It's not a "robot" it's a remote controlled cart with a bomb in it, completely operated by a human being. If it makes cops feel safer, it means they're less likely to use lethal force inappropriately.
I, for one, welcome our new bomb-cart overlords.
The problem is that police already had bombs in their arsenal. Invoiced, ordered, shipped, accepted, catalogued, stored, paid with tax dollars, and waiting to use on citizens. THAT is the problem!!