Gm Global Technolgoy Operations, Inc.

Xuefeng Tim Tao

Steven Patrick Moorman

Tung-Ming Hsieh

Christopher Jay Weingartz

Jeryl McIver

Gregory A Hubbard

Anthony H Heap

Matthew D Whitton

Todd M Steinmetz

Jayson S Schwalm

Jonathan P Kish

David H Vu

John William Boughner

Chunhao J Lee

Farzad Samie

Jy-Jen F Sah

Paul G Otanez

William R Cawthorne

John E Marano

Xu Chen

Craig J Hawkins

Chinar S Ghike

Matthew Kempeinen

Alfonso G Hysko

Andreas Gustavsson

Scott R Verna

Fei An

Kumaraswamy V Hebbale

Hualin Tan

Ronald F Lochocki, Jr

David W Wright

Michael A Kropinski

Parsa Mahmoudieh

Thomas M Sherman

Ronald W Van Diepen

David Chris Webert

Donald D Crites

Colin Hultengren

Kenneth K Lang

Greg J Perantoni

Richard L Tiberg

Scott A Hearld

James L Lanzon

Daniel J Wickman

David William Minner

Michael Chernyak

Claes Magnus Ostberg

Daniel Deras

Tobias Berndtson

Leo P Dion

Jeffrey M DeSimone

Justin Louie

Madhura N Paranjape

Zhenhu Zhuang

Johan Larsson

Manmeet Mavi

Sriram Venkataramanan

Zachary T Schleich

Bradley J Lemmen

Nick Loedeman

A system of selecting a transmission manual mode entry gear during transient driving conditions of an automobile vehicle includes a transmission in an automobile vehicle. An engine is connected to the transmission. A torque converter is connected to the transmission, and a differential provides drive output. A controller is in communication with the engine and the transmission. A shift device is in communication with the controller allowing manual selection by an operator of the automobile vehicle between a Park, a Reverse, a Neutral, a Drive and a Low or Manual (PRNDL) operating modes. A predicted gear is frozen close to a real gear at a time of entrance into the Manual mode.

Continuously variable transmission tap gear entry ratio selection during transient driving conditions

A method and system for selecting a speed ratio for a continuously variable transmission (CVT) of a vehicle during braking. The method and system includes determining a Current Actual Speed Ratio of the CVT when the distance of a brake pedal travel exceeds a predetermined distance, determining, by a transmission control module (TCM), an amount of Available Speed Ratio Change (&#x394;r), a Current Ratio Change Capability (Current-{dot over (r)}), and a Predictive Ratio Change Capability (Predictive-{dot over (r)}). The method further includes the TCM calculating a Time to Reach the Minimum Under-drive Ratio (t), calculating a Predicted Velocity of the Vehicle (v) using (t), determining a Desired Speed Ratio of the CVT using the Predicted Velocity of the Vehicle (v), and actuating the CVT to the Desired Speed Ratio.

Ratio selection method for a continuously variable transmission during deceleration by braking

A pressure sensor rationality diagnostic for a dual clutch transmission includes a series of sensor tests. One such test includes charging an oil accumulator to a maximum pressure and storing the maximum pressure value. After performing a discharge pressure event and measuring the pressure value, the difference between the max pressure value and the discharge pressure value is calculated to determine if the difference is less than a predetermined threshold. If the difference is less than the predetermined threshold then at least one remedial action is performed which may include a driver alert or default charging mode. Additionally, similar sensor tests are performed to determine if faults exists and, if true, at least one remedial action is performed.

Pressure sensor rationality diagnostic for a dual clutch transmission

A powertrain system including an engine and transmission is described, and includes a temperature sensor disposed to monitor a hydraulic fluid for the transmission. A method for monitoring the temperature sensor includes monitoring engine operation including engine coolant temperature and monitoring a signal output from the temperature sensor. An indicated temperature slope is determined based upon the signal output from the temperature sensor, and a temperature region associated with the engine coolant temperature is determined. Performance of the temperature sensor is evaluated based upon the indicated temperature slope and minimum and maximum temperature slope thresholds that are associated with the temperature region.

Method and apparatus to monitor a temperature sensor

A method for learning the bite point of a position-controlled clutch in a vehicle having an engine and a transmission includes commanding an engagement of a clutch fork via a controller when the transmission is in park and the engine is idling. The method also includes controlling an apply position of the clutch via the controller, calculating a clutch torque capacity of the clutch, and measuring the apply position via a position sensor. The apply position is recorded as the clutch bite point when the calculated clutch torque capacity equals a calibrated clutch torque capacity. The transmission is then controlled using the recorded clutch bite point. A system includes the transmission, input clutches, and a controller configured to execute the method. A vehicle includes an engine, the transmission, the position-controlled input clutch, and the controller, as well as a clutch position sensor.

Transmission system with clutch bite point learning logic

A system according to the principles of the present disclosure includes a longitudinal acceleration estimation module, a vehicle longitudinal acceleration sensor, a road grade estimation module, and an actuator control module. The longitudinal acceleration estimation module estimates a longitudinal acceleration of a vehicle based on at least one of a transmission output speed and a wheel speed. The vehicle longitudinal acceleration sensor measures the longitudinal acceleration of the vehicle. The road grade estimation module estimates a grade of a road on which the vehicle is traveling based on the estimated longitudinal acceleration and the measured longitudinal acceleration. The actuator control module controls an actuator of the vehicle based on the estimated road grade.

System and method for estimating road grade based on an output of a longitudinal acceleration sensor in a vehicle

A method of controlling a transmission includes selecting a target speed of a second shaft, and measuring a second speed of the second shaft and an output speed of an output shaft. The method includes detecting a rolling neutral condition wherein a first and second clutch are uncoupled from a torque generator and a synchronizer is mated to a predicted gear to apply a load in a direction, and one of a first condition wherein the output speed is decreasing and the target speed is less than the second speed and a second condition wherein the output speed is increasing and the target speed is less than the second speed. The method then includes translating the synchronizer away from the predicted gear, coupling and decoupling the second clutch to and from the torque generator, and mating the synchronizer to the predicted gear to again apply the load in the direction.

Method of controlling a transmission

A method of learning a kiss point of a first clutch of a dual clutch transmission includes controlling a rotational speed of the input shaft to be within a pre-determined range. When both the first clutch and the second clutch are determined to be disengaged from the input shaft, and the rotational speed of the input shaft is within the pre-determined range, then the first clutch is moved from a disengaged position into an engaged position. An increase in a rotational speed of a first transmission shaft, which is coupled to the first clutch, is detected. When the increase in the rotational speed of the first transmission shaft is detected, a position of the first clutch is identified. The identified position of the first clutch is saved in a memory of a transmission control module as a learned first clutch kiss point.

Method of learning a clutch kiss point for a clutch of a dual clutch transmission

A method of identifying a synchronous position of a synchronizer actuator fork includes sensing a deceleration rate of a first shaft, when a synchronizer is positioned in a neutral position, to define a first rate of deceleration. The synchronizer is moved along the first shaft from the neutral position toward a gear with a synchronizer actuator fork. A deceleration rate of the first shaft is sensed, while the synchronizer actuator fork moves the synchronizer along the first shaft, to identify a change from the first rate of deceleration to a second rate of deceleration. The location, of the synchronizer actuator fork relative to the first shaft, at which the rate of acceleration of the first shaft changes from the first rate of deceleration to the second rate of deceleration, is identified as the synchronous position of the synchronizer actuator fork.

Method of identifying a synchronous position of a synchronizer actuator fork of a dual clutch transmission

A system for a vehicle includes a speed determination module, a buffer module, and a speed prediction module. The speed determination module determines changes in measured vehicle speed. The buffer module stores the determined changes in measured vehicle speed. The speed prediction module predicts a speed of the vehicle when the measured vehicle speed is less than a predetermined threshold, wherein the predicted vehicle speed is based on an average of the stored changes in measured vehicle speed.

System and method for determining vehicle speed

A method of controlling thermal loading in a multi-speed dual-clutch transmission (DCT) that is paired with an internal combustion engine in a vehicle is provided. The method includes detecting operation of the vehicle and ascertaining a degree of thermal loading on the DCT. The method also includes selecting a remedial action corresponding to the ascertained degree of thermal loading. Additionally, the method includes activating the selected remedial action such that the thermal loading on the DCT is reduced. A vehicle having a DCT, an internal combustion engine, and a controller configured to control thermal loading in the DCT is also disclosed.

Dual-clutch transmission thermal management

A method of cooling a multi-speed dual-clutch transmission (DCT) that is paired with an internal combustion engine in a vehicle includes detecting operation of the vehicle. The method also includes sensing an increase in temperature of a subsystem of the DCT while the vehicle is operating. The method also includes selecting a remedial action in response to the sensed temperature. The method aditionally includes activating the selected remedial action such that the temperature of the subsystem is reduced.

A method of controlling a dual clutch transmission includes repeatedly moving a synchronizer into interlocking engagement with a first gear with an actuator fork, and repeatedly sensing a position of the actuator fork for each occurrence that the actuator fork moves the synchronizer into the interlocking engagement with the first gear. The sensed positions of the actuator fork are averaged to define a first engaged position of the actuator fork for engaging the first gear. A second engaged position at which the actuator fork couples the synchronizer to a second gear may be determined in the same manner. A neutral position may be determined by identifying the axial locations of peak acceleration of the actuator fork while moving between the first engaged position and the second engaged position. The identified axial locations are averaged to define the neutral position of the actuator fork.

Method of learning engaged positions and a neutral position of a synchronizer actuator fork of a dual clutch transmission

A vehicle simulation system includes a first simulation model that when executed simulates a software ring along with other software of a vehicle module. The vehicle simulation system further includes a second simulation model of the software ring. A bypass switch that has a first state and a second state. A bypass switching module switches the bypass switch between the first simulation model and the second simulation model based on a bypass signal and a ring enabling signal. A simulation control module executes code of a vehicle simulation model including software in-the-loop (SIL) testing of a selected one of the first simulation model and the second simulation model based on state of the bypass switch.

Vehicle simulation system with software-in-the-loop bypass control

A method for controlling actuation of a torque converter clutch includes monitoring a transmission input speed, comparing the monitored transmission input speed to a threshold input speed, and, when the transmission input speed is less than the threshold input speed, controlling an engine speed based upon a desired minimum engine speed. Controlling the engine speed based upon the desired minimum engine speed includes monitoring a minimum engine speed critical parameter, determining the desired minimum engine speed based upon the minimum engine speed critical parameter, comparing the engine speed to the desired minimum engine speed, and controlling actuation of the clutch device based upon a result of the comparing the engine speed to the desired minimum engine speed.

Engine speed assist torque converter clutch control

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Northville, MI, United States of America

Xuefeng Tim Tao