US Army Yuma Proving Ground (USAYPG) | 2,647 followers on LinkedIn. Truth in testing. | U.S. Army Yuma Proving Ground manages testing in three different environmental extremes; desert (Yuma Test Center), tropic (Tropic Regions Test Center), and cold (Cold Regions Test Center). The largest test center is the Yuma Test Center located in Yuma, Arizona, at Yuma Proving Ground.