  This paper investigates the impact of bounded actuation on the
connectivity-preserving consensus of two classes of multi-agent systems, with
kinematic agents and with Euler- Lagrange agents. The investigation establishes
that: (1) there exists a class of gradient-based controls which drive kinematic
multi-agent systems to connectivity-preserving consensus even if they saturate;
(2) actuator saturation restricts the initial states from which Euler-Lagrange
multi-agent systems can be synchronized while preserving their local
connectivity; (3) Euler-Lagrange multi-agent systems with unbounded actuation
can achieve connectivity-preserving consensus without velocity measurements or
exact system dynamics; and (4) a proposed indirect coupling control strategy
drives Euler-Lagrange multi-agent systems with limited actuation and starting
from rest to connectivitypreserving consensus without requiring velocity
measurements and including in the presence of uncertain dynamics and
timevarying delays.
