Abstract: A vehicle anti-lock braking system includes a brake pedal and a brake modulator. The brake system reduces braking pressure by an initial pressure reduction after detecting insipient wheel lock. Vehicle deceleration is measured as a function of brake pedal position. A first table is updated with the vehicle deceleration and the brake pedal position. A coefficient of friction of a road surface is estimated based on the first table. Wheel slip and deceleration target thresholds are determined based on the coefficient of friction. The wheel slip and deceleration target thresholds are used to populate a command table for the anti-lock braking system. Brake heat, brake torque, vehicle weight and grade are estimated. Release and apply pressures are calculated from an adjusted coefficient of friction, a coefficient of friction and the grade.
Type:
Grant
Filed:
June 26, 2002
Date of Patent:
March 9, 2004
Assignee:
General Motors Corporation
Inventors:
Allen John Walenty, Kevin Gerard Leppek, David Alan Thatcher
Abstract: An electric traction motor for a vehicle including a housing, a wound stator field located in the housing, a rotor magnetically interacting with the wound stator field, high energy magnets configured in the rotor, and low energy magnets configured in the rotor.
Abstract: A method and apparatus compensates throttle area in an engine control system with an electronic throttle using intake diagnostic residuals. A plurality of tables relate throttle area, breakpoint numbers, flow loss factors and residual values. At least one of the tables is updated based on the intake diagnostic residuals to generate a compensated throttle area.
Abstract: A control system for controlling the displacement of a variable displacement internal combustion engine including measuring a variable indicative of torque for the variable displacement internal combustion engine, generating a torque threshold that indicates a torque condition to vary the displacement of the variable displacement internal combustion engine, and characterizing driver behavior to determine the torque threshold.
Abstract: A method of fabricating a rotor for an electric traction motor including the steps of forming cavities in the rotor, injecting magnetic material in a portion of the cavities, injecting nonmagnetic material in a portion of the cavities, and post-magnetizing the magnetic material.
Type:
Grant
Filed:
September 14, 2001
Date of Patent:
February 3, 2004
Assignee:
General Motors Corporation
Inventors:
Khwaja M. Rahman, Peter James Savagian, Francois J. Biais, Constantin C. Stancu
Abstract: A tire deflation warning system is based solely on the measured distance traveled by each tire of a: vehicle. The vehicle is equipped with a sensor which generates pulses representative of the distance traveled by each wheel such as generated by an ABS brake system. The system accumulates the pulses in the controller to determine whether the vehicle is stable. If the vehicle is stable, it performs a test to cover individual tires, opposing diagonal tires or any combination of three tires using an average of the diagonal ratio. These tests are performed by utilizing the pulses generated by each wheel representing the distance traveled by the wheel.
Abstract: A method and apparatus for fabricating a rotor for an electric traction motor including forming cavities in the rotor, injecting magnetic material in a portion of the cavities, configuring an electrical winding in a portion of the cavities, and post-magnetizing the magnetic material.
Abstract: An energy-saving method for operating a climate control system includes reporting an ambient outside temperature from a first temperature sensor to a controller unit and reporting a climate control air temperature from a second temperature sensor to the controller unit. The control unit performs an algorithm to define a control criterion value in response to the ambient outside temperature. A non-refrigeration cycle based heating element is activated to provide heated air to an interior surface of a windshield if the climate control air temperature is above the control criterion value. Moreover, a refrigeration cycle based cooling element and the non-refrigeration cycle based heating element are activated to provide the heated air to the interior surface of the windshield if the climate control air temperature is at or below the control criterion.
Abstract: An improved method of assessing the catalyst warm-up rate of a motor vehicle catalytic converter is based on the response rates of fast warm-up exhaust gas sensors located in the exhaust gas upstream and downstream of the catalytic converter. The method essentially measures an oxygen storage characteristic of the catalyst that increases as the catalyst temperature rises to its ideal operating temperature. In one method, a ratio of switching frequency between the upstream and downstream exhaust gas sensors is periodically computed and compared to a threshold during catalyst warm-up. In another method, the response times of the exhaust gas sensors to a known air/fuel ratio transition are detected to form a measure of the oxygen storage characteristic that is compared to a threshold. In each method, the threshold varies as a function of cumulative airflow through the engine to compensate for different engine airflow levels.
Abstract: A vehicle engine control system controls an engine that includes a plurality of cylinders and that generates exhaust gas. An air-assisted direct injection fuel system supplies an air/fuel mixture to the cylinders. A catalytic converter reduces harmful emissions from the exhaust gas after the catalytic converter reaches a light-off temperature. A controller communicates with the engine, the catalytic converter and the air-assisted direct injection fuel system. The controller optimizes cam phasing, the air/fuel mixture and spark angle for full and partial engine operating modes. The controller deactivates at least one of the cylinders of the engine before the catalytic converter achieves the light-off temperature to hasten light-off of the catalytic converter.
Abstract: Methods and apparatus are provided for adjusting a throttle of a vehicle engine. The apparatus comprises an input sensor configured to provide an input signal having a value that approximately corresponds to an operating level of the vehicle engine requested by an operator and a memory configured to store a maximum input value for the input sensor. The maximum input value provides the value of the input signal that approximately corresponds to a maximum operating level of the vehicle engine. The apparatus is further configured to receive the input signal and access the memory to retrieve the maximum input value and further configured to update the maximum input value with the value of the input signal if the value of the input signal is greater than the maximum input value.
Type:
Grant
Filed:
July 26, 2001
Date of Patent:
December 9, 2003
Assignee:
General Motors Corporation
Inventors:
Mark Henry Costin, Paul Alan Bauerle, Robert J. Schaller, John Norman Stockbridge, Mario Vincent Maiorana, Jr., James T. Purcell, Robert Charles Simon, Jr.
Abstract: An improved control method for a dual mode compressor drive arrangement selectively operates an electric machine coupled to the compressor as a motor or a generator during operation of an engine coupled to the compressor for improved efficiency and performance. The machine is operated as a generator to increase the available power for vehicle electrical loads when compressor operation is not needed or when the engine is driving the compressor. Conversely, the machine is operated as a motor to drive the compressor under heavy engine loading or when the engine speed is outside a desired operating range defined in terms of compressor speed.
Type:
Grant
Filed:
September 7, 2001
Date of Patent:
December 9, 2003
Assignee:
General Motors Corporation
Inventors:
Gregory Alan Major, George M. Claypole, Lawrence Ziehr, Mark D. Nemesh, Michael J. Miller
Abstract: A method and apparatus for determining the mass air flow into an internal combustion engine without the use of a mass air flow sensor. Speed density and throttle position methods of estimating mass air flow are combined using a first Kalman filter. In one aspect of the invention, the input throttle position into the throttle position mass air flow estimate is the measured throttle position obtained from the throttle position sensor. In another aspect of the invention, the input throttle position into the throttle position mass air flow estimate is the output of a second Kalman filter, which uses as its inputs the measured throttle position obtained from the throttle position sensor and the desired throttle position obtained from the pedal position sensor.
Type:
Grant
Filed:
September 13, 2001
Date of Patent:
December 2, 2003
Assignee:
General Motors Corporation
Inventors:
Christian G Masson, Steven D Stiles, Vivek Mehta, Richard B Jess, Michael S Emmorey
Abstract: A vehicle steering mechanism to compensate for instabilities including a vehicle frame, a front axle coupled to the vehicle frame, the front axle further coupled to two front wheels, a rear axle coupled to the vehicle frame, the rear axle further coupled to two rear wheels, an actuator for changing the direction and angle of the two rear wheels, a trailer hitch coupled to the frame, at least one sensor for measuring instability in the trailer hitch, a controller processing the measured instability, and where the controller controls the actuator and the direction and angle of the two rear wheels to compensate for the measured instability.
Abstract: An engine control system and method smoothes torque during transitions in a displacement on demand engine. A torque loss estimator generates a torque loss signal based on torque loss due to at least one of friction, pumping and accessories. A pedal torque estimator generates a pedal torque signal. An idle torque estimator generates an idle torque signal. A summing circuit generates a difference between the pedal torque signal and the idle torque and the torque loss signals and outputs a desired brake torque signal.
Abstract: A method and apparatus for improving estimation of battery impedance when determining the state of charge of a battery including injecting a wide spectrum signal continuously across a battery when the battery is in generator mode. Additionally, the wide spectrum signal may be injected across an alternator of a conventional internal combustion engine to improve estimation of battery impedance and subsequent state of charge the battery.
Type:
Grant
Filed:
June 26, 2001
Date of Patent:
November 25, 2003
Assignee:
General Motors Corporation
Inventors:
Edward Dean Tate, Jr., Mark William Verbrugge, Shawn D. Sarbacker
Abstract: A method and apparatus to allow a vehicle controller, via a vehicle network, to automatically detect a diagnostic tool and reconfigure to communicate with the diagnostic tool.
Abstract: A method and apparatus for determining the state of charge of a lead-acid battery. The present invention includes steps to determine a current-based state of charge while accounting for such factors as current, temperature, charge efficiency, parasitic losses and self-discharge. The present invention is capable of measuring and/or calculating the open circuit voltage during and after operation to determine a voltage-based state of charge while compensating the open circuit voltage for its transient behavior and accounting for the voltage shift caused by charge events. The correlation of the open circuit voltage to the state of charge is dependent on the battery's mode of operation. The present invention is adaptive to battery aging by updating the battery resistance, correcting coulomb errors, and accounting for capacity degradation while in operation.
Abstract: A vehicle transmission system and method of controlling a vehicle transmission are provided that control clutch temperatures to extend clutch life. The system is comprised of an input drive shaft configured to be driven by an engine, an output drive shaft configured to drive a drive mechanism and a plurality of torque-transmitting devices connecting the input drive shaft to the output drive shaft and configured to engage and disengage to provide a transition between a plurality of operating ratios. The system is also comprised of a control module configured to calculate a temperature of the plurality of transmitting devices based at least in part upon a shifting status of the plurality of transmitting devices. The control module is further configured to conduct at least a first modification if the temperature is greater than a first predetermined temperature and a second modification if the temperature is greater than a second predetermined temperature.
Type:
Grant
Filed:
August 13, 2001
Date of Patent:
November 11, 2003
Assignee:
General Motors Corporation
Inventors:
Peter E. Wu, James D. Hendrickson, Joel H. Gunderson
Abstract: A controller for use in a switched reluctance (SR) motor drive is provided. The controller includes a DC—DC converter coupled to an inverter. The DC—DC converter can be a buck converter, a boost converter, or a buck-boost converter. The control parameters to the DC—DC converter can be optimal. In addition, the bus voltage of the motor drive can be reduced to a level such that the motor operates in single pulse mode. A capacitor can be connected in parallel across the outputs of the DC—DC converter supplying the inverter. Using the DC—DC converter to indirectly profile the phase current can reduce motor torque ripple.