I had a similar problem with my Roomba. Recently it began to bump into phantom walls where there were none, to the point where it would get stuck in the middle

I had a similar problem with my Roomba. Recently it began to bump into phantom walls where there were none, to the point where it would get stuck in the middle of the floor, turning around and around, stuck in a jail of invisible walls. The Roomba detects this problem and emits a failure code of 9 beeps. I contacted iRobot about the problem, and their response was to ship me a fresh Roomba (without the battery + charging station) right away. Here are some pictures of the battery transplant: http://dl.dropbox.com/u/1149620/roombasurgery/index.html http://dl.dropbox.com/u/1149620/roombasurgery/index.html From the troubleshooting instructions that iRobot gives you upon encountering the 9-beep code, I suspect that there's probably just a faulty or possibly dirty (likely very inexpensive) sensor on the front bumper of the robot. I wonder if there's a similar fix to jwz's Roomba where I could patch for the bad sensor somehow (the roomba appears to have more than one way to detect it's stopped moving), and perhaps accept a slightly "dumber" but otherwise working Roomba.