Ok this is what I meant in my earlier post. The Homebot camera (indicated in green) is very low and close to the floor. It only scans forward and not upwards.
My coffee table the base is narrower than the top as per my picture. So when the camera scans the front, it sees the part indicated in red in my picture and thinks it can move forward till that red area.
What it doesn't realise is the part indicated in blue is blocking as the camera is unable to see that high. So as the bot moves forward in an attempt to reach the red part, it crashes into the blue part.
Similar problem with my shoe cabinet as the shoe cabinet doors are NOT flushed with the base and sticks out like the blue part in my picture above.
That is the only thing I can think of as it does not crash into my dinner table legs or into the walls.
But having said all that, my kitchen cabinets are also like my shoe cabinet i.e. the doors stick out a bit. Yet the bot doesn't crash into the kitchen cabinet. So I guess its still a mystery after all.
For the record I do use the brush to brush away dust from all cameras. Sometimes I also use my Philips vacuum to suck away dust (if any) from my cameras, and wipe it with my 3M dusting cloth. So its NOT like I don't maintain my bot.