Abstract: A vehicular powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine. A method for operating the powertrain includes monitoring operator inputs, monitoring a transmission output, and terminating an engine operating mode when a time-rate change in the transmission output exceeds a threshold absent a change in the monitored operator inputs.

Abstract: A system for robust fault detection in an electrically variable, hydraulically controlled transmission includes independently monitoring hydraulic pressure within a hydraulic control circuit and electric machine rotation for detecting clutch state faults.

Abstract: Control of operation of a hybrid powertrain is provided, wherein mechanical power flow to an output is controlled through selective actuation of torque-transfer clutches. Electric machines are coupled to an energy storage system for electric power flow. The electro-mechanical transmission is operated in a continuously variable operating range state, and, operation of the transmission is monitored. Absence of a mismatch between the commanded continuously variable operating range state and an actual operating state of the transmission is determined. Presence of a mismatch between the commanded operating range state and the actual operating state of the transmission may be determined. Operation of the powertrain is modified when a mismatch between the commanded operating range state and the actual operating state of the transmission is detected.

Abstract: A powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine to selectively transmit mechanical power to an output member. Powertrain operation includes monitoring operator inputs, and determining input speeds and changes in input speeds for the internal combustion engine and the electric machine. The input speeds are compared to threshold input speeds, and the changes in input speeds are compared to threshold changes in input speeds. Input torques of the internal combustion engine and the electric machine are reduced when any one of the input speeds and changes in input speeds exceeds the corresponding threshold.

Abstract: A vehicular powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine. A method for operating the powertrain includes monitoring operator inputs, monitoring a transmission output, and terminating an engine operating mode when a time-rate change in the transmission output exceeds a threshold absent a change in the monitored operator inputs.

Abstract: A method for operating the powertrain includes monitoring operator inputs, monitoring a transmission output, and terminating an engine operating mode when a time-rate change in the transmission output exceeds a threshold absent a change in the monitored operator inputs.

Abstract: There is provided a method to monitor a sensing system adapted to monitor an output of an electro-mechanical transmission. This includes monitoring rotational speed of a wheel operatively connected to a driveline operatively connected to the output of the electro-mechanical transmission. A first expected output of the transmission is determined based upon the output of the first sensor. A second expected output of the transmission is determined based upon a rotational speed of a torque-generative device operatively connected to the transmission. The first and second expected outputs and an output of the sensing system adapted to monitor the output of the electro-mechanical transmission are compared.

Abstract: A system for robust fault detection in an electrically variable, hydraulically controlled transmission includes independently monitoring hydraulic pressure within a hydraulic control circuit and electric machine rotation for detecting clutch state faults.

Abstract: Monitoring operation of an electro-mechanical transmission having a hydraulic circuit with flow management valves and pressure control solenoids to actuate clutches and pressure monitoring devices to monitor the hydraulic circuit is provided. The transmission operates in fixed gear and continuously variable operating range states. The method comprises controlling position of one of the flow management valves to control operation in one of the operating range states. A fault is detected in the one of the flow management valves based upon outputs of the pressure monitoring devices during steady state operation in one of the continuously variable operating range states. A fault is detected in the one of the flow management valves based upon the output of one of the pressure monitoring devices during a transition in the flow management valve.

Abstract: A flow management valve is operative to enable a multi-range electro-mechanical transmission in first and second ranges. Fluid pressure in a hydraulic circuit is monitored to detect a fault in the flow management valve.

Abstract: A system for robust fault detection in an electrically variable, hydraulically controlled transmission includes independently monitoring hydraulic pressure within a hydraulic control circuit and electric machine rotation for detecting clutch state faults.

Abstract: Temperature of an electric power device of a hybrid transmission is managed based upon device temperatures and power flow, ambient temperature, and a cooling circuit flow rate.

Abstract: A method for detecting speed faults in a hybrid powertrain having engine and electric machine speed inputs includes directly sensing the engine and machine speeds and performing comparisons of sensed engine speed with engine speed determined based upon the machine speeds.

Abstract: A powertrain includes an electro-mechanical transmission mechanically-operatively coupled to an internal combustion engine and an electric machine to selectively transmit mechanical power to an output member. Powertrain operation includes monitoring operator inputs, and determining input speeds and changes in input speeds for the internal combustion engine and the electric machine. The input speeds are compared to threshold input speeds, and the changes in input speeds are compared to threshold changes in input speeds. Input torques of the internal combustion engine and the electric machine are reduced when any one of the input speeds and changes in input speeds exceeds the corresponding threshold.

Abstract: A method for detecting speed faults in a hybrid powertrain having engine and electric machine speed inputs includes directly sensing the engine and machine speeds and performing comparisons of sensed engine speed with engine speed determined based upon the machine speeds.

Abstract: A flow management valve is operative to enable a multi-range electro-mechanical transmission in first and second ranges. Fluid pressure in a hydraulic circuit is monitored to detect a fault in the flow management valve.

Abstract: Temperature of an electric power device of a hybrid transmission is managed based upon device temperatures and power flow, ambient temperature, and a cooling circuit flow rate.

Abstract: Control of operation of a hybrid powertrain is provided, wherein mechanical power flow to an output is controlled through selective actuation of torque-transfer clutches. Electric machines are coupled to an energy storage system for electric power flow. The electro-mechanical transmission is operated in a continuously variable operating range state, and, operation of the transmission is monitored. Absence of a mismatch between the commanded continuously variable operating range state and an actual operating state of the transmission is determined. Presence of a mismatch between the commanded operating range state and the actual operating state of the transmission may be determined. Operation of the powertrain is modified when a mismatch between the commanded operating range state and the actual operating state of the transmission is detected.

Abstract: A system for robust fault detection in an electrically variable, hydraulically controlled transmission includes independently monitoring hydraulic pressure within a hydraulic control circuit and electric machine rotation for detecting clutch state faults.

Abstract: Monitoring operation of an electromechanical transmission having a hydraulic circuit with flow management valves and pressure control solenoids to actuate clutches and pressure monitoring devices to monitor the hydraulic circuit is provided. The transmission operates in fixed gear and continuously variable operating range states. The method comprises controlling position of one of the flow management valves to control operation in one of the operating range states. A fault is detected in the one of the flow management valves based upon outputs of the pressure monitoring devices during steady state operation in one of the continuously variable operating range states. A fault is detected in the one of the flow management valves based upon the output of one of the pressure monitoring devices during a transition in the flow management valve.