Following the route of Smoluchowski we continue the study of single active Brownian particles by investigations of the motion of pairs. After studying free motion we consider the relative motion of bound pairs. We study the attractor structure in a space of five dynamical variables. In particular we investigate the translational motion and analyze the bifurcations between the translational and the rotational modes of the pairs. The influence of noise is studied. Finally, we investigate extensions to the dynamics of N-particle swarms with harmonic interactions.

PACS numbers: 05.40.Jc, 05.45.--a