A Powertrain LQR-Torque Compensator with Backlash Handling

This paper derives an LQR anti-jerk controller for an automotive driveline. The time derivative of the drive shaft torque, which is closely related to the vehicle jerk, is used as a virtual system output and regulated to zero. Thereby, the controller does not need a reference model for generation of reference trajectories for the control law evaluation. The controller acts as a torque compensator for the driver’s torque demand which the controller output asymptotically follows. The properties of the controller are discussed and the behavior is illustrated by simulation examples and verified with experiments on a heavy duty truck.