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Modern vehicles require a high degree of refinement, including good driveability, to meet customer demands. Specific aspects of driveability can be improved through the use of modern control techniques. This paper describes work by Ricardo on a novel active driveability control algorithm to reduce unwanted fore and aft oscillations in vehicle acceleration, known as shuffle, following a change in accelerator pedal position. The control algorithm is derived from a linearized model of the vehicle drivetrain and comprises two elements; a state observer estimating values of unmeasurable variables in the powertrain from standard production sensors and a state feedback controller to modulate engine torque. Together, these two elements increase the damping factor of the powertrain at critical frequencies and hence reduce vehicle shuffle.

Vehicle energy consumption and emissions can be predicted via drive cycle simulation. The complexity of existing and future vehicles necessitates the use of a simulation tool to aid in this work. A library of modules has been written that represents elements of powertrains found in conventional, electric and hybrid vehicles. The library makes use of the SIMULINK simulation environment. It allows users to quickly and easily develop complex models. These simulation models can be used to predict a vehicle's performance, fuel consumption, electrical consumption and emissions.