Patents Represented by Attorney, Agent or Law Firm Robert E. Malm
  • Patent number: 5819304
    Abstract: The invention is a random access memory assembly which is a key component of an object space manager which in turn is a key circuit in a garbage-collecting control unit for a computer system. An object space manager provides the means for deriving pointers to headers of objects from pointers to internal data of objects. The object space manager comprises an encoder that generates an object locator code for each memory cell in which an object is resident, a random access memory assembly for storing the object locator codes for all memory cells in which objects are resident, and an object locator which identifies the memory cell containing the header of an object by means of the object locator code for any memory cell occupied by the object.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: October 6, 1998
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Kelvin D. Nilsen, William Schmidt
  • Patent number: 5815266
    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.
    Type: Grant
    Filed: November 15, 1996
    Date of Patent: September 29, 1998
    Assignee: Litton Systems, Inc.
    Inventors: Samuel N. Fersht, Donald A. Frederick
  • Patent number: 5813865
    Abstract: The apparatus for teaching science and engineering is an interactive multimedia computer system which is used to simulate the performance of scientific experiments on the computer screen. An experiment is a method for determining the value of one experimental parameter by measuring the value of another using an experimental configuration of devices and apparatus. The interactions of the devices and apparatus in the experimental configuration are governed by a relationship among the experimental parameters that define the configuration. The user of the teaching apparatus assembles a pictorial representation of the experimental configuration on the computer screen and interacts with the pictured experimental configuration to simulate the performance of an experiment. The pictured experimental configuration is governed by the same relationship among experimental parameters as the real configuration and thus, the results of the simulated experiment match the results of the experiment performed in the laboratory.
    Type: Grant
    Filed: June 23, 1993
    Date of Patent: September 29, 1998
    Assignee: Iowa State University Research Foundation
    Inventors: Thomas J. Greenbowe, Michelle A. McPhillen
  • Patent number: 5801310
    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.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: September 1, 1998
    Assignee: Litton Systems, Inc.
    Inventors: Anthony Matthews, Guy Thomas Varty, Chung-Ming Li, David Dexter Lynch
  • Patent number: 5790405
    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.
    Type: Grant
    Filed: September 22, 1995
    Date of Patent: August 4, 1998
    Assignee: Litton Systems, Inc.
    Inventor: Robert J. Buchler
  • Patent number: 5778370
    Abstract: The data village system (DVS) comprises an interactive computer system and software that enables a user to establish a data model that defines an organizational structure for an organization's data and that enforces the user's rules as to how the organization's data is manipulated and viewed. The data model for any organization, in its simplest form, consists of tables for receiving related datums, compartments of tables for receiving associated datums, and cables which connect tables thereby indicating linkages between datums in different tables. This basic conceptual underpinning can be expanded to groupings of linked tables into rooms, groupings of linked rooms into houses, and groupings of linked houses into data villages, a data village corresponding to the organization to which the data model pertains. The DVS provides the means for a user to define a data model for an organization in terms of compartments, tables, rooms, houses, and the interconnecting cables.
    Type: Grant
    Filed: August 25, 1995
    Date of Patent: July 7, 1998
    Inventor: Mark L. Emerson
  • Patent number: 5763780
    Abstract: The invention is a vibratory rotation sensor comprising a resonator and a resonator housing and a method for controlling and reading out the sensor utilizing multiplex electronics. The resonator is a rotationally-symmetric thin-walled object that can be made to vibrate in a plurality of standing-wave modes. One or more electrodes are attached to a surface of the resonator and connect to a single output port The housing has a plurality of attached electrodes in close proximity to the resonator electrodes. The method for controlling and reading out the vibratory rotation sensor includes applying driving voltages to the housing electrodes and determining the parameters of the standing waves by performing operations on the resonator signal that emerges from the resonator output port. A driving voltage may include either an excitation voltage or a forcing voltage or both.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: June 9, 1998
    Assignee: Litton Systems, Inc.
    Inventors: Anthony Matthews, J. Scott Darling, Guy Thomas Varty
  • Patent number: 5760304
    Abstract: The invention is a method for applying forces to the resonator of a vibratory rotation sensor (VRS) by establishing an ac voltage between conducting regions of a surface of the resonator and one or more forcer electrodes opposing the conducting regions. The method comprises the steps of generating a first ac voltage having a first frequency and a first phase, generating a second ac voltage having a second frequency, and establishing the difference of the first and second ac voltages between conducting regions of a surface of the resonator and the one or more forcer electrodes. The first and second ac voltages are synchronized to the displacement of a point on the resonator when the resonator is vibrating. The ratio of the vibrational frequency of the VRS to either the difference or the sum of the first and second frequencies is a ratio of integers.
    Type: Grant
    Filed: February 18, 1997
    Date of Patent: June 2, 1998
    Assignee: Litton Systems, Inc.
    Inventor: David Dexter Lynch
  • Patent number: 5757317
    Abstract: The invention is a method for determining the relative position and velocity of a second vehicle with respect to a first vehicle. The method is practiced on board the second vehicle and utilizes a plurality of satellite transmitters and an inertial measurement unit on the second vehicle. The first vehicle has available a plurality of data items consisting of the first vehicle's measured position, measured velocity, and specific-force acceleration. The second vehicle has available data items consisting of the second vehicle's measured position, measured velocity, specific-force acceleration, autonomous position, autonomous velocity, autonomous position correction, and autonomous velocity correction. The measured position and measured velocity are determined utilizing the radio signals from a plurality of satellite transmitters and the specific-force acceleration is obtained from an inertial measurement unit.
    Type: Grant
    Filed: March 17, 1997
    Date of Patent: May 26, 1998
    Assignee: Litton Systems, Inc.
    Inventors: Robert J. Buchler, Kai-Nan Chueh
  • Patent number: 5757316
    Abstract: The invention is a method for obtaining observables for input to a Kalman filter process which determines the attitude (roll, pitch, and heading) of a platform. The invention utilizes an inertial measurement unit (IMU) attached to the platform and an associated processor, a plurality of signal receiving antennas attached to the platform, and a plurality of satellite transmitters. The heading of the platform as determined by the IMU and its associated processor by themselves can be significantly in error. A comparison of the values of an attitude-sensitive function of the ranges from the platform antennas to different groupings of satellite transmitters obtained first by using IMU data and second by using the measured phases of the satellite-transmitter signals received at the platform antennas, a very accurate value for the range function is obtained. This accurate value of the range function is used in a Kalman filter process to obtain very accurate values for platform attitude.
    Type: Grant
    Filed: February 1, 1997
    Date of Patent: May 26, 1998
    Assignee: Litton Systems, Inc.
    Inventor: Robert J. Buchler
  • Patent number: 5725425
    Abstract: A motor vehicle ventilation system having a recirculation or air input mode in which when the rate of change of a signal from an outdoor gas pollution sensor exceeds a threshold limit, the system is adjusted to the recirculation mode.
    Type: Grant
    Filed: August 29, 1996
    Date of Patent: March 10, 1998
    Assignee: Auto Electronics Corporation
    Inventors: Hanns Rump, Norbert Pieper, Jorg Hiller, Olaf Kiesewetter
  • Patent number: 5712427
    Abstract: A vibratory rotation sensor that utilizes non-capacitive mechanical displacement detectors (24) to detect the flexural standing wave pattern in a hemispherical resonator (14). In a preferred embodiment, a plurality of tunneling transducers (24) are positioned around the hemispherical resonator (14) to detect the standing wave. A "force-to-rebalance" mechanization mode is preferably used for calculating the sensor's rate of rotation, with a transducer (24) placement that allows for constant calibration of the sensor's scale factor. In addition, a pickoff transducer orientation is provided that allows for simultaneous calculation of the sensor's rotation angle and any linear acceleration that is exerted on the sensor's hemispherical resonator (14), thereby allowing the sensor to be simultaneously used as a rotation sensor and an accelerometer.
    Type: Grant
    Filed: March 24, 1997
    Date of Patent: January 27, 1998
    Assignee: Litton Systems Inc.
    Inventor: Anthony Matthews
  • Patent number: 5708206
    Abstract: The invention utilizes a sensing body having a non-zero product of inertia to sense acceleration when spun about the y'-axis of an x'-y'-z' Cartesian coordinate system. The product of inertia is computed with respect to an x-y-z coordinate system fixed in the sensing body, the z-axis being in the x'- z' plane, they and y' axes being aligned in the absence of acceleration. The sensing body is pivotally attached to a platform and pivots about an axis parallel to the z-axis. A torquing device applies a torque about the z-axis to the sensing body sufficient to cause the angle between the y-axis and the y'-axis to be zero in the absence of acceleration when the sensing body is being spun at predetermined rate. The accelerometer also includes an orientation sensor which provides a measure of the angle between the y-axis and the y'-axis. A drive assembly rotates the platform about the y'-axis.
    Type: Grant
    Filed: October 11, 1996
    Date of Patent: January 13, 1998
    Assignee: Litton Systems, Inc.
    Inventors: Richard S. Anderson, Roger Burlingame, Jed C. Ludlow, Brian Norling
  • Patent number: 5692185
    Abstract: The garbage-collecting memory module (GCMM) functions much like traditional memory in a computer system, thereby permitting the invention to be utilized with a wide variety of computers. It differs from traditional memory in that it automatically cleanses itself of garbage while functioning as traditional memory without causing excessive delays in the execution of application programs by an associated computer. The GCMM can be designed to interface with a computer system via a traditional memory bus and to communicate with the central processing unit (CPU) of the computer using standard communication protocols. The GCMM is comprised of a memory, a means for communicating with the CPU, and a garbage-collecting control unit. The garbage-collecting control unit gives top priority to satisfying the computer's requests for memory services. The collection of garbage takes place during the intervals between memory service requests.
    Type: Grant
    Filed: January 29, 1996
    Date of Patent: November 25, 1997
    Assignee: Iowa State University Research Foundation, Inc.
    Inventors: Kelvin D. Nilsen, William Schmidt
  • Patent number: 5687368
    Abstract: The CPU-controlled garbage-collecting memory module (CPU-C GCMM) is essentially an intelligent memory that connects to a central processing unit (CPU) and performs the routine and repetitive tasks associated with a spectrum of garbage-collecting techniques under the direction and control of the CPU. The CPU-C GCMM performs its garbage-collecting tasks as background tasks to be performed when the CPU-C GCMM is not burdened with the ordinary fetch and store operations necessitated by the application programs being run on the CPU. The CPU-C GCMM can be structured in a variety of ways. One species which embodies the essence of the invention includes a memory and a memory controller which provides the means for reading data from and writing data to the memory. The memory controller receives fetch requests directly from the CPU and returns the requested data immediately even though the data may be incorrect in certain instances.
    Type: Grant
    Filed: July 22, 1994
    Date of Patent: November 11, 1997
    Assignee: Iowa State University Research Foundation, Inc.
    Inventor: Kelvin D. Nilsen
  • Patent number: 5676545
    Abstract: The invention is a method and apparatus for embedding an implant of a special design in bone tissue in a way that encourages bone tissue growth in and around the implant thereby achieving greater attachment security over longer periods of time. The user employs a bone-fragment collecting drill to form the bone-tissue hole and deliver the resulting bone fragments to a collecting region. The user crumbles the bone fragments by placing them in the lower of two mating spoon-shaped jaws of a pliers-like device and repeatedly opening and closing the jaws until the bone fragments are crumbled. The surface of the implant is equipped with screw threads, one or more embedded helical channels, and through-holes to permit bone growth into the implant. The installation of the implant consists of partially filling the bone-tissue hole with bone crumbs, packing the helical channels and through-holes with bone crumbs, and screwing the implant into the bone-tissue hole.
    Type: Grant
    Filed: April 19, 1996
    Date of Patent: October 14, 1997
    Inventor: Shedrick D. Jones
  • Patent number: 5668908
    Abstract: A fiber optic gyro sensor coil with improved temperature stability for use at temperatures between T1 and T2, T1 being less than -30.degree. C. and T2 being greater than 60.degree. C. The coil is wound with an optical fiber having one or more jackets. The one or more jackets are made of materials having glass transition regions outside the temperature range from T1 to T2.
    Type: Grant
    Filed: December 22, 1995
    Date of Patent: September 16, 1997
    Assignee: Litton Systems, Inc.
    Inventor: Amado Cordova
  • Patent number: 5657025
    Abstract: The integrated GPS/inertial navigation apparatus utilizes satellite signals received with two spatially-separated antennas to achieve improved heading estimates for a mobile platform. Each satellite signal comprises one or more component signals with each component signal having a different carrier frequency. The integrated GPS/inertial navigation apparatus consists of a receiver and an inertial navigation system. The receiver measures the carrier phase of each of one or more component signals of one or more satellite signals received by each of the two antennas during successive time periods of duration T.sub.p. Phase measured during a T.sub.p time period is called T.sub.p -phase. Only one component signal of one satellite signal received by one antenna is measured during any T.sub.p time period. The receiver utilizes the T.sub.p -phases of each component signal obtained during a T.sub.k time period to estimate the phase of the component signal at the end of the T.sub.
    Type: Grant
    Filed: August 7, 1995
    Date of Patent: August 12, 1997
    Assignee: Litton Systems, Inc.
    Inventors: Robert E. Ebner, Ronald A. Brown
  • Patent number: 5633791
    Abstract: The double modulation converter (DMC) is a DC-AC converter for driving an AC-DC converter. It has two input terminals for connection to a DC voltage source, two output terminals for connection to an AC-DC converter, and a plurality of circuit control terminals for receiving a plurality of control waveforms which cause a bipolar stream of width- and amplitude-modulated pulses to appear at the output terminals when a load is connected across the output terminals. The basic elements of the DMC are two switches connected in series across the input terminals. One output line connects an output terminal to the junction of the two switches. The other output line connects the other output terminal to one of the input terminals. During operation, the two switches periodically and alternately open and close, the closure of one switch causing a pulse of one polarity to appear across the output terminals, and the closure of the other switch causing a pulse of opposite polarity to appear across the output terminals.
    Type: Grant
    Filed: April 26, 1995
    Date of Patent: May 27, 1997
    Inventors: Franki N. K. Poon, Bryan M. H. Pong
  • Patent number: 5604311
    Abstract: A monolithic Coriolis rate sensor includes a first member and a vibration generator that causes the member to vibrate along a first direction. At least one other member is mechanically coupled to the first member so that orthogonal vibrational modes are coupled to the other member when the members are rotated about a rotation axis. The vibrational mode coupling occurs as a result of the Coriolis effect. A vibration sensor is used to sense the orthogonal vibrational modes, the amplitude of which determines the rate at which the members are rotated. In a preferred embodiment, a central and two transverse end members with substantially equal resonant frequencies are mechanically coupled to form an "I"-shaped structure. The center member is vibrated at its resonant frequency, and orthogonal vibrational modes are coupled to the end members when the structure is rotated about a rotational axis that is orthogonal to both vibration directions.
    Type: Grant
    Filed: June 7, 1995
    Date of Patent: February 18, 1997
    Assignee: Litton Systems, Inc.
    Inventors: Lalit Kumar, Arthur R. Voros