Abstract
With increasing complexity of engine management system there is a tendency for traditional driving cycles to become further and further removed from reality. So for a sensible evaluation of emissions and fuel consumption of road vehicles in the field there is an urgent need for 'real-world' driving patterns. Existing 'standard' driving cycles can be shown to be uncharacteristic of real- world driving behaviour. A methodology is presented to characterise real-world driving patterns numerically. On the basis of this methodology an overview is given of characteristic driving behaviour of various categories of road vehicle (trucks, passenger cars and motorcycles) in different regions of the world. Where relevant, these examples are compared with the different traffic conditions in those regions. Finally some examples are given of the way in which the study of real-world driving patterns can influence a national emission inventory, by taking into account off-average driving behaviour and off-average traffic conditions.