Abstract: A temperature correcting pressure gauge which has a diaphragm having at least one surface coupled to a source of pressure to be measured, the diaphragm first surface having a first FBG from a first optical fiber attached in an appropriately sensitive region of the diaphragm, a FBG from a second optical fiber attached to the opposite surface from the first FBG, the first and second FBGs reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second FBGs have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the FBGs also have closely matched pressure coefficients and temperature coefficients.

Abstract: A distributed temperature sensor system has a pulsed laser coupled to a circulator, the circulator having a laser input and coupling energy to an optical reference coil in series with a measurement fiber having loops or helical turns, the circulator having a backscatter signal port coupling backscattered reflections from the measurement fiber. The backscatter signal port is coupled to a switch and mux, the switch and mux selecting either an anti-Stokes filter or a Stokes filter, the output of the mux coupled to a photodetector, the photodetector coupled to a histogram processor synchronized to the pulsed laser enable. The histogram processor uses the anti-Stokes and Stokes histogram counts associated with a sensor region to estimate a temperature of that sensor region.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A temperature correcting pressure gauge which has a diaphragm having at least one surface coupled to a source of pressure to be measured, the diaphragm first surface having a first FBG from a first optical fiber attached in an appropriately sensitive region of the diaphragm, a FBG from a second optical fiber attached to the opposite surface from the first FBG, the first and second FBGs reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second FBGs have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the FBGs also have closely matched pressure coefficients and temperature coefficients.

Abstract: A temperature correcting pressure gauge which has a diaphragm having at least one surface coupled to a source of pressure to be measured, the diaphragm first surface having a first FBG from a first optical fiber attached in an appropriately sensitive region of the diaphragm, a FBG from a second optical fiber attached to the opposite surface from the first FBG, the first and second FBGs reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second FBGs have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the FBGs also have closely matched pressure coefficients and temperature coefficients.

Abstract: A biopsy needle has a cylindrical shell outer cannula and a stylet consisting of an inner stylet and outer stylet, both of which are inserted into the cylindrical cannula. The outer stylet has a series of strain relieved slits which provide bending over a deflection region in one direction, and the outer stylet is formed from a material such as a shape memory alloy (SMA) having a superelastic phase. The deflection is generated by an SMA wire spanning a deflection extent and attached to the outer stylet on either side of the deflection extent. The inner stylet, when positioned inside the outer stylet, has one or more actuation fibers which couple optical energy into the SMA wire or hollow SMA tube, causing a deflection of the outer stylet over the deflection extent, with the optical energy provided to the actuation fibers for control of the deflection. Additional fibers may be placed in the inner stylet to measure temperature and to measure deflection.

Abstract: A biopsy needle has a cylindrical shell outer cannula and a stylet consisting of an inner stylet and outer stylet, both of which are inserted into the cylindrical cannula. The outer stylet has a series of strain relieved slits which provide bending over a deflection region in one direction, and the outer stylet is formed from a material such as a shape memory alloy (SMA) having a superelastic phase. The deflection is generated by an SMA wire spanning a deflection extent and attached to the outer stylet on either side of the deflection extent. The inner stylet, when positioned inside the outer stylet, has one or more actuation fibers which couple optical energy into the SMA wire or hollow SMA tube, causing a deflection of the outer stylet over the deflection extent, with the optical energy provided to the actuation fibers for control of the deflection. Additional fibers may be placed in the inner stylet to measure temperature and to measure deflection.

Abstract: A drill has a stationary drive mechanism coupled to a rotating drill, the rotating drill having a serpentine optical fiber positioned on an inner shell having a serpentine groove with fiber Bragg gratings (FBGs) coupled to the inner shell and arranged parallel to the central axis of rotation for measurement of axial forces and also positioned circumferentially for measurement of drill torque. The FBGs are arranged on a single optical fiber and coupled to a broadband optical source such that reflected optical energy is directed to an interrogator for estimate of strain at each FBG. The FBG responses may also be examined dynamically to estimate material hardness during a drilling operation.

Abstract: A biopsy needle has a cylindrical shell outer cannula and a stylet consisting of an inner stylet and outer stylet, both of which are inserted into the cylindrical cannula. The outer stylet has a series of strain relieved slits which provide bending over a deflection region in one direction, and the outer stylet is formed from a material such as a shape memory alloy (SMA) having a superelastic phase. The deflection is generated by an SMA wire spanning a deflection extent and attached to the outer stylet on either side of the deflection extent. The inner stylet, when positioned inside the outer stylet, has one or more actuation fibers which couple optical energy into the SMA wire, causing a deflection of the outer stylet over the deflection extent, with the optical energy provided to the actuation fibers for control of the deflection.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A thermal protection system (TPS) test plug has optical fibers with FBGs embedded in the optical fiber arranged in a helix, an axial fiber, and a combination of the two. Optionally, one of the optical fibers is a sapphire FBG for measurement of the highest temperatures in the TPS plug. The test plug may include an ablating surface and a non-ablating surface, with an engagement surface with threads formed, the threads having a groove for placement of the optical fiber. The test plug may also include an optical connector positioned at the non-ablating surface for protection of the optical fiber during insertion and removal.

Abstract: A plurality of AWG filters with aliasing responses are selected such that the wavelength range of a fundamental response of the AWG filters results in the aliased range of AWG filters to be adjacent to a fundamental range of the AWG filters. A plurality of optical sources is provided sufficient to cover each fundamental wavelength range and each alias wavelength range of the AWG filters. When a single one of the optical sources is enabled, reflected optical energy from a series string of FBGs coupled to the optical source is applied to the plurality of AWG filters, and the AWG output in combination with the wavelength range of the optical source is used to discriminate reflected wavelength from the FBG sensors.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: A wavelength interrogator is coupled to a circulator which couples optical energy from a broadband source to an optical fiber having a plurality of sensors, each sensor reflecting optical energy at a unique wavelength and directing the reflected optical energy to an AWG. The AWG has a detector coupled to each output, and the reflected optical energy from each grating is coupled to the skirt edge response of the AWG such that the adjacent channel responses form a complementary pair response. The complementary pair response is used to convert an AWG skirt response to a wavelength.

Abstract: A movement and expression sensor has a plurality of fiber Bragg gratings (FBG) disposed along the length of an optical fiber, and the optical fiber is placed in contact with a subject's skin surface. The sensors are interrogated for reflected wavelength, which is converted into a temperature or a strain. A series of such measurements can be made to determine the movement or position of the sensor location. A garment may be formed using the sensors and an elastomeric material, such that the sensors may be worn and removed, and the movements of the elastomer in the areas of sensors measured as a wavelength shift to characterize movement or estimate location. The elastomeric garment may be formed as a mask, or a sock, such as for use with a face, or foot.

Abstract: A wavelength interrogator is coupled to a circulator which couples optical energy from a broadband source to an optical fiber having a plurality of sensors, each sensor reflecting optical energy at a unique wavelength and directing the reflected optical energy to an AWG. The AWG has a detector coupled to each output, and the reflected optical energy from each grating is coupled to the skirt edge response of the AWG such that the adjacent channel responses form a complementary pair response. The complementary pair response is used to convert an AWG skirt response to a wavelength.

Abstract: A biopsy needle has a central axis and includes one or more sensing regions, each sensing region formed by a plurality of sensing optical fibers located over a particular extent of said central axis and inside the outer shell of the needle. The sensing optical fibers are coupled to a wavelength interrogator. A steerable catheter has a central axis and outer shell, the outer shell coupled to a plurality of optical fibers in sensing regions and actuation regions, the sensing regions formed over particular extents of the central axis by bonding gratings to the inner surface of the outer shell, and the actuation regions formed by coupling optical energy into shape memory alloys bonded to the outer shell.

Abstract: An optical ring network for fixed length messages from a plurality of nodes for transmission to different nodes uses a plurality of wavelengths for transmission, and messages for transmission are ordered and arranged on a per-wavelength basis to minimize a transmit finish time. Each node may be operated in an ADM (add drop multiplexer) mode where an optical node removes information on a particular wavelength and adds information on the same particular wavelength, or each node may be operated in a CDC (colorless, directionless, contentionless) mode where information is assigned to a wavelength according to a selection algorithm which may place it on any wavelength without regard to an original node wavelength. The selection algorithm optimizes selection of messages and wavelengths for transmit finish time.

Abstract: A temperature correcting pressure gauge which has a substrate having at least one surface coupled to a source of pressure to be measured, the substrate first surface having a first fiber Bragg grating from a first optical fiber attached in an appropriately sensitive region of the substrate, a fiber Bragg grating from a second optical fiber attached to the opposite surface from the first fiber Bragg grating, the first and second fiber Bragg gratings reflecting or transmitting optical energy of decreasing or increasing wavelength, respectively, in response to an applied pressure. The first and second fiber Bragg gratings have nominal operating wavelength ranges that are adjacent to each other but are exclusive ranges and the fiber Bragg gratings also have closely matched pressure coefficients and temperature coefficients.