Determining oncoming clutch pressure in a transmission

A vehicle comprising:

• an internal combustion engine;
• an automatic transmission having an input member that is connected to the engine and a pair of clutches;
• and
• a controller in communication with the engine and the transmission, wherein the controller includes:
• a processor;
• and
• a tangible, non-transitory memory device on which is recorded instructions for determining the clutch pressure of an oncoming clutch during an upshift in an automatic transmission, and on which is recorded proportional-integral-derivative (PID) feedback control logic;
• wherein execution of the instructions by the processor causes the controller to:
• determine when an offgoing clutch and an oncoming clutch of the transmission have neared a speed synchronization point to within a calibrated window;
• activate the PID feedback control logic for the oncoming clutch;
• introduce, using the activated PID logic, a calibrated slip error between the rotational speeds of the offgoing and the oncoming clutches;
• hold engine speed in a calibrated flare using the PID logic;
• record the oncoming clutch pressure during the duration of the calibrated flare in the memory device;
• and
• execute a control action with respect to the transmission using the recorded oncoming clutch pressure.

A system for use within a vehicle having an internal combustion engine, the system comprising:

• an automatic transmission having a pair of clutches and an input member that is connectable to the engine;
• and
• a controller in communication with the transmission, wherein the controller includes:
• a processor;
• and
• a tangible, non-transitory memory device on which is recorded instructions for determining the clutch pressure of an oncoming clutch during an upshift of the transmission, and on which is recorded proportional-integral-derivative (PID) feedback control logic;
• wherein execution of the instructions by the processor, when the transmission has been connected to the engine in the vehicle, causes the controller to:
• determine when an offgoing clutch and an oncoming clutch of the transmission have neared a speed synchronization point to within a calibrated window;
• activate the PID feedback control logic for the oncoming clutch;
• introduce, using the activated PID logic, a calibrated slip error between the rotational speeds of the offgoing and the oncoming clutches;
• hold engine speed in a calibrated flare using the PID logic;
• record the oncoming clutch pressure during the duration of the calibrated flare in the memory device;
• and
• execute a control action with respect to the transmission using the recorded oncoming clutch pressure.