The motivation behind this work is to develop a dynamical systems unde
rstanding of the phenomenon of squeal. Squeal is a form of self-excite
d vibration; vibrations are induced in a structure such as a wheel or
violin string by the action of a frictional driving force. The nature
of this force is rather difficult to define; however, a phenomenologic
al model is proposed which combines the concepts of static and dynamic
friction, which seems intuitively reasonable and for which there is d
ocumented evidence. In the case presented here, the vibrating structur
e is simplified to that of a block resting on a moving conveyor belt,
restrained by a simple spring and dashpot to a rigid wall. The non-lin
ear system dynamics predicted by using the new friction model are unus
ual in that the conditions giving rise to squeal include not only the
belt speed, but also the initial conditions of the structure. It is th
ought that this information may be useful in the control of the onset
of squeal. (C) 1997 Academic Press Limited.