Up to date, application areas of mobile robots have been expanded. In addition, many types of Laser Range Finder(LRF) systems have been developed to acquire three dimensional information about unknown environments. However in real world, because of various noises (sunlight, fluorescent light), it is difficult to separate reflected laser light from these noises. For that reason, working areas of mobile robots are constrained. To overcome the previous restriction, we have developed a new type vision system which enables a mobile robot to measure the distance to a natural object located 1-5(m) ahead with an error less than 2%. The separation and detection algorhithm used in this system consists of pulse phase difference method which is useful to separate reflected laser light from the noises and multi-stripe structured light which can reduce computation time. The experimental facility consists of a He-Ne laser, two CCD cameras, optical filter, and a personal computer. The effectiveness and feasibility of the proposed vision system are demonstrated by 3-D maps of detected objects and computation time analysis.
