Vehicle powertrain control system

A vehicle comprising:

• a transmission having an input shaft and an output shaft;
• an engine configured to generate and deliver torque to the input shaft;
• a disconnect clutch configured to connect and disconnect the engine from the input shaft, and to crank the engine during an engine start;
• an inertial measurement unit configured to measure inertial forces exerted onto the vehicle;
• and
• a controller programmed to, in response to a command to adjust a torque of the disconnect clutch to a desired value that is derived from the inertial forces and a vehicle velocity, drive a clutch actuator pressure to a value that corresponds to the desired value.

A vehicle comprising:

• a transmission having an input and an output;
• an engine and an electric machine, each configured to generate and deliver torque to the input;
• a disconnect clutch configured to connect and disconnect the engine from the input, and to crank the engine during an engine start;
• an inertial measurement unit configured to measure inertial forces exerted onto the vehicle;
• and
• a controller programmed to,
• in response to a demanded torque at the output, control the torque at the output based on a mapped relationship between the inertial forces and a vehicle velocity,
• in response to a command to start the engine, close the disconnect clutch to start the engine, calculate the torque of the disconnect clutch based on the controlled torque at the output and an electric machine torque, and map the relationship between the torque of the disconnect clutch and a clutch actuator pressure to derive or adjust a gain value and an offset value of a transfer function that represents the relationship between the torque of the disconnect clutch and the clutch actuator pressure, and
• in response to a command to adjust the torque of the disconnect clutch to a desired value, adjust the clutch actuator pressure to a value that corresponds to the desired value according to the transfer function.