What are mobile dolls?

The mobile dolls seen in Gundam Wing are
computer-controlled mobile suits which do not require a
human pilot. Though they rely on human commanders to tell
them which enemy units to attack, mobile dolls are otherwise
fully capable of maneuvering, fighting, and executing
missions without human guidance. The first production model,
the OZ-12SMS Taurus, can also be operated by a human pilot,
but the later OZ-02MD Virgo doesn't even have a cockpit.

Though the term itself is used only in Gundam Wing's After
Colony world, machines similar to mobile dolls appear in
other series as well. The RX-78 Gundam of the original
series was equipped with a sophisticated computer which
learned from its pilot's actions, and ultimately proved
capable of fighting on its own. And in G-Saviour and Turn A
Gundam, we see unmanned mobile suits which function much
like Gundam Wing's mobile dolls.