Abstract: A magnetic indexer for locating a device producing a magnetic field in a blind or inaccessible position of a work piece. A magnet is initially placed on a first side of the work piece such that a magnetic field produced by the magnet extends through the work piece and substantially perpendicular to a surface of the work piece. A device comprising a plurality of probes for sensing magnetic fields is then positioned over a second surface of the work piece. The probes are then moved over the second surface to determine the location of the axis of the magnet via the strength of the sensed magnetic field. Once the position of the axis of the magnet is determined, the work surface is either marked or worked on through the platform on which the probes are positioned. In particular, a hole may be accurately drilled or otherwise formed directly over the magnet even when the first surface of the work piece cannot be seen.

Abstract: A method for locating a device, which produces a field, with a probe assembly affected by the field. The method may involve: placing a device on a first side of a work piece; producing a field with the device through the work piece; using a robot to hold and to place a probe assembly adjacent a second side of the work piece; providing information from the probe assembly to the robot that is used by the robot to move the probe assembly to substantially determine a position of the device; determining a location of a center field axis of the field with the probe assembly; and providing a physical confirmation of the center field axis to a user.

Abstract: A hand held non-destructive testing device has a frame which supports an NDI sensor and incorporates means for translation across a surface to be inspected with position registration and resilient means for maintaining the sensor and the translation means in intimate contact with the surface. An ergonomic handle is mounted to the frame for manually controlled translation of the frame incorporates a plurality of control means for control of the sensor in scanning of the surface under inspection.

Abstract: A magnetic indexer for locating a device producing a magnetic field in a blind or inaccessible position of a work piece. A magnet is initially placed on a first side of the work piece such that a magnetic field produced by the magnet extends through the work piece and substantially perpendicular to a surface of the work piece. A device comprising a plurality of probes for sensing magnetic fields is then positioned over a second surface of the work piece. The probes are then moved over the second surface to determine the location of the axis of the magnet via the strength of the sensed magnetic field. Once the position of the axis of the magnet is determined, the work surface is either marked or worked on through the platform on which the probes are positioned. In particular, a hole may be accurately drilled or otherwise formed directly over the magnet even when the first surface of the work piece cannot be seen.

Abstract: A method for locating a device, which produces a field, with a probe assembly affected by the field. The method may involve: placing a device on a first side of a work piece; producing a field with the device through the work piece; using a robot to hold and to place a probe assembly adjacent a second side of the work piece; providing information from the probe assembly to the robot that is used by the robot to move the probe assembly to substantially determine a position of the device; determining a location of a center field axis of the field with the probe assembly; and providing a physical confirmation of the center field axis to a user.

Abstract: A magnetic indexer for locating a device producing a magnetic field in a blind or inaccessible position of a work piece. A magnet is initially placed on a first side of the work piece such that a magnetic field produced by the magnet extends through the work piece and substantially perpendicular to a surface of the work piece. A device comprising a plurality of probes for sensing magnetic fields is then positioned over a second surface of the work piece. The probes are then moved over the second surface to determine the location of the axis of the magnet via the strength of the sensed magnetic field. Once the position of the axis of the magnet is determined, the work surface is either marked or worked on through the platform on which the probes are positioned. In particular, a hole may be accurately drilled or otherwise formed directly over the magnet even when the first surface of the work piece cannot be seen.

Abstract: A non-destructive testing device has an excitation coil with a plurality of conductor ribbons attached to a flexible membrane. A frame supports the membrane and incorporates wheels for translation across a surface to be inspected and resilient suspension for maintaining the membrane with the excitation coil and wheels in intimate contact with the surface, the membrane flexing to maintain contact with a smoothly curved surface as found in aircraft structures. A magnetoresitive (MR) array is supported within the frame inserted in the membrane to be in close proximity to the surface. The MR array detects the magnetic field resulting from the eddy currents created by the excitation coil for identification of cracks or features beneath the surface under inspection.

Abstract: A method for locating a device producing a magnetic field in a blind or inaccessible position of a work piece. A magnet is initially placed on a first side of the work piece such that a magnetic field produced by the magnet extends through the work piece. Probes are then positioned over a second surface of the work piece to determine the location of the axis of the magnet via the strength of the sensed magnetic field and the location where the strength measurements are made. Once the position of the axis of the magnet is determined, the work surface is either marked or worked on through the platform on which the probes are positioned. In particular, the present invention allows a very accurate positioning of a work tool on the second surface without the need to first visualize the first surface of the work piece.

Abstract: A magnetic indexer for locating a device producing a magnetic field in a blind or inaccessible position of a work piece. A magnet is initially placed on a first side of the work piece such that a magnetic field produced by the magnet extends through the work piece and substantially perpendicular to a surface of the work piece. A device comprising a plurality of probes for sensing magnetic fields is then positioned over a second surface of the work piece. The probes are then moved over the second surface to determine the location of the axis of the magnet via the strength of the sensed magnetic field. Once the position of the axis of the magnet is determined, the work surface is either marked or worked on through the platform on which the probes are positioned. In particular, a hole may be accurately drilled or otherwise formed directly over the magnet even when the first surface of the work piece cannot be seen.

Abstract: A method for locating a device producing a magnetic field in a blind or inaccessible position of a work piece. A magnet is initially placed on a first side of the work piece such that a magnetic field produced by the magnet extends through the work piece. Probes are then positioned over a second surface of the work piece to determine the location of the axis of the magnet via the strength of the sensed magnetic field and the location where the strength measurements are made. Once the position of the axis of the magnet is determined, the work surface is either marked or worked on through the platform on which the probes are positioned. In particular, the present invention allows a very accurate positioning of a work tool on the second surface without the need to first visualize the first surface of the work piece.

Abstract: A fiber optic magnetic field gradiometer uses the first derivative of a magnetic field associated with a corrosion process to determine the location on the surface of a metal of the corrosion at its onset or very early stages, whereas eddy current type detectors detect the corrosion only after a significant amount of the metal has already been removed. Two adjacent flat magnetic transducers made of magneto-strictive glass, onto which are secured two optical fibers, are immersed in an applied magnetic field to null out material differences in the earth's magnetic field. The optical fibers are secured to a surface of each transducer to provide a relatively flat sandwiched pair of transducers. The flat magnetic transducers are sandwiched together and scanned over the metal surface. A magnetic field associated with the corrosion process in the direction of the axis of the flat magnetic transducers causes an optical path length change in the fibers.

Abstract: An electron beam is directed into a first region containing gaseous molecules which capture electrons from the beam and then dissociate to produce negative ions. The ions are accelerated to the desired energy electrostatically and drawn to a second region where they are exposed to an intra-cavity laser beam which traverses their path. The laser is chosen to have a wevelength which will cause photodetachment of electrons to form neutral atoms. Simultaneously with the above, the electron beam and ions are collimated with a magnetic field. The neutral atoms are separated from any remaining ions or electrons by a repelling electrical potential provided by a repeller plate or the like.

Abstract: An electron beam is directed into a first region containing gaseous molecules which capture electrons from the beam and then dissociate to produce negative ions. The ions are accelerated to the desired energy electrostatically and drawn to a second region where they are exposed to an intra-cavity laser beam which traverses their path. The laser is chosen to have a wavelength which will cause photodetachment of electrons to form neutral atoms. Simultaneously with the above, the electron beam and ions are collimated with a magnetic field. The neutral atoms are separated from any remaining ions or electrons by a repelling electrical potential provided by a repeller plate or the like.

Abstract: An optical repeater that amplifies and reshapes an input pulse without converting the pulse into the electrical domain. The repeater comprises an optical gain device, a mode selector, and an optical thresholding material. The optical gain device comprises an optical gain material with anti-reflection coatings at its input and output ports. The mode selector receives an optical signal amplified by the gain medium, and preferentially transmits one or more preselected spatial modes to the thresholding material, which shapes the pulses for retransmission.

Abstract: A fiber-optic magnetic field gradiometer uses a plurality of magnetic transducers to simultaneously determine multicomponents of the gradient and field strength of an external magnetic field so as to permit accurate determination of the location of a ferromagnetic object located in an array of objects. The magnetic transducers are made of several layers of magnetostrictive glass which are wrapped with an optical fiber and immersed in an applied magnetic field to null out material differences and the earth's magnetic field. The null conditions for each adjacent pair are accomplished without disturbing the null conditions of the other adjacent pair. The nulling technique may be accomplished in real time and does not require cutting off the drive signals to adjacent coils. Thus the nulling may be accomplished simultaneously for all coils as the balancing of each coil is independent of its neighbors.

Abstract: A fiber-optic magnetic field gradiometer uses the second derivative of a magnetic field to determine the location of a ferromagnetic object located in an array of objects. Three adjacent magnetic transducers made of several layers of magnetostrictive glass are wrapped with an optical fiber and immersed in an applied magnetic field to null out material differences and the earth's magnetic field. The null conditions for each adjacent pair are accomplished without disturbing the null conditions of the other adjacent pair. A magnetic field to be detected along the axes of the magnetic transducers causes an optical path length change in the fibers. The overall path length change is proportional to the second derivative of the magnetic field.

Abstract: A specimen of molecules containing the desired element is contained in a low-pressure environment and is exposed to a beam of electrons of predetermined energy, causing the electrons to be captured by the molecules. The reaction is chosen so that there is a natural dissociation into an ion containing the desired element. The reaction region is subjected to an electrical field that accelerates the ions and removes them from the reaction region, at which time the ions are exposed to a laser beam of a wavelength sufficient to photodetach a substantial number of electrons from the ions, producing neutral atoms of the desired element. The entire particle stream exiting the interaction region is subjected to a magnetic field that bends the charged ions away from the neutral atoms so that the neutral atoms can then be directed to a test specimen or collection device, as the case may be.

Abstract: An optical displacement sensor serves to sense variations in the displacement of a test article. This is achieved by securing a portion of the length of an optical fiber between two spaced points on a test article and then supplying a laser beam to propagate through the measurement fiber as well as through a reference fiber of the same length. Expansions and contractions of the test article causes changes in length of the measurement fiber. The light beams are recoupled to produce an interference pattern which varies as a function of variations in displacement of the test article.