This robot is a Big Dog

From the Web site of Boston Dynamics:

This robot was the talk of a science-writers' listserv today. See a video of it in action here:

People describing its movement used words like "eerie" and "creepy." I had the same reaction. Why is that? Is it because the motion of those legs looks too human, or not human enough?

Big Dog is quite graceful, particularly in one part of the video where it picks its way across a rock field. The company's Web site refers to the robot as "the alpha male of the Boston Dynamics family of robots." I guess it wouldn't do to describe a buff, tough robot as "graceful."