  Most approaches for self-triggered control (STC) of nonlinear networked
control systems (NCS) require measurements of the full system state to
determine transmission times. However, for most control systems only a lower
dimensional output is available. To bridge this gap, we present in this paper
an output-feedback STC approach for nonlinear NCS. An asymptotically stable
observer is used to reconstruct the plant state and transmission times are
determined based on the observer state. The approach employs hybrid Lyapunov
functions and a dynamic variable to encode past state information and to
maximize the time between transmissions. It is non-conservative in the sense
that the assumptions on plant and controller are the same as for dynamic STC
based on hybrid Lyapunov functions with full state measurements and any
asymptotically stabilizing observer can be used. We conclude that the proposed
STC approach guarantees asymptotic stability of the origin for the closed-loop
system.
