Blogger Signaltheorist decided to evaluate the efficiency of the Roomba by tracking its movements:
I set up a photo camera in my room, turned out all the lights and took a long-exposure shot of my roomba doing it's thing for about 30 minutes. The result is a picture that shows the path of the roomba through it's cleaning cycle, it looks like a flight map or something. It really hits every spot!
http://signaltheorist.com/?p=91 via J-Walk Blog
This thing is amazing !! The Roomba is not designed to be a precise on-demand cleaning system, it is designed to be a very thorough maintenance bot. If you expect to let it roam once and get the house 100% vacuumed on it’s first try, you will be disappointed – but if you are willing to let it run autonomously 3 to 5 times a week on a programmed schedule while you are at work, it will clean your house more thoroughly than you are ever likely to with a weekly manual vacuuming.
I started by first vacuuming my 1100 square foot ranch house with my Dyson vacuum as usual, and then let Roomba have at it for 2 hours. It came back to its charging station full of dust. I emptied it, let it charge, than ran it again for 2 hours, it came back full of dust again. I decided to keep sending it out until it comes back mostly empty, and it’s on its 11th 2hr vacuuming session over a week period, and it is finally starting to return with minimal dust. The house has that fresh spring clean smell for the first time in years, and is absolutely spotless.
With a battery pack the size of a couple bars of soap, the Roomba can vacuum for 2 hours on a 3 hour charge, which draws significantly less power than a regular vacuum. It is very quiet, and runs completely randomly around the house, vacuuming the same areas over and over again from all possible angles, pushing carpet fibers around and deep cleaning everywhere.
It will go back to a normal programmed schedule of vacuuming the house every weekday starting at 8:00am sharp while I’m at work, and all I need to do is empty the dust bin when I get home :-)