Despite sophisticated technology – navigation software, stair detection, cameras to detect dirt – robot vacuum cleaners (like IROBOT BRAAVA 380T ) are still comparatively poor at removing dirt from carpet.
Robot vacuums can't generate the suction of a standard vacuum and while they can leave the carpet looking clean, below the surface a lot of dirt is left behind. Over time, this can damage the pile.
For most homes, we can't recommend any robot vacuum as a replacement for your trusty drag-around vacuum.
In our tests, we've found robot vacs can pick up a reasonable amount of fluff (such as pet hair) along with some dirt, but also seem to push the remaining dirt even deeper into the carpet pile.
Most of the models we've tested are very good at cleaning hard floors – albeit not always in the corners and edges.
For a house with mostly hard floors, most of the tested robot vacuum cleaners will do a reasonable job of keeping the floors clean when run on a daily basis, though a more thorough cleaning with a standard vacuum (or a broom) will still be needed occasionally.
In a home with carpeted floors, a robot vac is fine for a purely cosmetic tidy-up, but the carpet will need a regular going-over with a standard vac to get most of the actual dirt out.