The American soldier may soon have a personal combat-ready sidekick that will fetch him essentials such as water, ammo and medicine and provide extra firepower when he’s under attack. It’s a robotic servant dubbed BirdDog that’s in the works by the U.S. Navy and the private research firm Science Applications International Corporation. BirdDog is designed to complement the military’s future fleet of unmanned vehicles, which are expected to account for one third of all ground combat vehicles by 2015.