摘要:
A tool for forming a sensor coil that may be employed, for example, in a fiber optic gyroscope with reduced Shupe effect-induced bias. The tool includes a takeup reel having a cylindrical mandrel with inner flanges fixed to its opposed ends sandwiched between two outer flanges. Each of the inner flanges includes a pair of radially-directed apertures that form a radially-directed wedge therebetween. A recess in the planar portion of each of the outer flanges that contacts an inner flange is aligned with the apertures. This permits the winding of the sensor coil to form climbing turns at the ends of wound layers that lie outside an encapsulated fiber pack. Such turns, which join layers with overlying layers, avoid crossovers and the resultant stress that contributes significantly to Shupe effect-induced bias. A sensor coil having reduced internal stress is thus also provided.
摘要:
An improved dressing for the fiber optic leads of a fiber optic gyroscope sensing coil and method for forming the same. A pair of fiber optic leads connect the sensing coil of a rotation sensing device to an integrated optics chip. The fiber optic leads are originally arranged to extend around the fiber optic sensing coil in different directions. The leads are formed of unequal lengths, where the longer of the leads is extended along an outer circumference of the sensing coil. The longer lead is bent so that the circumferential direction of longer lead reverses itself, and the longer lead then extends around the sensing coil in the same direction as the shorter lead. A low modulus adhesive is applied to the leads and cured to initially bond the leads in place against the sensing coil. The pair of leads are then wound in the same circumferential direction adjacent to each other fashion around the outer circumference of the sensing coil. After the desired amount of winding has been completed, a predetermined length of each of the leads is left available to be routed to the rotation sensing device. The entire outer surface of the wound fiber optic leads surrounding the temporary adhesion is then coated with a low modulus adhesive and cured to bond the wound leads against the sensing coil structure.
摘要:
A potted sensor coil for a fiber optic gyroscope includes an inter-layer stress relief layer of lubricating material. The coil is wound into a known pattern. Various coil configurations can be realized in which a coating layer of lubricant relieves stressing at the interface between the outer jacket of the fiber and the coil potting material.
摘要:
The invention relates generally to a modular display panel for enclosing Commercial-Off-The-Shelf (“COTS”) display technologies. More particularly, the invention relates to a modular display panel for housing COTS light emitting or transmitting display subassemblies such as Liquid Crystal Displays (LCD) for military and other severe environments. The modular display assembly can comprise a base plate, a first frame, a window, a second, a circuit located, and a plurality of light emitting diodes mounted on the circuit board. The COTS light emitting or transmitting display subassembly can be connected to the second frame.
摘要:
The invention temperature controlled package comprises a case having sidewalls that form a closed perimeter; a cover; and a base having an input surface and an output surface. The sidewalls are integrally coupled to the base input surface to define an interior region. A heatsink has a top surface and a bottom surface. The heatsink bottom surface is attached to the input surface of a thermoelectric cooler. The bottom surface of the thermoelectric cooler is coupled to the base input surface of the case. The thermoelectric cooler responds to a control signal to move heat from the thermoelectric cooler input surface to the thermoelectric cooler output surface. In a first alternative embodiment, a laser diode coupled to the heat sink responds to an electrical input signal to providing an optical laser output signal. The optical output of the laser diode is coupled via a optical fiber through a fiberoptic feedthrough in a sidewall. The interior region is filled with xenon gas. A cover is welded on the sidewalls to form a sealed interior region with xenon gas therein. The xenon gas limits the movement of heat from the interior surface of the sidewalls and the interior surface of the cover to the surfaces of the thermoelectric cooler.
摘要:
The invention relates generally to a modular display panel for enclosing Commercial-Off-The-Shelf (“COTS”) display technologies. More particularly, the invention relates to a modular display panel for housing COTS light emitting or transmitting display subassemblies such as Liquid Crystal Displays (LCD) for military and other severe environments. The modular display assembly can comprise a base plate, a first frame, a window, a second, a circuit located, and a plurality of light emitting diodes mounted on the circuit board. The COTS light emitting or transmitting display subassembly can be connected to the second frame.
摘要:
A cover assembly includes a base, a cover and a hinge coupling the cover to the hinge. The hinge includes a body coupled to a rear face of the base and extends outwardly from a side edge of the base. The hinge has a leg oriented to contact an edge of the cover when the cover is pivoted to the open position. The edge frictionally engages the leg of the hinge to hold the cover in an open position and limit rotation of the cover.
摘要:
An apparatus in one example comprises a buffer layer located on a face that serves as a primary support for an optical fiber winding along a first general direction. The face is coupled with a body that serves as a primary support for the optical fiber winding along a second general direction. The optical fiber winding comprises an optical fiber wound about the body. The buffer layer serves to promote a decrease of one or more strain gradients among a plurality of portions of the optical fiber winding.
摘要:
A system and method for providing a rotation sensor for use in a fiber optic gyroscope including a centrally-located cylindrical hub having an improved slip interface positioned there around. The central hub has a substantially planar mounting flange extending from one of its ends, where the axis of rotation of the central hub is orthogonal to the plane of the mounting flange. A sensor coil comprising a plurality of layers of coaxial turns of optical fiber embedded in a potting material is formed around an outer surface of the interface. The interface allows the potted coil to expand or contract along the axial direction of the central hub due to thermal expansion while maintaining a constant thermal and mechanical connection between the interface and the potted coil. In this manner, the present invention maintains the integrity of the potted coil and its connection to the interface during thermal expansion of the potted coil, thus minimizing temperature-induced Shupe bias errors in the rotation sensor.
摘要:
Interconnection mechanisms for a laser gyroscope assembly (10) enable it to be rapidly and non-harmfully assembled and disassembled prior to a more durable interconnection, to facilitate repair and rework. The assembly includes a fiber optic spool (12), an inner shield (16) and an outer shield (18), which are formed of a stress-annealed magnetic and generally malleable material. The outer shield comprises upper and lower portions or parts (30, 32) whose first and second end segments (62, 66) respectively terminate the portions. Segment (66) has angled intersecting conical surfaces (74, 76) which engage surfaces (65, 67) on segment (62). Stops (80, 83) are formed respectively on the ends of the segments so that a distal end (68) contacts an interior ledge surface (80) of outer shield (34), thereby to limit the mutual engagement and to center the segment configuration interfit. The position and location of the stop allows the intersecting edges of surface (65, 67) of outer shield (34) to precisely contact reverse taper segment (76) of surface (70) at a point beneath intersection (78) to ensure positive retention and mechanical locking of the upper and lower portions of outer shield (18). A plurality of notches (84) are positioned evenly about the periphery of the lower portion of the outer shield at its intersection of the upper portion. Tangs (90, 92) of a tool (88) are inserted in seriatim within the spaces for gradual disassembly of the upper and lower outer shield portions without harm thereto. Inner shield (16) includes a cover (28) having two pairs of projections (130, 132) which can snap together, and a top annular segment (126) which is engageable with a centering projection (138) on end (26) of the spool. When the cover is secured to the spool, the top annular segment is flexed, but not deformed, to provide a spring bias and positive retention and, consequently, a solid and chatter-resistant engagement in a robust mechanical connection even under severe dynamic environments.