  This paper presents a methodology that aims at the incremental representation
of areas inside environments in terms of attractive forces. It is proposed a
parametric representation of velocity fields ruling the dynamics of moving
agents. It is assumed that attractive spots in the environment are responsible
for modifying the motion of agents. A switching model is used to describe near
and far velocity fields, which in turn are used to learn attractive
characteristics of environments. The effect of such areas is considered radial
over all the scene. Based on the estimation of attractive areas, a map that
describes their effects in terms of their localizations, ranges of action, and
intensities is derived in an online way. Information of static attractive areas
is added dynamically into a set of filters that describes possible interactions
between moving agents and an environment. The proposed approach is first
evaluated on synthetic data; posteriorly, the method is applied on real
trajectories coming from moving pedestrians in an indoor environment.
