A 60 Mph Unmanned Tank

The Ripsaw:

"Every engineer they consulted said they couldn’t best the 42mph top speed of an M1A Abrams, the most powerful tank in the world. Other tanks are built to protect the people inside, with frames made of heavy armored-steel plates. Designed for rugged unmanned missions, the Ripsaw just needed to go fast, so the brothers started trimming weight. First they built a frame of welded steel tubes, like the ones used by Nascar, that provides 50 percent more strength at half the weight."