M109 howitzer

Developed by the U.S. Army, the M109 Paladin is a series of self-propelled 155mm howitzers used by the U.S. and many other nations. The latest version in U.S. service is the M109A6, although a M109A6-PIM is a redesigned version. The evolutionary direction of M109 systems is to make them more and more networked into a common battlefield information system, yet be able to act autonomously. One strong trend, given the real-world ability of a sophisticated enemy to track the trajectory of a shell back to the weapon that fired it, is to be able to "scoot-shoot-scoot": arrive at a location and quickly calculate a trajectory to the target, fire at that target, and then immediately move to a new location before counterfire can strike.