Patent ID: 8606476

Claim:
A vehicle comprising: an engine; a transmission operatively connected to the engine, and having: a clutch having a clutch pack; a piston which is movable via pressurized fluid to apply a force to actuate the clutch pack; and a clutch position sensor positioned with respect to the clutch piston, wherein the clutch position sensor measures a changing magnetic field with respect to the clutch piston as the clutch piston moves with respect to the clutch pack, and then encodes the measured magnetic field as a raw position signal of the piston; and a controller which controls actuation of the clutch using a filtered position signal; wherein the controller includes a microprocessor and tangible, non-transitory memory on which is recorded computer-executable code, wherein the controller is in communication with the clutch position sensor, and is configured to execute the code to thereby: receive the raw position signal from the clutch position sensor and generate the filtered position signal to thereby attenuate signal noise in the raw position signal; determine a commanded position signal of the piston; calculate an instantaneous error value between the filtered position signal and the commanded position signal; calculate separate proportional (P), integral (I), and derivative (D) clutch flow control terms using the instantaneous error value; calculate a feed-forward clutch flow control term as a function of the commanded position; calculate a required flow rate for actuating the clutch pack as a function of the PID clutch flow control terms and the feed-forward clutch flow control term; and control an actuation of the clutch pack using the required flow rate.