August 5, 2011: The U.S. Army has canceled all versions of its MULE (Multifunction Utility/Logistics and Equipment) robotic vehicle. Last year, it cancelled the transport and mine clearing versions. Now the remaining version (Armed Robotic Vehicle-Assault Light) has been cancelled, and the development work on MULE is dead.

MULE was a UGV (unmanned ground vehicle) that was part of the (now cancelled) FCS (Future Combat Systems) program. While maligned by the media, many politicians, and even people in the army, as an expensive boondoggle, FCS provided the money to create some revolutionary, and effective, combat equipment. MULE was one of these futuristic concepts, a robotic vehicle for carrying stuff on the battlefield. In practice, it did not work out. Close, but not close enough.

MULE is a one ton, six wheeled vehicle that is 4.8 meters (15 feet) long, 1.93 meters (six feet) wide, and carries nearly a ton of equipment or weapons. The operator (any infantryman with an hour or so of training) uses a handheld controller to tell the MULE to go from Point A to Point B. The MULE has enough computing power to get over obstacles it can handle, and go around those it can't.

The MULE was to be used to do a lot of dangerous jobs normally handled by the troops. Like bringing supplies (ammo, water, weapons or medical supplies) that last few hundred meters, to where the fighting is going on. Currently, that means troops hauling this stuff themselves, and exposing themselves to enemy fire. The MULE can also take casualties far enough away so a medevac helicopter can take over. MULE can also be equipped with mine clearing equipment, to perform another dangerous job. MULE was also to be equipped with heavy weapons (.50 caliber machine-gun, small cannon or missiles), that would be fired under human control.

The troops were eager to have something like the MULE around, if only because it makes their life in the combat zone so much easier and safer. The MULE was designed to take a lot of damage and keep going, but only actually using it in combat would reveal what its weaknesses were, and what modifications had to be made. Field tests were disappointing. So MULE was cancelled. Development continued, but not enough progress was made. So the troops will have to wait for Son of MULE, which will show up eventually. Work is continuing on similar projects.

It was only six years ago that the army put UGV development into high gear, in an attempt to get more UGVs (unmanned ground vehicles) into the hands of the troops. Over the last few years, thousands of small UGVs have been used by American troops for checking out caves and buildings. Some of these lightweight (under a 45 kg /100 pounds) robots were even equipped with weapons, but not used much when armed.

The army hoped that the next class of UGVs would be heavier, weighing 1-3 tons. That's where the much anticipated MULE came in. As more gadgets are invented for the troops, the weight they have to carry keeps increasing. One solution was believed to be a UGV that can accompany troops, carrying a lot of this load (otherwise, each soldier is going to be carrying about 45 kg/100 pounds of gear, which is hardly “fighting weight.”) There’s one problem, a major one, and that was building of a sensor/software system that would allow the mule UGV to move along the ground without a human driver. This proved to be a major obstacle. It is possible to have a remote human operator control a UGV. That keeps people out of harm’s way, and the military is using operators half way around the world to operate UAVs. This "reachback" technique is possible because of cheaper and more abundant satellite communications. No reason it could not be done for UGVs. And this may be the interim solution until a smart enough UGV navigation system is built. This would be a big help for the troops, as they would have the benefit of these UGV drivers, but these operators (they could even be civilians), would be out of harms' way, and would not consume supplies in the combat zone.

The FCS plan was that, once the mules were with the troops and working well, armed mules, some of them armored and weighing up to ten tons, would show up. Without a human crew, a ten ton armored mule would look like a miniature tank, but would be carrying a 25-30mm automatic cannon and 2-4 Javelin missiles. These vehicles would also carry day/night vidcams, thermal imagers, “ears” (acoustic sensors) and a nose (chemical sensors). The combat mules can also talk, using embedded foreign language systems (like the hand held versions troops have been using), or human translators (again, these could be back in the United States, and could even be civilians.) The advantage of these armed mules is that they can destroy enemy armored vehicles, while being harder to detect (as they are about the size of small sports car). The main use of these unmanned tanks would be reconnaissance. No friendly troops are risked when these vehicles are hit, and their sensors and human operators (some of whom are far to the rear) are more alert, over longer periods of time, than human crews in current armored vehicles. But the cancellation of FCS put a halt to development of these larger, armed, UGVs.

Meanwhile, there are already civilian robotic security systems that use UGVs. But their software moves a vehicle around a known course, with limited navigation ability, and only enough smarts to alert a human operator that the droid has encountered something that is not supposed to be there. A combat UGV that will be allowed to decide when and where to fire is possible now. But there is reluctance to build them and turn them loose.

There is a precedent for such robotic weapons. The first such autonomous weapons of this class were the landmines developed in the 1930s, and widely used during World War II. Torpedoes and naval mines are the same type of weapon. But at sea, it’s much easier to keep track of where you are, where you’re going and what the target is. Land warfare is a lot messier, and requires much more “intelligent” software to operate effectively. But it’s not a matter of “if” these autonomous war droids are going to appear, but when. It's possible that the next generation of American combat vehicles will be largely unmanned versions.