Abstract: A multisensor includes a ring-like piezoelectric drive. The ring, which may comprise a closed configuration formed of straight ring segments, surrounds a rotor assembly formed of a pair of rotors, each having a central hub. Vanes extend radially from the central hubs of the rotors to the inner surface of the ring and are fixed to the ring adjacent the intersections of the substantially-straight ring segments. The ring is formed of a laminate of layers of piezoelectric material. Adjacent layers are of opposite piezoelectric polarity whereby an a.c. signal drives the alternating expansions and contractions of pairs of laminated layers.

Abstract: A flexure assembly is provided for coupling and electrically interconnecting the rotors of an inertial multisensor. The rotor assembly is fixed to the base of the multisensor by means of a plurality of outer ring segments that attach to the base. An inner coupling ring is attached at its top and bottom surfaces to trapezoidal spring connectors associated with the rotors. Drive assemblies, each including a pair of radially-directed vanes with paired piezoelectric elements fixed to opposite vane surfaces, are fixed to each rotor. The vanes are connected by trapezoidal connector pieces, which, in turn, connect to the outer ring segments bolted to the base. Radial flexure springs, along with the vanes, are joined to central rotor hubs. Rotor arms also radiate from the rotor hubs. The stiffness of the flexure springs substantially sets the resonant frequency of the coupling flexure assembly that includes the counter-oscillating rotors.

Abstract: An angular rate sensor provides a digital delta theta output signal. A drive member is formed of a single, silicon wafer having a pair of oppositely-facing planar surfaces. The drive member includes a frame and a drive member central portion connected to the frame and arranged to have rotational compliance between the frame and the central portion about an axis perpendicular to the planar surfaces of the silicon wafer. Drive signals are applied to a plurality of electrodes on the central portion to cause rotational oscillation of the drive member central portion about a drive axis perpendicular to the planar surfaces of the silicon wafer. A silicon sensing member is connected to the drive member. The sensing member has a central support member connected to the drive member central portion such that rotational oscillations of the drive member central portion are transmitted to the sensing member central portion.

Abstract: A fastener assembly and a method for making the same wherein a non-fanged fastener is affixed to a retainer by the interaction of a tab and a stake. The fastener assembly preferably includes a retainer having a face with an opening and a tab positioned adjacent to the opening. The tab protrudes from the face and extends over the fastener. A staking die forms a stake which extends into engagement with the retainer such that the fastener is retained to the retainer by the interaction of the tab and the stake.

Abstract: A fastener assembly having improved push-out resistance and bearing engagement characteristics while maintaining serviceability by having stakes located in the sidewall flats. The fastener is mounted in the opening of a retainer and a stake is located in the sidewall. The stake extends from the sidewall and engages the retainer face without disturbing the fastener edge, such that the retainer is retained to the fastener flange by sandwiching retainer between the stake and the flange.

Abstract: A multisensor includes direct rotor coupling. A pair of rotors is mechanically coupled by a torsion bar whose stiffness largely determines the resonant frequency of the counteroscillating rotor pair. The axis of the torsion bar is coincident with the common axis of rotation of the rotors. Piezo bimorphs are fixed to opposed surfaces of radial vanes of the rotors which suspend the torsionally-coupled rotor pair with the case, isolating it from external angular vibration that could interfere with the resonant frequency of the rotor pair subassembly. The bimorphs receive signals for driving the oscillations of the rotors. Taken together, the stiffnesses of the vanes and the torsion bar substantially determine the common resonant frequency of the counteroscillating pair of rotors.

Abstract: A method for translating a virtual address into a physical address, in which page tables used in the translation process are referenced by virtual addresses. Typically, a translation mechanism includes a translation buffer that, given a virtual address, can sometimes provide the corresponding physical address. A translation-buffer miss is said to occur when the translation buffer is presented with an address for which it can not provide the translation. When such a miss occurs, the translation mechanism obtains the translation by reading the page tables. When the translation mechanism attempts to read the page tables from virtual memory, a second-order miss can occur. The difficulty of infinite recursion of misses is avoided by handling second-order misses differently from first-order misses. When a second-order miss occurs, the translation mechanism uses a prototype page table entry and the virtual address of the page table entry to produce a physical address without using the page tables.

Abstract: A heater element assembly for an electric heater, with a first and a second spaced element support. The first spaced element support has a peripheral edge surface and first and second slots extending inwardly from the edge surface, and an aperture therebetween; and a resistive heating element including first and second coiled sections and a connecting section disposed therebetween. The connecting section includes a mediate loop portion, wherein the first and second coiled sections are disposed between and engage the first and second spaced element supports. The connecting section extends through the slots, and the loop portion extends through the aperture, to secure the resistive heating element to the first element support.

Abstract: The present invention relates to an enclosed nut and bolt retainer to protect against the penetration of adjacent objects by the end of the bolt. The retainer is formed by drawing an enclosed pocket from a material, such as metal. The pocket has an opening for receipt of a nut, which is preferably press fit into the pocket. The pocket is deep enough to provide space between the bolt end, when fully threaded into the nut, and the bottom of the pocket. In this way, the bolt is shielded by the pocket enclosure.

Abstract: A sensor for measuring angular rotation rates about three orthogonal axes is based upon sensing Coriolis acceleration forces with a pair of nearly-identical rotors coupled coaxialy by a torsion spring and counter-oscillating in rotation. The torsional oscillator is mounted within a case by means of radial vanes, each comprisig two piezoelectric ceramic plates bonded to a thin metal core responsive to drive signals and providing rotational vibration isolation. The arms of the rotors are designed as piezoelectric open loop accelerometers. Electrodes of selected configurations are mounted to the outer surfaces of the planar members to collect charge indicative of Coriolis accelerations proportional to the angular rotations about the orthogonal axes.

Abstract: An integrated accelerometer includes hinges of silicon composition for securing the strut legs of a pendulous mass to the accelerometer body. Both the body of the accelerometer and the pendulous mass are of metal-coated compositions. Metallized pads are provided on selected surfaces of the hinges for forming eutectic bonds with the body and struts of the pendulous mass of the accelerometer. A heavily-doped continuous region adjacent the surface of the hinge connects the eutectic bonds through a flexure region of reduced thickness to complete necessary device circuitry.

Abstract: A cross member assembly that forms a structural part of a vehicle frame for supporting vehicle components and which consists of an elongated box-like cross bar adapted to have a nut retainer inserted within the crossbar and includes detent members for maintaining the nut retainer in a fixed position relative to the cross bar while at the same time serving to position the nuts on the nut retainer in alignment with bolt openings formed in the cross bar.

Abstract: A thrill-ride apparatus having as a basic concept the revolving of a rider station, whose support provides that the path of the ride will be along an inclined plane. The rider station is fixed to a support arm; and there is no counterbalance as to the weight of the support arm, rider's station, and the rider. The path of the rider is thus such that he must incrementally achieve not only the revolution with respect to the ground and the axis of the support structure, but by such oscillating incremental efforts achieve a raise from "bottom dead center" to "top dead center" as supported by the base of the apparatus.

Abstract: An electrostatically force balanced accelerometer employs electrostatic, single sided square law forcing after filtering and scaling the pickoff signal to determine a restoring force required to bring the pendulous mass (10) of the accelerometer back to its null position. A signal (44,48) proportional to the square root of the restoring force is applied to an electrostatic square law forcing circuit (50) that applies a restoring force to one side or the other of the pendulum (10). A system output signal (42) is proportional to the calculated restoring force, and thus linearly proportional to the sensed acceleration. The transfer function of the forcing circuit (50) is empirically determined by applying a series of known accelerations and measuring the balancing signal required to restore the pendulous mass (10) to its null position.

Abstract: A method for translating a virtual address into a physical address, in which page tables used in the translation process are referenced by virtual addresses. Typically, a translation mechanism includes a translation buffer that, given a virtual address, can sometimes provide the corresponding physical address. A translation-buffer miss is said to occur when the translation buffer is presented with an address for which it can not provide the translation. When such a miss occurs, the translation mechanism obtains the translation by reading the page tables. When the translation mechanism attempts to read the page tables from virtual memory, a second-order miss can occur. The difficulty of infinite recursion of misses is avoided by handling second-order misses differently from first-order misses. When a second-order miss occurs, the translation mechanism uses a prototype page table entry and the virtual address of the page table entry to produce a physical address without using the page tables.

Abstract: A force balanced instrument, such as an accelerometer, employs a pendulous mass having combined electrostatic pickoff and forcing plates on opposite sides thereof. The plates provide a constant attractive force in successive periods acting alternatively on opposing sides of the sensitive element. Force balance is achieved by controlling the duty cycle so that the difference in duration between each of the parts of a full cycle is a linear measure of acceleration. Voltage on each of the forcing plates is sensed independently immediately after each is charged with a fixed charging pulse which provides a fixed force level over the duration of the part cycle. The two successive voltage samples are stored, and the difference between them integrated to control the duty cycle of a pulse width modulator, which itself controls the duration of application of the alternately directed forces applied by the respective plates to the pendulous mass.

Abstract: A three axis inertial measurement unit is shown having a low inertia mechanical oscillator formed from two platforms counterbalanced against each other. Each platform is dithered at its natural frequency about a single torsional axis. A plurality of accelerators are mounted upon at least one of the counterbalanced platforms with each accelerometer having at least an input axis mounted at a predetermined angle to the torsional axis and to the platform. Each platform has a three legged, Y-shaped mounting member with a rotor member positioned between the legs of the mounting member. Web members which form the legs of the mounting member join the rotor member to the Y-shaped mounting member. Additionally, driving webs are mounted on each side of the web members for further joining the mounting member to the rotary member.

Abstract: In a data processing system in which a plurality of data processing units or subsystems exchange logic signal groups by means of a system bus, apparatus is provided to allow sufficient time to permit transients on the system bus to decay, thereby increasing the integrity of the data. When the logic signal groups are applied to the system bus via conducting and nonconducting transistors, the presence of a logic signal on the system bus immediately prior to the application of a set of logic signals from a different data processing unit can delay the on-set of conduction of the most recently activated transistors, thereby resulting in transients of long duration. To accommodate these long transient conditions, the application of the new set of logic signals can be delayed until the transients on the system bus have been attenuated.

Abstract: An inertial measurement unit capable of providing information relating to all six degrees of freedom in an orthogonal three axis system is shown having a mechanical oscillator constructed from two counterbalanced platforms which form a single unit for low inertic rotation about a single torsional axis. Each platform has a Y-shaped rotor member whose legs are positioned between inwardly extending, mounting web members. Driving web members are provided on each side of the mounting web members for rotating the rotor member. A plurality of accelerometers are mounted upon at least one of the counterbalanced platforms. Each accelerometer has an input axis, an output axis, and pendulous axis. Each accelerometer is mounted such that the input axis is at a predetermined angle to the single axis of rotation and the counterbalanced platform. The accelerometers are used to measure angular rate along the pendulous axis and linear acceleration along the input axis.