Abstract: A powertrain including an engine and torque machines is configured to transfer torque through a multi-mode transmission to an output member. A method for controlling the powertrain includes employing a closed-loop speed control system to control torque commands for the torque machines in response to a desired input speed. Upon approaching a power limit of a power storage device transferring power to the torque machines, power limited torque commands are determined for the torque machines in response to the power limit and the closed-loop speed control system is employed to determine an engine torque command in response to the desired input speed and the power limited torque commands for the torque machines.

Abstract: A powertrain includes a controller and gear sets, clutches, rotatable members, and torque actuators, e.g., an engine and one or more motor/generator units. Each torque actuator outputs a total control torque. The total control torque from a given actuator is used to achieve a target value, which is a torque value of a member of one of the gear sets, clutches, or rotatable members. The controller includes proportional-integral (PI) control logic. The total control torque is the sum of proportional and integral torque terms from the PI control logic. The controller detects a predetermined vehicle event, for instance a change in a hybrid range state or a control gain reduction event, and then automatically resets the integral control torque term(s) for the physical target value during the requested vehicle event to thereby maintain the total control torque for the same target value through the execution of the predetermined vehicle event.

Abstract: A powertrain system including a multi-mode transmission is configured to transfer torque among an input member, torque machines and an output member. A method for controlling the multi-mode transmission includes employing a closed-loop speed control system to determine torque commands for physical torque actuators including the torque machines. The closed-loop speed control system includes employing a virtual torque actuator control scheme to generate torque commands for the physical torque actuators responsive to output commands for a plurality of virtual torque actuators.

Abstract: A method for controlling a multi-mode transmission system employing torque machines under dynamic operating conditions includes calculating a phase shift between a control parameter of one of the torque machines and a response parameter of the multi-mode transmission system under dynamic operating conditions, comparing the calculated phase shift and an expected phase shift, and executing remedial action when the calculated phase shift exceeds a threshold associated with the expected phase shift.

Abstract: A powertrain includes a controller and gear sets, clutches, rotatable members, and torque actuators, e.g., an engine and one or more motor/generator units. Each torque actuator outputs a total control torque. The total control torque from a given actuator is used to achieve a target value, which is a torque value of a member of one of the gear sets, clutches, or rotatable members. The controller includes proportional-integral (PI) control logic. The total control torque is the sum of proportional and integral torque terms from the PI control logic. The controller detects a predetermined vehicle event, for instance a change in a hybrid range state or a control gain reduction event, and then automatically resets the integral control torque term(s) for the physical target value during the requested vehicle event to thereby maintain the total control torque for the same target value through the execution of the predetermined vehicle event.

Abstract: A method for controlling operation of an electro-mechanical transmission configured to transfer torque among an input member, a plurality of torque machines and an output member includes determining an engine pulse torque, calculating a first motor torque pulse command based upon a first transfer function between the engine pulse torque and a torque command for a first torque machine and the engine pulse torque, calculating a second motor torque pulse command based upon a second transfer function between the engine pulse torque and a torque command for a second torque machine and the engine pulse torque, and controlling the first torque machine in response to the first motor torque pulse command and controlling the second torque machine in response to the second motor torque pulse command.

Abstract: A hybrid powertrain system includes a transmission device operative to transfer power between an input member, a torque machine and an output member, the output member coupled to a driveline coupled to a wheel to transfer tractive torque therebetween. A method for controlling the hybrid powertrain system includes monitoring an operator torque request, determining an operating range state of the transmission device, determining a net output torque to the output member based upon the operator torque request, determining a lash state of the driveline, and determining a command for transferring output torque to the output member based upon the operating range state of the transmission device, the net output torque, and the lash state of the driveline.

Abstract: A method for optimizing a shift event in a vehicle includes designating a clutch to be used as an oncoming clutch or an offgoing clutch in the shift event before executing the shift event, and processing a plurality of input values through a state observer to thereby determine, as an output value of the state observer, an estimated slip speed of the designated clutch. The method includes using a proportional-integral control module for the designated clutch (a clutch PI) to close the control loop on the estimated slip speed from the state observer, thereby smoothing a switching between state space equations in the state observer, and executing the shift event. A vehicle includes a transmission, an engine, at least one traction motor, and a control system configured for executing the above method.

Abstract: A method for analysis of a prototype graphical user interface (GUI) comprising the following steps: receiving, with a processor, a computer code representative of the prototype GUI, wherein the prototype GUI comprises GUI elements having known identities and known behavioral attributes; transforming the computer code into a description of visible sub-elements of the prototype GUI elements, wherein each sub-element has visual properties that would be visible to a user of the prototype GUI; grouping particular visible sub-elements into a perceived GUI element based only on the sub-elements' visual properties according to a grouping algorithm without regard to the known identity(ies) of the prototype GUI element(s) to which the particular sub-elements belong; and storing, in a non-transitory first memory store, the perceived GUI element.

Abstract: A powertrain including an engine and torque machines is configured to transfer torque through a multi-mode transmission to an output member. A method for controlling the powertrain includes employing a closed-loop speed control system to control torque commands for the torque machines in response to a desired input speed. Upon approaching a power limit of a power storage device transferring power to the torque machines, power limited torque commands are determined for the torque machines in response to the power limit and the closed-loop speed control system is employed to determine an engine torque command in response to the desired input speed and the power limited torque commands for the torque machines.

Abstract: A method for controlling a multi-mode transmission system employing torque machines under dynamic operating conditions includes calculating a phase shift between a control parameter of one of the torque machines and a response parameter of the multi-mode transmission system under dynamic operating conditions, comparing the calculated phase shift and an expected phase shift, and executing remedial action when the calculated phase shift exceeds a threshold associated with the expected phase shift.

Abstract: A powertrain system including a multi-mode transmission is configured to transfer torque among an input member, torque machines and an output member. A method for controlling the multi-mode transmission includes employing a closed-loop speed control system to determine torque commands for physical torque actuators including the torque machines. The closed-loop speed control system includes employing a virtual torque actuator control scheme to generate torque commands for the physical torque actuators responsive to output commands for a plurality of virtual torque actuators.

Abstract: A method for controlling operation of an electro-mechanical transmission configured to transfer torque among an input member, a plurality of torque machines and an output member includes determining an engine pulse torque, calculating a first motor torque pulse command based upon a first transfer function between the engine pulse torque and a torque command for a first torque machine and the engine pulse torque, calculating a second motor torque pulse command based upon a second transfer function between the engine pulse torque and a torque command for a second torque machine and the engine pulse torque, and controlling the first torque machine in response to the first motor torque pulse command and controlling the second torque machine in response to the second motor torque pulse command.

Abstract: A method for optimizing torque control in a vehicle having a controller and a rotating member includes generating a closed-loop total proportional torque command using a state space feedback portion of the controller, and splitting the total proportional torque command into high-frequency and low-frequency proportional torque components. A total proportional torque is passed to the rotating member to provide driveline damping control when speed control is not required. The high-frequency proportional torque component is passed to the rotating member to provide driveline damping control, and the low-frequency torque component is passed with a total integral torque command to the rotating member to provide speed control, when speed control is required. A vehicle includes a controller having proportional-integral control capabilities and a state space observer, and a powertrain having a rotating member whose speed and damping characteristics are controlled by the controller.

Abstract: 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.

Abstract: 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.

Abstract: An example vehicle includes a motor and a gearbox. A controller is configured to identify oscillation peaks of a performance signal representing the rotational speed of the motor, the input speed of the gearbox, or the amount of torque generated by the motor or provided to the gearbox. The controller is configured to simultaneously detect unstable regular and irregular oscillations of the performance signal given the oscillation peaks identified and substantially dampen the unstable oscillations detected. An example method may include determining a mean of the performance signal and defining peak values, including peak moving average values or filtered peak values, representing a magnitude of at least two oscillation peaks. The method further includes simultaneously detecting the unstable regular and irregular oscillations of the performance signal using the defined values and substantially dampening the unstable oscillations.

Abstract: A powertrain system includes a torque machine mechanically rotatably coupled via a transfer gear set to a drive wheel. The transfer gear set includes a first gear meshingly engaged to a second gear with lash angle between the first and second gears. A method for operating the powertrain system includes monitoring an output speed associated with the torque machine and a wheel speed associated with the drive wheel. A transition between a first torque transfer state and a second torque transfer state is detected, the transition including a gear lash event across the transfer gear set. An elapsed time period for completing the gear lash event across the transfer gear set during the transition between the first torque transfer state and the second torque transfer state is set, and a target output speed derived from the wheel speed during and at the end of the elapsed time period is determined.

Abstract: A method to predict a driveline lash condition includes monitoring an axle torque request signal, determining a predicted axle torque request value at a lead time based upon the monitored axle torque request signal, and predicting the driveline lash condition at the lead time based upon the predicted axle torque request value indicating an upcoming zero torque condition.

Abstract: A vehicle includes a traction motor, a transmission, a speed encoder for the motor, and a control system. The control system compensates for angular wobble in an encoder signal. The control system receives, via a hybrid control processor (HCP), the encoder signal from the speed encoder, and determines a set of wobble characteristics of the encoder signal below a threshold motor speed. The control system also calculates a wobble-compensated speed value via the HCP using the wobble characteristics, and uses the wobble-compensated speed value as at least part of the input signals when controlling the motor. A lookup table tabulates a learned wobble value relative to the angular position value, and a learned wobble value is subtracted from a current angular wobble value to generate an error-adjusted wobble value. A method compensates for wobble in the encoder signal using the above control system.