With much discussion, interest and doctrine now enshrined for unmanned systems in the air domain -- and, perhaps to a lesser extent, in the sea and undersea domains -- unmanned ground systems are much harder to perfect than their air and sea counterparts.

There are significantly more objects on the ground for unmanned systems to avoid than in the air or the sea, making operations inherently difficult. Despite these challenges, the military is pressing forward in developing concepts for unmanned ground vehicles.

"Our main work in ground vehicles is quite exciting," William Roper, director of the secretive Strategic Capabilities Office, said at CSIS July 13. The Strategic Capabilities Office, or SCO, works to protoype and test solutions to be adapted rapidly using existing systems or technologies.

Roper said that this year his office has sought to increase its work with the Army. Part of this work centers on channeling and utilizing existing advancements in commercial driverless vehicles. "We've taken a very hard look with the Army on what's the mission impact if we use commercial-style unmanned ground vehicles. Given that they're not going to go off road, but do we get a good enough solution to get moving...to me, [good enough] usually means it's good enough to get started because I see the improvement pipeline behind it."

However, according to others in the military space, unmanned ground vehicles could still be far off be given the complexities and obstacles that exist in this domain. While commercial driverless cars were developed on predictable, mapped, paved roads, in military use "not only will we stay on roads, but when the roads become more dangerous we'll go off road," Deputy Defense Secretary Robert Work said at a Washington Post-hosted event in March.  "That type of navigation is extremely difficult."

For Roper, his hope is "that we will find a sweet spot for saying let's go out and start working with existing technology that when future technologies allow us to go off road mature, we'll already have experience in the pipeline."

There are myriad uses for unmanned ground vehicles, said Paul Scharre, senior fellow and director of the 20YY Future of Warfare Initiative at the Center for a New American Security, such as driverless vehicles for convoys (which have already been used), vehicles that can accompany dismounted soldiers or even unmanned vehicles that can serve as scouts to look for enemy positions, allowing for greater risk than a commander might take with a manned element.

With these systems, however, it's all about the level of autonomy, Scharre told C4ISRNET.  This distinction exists between remotely controlled vehicles and those that are fully autonomous, which are not binary but rather are somewhere in the middle. For example, a vehicle could follow along in a convoy operating under existing levels of robotics, such as cruise control or autopilot, with an operator in the cabin to take control if need be. This would free up the soldier to pay greater attention to what's ahead such as threats or improvised explosive devices, as well as reduce accidents.

Additionally, fully autonomous systems, Scharre noted, won't be plausible because if a system gets stuck or runs into a situation where it needs help and calls back, a user must be allowed to remotely operate it.

The scout capabilities are probably more near-term than systems that will operate alongside soldiers given all the complexities involved in systems being able to understand where humans are in relation to the vehicle, he added.

Taking advantage of technologies that already exist in the commercial space regarding driverless cars can help accelerate integration and understanding for the Army and Marines to ensure they have personnel that are "trained to use it and know how to analyze the impact, they've thought through what missions they can do," Roper said.

Going forward, Scharre said he sees a lot of potential, especially surrounding advancements in object recognition and deep neural networks in which researchers have been able to build neural networks to exceed some human abilities. They networks aren't functional in all environments such as rain or snow, but the advancements are impressive.

Scharre conceded that Russia is building a large volume of unmanned ground systems that include golf cart-sized vehicles and tanks. Moreover, Russia is arming many of its systems, something he said the U.S. has been hesitant to do. Russia is more aggressive in operational concepts and building prototypes, especially of the weaponized variety, he added.

Roper stated that he will be reporting back to Army leadership as to what his office found in unmanned ground systems.