A select few US tanks will soon be running an automated defence system that you might charitably describe as something resembling a forcefield, being as it's a proximity based tracking and blasting system that wipes out any incoming grenades troubling its airspace with a pre-emptive shot of its own.
It's a technique known as the Trophy Active Protection System developed by an Israeli firm that's been chosen to protect its rolling war machines, with some of the US military's M1 Abrams tanks and their Stryker armored vehicles to be outfitted with the active defence tools.
Systems like Trophy have been in development for years, hence this creaky old trailer, first uploaded in 2006:
It's a little cruder than the trailer suggests. It's shotguns paired with a radar. That's it, but it works. Another test from 2014 shows it working for real in a military exercise, with Lt. Gen. Robert Walsh telling a US military subcommittee that: "We’ve got to start thinking more with a higher technology capability, with vehicle protective systems, active protective systems that can defeat anti-tank guided munitions, RPGs... along with soft capability, which is the technology our aircraft have." [USNI via Jalopnik]