Fuel and ride comfort optimization in heavy vehicles

Abstract: In modern heavy vehicles low fuel consumption as well as good ride comfort and driveability is desired. Assuming that the road altitude ahead of the vehicle is known the optimal control regarding fuel and time consumption can be calculated. However this results in a bang-singular-bang control which decreases the ride comfort by introducing high jerk levels and oscillations in acceleration as well as jerk originating from the dynamics in the driveline. In this thesis several methods to supress these behaviours are presented. A qualitative study of the methods impact on ride comfort as well as fuel and time consumption is carried out. A driveline model is implemented in Simulink and used for the evaluations. The aim is not to find a optimal strategy but rather to suggest methods and evaluate these as far as can be done in simulation to enable for future test runs.