An unmanned probe is a deployable probe that can conduct archaeological research and collect data on its own. One such probe appears in Metroid Prime: Federation Force.
In M12: Last Stand, an unmanned probe is deployed to a stretch of land on Bion that was a vibrant settlement of the ancient Bion race before it was destroyed by a volcanic eruption. In order to learn more about the ancient race, the Galactic Federation has the probe complete a scan of the buried city. However, the probe comes under threat from an advancing Rohkor Beetle, that could very well destroy or severely damage the probe, which would cause a massive loss of valuable data and research. The Federation Force is immediately assigned to kill the Beetle. The Beetle must be destroyed before it reaches the probe, which will result in a Mission Failure. The HUD will warn the Force every 100 feet the Beetle gets toward the probe.
While the probe is unmanned, in the mission a lobbing turret is found in front of it, which can be used against the Beetle. This suggests that unmanned probes are equipped with defense systems in case of emergencies. Once the Beetle is destroyed, the probe is able to complete its scan. The scan indicates that the buried city's buildings were small, which would not make sense considering the ancient race's massive size. The Federation concludes that they must have increased their size somehow.