Abstract: The invention is a method for compensating for coning in a strapdown inertial navigation system which utilizes groups of five successive incremental angles of rotation of a body-fixed coordinate system as measured by orthogonally-mounted gyros at regular measurement intervals, each group of five measurements being obtained during a group interval equal to five measurement intervals. The coning-compensated angular displacement of the body-fixed coordinate system about a fixed axis in space during a p'th group interval is obtained by summing the five measured incremental angles and a coning compensation term.

Abstract: The invention is a method for obtaining linear measures of one or more parameters p.sub.m of a device having one or more input ports i and an output port where m takes on integer values from 1 to M, M being an integer equal to or greater than 1, and i takes on integer values from 1 to I, I being an integer equal to or greater than 1. The device causes one or more input signals G.sub.i (p.sub.m)E.sub.ei (t) fed into one or more input ports to be transformed into an output signal comprising a summation over i of G.sub.i (p.sub.m)H.sub.i (p.sub.m)E.sub.oi (t) at the output port. The function G.sub.i (p.sub.m) is a weighting function associated with the i'th input port, E.sub.ei (t) is an excitation signal associated with the i'th input port, and E.sub.oi (t) is the transformation of the excitation signal E.sub.ei (t) that results from E.sub.ei (t) traversing the path from the input port i to the output port. The signals E.sub.ei (t) and E.sub.oi (t) are both independent of the parameter p.sub.m.

Abstract: A holder for an electrical or electronic component includes a body formed of electrically non-conductive material. The body is generally U-shaped having a pair of laterally spaced arms bridged by a bight. Conductive tracing on the arms establishes an electrical connection between the component and a printed circuit board when the holder is electrically connected to the printed circuit board and the terminals of a component contact the arms.

Abstract: This invention provides a low friction linear clearance seal for use in closed cycle cryogenic coolers. The clearance seal comprises a cylinder, a piston mounted within the cylinder for reciprocating movement and a self lubricating polymer liner bonded to the piston which forms an effective seal around the piston. The clearance seal improves the sealing capability between the piston and the cylinder and reduces heat generated by the motion of the piston along the cylinder wall. The clearance seal also improves the performance and reliability of the cryogenic cooler.

Abstract: A gyroscope component (10) and its variations (10a, 10b and 10c) includes a spool (12, 12a) which supports a ring-shaped fiber optic gyroscope coil (14). The spool has a base (26, 26a) which is provided with a central hole (38, 38a). A perpendicularly extending tubular wall (28, 28a) extends from the base or a cover (16, 16a), and may directly contact the coil or be separated therefrom by a non-adhesive material (29) or a space (30). The cover covers the spools and, with the spool and the tubular wall, forms a ring-shaped enclosure. Each coil has a generally trapezoidal shape and comprises an optical fiber winding wound about an axis and having a cross-sectional configuration that approximates a 45.degree. right triangle whose hypotenuse is formed by the sloped sides to provide a side which is sloped with respect to its axis. Three components (10, 10", 10"') are positioned respectively about three orthogonally disposed axes to form an assembly (50) and are supported within and enclosed by a housing (52).

Abstract: A rotation sensor for use in a fiber optic gyroscope includes a substantially-planar disk-like coil mounting member of titanium. A would sensor coil is supported by the member in an edgewise fashion, allowing free expansion of the sensor coil in the direction orthogonal to the plane of the member to minimize thermally-induced stressing of the sensor coil. In an alternative embodiment, the free-standing coil is effectively "split"; that is, one-half is mounted to one side of the member and the remainder to the other side in such a way that the sensitive axes are coincident. Edge ramps are provided in the member for guiding the continuous optical fiber comprising the coil segments from one side of the disk-like mounting member to the other without microbends.

Abstract: The invention is a method and apparatus for determining the phase difference of light waves after propagating through each of one or more two-path pairs, a two-path pair being two optical transmission paths connecting a common entry point to a common exit point. Coherent light pulses of predetermined duration are fed into the entry point of each two-path pair in a group of two-path pairs at predetermined time intervals, the pulse duration being subdivided into a plurality of predetermined time segments. The light has a different frequency during each time segment. The light pulses at the exit points of the two-path pairs are delayed by predetermined time increments and then combined into a combination light signal. The combination light signal is converted into an electrical signal, the amplitude of the electrical signal as a function of time being proportional to the combination-light-signal power as a function of time.

Abstract: The invention is a vibratory rotation sensor comprising a resonator and a housing to which the resonator is attached and a method for reading out the standing-wave orientation angle utilizing a tracking angle which is maintained equal to the orientation angle on average. The resonator is a rotationally-symmetric thin-walled object that can be made to vibrate in a plurality of standing-wave modes. The method includes applying driving voltages to housing electrodes and determining the orientation of a standing wave by performing operations on the resonator signal that arrives at a single resonator output port from one or more electrodes in close proximity to the housing electrodes. A driving voltage may include either a pair of excitation voltages or a forcing voltage or both. An excitation voltage has essentially no effect on the resonator dynamics but carries information pertaining to the tracking angle and the standing-wave parameters when it arrives at the resonator output port.

Abstract: A pulse detector achieves high accuracy over a wide dynamic range in providing accurately spaced pulse edge markers that allow measurement of pulse to pulse time intervals. Received input pulses are transformed to a Gaussian like waveform and a single cycle AC signal having a first polarity initial half cycle is derived therefrom, accomplished by subtracting the Gaussian like waveform from a delayed, but substantially time overlapping, copy of that waveform. Upon completion of that initial half cycle, a pulse edge marker is generated. By measuring the time between the pulse edge marker obtained from one inputted pulse and that of the next, a measurement of the pulse to pulse interval is achieved that is of one nanosecond in accuracy.

Abstract: A all-plastic ZIF (zero insertion force) electrical connector offers the advantages of low cost and ease of manufacturing inherent to plastic. According to a first embodiment of the invention, an all-plastic ZIF electrical connector has a bias means connected to a first half of the connector for providing a bias force to force the first half of the connector against a PCB (printed circuit board) or other circuitry inserted between the first half and a second half of the connector. According to a second embodiment of the present invention, the all-plastic ZIF electrical connector is attached to a flexible printed circuit which allows a first half of the ZIF electrical connector to be flexed slightly to increase the space between the contact fingers to accommodate insertion of the PCB without the need to force the PCB between the contact-making fingers of the connector when the PCB is inserted into the connector.

Abstract: The invention may include a channel selector for a multiple channel sight. In accordance with one embodiment of the invention, a channel selector may include a support (260) for mounting a deflecting surface (250). A pivot assembly (264) may be coupled to the support (260) to provide an axis of rotation (262). The pivot assembly (264) may include opposed recessed ends (272). A ball (274) may engage each of the opposed recessed ends (272). A holder assembly (276) may engage each of the balls (274). Each holder assembly (276) may include a recessed end (272). At least one of the holder assemblies (276) may be adjustable along the axis of rotation (262) of the support (260) to control a shifting torque of the support (260). In another embodiment of the invention, a pivot shaft (118) may be fixably coupled to a support (114) to provide an axis of rotation (116). The pivot shaft (118) may include opposed ends (120).

Abstract: A gas mixing pressure regulator for a closed circuit breathing apparatus comprises a first inlet to provide pressurized air to the breathing apparatus, a pressure responsive demand valve for opening and closing a first inlet, a second inlet for supplying carbon dioxide-free exhaled air from the breathing apparatus, and a mixing chamber for mixing the pressurized air and exhaled air for supplying breathable air to the breathing apparatus. The demand valve is isolated from the mixing chamber by a check valve injector nozzle to prevent contamination thereof and is responsive to pressure demands from the breathing apparatus to ensure reliability, stability and long life.

Abstract: The present invention is a method and apparatus for detecting torpedo guidance system failures which are likely to cause the torpedo to make a circular run. The method consists of measuring the yaw-axis angular velocity of the torpedo and comparing this measurement with a computed estimate of the yaw-axis angular velocity based on measurements of torpedo dynamics other than the yaw-axis angular velocity. If the difference between the measured and computed values exceeds a threshold value, the presumption is that the torpedo is in a circular run and should be destroyed. The invention envisions various levels of precision in computing the estimate of the yaw-axis angular velocity. The various levels of precision involve the measurement of one or more of the group of dynamics parameters consisting of the three components of acceleration and the two components of angular velocity along the pitch and roll axes.

Abstract: Based upon the equation, BIAS.sub.G .alpha. (I.sub.DE -I.sub.COIL).multidot.(V.sub.DE -V.sub.OFF), where BIAS.sub.G is the bias of a multi-oscillator ring-laser gyroscope (14) as induced by gain medium dispersion effects, I.sub.DE is the proper operating coil current, I.sub.COIL is the actual coil current, V.sub.DE is the proper path length control operating voltage and V.sub.OFF is the actual offset voltage, V.sub.DE is matched by path length control offset voltage and/or I.sub.DE is matched by proper coil current, to produce a zero induced BIAS.sub.G. Matching, through dispersion equalization (DE), is effected by use of clockwise (C) and anticlockwise (A) (or counterclockwise) beams traversing paths with a frame (12). The beams are directed to photodetectors (52, 54) and power meters (56, 58).

Abstract: A high voltage flashlamp connector includes a housing having a well formed therein intersecting a flashlamp supporting opening and having a female connector positioned in the well and aligned with the intersecting flashlamp opening. An electrical conductor is attached through the well to the female connector and the well is filled with an encapsulate forming a seat for the housing. The method includes forming the outer shell of the apparatus of a glass-filled polyphenylene oxide having a well and a flashlamp insert opening having an annular groove formed therein and attaching a high voltage electrical conductor to the female connector which is placed in the outer shell well positioned within the flashlamp opening, and cleaning the shell surfaces, and filling the shell with an encapsulate with a mold pin positioned in the flashlamp opening, and then inserting an O-ring seal and attaching a flashlamp.

Abstract: A fiber optic rotation sensor includes a 3.times.3 optical coupler formed of first, second and third optical waveguides. The first, second and third optical waveguides are formed such that the fractions of light coupled from any one of the first, second and third optical waveguides to the other two optical waveguides are constant, independent of thermally-induced changes in the interaction length. An optical signal source provides an input optical signal to the first optical waveguide such that portions of the input optical signal are coupled from the first optical waveguide into the second and third optical waveguides. The optical fiber in which the sensing loop is formed has ends that are coupled to the second and third optical waveguides to receive optical signals that form counterpropagating optical waves in a fiber optic sensing loop and to combine the counterpropagating optical waves after they have traversed the sensing loop.

Abstract: A pad-to-pad connection arrangement between adjacent electrical connectors, such as "bump-to-bump", "bump-to-hollow", or "bump-to-flat" pad arrangements, is achieved. Pads on the surface of an electrical connector may be selectively connected to conductive traces also on the surface of the electrical connector. When two adjacent electrical connectors are joined together in a side-by-side, adjacent relationship, the electrical pads along the side surfaces of the electrical connectors mate, thereby resulting in electrical connections being formed between mated pads of the electrical connectors. According to a preferred embodiment of the present invention, a flexible circuit containing the conductive traces and surface pads is formed about an electrical connector.

Abstract: An electrical surveillance measures system for measuring direction of arrival (DOA), i.e., both azimuth and elevation, of a pulsed or continuous wave radar signal from a moving emitter. Either carrier frequency or pulse repetition interval (PARI) Doppler shift are used whereby the ratio of the Doppler shift is measured by a moving observer. The DOA is measured as a unit vector having basis vectors formed from a linearly independent set of observer's velocity vectors. The DOA unit vector has a linear part where the coefficients of the basis vectors are derived directly from the ratios of frequency or PARI measurements taken in three contiguous dwells. The DOA unit vector has a nonlinear part formed from the requirement that the DOA vector have unit magnitude. The unit vector is resolved in the system coordinates in which emitter azimuth and elevation are defined to allow computation of the latter two values.

Abstract: A sensor coil for a fiber optic gyroscope. A continuous optical fiber is coated with bonding material of predetermined composition such as a thermoplastic material that exhibits a bond strength of at least 100 p.s.i. in tension, equivalent to at least 40 p.s.i. in shear. The coated fiber is arranged into a predetermined winding pattern whereby contacting portions of adjacent coil turns are bonded to one another. Void spaces between contacting portions of bonded turns reduce the volume of bonding material employed (as opposed to a filled potted sensor coil). The coil does not experience the differential in expansion along the axial and radial directions to the degree that has, for example, required the use of single flanged spools in the prior art. Its use with dual-flanged spools permits mounting arrangements that promote coil stiffness, thereby enhancing gyro performance in the presence of vibration.