Matched asymptotics for a spherical low-Reynolds-number treadmilling swimmer near a rigid wall

The evolution equations for a small spherical low-Reynolds-number swimmer actuated by means of an imposed treadmilling action on its surface are derived by means of an asymptotic analysis. The analysis rests on the assumption that the swimmer radius is small compared with its distance from the wall. It generalizes, to the more realistic 3D case, recent work on 2D treadmilling swimmers near a no-slip wall. The study is motivated by a recent work on the dynamics of Volvox algae near solid surfaces.