Patent ID: 8296024
Filing Date: 2012-10-23
Classification: B60W,F16H,Y10T

Abstract:
1. A method of calibrating a transmission for open loop torque control operation, the transmission having a variator, the variator having an actuator and an output, the variator further having an internal circuit pressure, the method comprising: engaging the transmission in neutral, such that the variator output experiences substantially zero torque; with the transmission in neutral, commanding hydraulic pressure to the variator actuator to identify a displacement correlation between commanded hydraulic pressure to the actuator and variator displacement; engaging the transmission into a mode wherein the variator provides a fixed output speed regardless of circuit pressure; commanding hydraulic pressure to the variator actuator to identify a circuit pressure correlation between commanded hydraulic pressure and variator circuit pressure; and using the displacement correlation and circuit pressure correlation to control the transmission using feed forward torque control.