The Pentagon’s robo-blob has grown up a lot these past two years. Now, the thing’s got six legs and some seriously creepy crawling abilities.

In 2008, iRobot, the company behind household vacuum ‘bot “Roomba” teamed up with the Pentagon’s far-out research arm, Darpa, for a new program called “ChemBots.” The idea was to create a team of ‘bots whose movements were inspired by the locomotive talents of “mice, octopi and insects,” allowing them to slide under doors, squeeze into tight spaces or maneuver other tough-to-navigate terrain.

Already, Darpa-funded researchers have made remarkable...