Abstract: In a self-propelled vehicle such as a shoulder-fired missile, a bidirectional data interface between a missile processor and an external apparatus includes a pair of function signal paths which extend partly outside the missile. A first component of the interface uses one of the signal paths to couple reprogramming information to the missile processor in response to a prompt from the processor. A second component of the interface responds to a periodic signal on the second signal path to receive missile processor data which the missile processor connects to the first signal path in synchronism with the periodic signal.

Abstract: A method of forming high temperature resistant coatings having magnetic particles in a ceramic matrix by plasma spraying. Typically, the surface to be coated is cleaned by a combination of solvent cleaning and abrasion, such as by grit blasting. A mixture of ceramic particles and metal particles is provided and the mixture is plasma sprayed onto the surface using a sufficiently large proportion of metal particles to form a conductive first coating layer. A second layer is plasma sprayed with a mixture having a gradually decreasing metal particle content. A third layer is plasma sprayed using a mixture having a sufficiently low proportion of metal particles as to be dielectric. A pattern of small, spaced, conductive areas is then formed on the surface of the third layer. The resulting coating is durable, high temperature resistant and absorbs incident microwave energy.

Abstract: A composite bobbin (10) for use in an optical fiber canister has a surface with a spirally groove base layer (38) in which the first layer of an optical cable (42) is wound. The base layer (38) is prepared by coating the external surface of a central portion (12) of the bobbin (10) with an adhesive layer (16) of a curable two-stage epoxy, winding a tensioned wire (22) in a spiral pattern along the length of the central portion (12), and heating the bobbin (10) to cure the epoxy. The proper combination of tension and curing cycle permits the grooves of the base layer (38) to be formed to a depth of about 1/3 of the diameter of the optical cable (42).

Abstract: An improved feed waveguide 15 for an antenna 10 is disclosed which reduces coupling junction phase errors. The improved feed waveguide 15 of the present invention includes first and second slotted parallel walls 35a and 37a along the length thereof. The first wall 35a includes a first elongate slot 27 therethrough having a first longitudinal axis 42. The second wall 37a includes a second elongate slot 32 which is located on the second wall 37a opposite the first slot 27 on the first wall 35a. The second slot 32 has a longitudinal axis 44 which is orthogonal to the longitudinal axis 42 of the first slot 27.

Abstract: Method and apparatus for making a filament winding amenable to inside payout and having squared-off ends providing optimal volumetric efficiency. The filament crossovers are distributed so as to reduce crossover stacking in one or a few places which can interfere with winding and payout from the finished winding. A base wire layer is wrapped onto a mandrel over which a guide is nestingly wound with adjacent guide wire turns spaced apart. The filament first layer is wound nesting in the guide wire spaces, and subsequent filament layers accordingly formed. Each crossing filament turn has an advance in a crossing region substantially aligned with a crossover region in the underlying layer and which in one embodiment is one-half the winding pitch.

Abstract: An optical fiber (22) is tested for payout properties by supporting it on a payout support (24 ), preferably in the form of a hollow frustum of a cone, and attaching an unsupported end (26 ) of the optical fiber (22) to a projectile (42) that is thereafter propelled rapidly by expanding gas. The expanding gas is preferably generated explosively or by pressurizing the rearward end of the stationary projectile (42) and then releasing the projectile (42). A pneumatic gun (40) suitable for such testing has a barrel (44) sufficiently large to receive the projectile (42), a latching mechanism (60) that releasably engages the projectile (42), a closure (50) at the rearward end of the barrel (44) with a bore (58) therethrough concentric with the axis of the barrel (44) through which the optical fiber (22) passes and is drawn. The pneumatic gun (40) further includes a gas reservoir (48) that supplies a pressurized gas to the back side of the projectile (42).

Abstract: A bobbin (50) includes a substantially cylindrical bobbin support (52), formed of a structural material such as aluminum or graphite-epoxy composite material, and an overlying sleeve (58) that slides on the bobbin support (52), formed of a material having a longitudinal coefficient of thermal expansion matched to that of the longitudinal coefficient of thermal expansion of an optical fiber pack (66) wound upon the sleeve (58). One end of the sleeve (58) is fixed to the corresponding end of the bobbin support (52). The expansion coefficient of the sleeve material is preferably at least about 50.times.10.sup.-6 per degree F., to more closely match that of the fiber pack in the direction perpendicular to the fibers.

Abstract: A method and circuit for measuring direct and high duty factor current in a conductor (1) with minimal interference with the operation of a monitored circuit. Current flow in the conductor is magnetically sensed with a transformer T1 having a primary winding connected electrically in series with the conductor (1). The transformer T1 is driven into saturation during a first time interval and brought out of saturation during a second time interval. After the transformer T1 is brought out of saturation, an output signal is provided which is proportional to the flow of current in the conductor (1).

Abstract: A convoluted fan structure is provided along the bottom surface of each diagonal segment of a petal-formed aft cover for a missile canister. As the cover petals open under influence of rocket exhaust impingement on the cover, the fan structures cover the diagonal areas toward the corners of the opening. This prevents recirculation of rocket exhaust gases from the plenum into the canister through the formerly open corner areas and augment the closure force to restore the petals to the closed position after completion of missile launch.

Abstract: A portable missile launcher has an optical system with a single lens (22) for receiving visible and near infrared light energy from a target (14) directing it to a prism (24) where the light is split into a part transmitted to an eyepiece (28) and a further part (30) to infrared tracking equipment (18). The objective lens (22) is a doublet having a front lens (32) and a rear lens (41) which cooperate to provide sufficiently small chormatic aberration to enable image quality correction for both visual examination and near infrared tracking.

Abstract: A figure eight linear dispenser (10) having an optical fiber winding configuration adapted to dispense an optical fiber waveguide (14) at high speed. The dispenser (10) is built up of a series of flat winding layers, with each layer comprising an interlaced figure eight pattern. More particularly, the dispenser (10) comprises a housing having a pair of bobbins (12a, 12b) respectively centered on a pair of half-circular outer guides (13a, 13b). The optical fiber waveguide (14) is wound around the bobbins (12a, 12b) inside the outer guides (13a, 13b) in a series of layers (15a-15e) of figure eight loops (16a-16e). An optional cover may be disposed over the bobbins (12a, 12b) and the guides (13a, 13b) in order to enclose the waveguide (14). The waveguide pay-out of the dispenser (10) through a properly spaced eyelet (17) is nearly helix-free and linear as a result of cancellation of the angular momentum in the paired figure eight loops (16a-16e).

Abstract: An optical system (10) for portable missile launcher (23) includes an objective lens (12) for receiving the entire visual and near infrared light energy emanating from a target (14) and immediate background of the target. The light energy from the objective lens then passes through a Porro prism assembly (16) which acts to direct visual light along a first path to an eyepiece (20) and near infrared along a second path at approximately a right angle to the first path where it is received by a tracker assembly (22) and monitored. The Porro prism (16) is constructed in accordance with this invention to include a multi-layer interference dichroic coating (18) disposed between the two prisms (34,36) which make up the prism assembly. This coating is of such a nature as to readily permit light energy in the visual range to pass directly through the coating, but at the same time to reflect the near infrared components along a second path bringing them to focus on the tracker assembly (22).

Abstract: A monocular inspection system (10) having a substantial eye relief (62), a large exit pupil, and a line of sight viewing of an object under observation (14). The inspection system (10) includes an objective lens assembly (20) which forms an image of the object (14) and which has an axis coincident with an optical path (66). A prism (16) redirects the optical path (66) to coincide with a viewing axis (64) such that the image is formed in a focal plane intersected by the viewing axis (64). A monocle assembly (40) having an axis coincident with the viewing axis (64) forms an exit pupil for the image.

Abstract: A dewar (20) useful in rapidly cooling a sensor (28) supported thereon includes a bore tube assembly having a cylindrical dewar bore tube (22) with an end cap (24) at one end to close the bore tube (22). The bore tube assembly is cooled by directing a stream of coolant at the interior of the end cap (24). The sensor (28) is mounted directly to the exterior surface of the end cap (24). A cold shield (34) partially encloses the sensor (28). A cold shield support bracket (38) mounts the cold shield (34) to the cylindrical side walls of the dewar bore tube (22) at a mounting location (36) axially displaced from the end cap (24) and therefore less effectively cooled than the end cap (24), so that heat is extracted from the support bracket (38) and the cold shield (34) less rapidly than from the sensor (28). From an uncooled starting condition, the sensor (28) is cooled to its operating temperature, and the cold shield (34) is cooled to its operating temperature, in about the same time.

Abstract: A filament dispenser (18) for a missile data link has a bobbin with end flanges (24, 26) fixedly mounted to the missile (86). A shroud (30) is spaced opposite the filament pack for frictionally engaging a ballooning filament (30) during dispensing to reduce ballooning amplitude. A second version passes the dispensed filament back through an opening (38) in the bobbin for reverse dispensing. A third version is similar to the first version and, in addition, on leaving the bobbin filament (48) passes through a relatively small diameter ring (52). In a fourth version, similar to the second version, the filament (80) passes through a constraining ring (82) located within the bobbin opening (38). In a final version the filament dispensed from a pack (92) passes around a curved end flange (90) then back over a curved surface (106) and through an opening (102) forming two balloons (109, 110) and helix elimination.

Abstract: An optical fiber (12) is removably held in place on a payout bobbin (14) using an adhesive. The adhesive is applied directly to the optical fiber (12) by passing the optical fiber (12) through a pressure-less die applicator (28) that applies a uniform thin layer of adhesive to the optical fiber (12), prior to winding onto the bobbin (14). Winding preferably proceeds continuously within layers, and from layer to layer.

Abstract: An endothermic cooler (10) for electronic components (16) in, for example, a missile (12) includes an enclosure (14) having a thermally conductive coupling to the electronic component. A source of water in a first compartment (28) is segregated from salts in a second compartment (30). The salts are capable of providing an endothermic reaction when mixed in a water solution. The two compartments are segregated from one another by a membrane or conduit (32). The membrane is pierced by a spike (34-2 or 34-3) through an actuating mechanism (36) and the conduit is opened by a valve (34-4). Formation of the solution provides cooling for conduction of heat from the electronic component through a thermally conductive plate (24) and its fins (26).

Abstract: The bobbin of an optical fiber canister is constructed so that the thermal expansion coefficient of the bobbin is matched to that of the optical fiber pack wound upon the bobbin. In one embodiment, an optical fiber canister (20) has a bobbin (22) in the shape of a frustoconical shell (24) with a flange (26) at one end of the shell (24), the bobbin (22) having a slot (34) through the shell (24) and the flange (26) extending longitudinally parallel to the axis (28) of the shell (24). In another embodiment, an optical fiber canister (50) has a bobbin (52) in the shape of a frustoconical shell (54) with a flange (56) at one end of the shell (54), the bobbin (52) being formed of at least two layers (62) of structural fiber (60) material helically wound and adhesively bonded into the shape of the shell (54). The structural fiber (60) material is selected to have substantially the same thermal expansion properties as optical fiber material, and may in fact be optical fiber.

Abstract: A digitally controlled oscillator (100) having a first oscillator circuit (108) for providing an oscillator signal F.sub.o of a defined frequency and a digital divider (110) for dividing the oscillator signal F.sub.o by a selectable number controlled by a digital word for providing a clock signal F.sub.clk. A second oscillator circuit (104) receives the clock signal F.sub.clk and provides a low frequency signal F.sub.c. The second oscillator circuit includes a digitally controlled resonator element (112) for determining the frequency of the low frequency signal and has a center frequency dependent upon the clock signal. Circuitry (118, 120, 138) is included for providing first and second pairs of quadrature phase shifted signals derived from the clock signal F.sub.clk and the low frequency signal F.sub.c and from the oscillator signal F.sub.o, respectively.

Abstract: An optical fiber payout canister (36) comprises a bobbin (42) upon which an optical fiber (34) is wound. A shroud (50) overlies the bobbin (42), and a layer (54) of an ablative material is coated onto at least a portion of the inside wall (48) of the shroud (50) adjacent to the bobbin (42), so that the optical fiber (34) may contact the ablative material (54) during payout. Desirably, the ablative material (54) has a hardness equal to or less than that of the buffer layer of the optical fiber (34). In one embodiment, the ablative material (54) has a composition similar to that of the polymer buffer layer, such as an urethane acrylate. The ablative material (54) removes energy from the optical fiber during payout, and in particular reduces the circumferential component of the energy, permitting the optical fiber (34) to be dispensed through a dispensing opening (58) in an end wall (60) of the shroud (50).