On some controllability aspects of discrete-time systems by matrix generalized inverse
Nazar Al-Nasr · International Journal of Systems Science · 1984
The simplest matrix generalized inverse is used to obtain some necessary and sufficient conditions for state and output controllability or servomechanism controllability of linear time-invariant discrete systems. The nulling-output problem as a very special case of output controllability in the servomechanism sense gives rise to different controllability spaces (Molinari 1976 a, b) that can be explicitly described with the aid of a {l}-inverse of a matrix. In relation to the nulling-output problem, a method of finding zeros and zero directions for discrete systems is also presented.