion may be spatially oriented to, and controllably spaced from, a reference surface. Initial locating of the reference surface is accomplished by an approximate positioning subsystem using multiple, angularly oriented units which send and receive acoustic orientation positioning signals in search of the reference surface. Once a return signal is received, switching logic indentifies the necessary reorienting of the movable portion to achieve approximately the proper facing relationship of the movable portion to the surface. For precise positioning and ranging after the facing relation is established, a precision positioning subsystem emits an acoustic signal toward the surface, and a response signal is received back from the surface by at least two, and preferably three, receivers mounted upon the movable portion of the robot device.
    Type: Grant
    Filed: October 23, 1987
    Date of Patent: April 11, 1989
    Assignee: Photo Acoustic Technology, Inc.
    Inventor: Arvind Arora
  • Patent number: 4718023
    Abstract: A robot positioning apparatus for use with robot devices having a movable portion, wherein the movable portion may be spatially oriented to, and controllably spaced from, a reference surface. Initial locating of the reference surface is accomplished by an approximate positioning subsystem using multiple, angularly oriented units which send and receive acoustic orientation positioning signals in search of the reference surface. Once a return signal is received, switching logic identifies the necessary reorienting of the movable portion to achieve approximately the proper facing relationship of the movable portion to the surface. For precise positioning and ranging after the facing relation is established, a precision positioning subsystem emits an acoustic signal toward the surface, and a response signal is received back from the surface by at least two, and preferably three, receivers mounted upon the movable portion of the robot device.
    Type: Grant
    Filed: November 27, 1984
    Date of Patent: January 5, 1988
    Assignee: Photo Acoustic Technology, Inc.
    Inventor: Arvind Arora
  • Patent number: 4590376
    Abstract: An instrument for monitoring the surface characteristics of materials, whereby the surface is characterized by measurement of a current of photo-emitted electrons flowing from the surface to a collector on the instrument. The instrument directs ultra violet light against the surface being measured, and the photoelectrons emitted are characteristic of surface features such as oxide thickness, contamination, or fatigue. The current of electrons emitted from the surface is compared with previously established limits for surface quality to provide an acceptability test of the surface. The instrument is portable and does not require the use of a vacuum chamber.
    Type: Grant
    Filed: May 30, 1984
    Date of Patent: May 20, 1986
    Assignee: Photo Acoustic Technology, Inc.
    Inventor: Tennyson Smith