Updated 9/6/12 8:41 am

Robots are already stronger than humans, able to lift thousands of pounds at a time. In many ways, they're smarter than people, too; machines can perform millions of calculations per second, and even beat us at chess. But we could at least take solace in the fact that we could still outrun our brawny, genius robot overlords if we needed to.

Until now, that is. A four-legged robot, funded by the Pentagon, has just run 28.3 miles per hour. That's faster than the fastest man's fastest time ever. Oh well, ruling the planet was fun while it lasted.

The world record for the 100 meter dash was set in 2009 by sprinter Usain Bolt, who averaged 23.35 mph during his run for a time of 9.58 seconds. Over one 20-meter stretch, he managed to get up to 27.78 mph. It was a pretty impressive feat.

The Cheetah – a quadrupedal machine built by master roboteers Boston Dynamics and backed by Darpa, the Defense Department's far-out research division – not only topped Bolt's record-setting time. It also beat its previous top speed of 18 mph, set just a half-year ago.

"To be fair, keep in mind that the Cheetah robot runs on a treadmill without wind drag and has an off-board power supply that it does not carry," a Boston Dynamics press release reminds us. "So Bolt is still the superior athlete."

But the company is looking to change all that, and soon.

In recent months, the Cheetah team "increased the amount of power available to the robot. More power means faster motion and more margin in the actuators for better control," Boston Dynamics CEO Marc Raibert tells Danger Room in an email. The robot-makers have also been "working on the control system, refining how the coordination of legs and back works and developing a better understanding of the dynamics.

He adds, "You can see that there is still room for improvement at the end of the video we just posted, where the robot starts to go faster, but loses control and trips."

But those control systems are improving. The next major step is to build an untethered version – one with an onboard engine and operator controls that work in 3D.

"Our real goal is to create a robot that moves freely outdoors while it runs fast. We are building an outdoor version that we call WildCat, that should be ready for testing early next year," Dr. Alfred Rizzi, the technical lead for the Cheetah effort, says in a statement.

It may sound a little outlandish. But keep in mind: Boston Dynamics has done this before. Its alarmingly like-like BigDog quadruped is able to tramp across ice, snow, and hills – all without the off-board hydraulic pump and boom-like device now used to keep the Cheetah on track. An improved version of the BigDog can haul 400 pounds for up to 20 miles. (See what we mean about robot brawn?) The company also has a biped 'bot, Petman, that looks like a mechanical human – minus the head.

The idea behind these biologically-inspired robots is that legs can carry machines across terrain that would leave wheels or tracks stuck. To be a true partner to a human soldier, a robot has to walk like one, too. Darpa says Cheetah and company will "contribute to emergency response, humanitarian assistance and other defense missions." But when the robot was first introduced, Boston Dynamics noted that its flexible spine would help it "zigzag to chase and evade."

As if being brilliant and super-strong wasn't unnerving enough.