Just FYI - the iRobot Roombas DO indeed vacuum, not just sweep.
There is a small vacuum motor in the rear of the dust bin, that exhausts air
outside, through a cleanable filter.

There was some speculation that they only were carpet sweepers. Incorrect,
they have suction, and after a few months with mine - I'd say they work
pretty well.

-W (just bought a second one to reduce the workload on the 1st one)

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