  It is suggested that the motion of pedestrians can be described as if they
would be subject to `social forces'. These `forces' are not directly exerted by
the pedestrians' personal environment, but they are a measure for the internal
motivations of the individuals to perform certain actions (movements). The
corresponding force concept is discussed in more detail and can be also applied
to the description of other behaviors.
  In the presented model of pedestrian behavior several force terms are
essential: First, a term describing the acceleration towards the desired
velocity of motion. Second, terms reflecting that a pedestrian keeps a certain
distance to other pedestrians and borders. Third, a term modeling attractive
effects. The resulting equations of motion are nonlinearly coupled Langevin
equations. Computer simulations of crowds of interacting pedestrians show that
the social force model is capable of describing the self-organization of
several observed collective effects of pedestrian behavior very realistically.
