Determination of the position of the contact point of a tire model with an uneven road surface for purposes of vehicle dynamical analysis

Two algorithms which allow one to take an uneven road surface into account in the vehicle
dynamics analysis are presented in the article. Their essence is to determine the position of
the contact point of the tire model with the uneven road surface. According to the concept
of the authors, the names of the algorithms are to refer to the essence of the matter of
the procedures assumed. The first of them – named Plane – can be used while considering
the continuous model of the surface obtained by use of “the bicubic interpolation” taken
from computer graphics, and the second one – named 4Points – in the case of the discrete
model of this surface, developed especially for needs of the methods presented. In the work,
it is assumed that only continuous changes of the road profile, without its possible abrupt
changes, e.g. in form of a transversely placed threshold of sharp edges, can be considered.
Therefore, the mapping of the road surface, obtained in the case of including its both models,
is smooth. The developed algorithms are used to analyze dynamics of a technical rescue
vehicle which can drive in terrain conditions.