  Self-organization and control around flocks and mills is studied for
second-order swarming systems involving self-propulsion and potential terms. It
is shown that through the action of constrained control, is it possible to
control any initial configuration to a flock or a mill. The proof builds on an
appropriate combination of several arguments: LaSalle invariance principle and
Lyapunov-like decreasing functionals, control linearization techniques, and
quasi-static deformations. A stability analysis of the second-order system
guides the design of feedback laws for the stabilization to flock and mills,
which are also assessed computationally.
