Engineers then had to set about finding a way of imitating and improving on the action of handwashing, so that dirt could be released more quickly and efficiently from the fabric fibres than in an ordinary, single drum machine.

After three months they discovered that two drums, which rotated in opposite directions, performed the improved wash action they were looking for.

Once Dyson engineers had created the Contrarotator's™ fundamental technology, the two drums rotating in opposite directions, they didn't allow themselves to be steered by what the competition was doing.