When looking at the success of robotics, there's probably no better instance of success than in manufacturing and the military. The adoption of unmanned aerial vehicles (UAVs) by the military is by no means a fad, and could be just the beginning of an autonomous arms race.

The current foray of defense robotics includes robots ranging from underwater submersibles, bomb disposal  units, UAVs, and many more. Although there's still plenty of opportunity in the long term, further defense budget cuts make this segment of robotics especially  risky for investors at the moment. In this special Motley Fool video series below, analyst Blake Bos discusses the challenges facing four companies in defense robotics, and picks the one company he feels safest investing in today.