Constrained Controllability of Linear Impulse Differential Systems

We consider the following linear impulse differential control system {x¿ = A(t)x ¿x = B<inf>k</inf>x(t<inf>k</inf>) + C<inf>k</inf>u<inf>k</inf> t ¿ t = t<inf>k</inf> where the control sequences {uk} belong to some set of admissible controllers that is restricted either by norm or by range. We then give a necessary and sufficient condition for global null controllability of time-varying systems and some sufficient conditions for global null controllability for time-invariant systems with special structures.