Improved single-camera stereo system for mobile robotics

A single-camera stereo vision system offers a greatly simplified approach to image capture and analysis. In the original study by Lovegrove and Brame, they proposed a novel optical system that uses a single camera to capture two short, wide stereo images that can then be analyzed for real-time obstacle detection. In this paper, further analysis and refinement of the optical design results in two virtual cameras with perfectly parallel central axes. A new prototype camera design provides experimental verification of the analysis and also provides insight into practical construction. The experimental device showed that the virtual cameras' axes possessed a deviation from parallel of less than 12 minutes (or 0.2 degrees). The calculation of distances to objects from the two overlapping images all showed errors smaller than the pixel resolution limitation. In addition, a barrel lens correction was used in processing the image to allow parallax distance determination in the whole horizontal view of the images.