The recent introduction of stringent emission
requirements together with economic pressure has led
to a particular focus on increasing powertrain
efficiency. This has seen the incorporation of
real-time measurements to predict system behaviour
and engine condition. Accurate models for all
components are thus important. This work investigates
the consequences of some common assumptions made in
low frequency torsional powertrain models, and
proposes improved models where appropriate. In
particular, piston-to-cylinder friction,
(crank/gudgeon) offset, and tyre torsional behaviour
were studied....