  This work proposes a novel 2-D formation control scheme for acyclic
triangulated directed graphs (a class of minimally acyclic persistent graphs)
based on bipolar coordinates with (almost) global convergence to the desired
shape. Prescribed performance control is employed to devise a decentralized
control law that avoids singularities and introduces robustness against
external disturbances while ensuring predefined transient and steady-state
performance for the closed-loop system. Furthermore, it is shown that the
proposed formation control scheme can handle formation maneuvering, scaling,
and orientation specifications simultaneously. Additionally, the proposed
control law is implementable in agents' arbitrarily oriented local coordinate
frames using only low-cost onboard vision sensors, which are favorable for
practical applications. Finally, a formation maneuvering simulation study
verifies the proposed approach.
