Abstract:
This
study is an investigation into the use of computer aided handling and stability
analysis for motorcycles. In particular it considers Triumph Motorcycles Ltd., delving
into
Triumph's background, their strategy and the likelihood of them using virtual
techniques for stability and handling analysis.
Additionally, this work reviews current knowledge of motorcycle dynamics analysis
and builds on it.
A novel way of studying the steering feel has been developed by analysing the response
of the steer torque equation for the Sharp 1971 [1] and 1994 [2] models. The individual
contributors to this
equation are identified and the important ones are investigated
further. One conclusion of this study is that in reduced cornering and camber conditions
the steer
angle of the motorcycle, for a given steering input torque, increases when
compared to standard operating conditions. The steer angle also increases further as the
speed increases.
An update to a previous motorcycle model [3] has been made by revising the parameter
set, so that it is more applicable to a modem sports motorcycle. The rider model and
relaxation
length description have also been improved upon. The results show that the
new motorcycle has been made more manoeuvrable by the alterations to the parameters.
An optimal preview steering control system for cars [4] has been taken, improved upon
and used with the
newly developed motorcycle model discussed above. The results
from this novel work allow a designer to alter parameters and see how this affects the
motorcycles steering demands, path following, etc. It was shown that an increase in
the front wheel inertia makes the
motorcycle feel like the steering is heavier, and an
increase in the front wheel radius and wheelbase make the
steering feel lighter.
Future work into non-linear
analysis is recommended and improved rider and tyre
modelling is also desired.