Inchworm motion of a two-headed motor
= Inchworm motion of a two-headed motor
In inchworm <motion> the same head remains in front as the two heads advance without exchanging order. Ideal fixed label <positions> then advance by one centre-of-<mass> step per cycle, contrasting with the unequal alternating <displacements> possible in <hand-over-hand motion of a two-headed motor>.