  In the typical multiagent formation tracking problem centered on consensus,
the prevailing assumption in the literature is that the agents' nonlinear
models can be approximated by integrator systems, by their feedback-linearized
equivalents, or by dynamics composed of deterministic linear and nonlinear
terms. The resulting approaches associated with such assumptions, however, are
hardly applicable to general nonlinear systems. To this end, we present
consensus-based control laws for multiagent formation tracking in
finite-dimensional state space, with the agents represented by a more general
class of dynamics: control-affine nonlinear systems. The agents also exchange
information via a leader-follower communication topology modeled as an
undirected and connected graph with a single leader node. By leveraging
standard tools from algebraic graph theory and Lyapunov analysis, we first
derive a locally asymptotically stabilizing formation tracking law. Next, to
demonstrate the effectiveness of our approach, we present results from
numerical simulations of an example in robotics. These results -- together with
a comparison of the formation errors obtained with our approach and those
realized via an optimization-based method -- further validate our theoretical
propositions.
