Robust controllability for a class of uncertain linear time-invariant MIMO systems

This note studies the problem of robust controllability of linear time invariant multiple-input-multiple-output systems with A being or A and B both being sign-invariant interval matrices. For controllability, sufficient conditions as well as necessary and sufficient conditions based on interval division method are presented. The note also provides a way to handle interval systems that are not sign-invariant in the A matrix. Some examples illustrate the results.