Closed-loop clutch control of an automatic shift transmission

摘要

An improved closed-loop transmission shift control in which the pressures are regulated in a manner to accelerate/decelerate the input and output shafts or the transmission in relation the progression of the shift. The control requires dynamic knowledge of the transmission input and output torques, and the preferred mechanization of the present invention employs an estimation of the input and output torque effects so that the control is carried out with only input and output shaft speed measurements. The estimations are adjusted based on the difference between the expected and actual input and output shaft speed values, so as to compensate for torque control errors as well as torque estimation errors.