Main objective of the perception module is to detect all obstacles in the vehicle path, to identify obstacle location in the global coordinates, and to pass through the correct obstacle information to the motion planning algorithm. Our car-like robot is operated in outdoor environment. In this section, the global coordinate’s system and ECEF transformation equation are presented for evaluating obstacles’ location relative to the global fixed environment. Furthermore, a fixed grid map is constructed as a place holder for obstacle locations. In the last part, a specify threshold is applied to a probability of obstacle occurrence in the global occu-pancy-grid map to provide more accurate obstacle locations.