Patent application number | Description | Published |
20120065838 | SPEED CONSTRAINT CONTROL PROCEDURE - A method includes receiving speed constraints associated with two independent vehicle components and receiving speed constraints associated with a first dependent vehicle component and a second dependent vehicle component. The method further includes defining a relationship between the received speed constraints of the independent vehicle components and the first and second dependent vehicle components. Moreover, speed values of an unknown speed constraint associated with a third dependent component are derived based on the defined relationship between the received speed constraints of the independent vehicle components and the first and second dependent vehicle components. | 03-15-2012 |
20120089281 | METHOD AND DRIVELINE STABILITY CONTROL SYSTEM FOR A VEHICLE - A method for controlling driveline stability in a vehicle includes generating an activation signal indicative of a predetermined vehicle maneuver, which may include a hard braking maneuver on a low coefficient of friction surface. A quick automatic shift to a neutral gear state is executed with a rapid dumping or bleeding off of clutch pressure in a designated output clutch of the vehicle. An activated state of an antilock braking system (ABS) may be used as part of the activation signal. The shift to the neutral gear state may occur only when a current transmission operating state is associated with the high level of driveline inertia. A vehicle includes a transmission and a control system configured to execute the above method. | 04-12-2012 |
20120089282 | METHOD AND ENGINE STABILITY CONTROL SYSTEM FOR A HYBRID ELECTRIC VEHICLE - A method for controlling a hybrid electric vehicle having a control system, a traction motor, and an engine includes generating an activation signal during a predetermined vehicle maneuver. The predetermined vehicle maneuver is a threshold hard braking maneuver on a surface having a low coefficient of friction. The method also includes processing the activation signal using the control system, and using the traction motor to command an injection or a passing of a feed-forward torque to the driveline of the vehicle. The feed-forward torque is in the same direction as the engine torque, and prevents a drive shaft of the engine from spinning in reverse during the maneuver. The method may include generating the activation signal in response to detecting an active state of the ABS controller. A hybrid electric vehicle includes an engine, a traction motor, and a control system configured to execute the above method. | 04-12-2012 |
20120158224 | METHOD AND APPARATUS TO PROTECT POWERTRAIN COMPONENTS FROM EXCESSIVE FORCE DAMAGE DUE TO WHEEL LOCKUP - An example vehicle includes an engine and a motor-generator configured to generate a torque in a first direction. A torque limiter clutch is configured to dissipate a torque in a second direction that opposes the first torque. The torque in the second direction may be caused by a force event. A control processor is configured to detect a possible force event and control the torque limiter clutch in response to detecting the possible force event. A method of controlling the torque limiter clutch includes detecting a possible force event, reducing fluid pressure to the torque limiter clutch in response to detecting the possible force event, confirming the possible force event, maintaining the reduced fluid pressure to the torque limiter clutch if the force event is confirmed, and increasing the fluid pressure to the torque limiter clutch if the force event is not confirmed. | 06-21-2012 |
20120303191 | Method of Prioritizing Output Torque And Off-Going Clutch Torque Constraints During A Torque Phase - A system for a vehicle includes a constraint module that generates a plurality of constraints. An output torque module generates a commanded output torque based on a torque request and the plurality of constraints. A split torque module determines a first torque and a second torque to be applied to a transmission of the vehicle based on the plurality of constraints and the commanded output torque. A first one of the plurality of constraints corresponding to a first clutch is adjusted from a first range of values to a second range of values that is different from the first range of values in response to a command to offload the first clutch. | 11-29-2012 |
20130053212 | CONTROL SYSTEM FOR A HYBRID POWERTRAIN SYSTEM - A vehicle includes a powertrain with an engine, first and second torque machines, and a hybrid transmission. A method for operating the vehicle includes operating the engine in an unfueled state, releasing an off-going clutch which when engaged effects operation of the hybrid transmission in a first continuously variable mode, and applying a friction braking torque to a wheel of the vehicle to compensate for an increase in an output torque of the hybrid transmission resulting from releasing the off-going clutch. Subsequent to releasing the off-going clutch, an oncoming clutch which when engaged effects operation of the hybrid transmission in a second continuously variable mode is synchronized. Subsequent to synchronization of the oncoming clutch, the oncoming clutch is engaged. | 02-28-2013 |
20130217536 | METHOD AND APPARATUS FOR EXECUTING AN ASYNCHRONOUS CLUTCH-TO-CLUTCH SHIFT IN A HYBRID TRANSMISSION - A hybrid transmission includes first and second electric machines. A method for operating the hybrid transmission in response to a command to execute a shift from an initial continuously variable mode to a target continuously variable mode includes increasing torque of an oncoming clutch associated with operating in the target continuously variable mode and correspondingly decreasing a torque of an off-going clutch associated with operating in the initial continuously variable mode. Upon deactivation of the off-going clutch, torque outputs of the first and second electric machines and the torque of the oncoming clutch are controlled to synchronize the oncoming clutch. Upon synchronization of the oncoming clutch, the torque for the oncoming clutch is increased and the transmission is operated in the target continuously variable mode. | 08-22-2013 |
20130225361 | METHOD AND APPARATUS FOR EXECUTING A SHIFT IN A HYBRID TRANSMISSION - A method for executing a transmission shift in a hybrid transmission including first and second electric machines includes executing a shift-through-neutral sequence from an initial transmission state to a target transmission state including executing an intermediate shift to neutral. Upon detecting a change in an output torque request while executing the shift-through-neutral sequence, possible recovery shift paths are identified. Available ones of the possible recovery shift paths are identified and a shift cost for each said available recovery shift path is evaluated. The available recovery shift path having a minimum shift cost is selected as a preferred recovery shift path and is executed to achieve a non-neutral transmission state. | 08-29-2013 |
20130296135 | METHOD AND APPARATUS FOR EXECUTING A SHIFT PATH TO A TARGET POWERSTRAIN STATE - A method for controlling a transmission of a powertrain system includes executing a single source shortest path search to identify a preferred shift path originating with an initial powertrain state and terminating at a target powertrain state, wherein the single source shortest path search employs transition-specific costs and situational costs to identify the preferred shift path. The preferred shift path is executed to achieve the target powertrain state. | 11-07-2013 |
20140045654 | CONTROL OF CLUTCH FILL COMMAND BASED ON HYDRAULIC STATE OF ONCOMING CLUTCH - A system and method of controlling a clutch fill command based on the hydraulic state of an oncoming clutch is provided. A vehicle includes a hydraulically-actuated oncoming clutch that is configured to engage during a shift event from one operating mode of the vehicle to another. A controller is configured to generate a clutch fill command at an initial time such that completion of the clutch fill command is synchronized with an identified speed profile of the oncoming clutch. The oncoming clutch defines a real-time hydraulic state when the clutch fill command is generated. The controller is configured to generate a real-time acceptable speed margin for the oncoming clutch based at least partially on the real-time hydraulic state of the oncoming clutch. The controller is configured to cancel the clutch fill command if a real-time speed of the oncoming clutch is outside the generated real-time acceptable speed margin. | 02-13-2014 |
20140081491 | ACCELERATION PROFILE-BASED CONTROL OF AN OFFGOING CLUTCH OPERATION - A vehicle includes a torque generating device, a transmission, and a controller. The transmission has one or more clutches. The controller executes a method, which includes measuring an amount of slip across an identified offgoing clutches and determining whether the offgoing clutches have slipped prior to a modeled clutch torque capacity reaching zero. A status is assigned indicating that the offgoing clutches are released if the offgoing clutch has slipped prior to the modeled clutch capacity reaching zero. The controller induces slip across the identified offgoing clutches to a calibrated low, non-zero level after recording the value, including by enforcing the low, non-zero slip value using one or more acceleration profiles. | 03-20-2014 |