Here we see MARLO, a robot, walking at the University of Michigan.

First he walks inside, then he moves outside, though still supported by a safety harness and trailing batteries.

The robot is a creation of engineering professor Jessy Grizzle at the University of Michigan and his colleagues, who have been making steady progress on walking robots for nearly a decade.

MARLO is the third-generation bipedal robot of this type. The first was a Franco-German walking bot named Rabbit, which was retired in 2005. It reminds me of the bottom of a satyr.

The second was named MABEL. MABEL could run at a nine-minute mile pace, but only on a circular track.

And now we have MARLO, which is the first of these walking bots to attempt to move in 3D space, without being attached to lateral support.

It's not an easy task: Just ask any toddler.

MARLO's video debuted on a day when the New York Times' John Markoff revealed that Google has quietly purchased seven robotics companies in their own efforts to reinvent the humanoid robot.

Among the companies are Schaft, a small team of Japanese roboticists who recently left Tokyo University to develop a humanoid robot, and Industrial Perception, a start-up here that has developed computer vision systems and robot arms for loading and unloading trucks. Also acquired were Meka and Redwood Robotics, makers of humanoid robots and robot arms in San Francisco, and Bot & Dolly, a maker of robotic camera systems that were recently used to create special effects in the movie “Gravity.” A related firm, Autofuss, which focuses on advertising and design, and Holomni, a small design firm that makes high-tech wheels, were acquired as well.

The effort is being led by Andy Rubin, a former robotocist who led the Android team.

Humanoid robots have been an area of fascination for researchers since long before we could actually build them. And even though few people use or encounter bots like Honda's ASIMO or MARLO, we've come a long way since Westinghouse's animatronic ELEKTRO "motoman" from the 1937 World's Fair.