Our newly developed event-based planning and control theory is applied
to robotic systems. It introduces a suitable action or motion referen
ce variable other than time, but directly related to the desired and m
easurable system output, called event. Here the event is the length of
the path tracked by a robot. It enables the construction of an integr
ated planning and control system where planning becomes a real-time cl
osed-loop process. The path-based integration planning and control sch
eme is exemplified by a single-arm tracking problem. Time and energy o
ptimal motion plans combined with nonlinear feedback control are deriv
ed in closed form. To the best of our knowledge, this closed-form solu
tion was not obtained before. The equivalence of path-based and time-b
ased representations of nonlinear feedback control is shown, and an ov
erall system stability criterion has also been obtained. The applicati
on of event-based integrated planning and control provides the robotic
systems the capability to cope with unexpected and uncertain events i
n real time, without the need for replanning. The theoretical results
are illustrated and verified by experiments. Copyright (C) 1996 Elsevi
er Science Ltd.