Patents Represented by Attorney, Agent or Law Firm James R. Yee
  • Patent number: 5521824
    Abstract: A system (102) and method for controlling the operation of an engine test apparatus (104) during a test cycle is provided. The system (102) includes an operator interface (106) for producing a control mode signal and a plurality of setpoints. The system (102) also includes a test controller (108) for receiving the control mode signal and the plurality of setpoints and responsively operating the engine test apparatus. The test controller (108) senses operating characteristics of the engine test apparatus (104). The test controller (108) also selectively operates engine test apparatus parameters in accordance with the control mode signal.
    Type: Grant
    Filed: November 3, 1994
    Date of Patent: May 28, 1996
    Assignee: Caterpillar Inc.
    Inventors: Thomas E. Eagan, William R. Larson, Durwin D. Nigus
  • Patent number: 5520499
    Abstract: The present invention provides a ride control 100 for a machine having an implement and a hydraulic lift cylinder. The hydraulic lift cylinder is adapted for moving the implement to and between a plurality of positions. The ride control is controllable between a RIDE CONTROL ON mode, a RIDE CONTROL OFF mode and a RIDE CONTROL PROGRAM mode. In the RIDE CONTROL ON mode, the ride control connects and disconnects an accumulator from the hydraulic lift cylinder circuit as a function of machine velocity. In the RIDE CONTROL OFF mode, the ride control disconnects the accumulator from the hydraulic lift cylinder circuit. In the RIDE CONTROL PROGRAM mode, the ride control sets the threshold for activation of the ride control to the current machine velocity.
    Type: Grant
    Filed: July 12, 1994
    Date of Patent: May 28, 1996
    Assignee: Caterpillar Inc.
    Inventors: Steven T. Ufheil, Stephen W. Rector
  • Patent number: 5519326
    Abstract: An apparatus (102) is adapted to detect the linear extension (position), velocity and acceleration of a hydraulic cylinder (108). The hydraulic cylinder (108) defines a variable length coaxial resonant cavity (112). Under the control of a controller (228), an RF transmitting section (114) and an RF receiving section (116) are used to determine the resonant frequency of the cavity. The resonant frequency of the cavity (112) is determined by comparing a received signal with a threshold and detecting slope intercept conditions.
    Type: Grant
    Filed: March 14, 1995
    Date of Patent: May 21, 1996
    Assignee: Caterpillar Inc.
    Inventors: Ali A. Bitar, Charles W. Bowman, Denny E. Morgan
  • Patent number: 5509293
    Abstract: A method for dynamically measuring and indicating payload weight for a machine having at least one lift cylinder for elevating a payload carrier is provided. The method includes the steps of lifting a load of known mass during calibrating and sensing a calibration lift cylinder velocity during calibration. To determine payload, lift cylinder hydraulic pressure and lift cylinder extension are sensed during a lifting operation of the machine. A first estimate of the payload is determined as a function of the lift cylinder hydraulic pressure and extension. The method further includes the steps of determining an operating lift cylinder velocity during the lifting operation and determining a velocity correction factor as a function of the calibration lift cylinder velocity and the operating lift cylinder velocity. A second estimate of the payload is calculated as a function of the first estimate and the velocity correction factor.
    Type: Grant
    Filed: December 20, 1994
    Date of Patent: April 23, 1996
    Assignee: Caterpillar Inc.
    Inventor: Arundhati Karumanchi
  • Patent number: 5504839
    Abstract: A synaptic processor for use in a neural network produces a result signal in response to an input signal. The synaptic processor initializes an input expectation and receives an input signal. The synaptic processor determines a net modification to the the input expectation. The net modification to the input expectation has an increase term and a decrease term. The increase term is determined as a function of the input signal. The decrease term is independent of the magnitude of the input signal and is a function of a decay constant. The synaptic processor produces a result signal in response to the input expectation.
    Type: Grant
    Filed: August 29, 1994
    Date of Patent: April 2, 1996
    Assignees: Caterpillar Inc., George E. Mobus
    Inventor: George E. Mobus
  • Patent number: 5491422
    Abstract: An apparatus (102) is for detecting the linear extension (position), velocity and acceleration of a hydraulic cylinder (108). The hydraulic cylinder (108) defines a variable length coaxial resonant cavity (112). Under the control of a controller (228), an RF transmitting section (114) and an RF receiving section (116) are used to determine the resonant frequency of the cavity. The resonant frequency of the cavity (112) is determined by comparing a received signal with a threshold and detecting slope intercept conditions.
    Type: Grant
    Filed: March 14, 1995
    Date of Patent: February 13, 1996
    Assignee: Caterpillar Inc.
    Inventors: Ali A. Bitar, Charles W. Bowman, Denny E. Morgan
  • Patent number: 5471147
    Abstract: An apparatus (102) and method for detecting the position of a piston and piston rod (104,106) within a housing (108) of a hydraulic cylinder (110). The piston (104), piston rod (106), and housing (108) form first and second coaxial resonant cavities (114,116). A first location of the piston and piston rod (104,106) is determined as a function of the resonant frequency of one of the coaxial cavities (114,116). A second location of the piston and piston rod (104,106) is determined as function of the resonant frequency of the other cavity if the first location is invalid.
    Type: Grant
    Filed: October 3, 1991
    Date of Patent: November 28, 1995
    Assignee: Caterpillar Inc.
    Inventors: William E. Allen, Ali A. Bitar, Robert A. Herold
  • Patent number: 5467541
    Abstract: Vehicles (12) having implements (14) are typically used to perform repetitive functions in work cycles. Advantageously, such vehicles (12) include control systems (10) for maintaining a control lever (26) in a predetermined position until an associated work cycle function is completed. The subject control (10) includes a rocker bar (46) connected to the control lever (26) and a solenoid (50) having an actuator rod (52) disposed adjacent the rocker bar (46). The control (10) energizes the solenoid (50) to hold the control lever (26) in the predetermined position in response to a position of the implement (14), a position of the control lever (26), and a desired kickout position.
    Type: Grant
    Filed: September 26, 1991
    Date of Patent: November 21, 1995
    Assignee: Caterpillar Inc.
    Inventors: Robert D. Greer, Daniel E. Henderson, Javad Hosseini, Noel J. Rytter, Gerald P. Simmons
  • Patent number: 5467240
    Abstract: The present invention provides a general purpose driver circuit. The driver circuit is connected to a load. The driver circuit includes a controller for producing a control signal indicative of a desired output current. The driver circuit generates an output current having a magnitude responsive to the magnitude of the control signal. The driver circuit produces a system voltage feedback signal and an output voltage feedback signal and responsively performs output load condition diagnostics.
    Type: Grant
    Filed: September 30, 1993
    Date of Patent: November 14, 1995
    Assignee: Caterpillar Inc.
    Inventors: Gregory L. Williamson, Mark R. Hawkins, William J. Tate
  • Patent number: 5457435
    Abstract: The present invention an apparatus provides a pulse width modulated signal to a load in response to an input signal. The apparatus receives the input signal and a feedback signal, determines a difference between the received signals, integrates the difference, and responsively produces an error signal. The error signal is compared with a reference wave signal and a correction signal is produced. The apparatus produces the pulse width modulation signal by conditioning the correction signal. The apparatus determines the feedback signal by attenuating the pulse width modulation signal in a manner similar to the attenuation caused by the load.
    Type: Grant
    Filed: March 25, 1994
    Date of Patent: October 10, 1995
    Assignee: Caterpillar Inc.
    Inventor: John P. Hoffman
  • Patent number: 5456333
    Abstract: An electrohydraulic control device for a drive train of a vehicle including an engine, a transmission, a source of pressurized fluid, and an input clutch driving connected between the engine and the transmission. The device includes a control lever or handle having a control member progressively manually movable between first and second positions, wherein the transmission is adapted to responsibly shift between a FORWARD and a REVERSE gear ratio in response to movement of the control member from the first position to the second position. An electronic control module is adapted to determine a transmission clutch relative speed as a function of the transmission output speed and the transmission input speed and responsively engage and disengage the input clutch during a directional shift.
    Type: Grant
    Filed: March 25, 1993
    Date of Patent: October 10, 1995
    Assignee: Caterpillar Inc.
    Inventors: Chris D. Brandt, Michael F. Coffman, Randall M. Mitchell
  • Patent number: 5452211
    Abstract: A system and method for estimating the terrestrial position of a vehicle is provided. The system receives electromagnetic signals from a single satellite and responsively produces successive ranges from the satellite to the vehicle and respective successive positions of the satellite. The vehicle's position is determined as a function of the successive ranges and positions.
    Type: Grant
    Filed: August 10, 1992
    Date of Patent: September 19, 1995
    Assignee: Caterpillar Inc.
    Inventors: Christos T. Kyrtsos, Adam J. Gudat
  • Patent number: 5449234
    Abstract: The present invention provides an apparatus for sensing the temperature of surrounding air. The apparatus is thermally isolated from the external environment and more accurately provides an indication of the medium temperature while providing fast response. The apparatus includes a temperature sensing device whose resistance varies with temperature and a conditioning circuit for measuring the resistance and producing an electrical signal which is insensitive to external resistive loading and which has a magnitude responsive to the sensed resistance. The apparatus includes a non-metallic housing which encapsulates the temperature sensitive device and the conditioning circuit. The housing forms a cage portion which surrounds the temperature sensing device and is adapted to protect and to provide air flow to the temperature sensing device.
    Type: Grant
    Filed: November 29, 1993
    Date of Patent: September 12, 1995
    Assignee: Caterpillar Inc.
    Inventors: Gregory H. Gipp, Ronald R. Gustin
  • Patent number: 5442558
    Abstract: The present invention includes a system for estimating the terrestrial position of a vehicle. The system receives electromagnetic signals from a plurality of sources and responsively producing respective ranges from each of said sources to said vehicle and respective positions of each of said sources. The system projects the position of one of said sources to the opposite side of the Earth and responsively determining a projected position and a projected range. The vehicle's position is determined as a function of said ranges and positions.
    Type: Grant
    Filed: August 6, 1992
    Date of Patent: August 15, 1995
    Assignee: Caterpillar Inc.
    Inventors: Christos T. Kyrtsos, Adam J. Gudat
  • Patent number: 5438274
    Abstract: An apparatus (102) is adapted to detect the linear extension (position), velocity and acceleration of a hydraulic cylinder (108). The hydraulic cylinder (108) defines a variable length coaxial resonant cavity (112). Under the control of a controller (228), an RF transmitting section (114) and an RF receiving section (116) are used to determine the resonant frequency of the cavity. The resonant frequency of the cavity (112) is determined by comparing a received signal with a threshold and detecting slope intercept conditions.
    Type: Grant
    Filed: December 23, 1991
    Date of Patent: August 1, 1995
    Assignee: Caterpillar
    Inventors: Ali A. Bitar, Denny E. Morgan, Charles W. Bowman
  • Patent number: 5438517
    Abstract: Systems and methods allow for the accurate determination of the terrestrial position of an autonomous vehicle in real time. A first position estimate of the vehicle 102 is derived from satellites of a global positioning system and/or a pseudolite(s). The pseudolite(s) may be used exclusively when the satellites are not in the view of the vehicle. A second position estimate is derived from an inertial reference unit and/or a vehicle odometer. The first and second position estimates are combined and filtered using novel techniques to derive a more accurate third position estimate of the vehicle's position. Accordingly, accurate autonomous navigation of the vehicle can be effectuated using the third position estimate.
    Type: Grant
    Filed: February 18, 1993
    Date of Patent: August 1, 1995
    Assignee: Caterpillar Inc.
    Inventors: James W. Sennott, Christos T. Kyrtsos, Adam J. Gudat, Dana A. Christensen, Douglas W. Friedrich, Darrell E. Stafford
  • Patent number: 5435131
    Abstract: An apparatus and method for controlling a variable displacement motor of a hydrostatic transmission is provided. The apparatus includes an engine, and a hydraulic pump mechanically coupled to the engine. The variable hydraulic motor includes an output shaft. The apparatus monitors rotational speed of the output shaft. The apparatus and method control motor displacement and detect and/or predict the occurrence of an overspeed condition. The displacement of the motor is modified if an overspeed condition is predicted and/or detected.
    Type: Grant
    Filed: April 11, 1994
    Date of Patent: July 25, 1995
    Assignee: Caterpillar Inc.
    Inventors: Dennis J. Hausman, Stephen W. Rector, David P. Smith, Steven T. Ufheil
  • Patent number: 5430657
    Abstract: The position of a satellite in a satellite based navigation system is determined without reliance on satellite ephemeris data. Orbital parameters are computed for each satellite. The orbital parameters can then be used to predict the position of each satellite at any time. Subsequent ephemeris data may be compared to a predicted satellite position to determine whether the ephemeris data is corrupt. The orbital parameters may be determined by: computing a pseudorange and a velocity for a selected satellite for a plurality of times, computing at least three estimated positions of the satellite from the pseudoranges and velocities, and computing orbital parameters for the satellite from the three estimated positions.
    Type: Grant
    Filed: October 20, 1992
    Date of Patent: July 4, 1995
    Assignee: Caterpillar Inc.
    Inventor: Christos T. Kyrtsos
  • Patent number: 5424623
    Abstract: The present invention provides, an apparatus for controllably moving a vehicle's work implement. The work implement includes a first appendage pivotally connected to the vehicle, and a second appendage pivotally connected to the first appendage. The apparatus senses the geometry of the work implement and responsibly producing a plurality of position signal and produces one of a manual control mode signal and an automatic control mode signal. An operator interface produces first and second lever command signals indicative of desired movement of the work implement. The apparatus receives the one control mode signal and the first and second lever control signals and responsively produces linear motion of the end point of the second appendage along first and second work axes if the one control mode signal is equal to the automatic control mode signal.
    Type: Grant
    Filed: May 13, 1993
    Date of Patent: June 13, 1995
    Assignee: Caterpillar Inc.
    Inventors: William E. Allen, Paul D. Anderson, Walter J. Bradbury, John M. Hadank, Richard B. League
  • Patent number: 5400018
    Abstract: A method for reduces the amount of information relating to the status of a vehicle relayed from the vehicle to a remote location over a communications data link. The method includes the steps of generating a fault code, delivering the fault code to the remote location across the data link, and receiving the fault code at the remote location and responsively generating a data request signal. The data request signal is delivered to the vehicle over the data link, and vehicle information is generated and delivered to the remote location over the data link.
    Type: Grant
    Filed: December 22, 1992
    Date of Patent: March 21, 1995
    Assignee: Caterpillar Inc.
    Inventors: Rolland D. Scholl, David R. Schricker, Satish M. Shetty