Patents by Inventor Krishnendu Kar

Krishnendu Kar has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20130325291
    Abstract: A system according the principles of the present disclosure includes a torque determination module and a torque limit module. The torque determination module determines a first torque that prevents an engine from stalling. The torque limit module limits engine torque based on the first torque when a driver actuates an accelerator pedal from a first position in which the accelerator pedal is not depressed to a second position in which the accelerator pedal is depressed.
    Type: Application
    Filed: September 6, 2012
    Publication date: December 5, 2013
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Krishnendu Kar, Bret J. Keller
  • Publication number: 20130311055
    Abstract: A method of controlling the performance of a vehicle from a stationary condition includes operating a vehicle powertrain in a creep mode following the disengagement of a driver-operated braking device; and operating the vehicle powertrain in a launch mode following an engagement of a driver-operated acceleration device subsequent to the disengagement of the driver-operated braking device. Operating a vehicle powertrain in a creep mode includes: applying a friction clutch to couple an engine crankshaft of the vehicle powertrain with an input shaft of the transmission; determining a torque command to accelerate the vehicle powertrain at a predetermined rate; providing the torque command to an engine controller to controllably increase the input torque to the transmission; and operating a closed loop engine speed control module to prevent the crankshaft speed from slowing below a predetermined engine idle speed.
    Type: Application
    Filed: February 14, 2013
    Publication date: November 21, 2013
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Christopher E. Whitney, Klaus Pochner, Colin Hultengren, Krishnendu Kar
  • Publication number: 20130297160
    Abstract: A system according to the principles of the present disclosure includes a downshift determination module and a speed control module. The downshift determination module determines when a closed-throttle downshift occurs. The closed-throttle downshift is a downshift of a transmission when a throttle valve of an engine is closed. The speed control module controls engine speed based on turbine speed during the closed-throttle downshift. The turbine speed is a speed of a turbine in a torque converter that couples the engine to the transmission.
    Type: Application
    Filed: January 28, 2013
    Publication date: November 7, 2013
    Applicant: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Leon Cribbins, William R. Mayhew, Timothy J. Keenan
  • Publication number: 20130255625
    Abstract: A system according to the principles of the present disclosure includes a gain determination module, a desired torque determination module, and an engine operation control module. The gain determination module determines a gain based on a desired speed of an engine and a change rate of an actual speed of the engine. The desired torque determination module determines a desired torque based on the gain and a difference between the actual speed and the desired speed. The engine operation control module controls at least one of a throttle area, a spark timing, and a fueling rate based on the desired torque.
    Type: Application
    Filed: March 27, 2012
    Publication date: October 3, 2013
    Applicant: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Leon Cribbins
  • Publication number: 20130196819
    Abstract: A method of controlling a vehicle includes identifying an operating state of a torque converter clutch to be one of a locked operating state, or an unlocked operating state. A rotational speed of a turbine of a torque converter is sensed. When the torque converter clutch is operating in the locked operating state, a desired engine speed is defined to equal the sensed rotational speed of the turbine less a first slip value. When the torque converter clutch is operating in the unlocked operating state, the desired engine speed is defined to equal the sensed rotational speed of the turbine less a second slip value. At least one operating parameter of the engine is adjusted to control a torque output of the engine to affect a rotational speed of the engine so that the rotational speed of the engine is equal to the defined desired engine speed.
    Type: Application
    Filed: January 30, 2012
    Publication date: August 1, 2013
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Krishnendu Kar, Kristian Keary
  • Publication number: 20130080031
    Abstract: A system for a vehicle includes a rate of change module, a period estimation module, a deceleration fuel cutoff (DFCO) module, and an injection control module. The rate of change module determines a rate of change of an engine speed. While an engine is being fueled, the period estimation module determines an estimated period of a next DFCO event based on the rate of change of the engine speed. The DFCO control module selectively generates a DFCO signal based on the estimated period. The injection control module cuts off fuel to the engine when the DFCO signal is generated.
    Type: Application
    Filed: January 26, 2012
    Publication date: March 28, 2013
    Applicant: GM Global Technology Operations LLC
    Inventors: Ronald W. Knoebel, Krishnendu Kar, Ryan Goode
  • Patent number: 8386150
    Abstract: An engine control system includes a fuel cutoff (FCO) module, a fuel control module, and a spark control module. The FCO module, when a FCO event is disabled, determines a feed-forward (FF) number of cylinders to offset a delay period associated with supplying fuel to the cylinders of an engine and selectively maintains a FCO torque request at a predetermined torque. The fuel control module commands fuel be supplied to the FF number of cylinders of the engine when the FCO event is disabled. The spark control module maintains a spark timing of the FF number of cylinders at a fully retarded spark timing based on the FCO torque request.
    Type: Grant
    Filed: April 28, 2010
    Date of Patent: February 26, 2013
    Assignee: GM Global Technology Operations LLC
    Inventors: Christopher E. Whitney, Jun Lu, Michael J. Pitsch, Ryan Goode, Krishnendu Kar
  • Patent number: 8364381
    Abstract: A control system for an engine includes a speed error determination module that periodically determines an engine speed error rate based on a difference between a measured speed and a desired speed of the engine, and a torque reserve module that monitors the engine speed error rate and that selectively adjusts a torque reserve of the engine based on the engine speed error rate. The torque reserve module maintains the torque reserve at a predetermined first torque reserve amount while the engine speed error rate is less than a predetermined first error rate and selectively increases the torque reserve above the first torque reserve amount when the engine speed error rate increases above a predetermined second error rate greater than the first error rate. The torque reserve module decreases the torque reserve when the engine speed error rate decreases below the first error rate. A related method is also provided.
    Type: Grant
    Filed: August 21, 2009
    Date of Patent: January 29, 2013
    Inventors: Krishnendu Kar, Daniel Lee Baibak
  • Patent number: 8306722
    Abstract: A control system includes an engine speed control module, a fuel control module, and an air control module. The engine speed control module controls an actual speed of an engine based a desired power to be generated by combustion in the engine, wherein the desired power is a product of a desired speed of the engine and a desired torque output of the engine. When operating in a fuel lead mode, the fuel control module controls fuel flow in the engine by adjusting a desired fuel mass for each activated cylinder of the engine based on the desired power. The air control module controls air flow in the engine based on an actual air/fuel ratio of the engine resulting from the desired fuel mass.
    Type: Grant
    Filed: February 5, 2010
    Date of Patent: November 6, 2012
    Inventors: Christopher E. Whitney, Krishnendu Kar, Massimiliano Maira, Luca Scavone, Michael Livshiz
  • Publication number: 20120234123
    Abstract: A powertrain system includes an engine control module that generates a negative torque transition signal based on a pending negative torque event of an engine. A transmission control module receives the negative torque transition signal from the engine control module. The transmission control module increases a slip speed of a torque converter clutch in preparation for the pending negative torque event by adjusting pressure in the torque converter clutch prior to the pending negative torque event. The transmission control module decreases the slip speed in the torque converter clutch based on completion of a transition at least one of to the pending negative torque event and from the pending negative torque event.
    Type: Application
    Filed: May 5, 2011
    Publication date: September 20, 2012
    Applicant: GM Global Technology Operations LLC
    Inventors: Christopher E. Whitney, Jeremy V. Horgan, Scott A. Hearld, Lars Mikael Buur, Ryan Goode, Krishnendu Kar
  • Publication number: 20120150399
    Abstract: A control system includes a driver torque determination module, a lash zone torque determination module, a rate limit determination module, and an immediate torque determination module. The driver torque determination module determines a driver torque request when a driver depresses an accelerator pedal while a vehicle is coasting. The lash zone torque determination module determines a lash zone torque based on a transmission gear and an engine speed. The rate limit determination module determines an adjustment rate limit based on a previous immediate torque request, the lash zone torque, and the transmission gear. The immediate torque determination module determines a present immediate torque request based on the driver torque request and selectively determines the present immediate torque request based on the adjustment rate limit.
    Type: Application
    Filed: March 1, 2011
    Publication date: June 14, 2012
    Applicant: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Pahngroc Oh, Andrew W. Baur
  • Publication number: 20110270509
    Abstract: An engine control system includes a fuel cutoff (FCO) module, a fuel control module, and a spark control module. The FCO module, when a FCO event is disabled, determines a feed-forward (FF) number of cylinders to offset a delay period associated with supplying fuel to the cylinders of an engine and selectively maintains a FCO torque request at a predetermined torque. The fuel control module commands fuel be supplied to the FF number of cylinders of the engine when the FCO event is disabled. The spark control module maintains a spark timing of the FF number of cylinders at a fully retarded spark timing based on the FCO torque request.
    Type: Application
    Filed: April 28, 2010
    Publication date: November 3, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Christopher E. Whitney, Jun Lu, Michael J. Pitsch, Ryan Goode, Krishnendu Kar
  • Publication number: 20110195817
    Abstract: A control system includes an engine speed control module, a fuel control module, and an air control module. The engine speed control module controls an actual speed of an engine based a desired power to be generated by combustion in the engine, wherein the desired power is a product of a desired speed of the engine and a desired torque output of the engine. When operating in a fuel lead mode, the fuel control module controls fuel flow in the engine by adjusting a desired fuel mass for each activated cylinder of the engine based on the desired power. The air control module controls air flow in the engine based on an actual air/fuel ratio of the engine resulting from the desired fuel mass.
    Type: Application
    Filed: February 5, 2010
    Publication date: August 11, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Christopher E. Whitney, Krishnendu Kar, Massimiliano Maira, Luca Scavone, Michael Livshiz
  • Publication number: 20110139117
    Abstract: An engine control system includes a mode selection module that is configured to select an operating mode from one of an open loop control mode, a torque control mode, and a speed control mode based on an engine speed and a driver input. An axle torque arbitration (ABA) module generates ABA predicted and immediate torque requests based on the driver input. A speed control (SC) module generates a first set of SC predicted and immediate torque requests based on engine speed. A propulsion torque arbitration (PTA) module generates PTA predicted and immediate torque requests based on one of the ABA predicted and immediate torque requests and the first set of SC predicted and immediate torque requests based on the operating mode. A torque output control module controls output torque of an engine based on the PTA predicted and immediate torque requests.
    Type: Application
    Filed: March 29, 2010
    Publication date: June 16, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Krishnendu Kar, Michael Livshiz, Christopher E. Whitney, Cheryl A. Williams, Etsuko Muraji Stewart, Matthew M. Manning
  • Publication number: 20110041802
    Abstract: A control system for an engine includes a speed error determination module that periodically determines an engine speed error rate based on a difference between a measured speed and a desired speed of the engine, and a torque reserve module that monitors the engine speed error rate and that selectively adjusts a torque reserve of the engine based on the engine speed error rate. The torque reserve module maintains the torque reserve at a predetermined first torque reserve amount while the engine speed error rate is less than a predetermined first error rate and selectively increases the torque reserve above the first torque reserve amount when the engine speed error rate increases above a predetermined second error rate greater than the first error rate. The torque reserve module decreases the torque reserve when the engine speed error rate decreases below the first error rate. A related method is also provided.
    Type: Application
    Filed: August 21, 2009
    Publication date: February 24, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Krishnendu Kar, Daniel Lee Baibak
  • Patent number: 7024301
    Abstract: A system and method for controlling fuel delivery through a fuel injection system to an internal combustion engine is described. An engine controller calculates a mass of fuel for delivery to one of the cylinders through one of the fuel injectors, based upon the operation of the internal combustion engine. Gas temperature in the intake runner of the cylinder is determined, and a compensation term is selected based upon the calculated mass of fuel and the determined gas temperature in the intake runner of the cylinder. The calculated mass of fuel is adjusted using the compensation term, and the controller controls open time of the fuel injector based upon the adjusted calculated mass of fuel.
    Type: Grant
    Filed: January 14, 2005
    Date of Patent: April 4, 2006
    Assignee: Delphi Technologies, Inc.
    Inventors: Krishnendu Kar, Andrew P. Bagnasco, Sergio Eduardo Garcia, Edward George Himes
  • Patent number: 6934643
    Abstract: An ultra accurate gas injection system with vehicle transient air simulation is provided. The device includes an input device, at least one mass flow device, an air flow device, a controller, such as a PC based controller, and an output device. The air flow device issues an air flow rate signal indicative of at least the actual air flow rate and receives an air flow control signal. The controller issues gas and air flow control signals, repeatedly reads the air flow rate signal and compares the actual air flow rate with the target air flow rate. The controller adjusts the air flow control signal such that the actual air flow rate is substantially equal to the target air flow rate. The mass flow device injects at least one gas into the air stream which is subsequently emitted into the external system to simulate exhaust gas from a vehicle.
    Type: Grant
    Filed: December 15, 2003
    Date of Patent: August 23, 2005
    Assignee: Delphi Technologies, Inc.
    Inventors: Krishnendu Kar, Robert Semidey
  • Patent number: 6874360
    Abstract: A method of determining the rubbing friction torque involves characterizing fuel cutoff engine deceleration, and calculating the rubbing friction torque for any combination of engine speed and powertrain temperature is calculated in accordance with a base point rubbing friction torque RFTbase determined at a base powertrain temperature Tbase and fuel cutoff characterization data. The calibration data characterizing fuel cutoff engine deceleration is obtained by alternately enabling and cutting off engine fuel delivery to cycle the engine speed between specified set points, and measuring and recording the engine deceleration during intervals of fuel cutoff.
    Type: Grant
    Filed: September 23, 2003
    Date of Patent: April 5, 2005
    Assignee: Delphi Technologies, Inc.
    Inventors: Krishnendu Kar, Sergio Eduardo Garcia
  • Publication number: 20050061066
    Abstract: A method of determining the rubbing friction torque involves characterizing fuel cutoff engine deceleration, and calculating the rubbing friction torque for any combination of engine speed and powertrain temperature is calculated in accordance with a base point rubbing friction torque RFTbase determined at a base powertrain temperature Tbase and fuel cutoff characterization data. The calibration data characterizing fuel cutoff engine deceleration is obtained by alternately enabling and cutting off engine fuel delivery to cycle the engine speed between specified set points, and measuring and recording the engine deceleration during intervals of fuel cutoff.
    Type: Application
    Filed: September 23, 2003
    Publication date: March 24, 2005
    Inventors: Krishnendu Kar, Sergio Garcia
  • Publication number: 20040260483
    Abstract: An ultra accurate gas injection system with vehicle transient air simulation is provided. The device includes an input device, at least one mass flow device, an air flow device, a controller, such as a PC based controller, and an output device. The air flow device issues an air flow rate signal indicative of at least the actual air flow rate and receives an air flow control signal. The controller issues gas and air flow control signals, repeatedly reads the air flow rate signal and compares the actual air flow rate with the target air flow rate. The controller adjusts the air flow control signal such that the actual air flow rate is substantially equal to the target air flow rate. The mass flow device injects at least one gas into the air stream which is subsequently emitted into the external system to simulate exhaust gas from a vehicle.
    Type: Application
    Filed: December 15, 2003
    Publication date: December 23, 2004
    Inventors: Krishnendu Kar, Robert Semidey