Nonparametric Driveline Identification and Control

A nonparametric identification and control approach to active driveline control is investigated. A nonlinear model incorporating nonlinear clutch characteristics and driveline backlash is developed. An approach using short time Fourier transforms for nonparametric frequency response identification and smoothing is presented. The identification method is used to identify a driveline model both with and without backlash present. Two nonparametric controller design techniques are employed. A parameter space method is used to design a PI controller and an analytic-optimisation mixed sensitivity H_¿ method to design a high order controller for the cases with and without backlash. The controllers designed for the system without backlash proved unstable when applied to the system with it present. In contrast, both the PI controller and the higher order controller from the new technique give good control of the fully nonlinear driveline. The new approach should be directly applicable to experimentally produced time series data, which potentially allows a systematic controller calibration without the need for extensive in-vehicle tuning.