Patent ID: 8989971
Filing Date: 2015-03-24
Classification: F16H,G01L

Abstract:
1. A system for controlling pressure in a transmission comprising: a valve for regulating operation of a hydraulic device; a pressure transducer for detecting an output pressure of the valve, the pressure transducer configured to output a pressure reading representing the detected pressure for a range of pressures both below and above a predetermined threshold pressure and to communicate the detected pressure for each of the pressures, a first pressure reading taken at an operating condition in which the actual output pressure of the valve is substantially known; a microprocessor comprising logic for computing a pressure measurement error of the pressure transducer and a corrected pressure reading, the pressure measurement error computed using the first pressure reading and the substantially known actual output pressure of the valve and the corrected pressure reading computed using a first variable comprising a second pressure reading received from the pressure transducer taken subsequent to the first pressure reading, and a second variable comprising the previously computed pressure measurement error; and a valve controller for controlling the operation of the valve, the valve controller configured to receive as input from the microprocessor the corrected pressure reading and to output a control signal used to control the operation of the valve, the control signal formulated using the corrected pressure reading received from the microprocessor; and a transmission control unit configured to receive as input from the microprocessor the previously computed pressure measurement error, the transmission control unit comprising logic for computing an adjusted command pressure computed using a desired pressure to be output from the valve and the previously computed pressure measurement error received from the microprocessor.