Hi everyone!

We've been using the nav stack on our Roombas for quite a while now, mostly on the corridors of ISR without any problems.

However we have a small 4mx3m arena we built specifically for testing odor search algorithms in which we recently started to run some experiments. We quickly found out that the nav stack has some problems moving the robot around in tight places. Quite often we get the behavior that can be seen in the following video...

http://www.youtube.com/watch?v=vy9xoNvmktg

In the video we are running a Roomba inside our arena in Stage with perfect odometry. The robot stalls against a wall and stays there for 30mins until we stop it. On occasion the robot eventually gets out after a while.

At first I thought this could be happening because of the poor performance of the EeePCs the Roombas carry around or because of the Roomba's crappy odometry, but in Stage on a Core2Duo laptop we were able to see the same behavior.

Has anyone experienced this behavior before?