Sensors Hate Dark Surfaces

Previously I've mentioned my issues with the low cost Hokuyo URG-04LX-UG01, even going so far as to say that the laser in the Neato XV-11 robot was better. One of the major differences between Maxwell and his little Armadillo cousin is that on Maxwell I have mounted the laser about 6" off the ground, versus the 2" of the Armadillo. Interestingly, this has had a huge impact on performance -- our walls here in the lab are mostly white, and the laser works much better on the walls than the black base trim:

I've also found that the same black paint is on our doors, and wreaks havoc on the Kinect. The image below shows the RGB point cloud -- this is a Sunday, both doors are shut, yet invisible:

Luckily, it looks like the laser picks up the doors when close, so I won't have to worry about Maxwell driving through an invisible doorway.