1. A method for mapping an environment containing dynamic obstacles comprising the steps of: forming a current instantaneous map of the environment using a processor; determining free cells which are free-space within the current instantaneous map using the processor; determining occupied cells which are occupied-space within the current instantaneous map using the processor; and forming a new integrated map using the processor by integrating the current instantaneous map of the environment with an old integrated map of the environment, the forming including marking cells in the new integrated map as free-space or occupied-space based on the corresponding cells in the current instantaneous map and marking some of unmarked cells in the new integrated map as free-space based at least on the some of the unmarked cells being disposed along a line between a first cell and a second cell, the line being substantially perpendicular to a ground plane.