Mobile robot navigation is a very important task in all robot applications from domestic service cleaning machine to highly sophisticated industrial robotic applications. In this paper, we investigated, and evaluated the well-known A* path planning algorithm. The standard A* algorithm is capable of finding out the most optimal path of the robot. A grid-based map obtained from the vision-based obstacle detection system in [2] as an input to the A* algorithm. Standard A* does not take the size of the robot into consideration which could produce unsafe paths for the robot to follow and collision could be occurs. Our proposed modified A* algorithm takes the robot size as a parameter to generate a safer path for the robot and avoid sharp turns. The Direction of Arrival (DOA) is used as a restriction to the path planning process which is a requirement in some robotic applications.