According to the characteristics of wheeled mobile robots

a novel method for real-time local two dimension(2D) map building based on binocular vision is proposed. Firstly

the principle of virtual height lines imaging in binocular vision system is proposed. The scene is partitioned into uniform grids

and virtual height line segments(VHLS) which do not exist in the scene are introduced. Each VHLS was projected into the stereo images in binocular vision system and formed a projection line segment(PLS).Finding the height of the scene is converted to finding the correspondence that has the maximum similarity metric on the PLS and in the searched horizontal disparity range. Then

a novel local 2D map building method is proposed. Similarity metric of the scene on the part of the PLS whose height is greater than the maximum which robots can overleap

is to determine whether the scene grid is an obstacle region or not. The experiment results show that the proposed method is valid and real-time for mobile robots

and can be used for building three dimension(3D) map.