  With the increasing ubiquity of networked control systems, various strategies
for sampling constituent subsystems' outputs have emerged. In contrast with
periodic sampling, event-triggered control provides a way to efficiently sample
a subsystem and conserve network resource usage, by triggering an update only
when a state-dependent error threshold is satisfied. Herein we describe a novel
scheme for asynchronous event-triggered measurement and control (ETC) of a
nonlinear plant using sampler subsystems with hybrid dynamics. We extend
existing ETC literature by adopting a more general representation of the
sampler subsystem dynamics that do not require trigger periodicity or
simultaneity, thus accommodating different sampling schemes for both
synchronous and asynchronous ETC applications. We ensure that the plant and
controller trigger rules are not susceptible to Zeno behavior by employing
auxiliary timer variables in conjunction with state-dependent error thresholds.
We conclude with a numerical example in order to illustrate important practical
considerations when applying such schemes.
