Robots trying out to become part of the U.S. Army’s battlefield force now have their own real-world testbed built atop what used to be a nerve gas testing site. The Army Research Laboratory has built the Robotics Research Collaboration Campus, or R2C2, in Graces Quarters at the Aberdeen Proving Ground in Maryland. Formerly a superfund site, the area now is sprouting buildings amid mixed wooded and grassy terrain typical of what the Army may find on future battlefields.