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: 20170345113
    Abstract: A system and method of communicating vehicle-based service offers between wireless devices includes: receiving, at a central facility, a location from a wireless device used by a potential service consumer; determining, at the central facility, a community from the received location, wherein the community represents a geofenced boundary the location exists within; associating the wireless device with the community in a database at the central facility; receiving at the central facility a service offer and a location or community from a second wireless device used by a vehicle owner; searching the database for the community associated with the second wireless device; determining that the community associated with the second wireless device is also associated with the wireless device in the database; and transmitting the service offer received from the second wireless device to the wireless device.
    Type: Application
    Filed: May 24, 2016
    Publication date: November 30, 2017
    Inventor: Krishnendu KAR
  • Patent number: 9670857
    Abstract: A method of controlling torque output of a power-plant during launch of a vehicle having a transmission with a manually-operated clutch is disclosed. The power-plant torque is varied based on clutch pedal and throttle pedal positions using a proportional-integral-derivative (PID) control logic in an electronic fuel control system. The method includes setting power-plant idle speed, detecting clutch engagement without application of the throttle pedal, and raising power-plant torque after clutch engagement is detected. In each PID feedback loop, the method includes detecting actual power-plant speed and a rate of change in actual power-plant speed, and adjusting the raised power-plant torque in response to the determined rate of change in actual power-plant speed.
    Type: Grant
    Filed: August 17, 2015
    Date of Patent: June 6, 2017
    Assignee: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Leon Cribbins, Thomas Weglarz
  • Publication number: 20170051695
    Abstract: A method of controlling torque output of a power-plant during launch of a vehicle having a transmission with a manually-operated clutch is disclosed. The power-plant torque is varied based on clutch pedal and throttle pedal positions using a proportional-integral-derivative (PID) control logic in an electronic fuel control system. The method includes setting power-plant idle speed, detecting clutch engagement without application of the throttle pedal, and raising power-plant torque after clutch engagement is detected. In each PID feedback loop, the method includes detecting actual power-plant speed and a rate of change in actual power-plant speed, and adjusting the raised power-plant torque in response to the determined rate of change in actual power-plant speed.
    Type: Application
    Filed: August 17, 2015
    Publication date: February 23, 2017
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Krishnendu Kar, Leon Cribbins, Thomas Weglarz
  • Patent number: 9309824
    Abstract: A driver request module determines a driver torque request based on an accelerator pedal position, a first difference between a target engine speed and a transmission input speed, and a second difference between the transmission input speed and a measured engine speed. A request generating module generates first and second torque requests based on the driver torque request. An engine speed control module generates third and fourth torque requests based on a target engine speed and the first and second differences. Based on a mode signal: a first selection module sets a fifth torque request to one of the first and third torque requests; and a second selection module sets a sixth torque request to one of the second and fourth torque requests. An adjusting module selectively adjusts an engine operating parameter based on at least one of the fifth and sixth torque requests.
    Type: Grant
    Filed: December 17, 2012
    Date of Patent: April 12, 2016
    Assignee: GM Global Technology Operations LLC
    Inventor: Krishnendu Kar
  • Patent number: 9284902
    Abstract: A difference module determines a difference between an engine speed and a transmission input shaft speed. A state control module sets a signal to a first state when a driver releases an accelerator pedal and selectively transitions the signal from the first state to a second state when the difference is less than zero. An immediate torque request module decreases an engine torque request when the signal is in the first state and selectively increases the engine torque request when the signal is in the second state. At least one of: a spark control module that selectively adjusts spark timing based on the engine torque request; and a fuel control module that selectively adjusts fueling based on the engine torque request.
    Type: Grant
    Filed: August 16, 2013
    Date of Patent: March 15, 2016
    Assignee: GM Global Technology Operations LLC
    Inventors: Bret J. Keller, Krishnendu Kar
  • Patent number: 9127603
    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: Grant
    Filed: January 26, 2012
    Date of Patent: September 8, 2015
    Inventors: Ronald W. Knoebel, Krishnendu Kar, Ryan Goode
  • Patent number: 9091219
    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: Grant
    Filed: March 1, 2011
    Date of Patent: July 28, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Pahngroc Oh, Andrew W. Baur
  • Patent number: 9090244
    Abstract: A method of maintaining a substantially stable engine speed after a garage shift of an automatic transmission includes identifying a moment when a load from the automatic transmission is applied to an engine via a torque converter during the garage shift based on a first turbine speed change with respect to a reference engine speed change and a second turbine speed change with respect to an actual engine speed change. The method further includes generating a feed forward torque command based on a turbine speed decrement after identifying the moment when the load from the automatic transmission is applied to the engine, and controlling the engine based on the feed forward torque command to maintain a substantially stable engine speed after the garage shift.
    Type: Grant
    Filed: March 8, 2013
    Date of Patent: July 28, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Junhong Dai, Wenbo Wang, Krishnendu Kar, Leon Cribbins
  • Patent number: 9080515
    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: Grant
    Filed: September 6, 2012
    Date of Patent: July 14, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Bret J. Keller
  • Patent number: 9074537
    Abstract: An adaptive engine speed control system includes an idle condition module that determines whether the engine is idling and determines whether an actual engine speed is different than a desired engine speed. The desired engine speed corresponds to a commanded engine speed. A torque reserve determination module adjusts at least one of a torque reserve and the desired engine speed based on the determination of whether the engine is idling and the determination that the actual engine speed differs from the desired engine speed. The torque reserve corresponds to a quantity of torque reserved to respond to an anticipated future load on the engine.
    Type: Grant
    Filed: November 9, 2012
    Date of Patent: July 7, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Wenbo Wang, Thomas C. Pelton, Alfred E. Spitza, Jr., Timothy J. Braman, Matthew M. Manning, Krishnendu Kar
  • Patent number: 9056603
    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: Grant
    Filed: January 28, 2013
    Date of Patent: June 16, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Krishnendu Kar, Leon Cribbins, William R. Mayhew, Timothy J. Keenan
  • Patent number: 9056604
    Abstract: A vehicle includes an engine, transmission, engine control module (ECM), and transmission control module (TCM). The transmission includes an input member and an input clutch which selectively connects a crankshaft of the engine to the input member. The TCM identifies a target clutch torque of the input clutch during a creep maneuver of the vehicle, and communicates the identified target clutch torque to the ECM. The ECM maintains engine idle speed at a threshold level through the creep maneuver and a requested launch using the target clutch torque as a feed-forward term. A method includes identifying a target clutch torque of the input clutch during a creep maneuver, and communicating the identified target clutch torque to the ECM. The idle speed is maintained at a threshold level by the ECM through the creep maneuver and a detected launch using the target clutch torque as a feed-forward idle speed control term.
    Type: Grant
    Filed: July 26, 2013
    Date of Patent: June 16, 2015
    Assignee: GM Global Technology Operations LLC
    Inventors: Ronald F. Lochocki, Jr., Krishnendu Kar, Colin Hultengren, Leon Cribbins
  • Publication number: 20150051808
    Abstract: A difference module determines a difference between an engine speed and a transmission input shaft speed. A state control module sets a signal to a first state when a driver releases an accelerator pedal and selectively transitions the signal from the first state to a second state when the difference is less than zero. An immediate torque request module decreases an engine torque request when the signal is in the first state and selectively increases the engine torque request when the signal is in the second state. At least one of: a spark control module that selectively adjusts spark timing based on the engine torque request; and a fuel control module that selectively adjusts fueling based on the engine torque request.
    Type: Application
    Filed: August 16, 2013
    Publication date: February 19, 2015
    Applicant: GM Global Technology Operations LLC
    Inventors: Bret J. Keller, Krishnendu Kar
  • Publication number: 20150032345
    Abstract: A vehicle includes an engine, transmission, engine control module (ECM), and transmission control module (TCM). The transmission includes an input member and an input clutch which selectively connects a crankshaft of the engine to the input member. The TCM identifies a target clutch torque of the input clutch during a creep maneuver of the vehicle, and communicates the identified target clutch torque to the ECM. The ECM maintains engine idle speed at a threshold level through the creep maneuver and a requested launch using the target clutch torque as a feed-forward term. A method includes identifying a target clutch torque of the input clutch during a creep maneuver, and communicating the identified target clutch torque to the ECM. The idle speed is maintained at a threshold level by the ECM through the creep maneuver and a detected launch using the target clutch torque as a feed-forward idle speed control term.
    Type: Application
    Filed: July 26, 2013
    Publication date: January 29, 2015
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Ronald F. Lochocki, JR., Krishnendu Kar, Colin Hultengren, Leon Cribbins
  • Patent number: 8919323
    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: Grant
    Filed: March 27, 2012
    Date of Patent: December 30, 2014
    Inventors: Krishnendu Kar, Leon Cribbins
  • Publication number: 20140257651
    Abstract: A method of maintaining a substantially stable engine speed after a garage shift of an automatic transmission includes identifying a moment when a load from the automatic transmission is applied to an engine via a torque converter during the garage shift based on a first turbine speed change with respect to a reference engine speed change and a second turbine speed change with respect to an actual engine speed change. The method further includes generating a feed forward torque command based on a turbine speed decrement after identifying the moment when the load from the automatic transmission is applied to the engine, and controlling the engine based on the feed forward torque command to maintain a substantially stable engine speed after the garage shift.
    Type: Application
    Filed: March 8, 2013
    Publication date: September 11, 2014
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Junhong Dai, Wenbo Wang, Krishnendu Kar, Leon Cribbins
  • Patent number: 8744716
    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: Grant
    Filed: March 29, 2010
    Date of Patent: June 3, 2014
    Inventors: Krishnendu Kar, Michael Livshiz, Christopher E. Whitney, Cheryl A. Williams, Etsuko Muraji Stewart, Matthew M. Manning
  • Publication number: 20140136074
    Abstract: An adaptive engine speed control system includes an idle condition module that determines whether the engine is idling and determines whether an actual engine speed is different than a desired engine speed. The desired engine speed corresponds to a commanded engine speed. A torque reserve determination module adjusts at least one of a torque reserve and the desired engine speed based on the determination of whether the engine is idling and the determination that the actual engine speed differs from the desired engine speed. The torque reserve corresponds to a quantity of torque reserved to respond to an anticipated future load on the engine.
    Type: Application
    Filed: November 9, 2012
    Publication date: May 15, 2014
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Wenbo Wang, Thomas C. Pelton, Alfred E. Spitza, JR., Timothy J. Braman, Matthew M. Manning, Krishnendu Kar
  • Publication number: 20140081559
    Abstract: A driver request module determines a driver torque request based on an accelerator pedal position, a first difference between a target engine speed and a transmission input speed, and a second difference between the transmission input speed and a measured engine speed. A request generating module generates first and second torque requests based on the driver torque request. An engine speed control module generates third and fourth torque requests based on a target engine speed and the first and second differences. Based on a mode signal: a first selection module sets a fifth torque request to one of the first and third torque requests; and a second selection module sets a sixth torque request to one of the second and fourth torque requests. An adjusting module selectively adjusts an engine operating parameter based on at least one of the fifth and sixth torque requests.
    Type: Application
    Filed: December 17, 2012
    Publication date: March 20, 2014
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventor: Krishnendu Kar
  • Patent number: 8657721
    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: Grant
    Filed: May 5, 2011
    Date of Patent: February 25, 2014
    Inventors: Christopher E. Whitney, Jeremy V. Horgan, Scott A. Hearld, Lars Mikael Buur, Ryan Goode, Krishnendu Kar