Over at the Department of Defense, they've got lots of robots. Most of them aren't scary and glamorous like the lethal Drones you read about all the time. Perhaps the most useful land-based bot is the Tanglefoot, a short, roving critter that sneaks up on Improvised Explosive Devices, then graciously allows itself to be blown up for its trouble. Then there's the Autonomous Platform Demonstrator (APD) a nimble, 9.3-ton, unmanned ground vehicle that can turn on a dime and accelerate to a top speed of 50mph.

But the next step for the Pentagon is getting these machines to autonomously talk to each other. And so the DoD is working on a Collaborative Unmanned Systems Technology Demonstrator (CUSTD) system, which was discussed at the latest Robotics Rodeo, held at Fort Benning, Georgia. The U.S. Army Tank Automotive Research, Development and Engineering Center (TARDEC) hosted the event.

The holy grail is to get to a capability something like this: Two unmanned aircraft are searching for a target over an area of, say, several square miles or so. One plane notices movement, but the enemy is operating in a dense street situation, difficult for a high-altitude device to analyze, much less attack.

So the flying craft signals the relevant position via GPS coordinates to a cooperating APD on the ground. The unmanned car snakes around streets and buildings in pursuit of the goal. Meanwhile, the two planes keep trading information about the location of the target and sending it to the APD, which returns more detailed data about operations as they come in.

"This system demonstrates not only the collaborative interoperability possible among dissimilar vehicles, but also the numerous sensing technologies that can be included onboard as interchangeable payloads," explained Lora Weiss of the Military Sensing and Analysis Center (SENSIAC) in a blog post.

Judgment day?

All very interesting, but like most civilians our main reference point for these developments is the movies, some of which have been anticipating "interchangeable payload" scenarios for years. The most famous of these is Terminator Salvation, the fourth offering in the Terminator series, which also predicts some of the possible limitations of these gadgets.

As fans of this fictitious saga know, in 2004 the Skynet military system becomes self-conscious, concludes that people pose a threat to its existence, and goes ballistic on the human race in an event known as "Judgment Day." It's been fun and games ever since, with Avatar's Sam Worthington replacing the former governor of California as the cyber-protagonist in the latest edition, and Batman's Christian Bale starring as the Hope of Mankind.

At one point in Salvation, Worthington and a couple of kids he's collected around Los Angeles manage to escape a very large Skynet robot. The Tyrannosaurus-like machine is expert at directing flaming blasts at hapless caravans of people, but not so proficient at following them once they get into fast moving pickup trucks.

That's not an obstacle in this instance, however—the dino-bot just dispatches three sleek motorcycle APDs, which relentlessly pursue our heroes until they can be cornered on a bridge and the adolescents collected for the big Skynet human prisoner camp in San Francisco. Here's an example of interexchangeable payload with a vengeance.

But the movie also illustrates a big downside of this technology—it can be hijacked. Later on in the story, Bale grabs himself a loud, ostentatious boombox, waits for one of the cycle bots to show up, trips it with low hanging wire, and converts it into a vehicle for him to ride to the Skynet base up north.

Therein lies the rub—what's to stop miscreants from appropriating these vehicles, a distinct prospect once they run out of fuel? No doubt the Pentagon has already given this problem some thought.

As for the risk of these devices becoming self-conscious and turning on us, hopefully that problem is a little further down the road.