HOKUYO UTM-30LX: I saw this Hokuyo model during ICRA'10 and it seemed to work pretty well in the expo section. They promised me at the stand that it would work well in outdoor conditions despite light changes and noise. It costs twice what your regular Hokuyo would, but it is much cheaper and easier to use than stereoscopy or single-camera disparity range calculation. Might be worth a try!

• 25ms per scan
• Low power comsumption 8.4W
• Power source 12Vdc @700ma
• High accuracy ± 30mm
• 240° Scanning area
• High resolution 0.25°
• Compact W:60, D:60, H87mm
• Light weight 370g
• USB 2.0 (Full Speed)
• Range: 20 to 30,000mm