Although the military began developing technology for driverless vehicles in 2003, Mashable recently reported that the project has fallen behind of its 2015 deadline. 

According to the news source, the military originally planned to have one-third of its ground fleet unmanned within the next two years. The specially designed vehicles would be used in high-risk areas to move supplies as a way to protect soldiers from dangerous weapons and explosives. However, a lack of funding has hindered the progress of this advanced technology.

"Autonomous vehicles have come a very long way over the past decade, but the technology still has a long way to go before the U.S. Army and Marine Corps will find it ready for battle," Sam Brannen, a senior fellow at the Center for Strategic and International Studies, told the news outlet. "The money for this transition simply isn't in the budgets."

Although the military – and the civilian sector – is still working on creating safe driverless vehicles, the use of remote-controlled robots has become widespread in combat zones. According to Wired magazine, several civilian companies are currently working on robotic technology equipped with automatic weapons and grenade launchers. These remote-controlled lethal robots would work alongside ground troops in combat.