Engineers with the US Army recently completed tests on a 20-ton unmanned Stryker vehicle, intended to be used as part of a convoy. In the tests, the robot vehicle was able to follow a manned vehicle at speeds averaging 22 miles per hour, topping out at 40 on straightaways. The robotank was also able to detect obstacles laid down by the lead vehicle and maneuver around them. One of the big advantages of the vehicle appears to be the ability to operate without GPS, instead relying on terrain data sent from the lead vehicle and data gathered from on-board sensors; soldiers will remain in the vehicles for now, but in the future, these mech-warriors could be used for tasks like resupplying forces in dangerous environments.