Method of learning for adaptively controlling an electronic automatic transmission system

In a vehicle having an engine and a transmission system including an input member, an output member, a torque converter assembly for transmitting torque between the engine and the input member, a gear assembly for changing the ratio of torque between the input member and output member, a plurality of friction elements for shifting the gear assembly, a fluid actuating device being moveable for applying at least one friction element, at least one solenoid-actuated valve being moveable in response to the presence or absence of electrical power to the valve for directing fluid flow between a fluid source and the fluid actuating device, input sensors providing input signals indicative of predetermined conditions, a controller having memory for processing and storing the input signals and predetermined values and providing output signals to control the solenoid-actuated valves, a method of monitoring an output and adjusting the action effecting the output continuously in a vehicle transmission, said method comprising the steps of:

• monitoring the speed of a turbine in a torque converter assembly;
• monitoring the instantaneous fluid volume of a friction element;
• setting a learned volume value equal to an instantaneous fluid volume value indicative of the instantaneous fluid volume when the time to nearly fill the friction element is approximately zero;
• re-setting the learned volume value equal to the instantaneous fluid volume value whenever slip is detected;
• comparing the learned volume value to a stored fill volume value in memory at the end of the shift;
• and
• adjusting the stored fill volume value based on the difference between the learned volume value and the stored fill volume value.

In a transmission system including an input member, an output member, a gear assembly for changing the ratio of torque between the input member and output member, a plurality of friction elements for shifting the gear assembly, a fluid actuating device being moveable for applying at least one friction element, at least one solenoid-actuated valve being moveable in response to the presence or absence of electrical power to the valve for directing fluid flow between a fluid source and the fluid actuating device, input sensors providing input signals indicative of predetermined conditions, a controller having memory for processing and storing the input signals and predetermined values and providing output signals to control the solenoid-actuated valves, a method of monitoring an output and adjusting the action effecting the output continuously in the transmission system, said method comprising the steps of:

• monitoring the speed of an input member;
• monitoring the instantaneous fluid volume of a friction element;
• setting a learned volume value equal to an instantaneous fluid volume value indicative of the instantaneous fluid volume whenever the monitored speed of the input member is within a predetermined range of a predetermined speed;
• comparing the learned volume value to a stored fill volume value in memory at the end of the shift;
• and
• adjusting the stored fill volume value based on the difference between the learned volume value and the stored fill volume value.