Estimation of Turbine Torque of Automatic Transmissions Using Nonlinear Observers

This paper presents an adaptive sliding observer-based method for estimation of turbine torque. The estimated turbine torques can be used for the closed-loop control of vehicle power train for better shift quality. A sliding observer structure including saturation functions and boundary layers is applied to adapt torque converter parameters. The proposed method has been investigated via simulation and laboratory experimental studies. It has been shown via simulation and experiments that the proposed methodology is promising for the estimation of turbine torques since it uses only inexpensive angular velocity measurements and is not sensitive to parametric uncertainties. [S0022-0434(00)00302-6]