At the crack of dawn this Saturday, a 200-mile race across the Mojave Desert begins. The competitors are robotic vehicles taking on the form of SUVs, dune buggies and golf carts. It’s the DARPA Grand Challenge, a contest designed by the Pentagon and its Defense Advanced Research Projects Agency to spur advancements in the field of robotics. The race is open to all-comers, so the government is hoping the $1 million prize will encourage university teams and garage scientists alike to come up with designs that may some day save lives on the battlefield.