It only takes a brief glance at the world news to realise why the use of unmanned vehicles for logistical and surveillance purposes in combat or peace keeping situations is now considered of paramount importance by the military. By removing soldiers from these exposed positions, their lives can be safe guarded from road side attacks and other forms of insurgency. And, no matter what your views are on the wars/peace keeping missions that our military are undertaking, ensuring that fewer men and women will lose their lives can only be a good thing.
However, until recently research into such areas had been predominantly based on road marking recognition and semi-autonomous vehicles, i.e. partly remotely controlled, neither of which is ideal in the middle of a desert or rain forest. What the military need is a vehicle that can traverse any environment, whether on or off-road, completely without intervention from humans. Therefore the US military came up with the idea of the first DARPA Grand Challenge, which took place in 2004.
Just as with the ongoing X Prize competition, the Grand Challenge was seen as a way of leveraging not just the ingenuity and skills of the American military but also that of the whole world. So long as each team had at least one member that holds US citizenship, they could participate. The aim was to accelerate conception, research, and eventually proof of concept of fully computer controlled ground vehicles, the technology from which could then be integrated into eventual unmanned military vehicles.
The premise of the first challenge was quite simple; build a fully autonomous ground vehicle that could traverse a set course that ran 150 miles across the Mojave Desert from Barstow, California to Primm, Nevada without any human intervention. A time limit of 10 hours was given and it was a straight time trial race for the first prize of one million Dollars. However, if no cars completed the course in time, or at all, the prize would go unclaimed, which of course is precisely what happened. Indeed the furthest any of the cars got was 7.4 miles into the course, which was achieved by Carnegie Mellon University's Red Team.
Unperturbed, DARPA organised a second Grand Challenge a year later, and this time the teams were a lot more successful. In total, five teams completed the course within the time limit and all but one of the 23 finalists surpassed the 7.4 mile distance achieved by the best vehicle in the 2004 race. The overall winner and recipient of the one million Dollar first prize was a team from Stanford University with its car "Stanley" that was based on a Volkswagen Touareg.
Now that the ability of unmanned vehicles to traverse unmarked terrain had been proven, the next step in the move towards creating safe and useable unmanned vehicles was to prove that computers could obey the rules of the road. So, the DARPA Urban Challenge was born.