Abstract: Ratiometric transducer and method in which the outputsnal is linearly proportional to the supply voltage or level of excitation. A drive circuit applies a drive signal to an element which undergoes a change in accordance with a condition to be monitored (e.g., rotation or acceleration), and a pickup circuit receives signals from the element and provides an output signal corresponding to the condition to be monitored. Operating voltage is supplied to the drive circuit from a power supply, and the gain of the drive circuit is adjusted in accordance with variations in the operating voltage to make the drive signal and the output signal proportional to the operating voltage.

Abstract: Methods for surface micro-machining silicon wafers, including coating cavity sidewalls with oxidation-resistant material to prevent lateral oxidation. This in turn prevents "bird's beak" during formation of a diaphragm. The methods are useful for, among other things, the manufacture of absolute-type pressure sensors. Along with bulk micro-machining techniques, the methods can be used to produce gauge- and differential-type pressure sensors, as well.

Abstract: A closed-ended linear voice-coil actuator in which the effects of armature reaction are significantly reduced. The actuator includes a housing formed from longitudinal field plates and end plates which are connected together. A cylindrical or rectangular core of ferromagnetic material is mounted inside the housing with its ends connected to the end plates. Permanent magnets mounted on the field plates are used to produce a transverse magnetic field. A coil of wire is wound around a coil bobbin. The coil of wire and coil bobbin are disposed around the core and are free to move along its length. A coil mounting bracket is mounted to the coil winding to allow the user of the voice-coil actuator to attach a load. A hole is drilled through the core, thereby removing some of the ferromagnetic material of which the core is composed. By placing the hole at the center of the core where the magnetic field due to the permanent magnets is minimal, the field produced by those magnets remains substantially the same.

Abstract: A diaphragm is disposed over a cavity formed in a silicon base. A plurality of electrodes are radially disposed about the diaphragm overlying the cavity, and a signal applying circuit applies a signal to the plurality of electrodes so that portions of the diaphragm flex for establishing a net angular momentum (e.g., the flexing of the diaphragm simulates a circumferentially traveling wave). A deformation sensing circuit comprising a plurality of strain gages interconnected to form a corresponding plurality of Wheatstone bridges are disposed about the periphery of the cavity along orthogonal axes for sensing deformation of the structure about the orthogonal axes.

Abstract: A diaphragm is disposed over a cavity formed in a silicon base. A plurality of electrodes are radially disposed about the diaphragm overlying the cavity, and a signal applying circuit applies a signal to the plurality of electrodes so that portions of the diaphragm flex for establishing a net angular momentum (e.g., the flexing of the diaphragm simulates a circumferentially traveling wave). A deformation sensing circuit comprising a plurality of strain gages interconnected to form a corresponding plurality of Wheatstone bridges are disposed about the periphery of the cavity along orthogonal axes for sensing deformation of the structure about the orthogonal axes.

Abstract: Digital FM demodulator and method in which zero-crossings of a frequency modulated input signal are detected, a binary pulse is provided for each of the zero-crossings, and the binary pulse stream is filtered digitally to provide enhanced resolution of the incremental phase (frequency) of the input signal over a period which is asynchronous with the input signal. In the disclosed embodiments, the digital filtering is done with comb decimation filters, with a higher order filter being employed where greater resolution is desired.

Abstract: The method of making the casing comprises the steps of preparing a powder mixture consisting predominantly of a metal powder mixed with a minor proportion of graphite powder ranging from about 0.2% to about 2%, preferably 0.8% by weight, while the metal powder ranges from about 99.8% to about 98% by weight. The powder material is compressed into a casing mold to a molded density ranging from about 0.21 to about 0.24, preferably 0.23 of a pound per cubic inch. The molded powder is sintered in an inert atmosphere at a temperature ranging from about 1500 to about 1700, preferably 1600.degree. F. for a time sufficient to unite the molded powder into a brittle porous frangible casing. The graphite powder vaporizes and escapes from the molded casing during the sintering step whereby porosity and frangibility are imparted to the casing.

Abstract: The joint construction is employed between a military rocket motor and a warhead adapted to be propelled by the motor. The motor includes a motor tube with a cylindrical front portion having an internal cylindrical surface therein. The warhead comprises an adapter ring having a cylindrical rear portion with an external cylindrical surface which is telescopically receivable within the internal cylindrical surface. The internal and external cylindrical surfaces are formed with respective confronting aligned internal and external helical screw thread grooves for receiving a fusible substantially helical joint member to form a secure connection between the rocket motor and the warhead. The helical joint member is made of a material having a low melting temperature, preferably a eutectic metal alloy, whereby the heat of a fire or the like will melt the joint member to disconnect the warhead from the rocket motor. The motor tube has a front wall with a vent opening therein, normally closed by a plug member.

Abstract: The ignition safety device is mounted on a rocket motor nozzle having a body with a longitudinal nozzle opening having an igniter therein for igniting the propulsion charge of the rocket motor. An electrically operable detonator is mounted in a detonator opening in a housing mounted in the body. An actuator and a locking member are movable in the body between safe and armed positions. The locking member has means operative in its safe position for locking the actuator. Movement of the locking member to its armed position unlocks the actuator. A spring biases the locking member to its safe position. The actuator is adapted to operate a switch which initially short circuits the electrically operable detonator but is operable by the actuator to an armed position in which the detonator is no longer short circuited and is connected to an electrical input circuit including a contact band on the nozzle body.

Abstract: A cylindrically-symmetrical moving coil linear actuator utilizes axially-magnetized cylindrical magnets to provide flux-focused interleaved magnetic circuits. The moving coil linear actuator includes a cylindrical shell that has a closed end and open end. A magnetic core is disposed within the shell to define an annular air gap between the shell and the core. The core includes a first set of axially-magnetized cylindrical permanent magnets having a first direction of magnetization and disposed in proximity to the closed end of the shell. A second set of axially-magnetized cylindrically permanent magnets has a second direction of magnetization which is opposite of the first direction of magnetization and is disposed in proximity to the open end of the shell. A first ferro-magnetic pole piece is disposed between the first set of magnets and the second set of magnets. A second ferro-magnetic pole piece is disposed between the second set of magnets and the open end of the shell.

Abstract: The projectile, adapted to be fired from an automatic cannon, comprises a frangible porous brittle generally cylindrical casing having a tapered nose portion and made of a molded sintered powder material preferably consisting predominantly of 60 to 100% type 316 stainless steel powder, the remainder being pure iron powder. The rear end of the casing is formed with an axial bore wherein a hard dense penetrator rod is received, preferably made of tungsten or tungsten carbide. Behind the penetrator rod, the casing has an enlarged bore wherein an incendiary pellet is received, preferably comprising zirconium crystals molded in an epoxy matrix. A massive closure plug closes the enlarged bore behind the incendiary pellet. Upon impact with a target, the frangible casing disintegrates into granular fragments while the penetrator rod punches a hole in the target through which the fragments are propelled.

Abstract: A silicon chip is micromachined so that a plurality of tines extend radially and coplanarly from an outer peripheral surface of a circular base. First and second mounting members extend from the base for mounting the base to a support. The first mounting member is disposed generally perpendicularly to the second mounting member. A pulse generator applies electrostatic or electromagnetic pulses to successive free ends of the plurality of tines so that each tine momentarily vibrates in the plane in rotational sequence along the circumference of the base. The successive vibrations establish a net angular momentum approximating a spinning wheel so that rotation of the sensor about the axis of one of the first or second mounting members causes the other mounting member to experience a deformation due to coriolus force.

Abstract: An optical apparatus for sensing the motion of an object. A light source transmits light through a first and second optical fiber. The first and second optical fiber are positioned on opposite sides of a modulator or code disk to face each other along an optical path. The modulator has alternating reflective regions and transmissive regions which modulate the light propagating along the optical path as the modulator moves across the optical path. The modulated light is received by the first and second and optical fibers and transported to a predetermined location for evaluation.

Abstract: A flechette is disclosed comprising a rod-shaped steel body having a blunt generally conical penetrating point, a separate resinous plastic fin component securely mounted on the rear end portion of the body, and a generally conical gradually tapering resinous plastic nose piece securely mounted on the penetrating point for reducing air drag when the flechette is fired at high velocity. Interlocking annular flanges are formed on the penetrating point and the nose piece for securing the nose piece to the body. The fin component has an axial sleeve received around a rear pin portion of the body and securely retained thereon by annular flange and groove members on the sleeve and the rear pin portion. A modified flechette is disclosed having a separate, hardened steel penetrator component securely mounted on a reduced front pin member on the body by a press fit between the front pin member and a rearwardly opening bore in the penetrator component.

Abstract: The safe and arming device comprises a housing containing a setback weight movable rearwardly against the resistance of springs in response to forward acceleration of the housing. A fire tube in the housing has a fire tube opening, blocked initially by first and second swingable inertial arming lugs. The weight carries a pin having a first portion initially received in a first opening in the first lug for retaining it in its safe position. The setback of the weight withdraws the first pin portion from the first opening. Spin acceleration causes swinging of the first lug to its arming position wherein a detonator on the lug is aligned with the fire tube opening. The lug has a second opening for receiving a second pin portion when the weight is spring-returned after cessation of the acceleration, whereby the lug's arming position is maintained. The second lug has a third opening for receiving a third pin portion to maintain the safe position of the second lug.

Abstract: The projectile, adapted to be fired from an automatic cannon, comprises a frangible porous brittle generally cylindrical casing made of a molded sintered powder material preferably consisting predominantly of 60 to 100% type 316 stainless steel powder mixed with pure iron powder ranging from 40% by weight to zero. The powder material initially includes graphite powder ranging from about 0.2% to 2% by weight. The powder material is compressed into a casing mold to a molded density ranging from about 0.21 to about 0.24, perferably 0.23 of a pound per cubic inch. The molded powder is sintered in an inert atmosphere at a temperature ranging from about 1500 to about 1700, preferably 1600.degree. F. for a time sufficient to unite the molded powder into a brittle porous frangible casing. During sintering, the graphite powder vaporizes and escapes whereby porosity and frangibility are imparted to the casing.

Abstract: An optical code track supporting structure for providing position data about a moveable object. The encoder has an outside portion and an inside portion connected by a series of evenly spaced spokes which form a clear index track which allows substantially all of a light beam to be transmitted therethrough. The index track also has a single index element located therein which fully blocks the light beam for one brief pulse during one cycle of the moveable object.

Abstract: A fiber optic probe sensor for accurate measurement of displacement of a target over very small distances is disclosed. The probe sensor is comprised of plurality of light emitting fibers exclusively occupying a central region and connected to a light source for illuminating the target; a first and second plurality of light receiving fibers arrayed in two concentric regions exterior to and at two different distances from the central region, and means for measuring reflected light received from the target and for generating an output proportional to the light received and independent of target reflectivity or light source variation.

Abstract: An improved design for an optical encoder with a compensation feedback signal for compensating for effects of time and temperature on the photoemission characteristics of the encoder's light source. By using a current mirror, the photodiodes which normally provide only the data signal now provide both the data signal and the compensation feedback signal, thereby eliminating the need for a separate, dedicated photodiode for the compensation feedback signal. This results in eliminating the necessity of matching the electrical operating characteristics of the data photodiodes to those of a compensation feedback photodiode. This further results in eliminating the large die area required for including a compensation feedback photodiode in an integrated circuit design.

Abstract: An apparatus and method are disclosed for indicating the angular position of an object relative to a reference position in which a plurality of different tracks of indicia are positioned on indicia-supporting media that is adapted for movement with the object. High resolution position words are assembled by merging position information resolved from a plurality of different tracks of indica. The position information is resolved by way of sine wave synthesis in which position information from a pair of tracks having different resolutions is used to generate position information of an intermediate resolution. This intermediate position information is merged with position information from the higher resolution track of the two tracks.