The US Marine Corps is working on a prototype disposable robot designed to clear mines from the surf zones of beaches. The Crawling Remotely Operated Amphibious Breacher (CRAB) is a submersible machine that can operate by remote control or autonomously while using a mine flail, tiller, and rake to detonate or remove explosives or man-made submerged obstacles.

If you look at old newsreels of the D-Day invasion of Normandy in 1944, you'll notice it involved thousands of Allied infantrymen running across hundreds of yards of beach sand as they dodged German gunfire in search of cover. This was because the Allies had to land on the five beaches at low tide due to the tank traps, barbed wire, and minefields that the Germans had installed to deter an amphibious assault, and these had to be removed before armor and supply trucks could be brought in.

Seventy-five years later, the US Marines and other amphibious forces still face these and even more sophisticated obstacles. Currently, the Marines use an M1A1 tank chassis with a full-width mine plow called the Assault Breacher Vehicle, and Mine Clearing Line Charges to deal with these. The problem is that the Assault Breacher needs a crew and existing systems cannot handle the turbulent surf zone.

To put fewer lives in danger while removing obstacles out to the surf zone, CRAB is an expendable robotic mine clearer that will work under the Expeditionary Advanced Base Operations (EABO) concept of employing mobile, relatively low-cost capabilities in temporary forward locations. It can be dropped from a littoral utility craft, then crawl on the seabed under its own power to seek out and clear mines and obstacles. If it's destroyed, then only machinery is lost.

"The CRAB will support combat engineers and explosive ordnance disposal Marines by providing a remote or autonomous explosive and nonexplosive obstacle reduction capability within the very shallow water, surf zone, and the beach,” says Michael Poe, team lead for Marine Corps Systems Command’s Mobility and Counter Mobility program. "It will enable the Marine Corps to provide assured littoral mobility to the Naval Force in support of EABO."

The MCSC has submitted a proposal to the US Navy Office of Naval Research to secure funding for a two-year program to develop a CRAB prototype, beginning with writing the system's requirements.

"The CRAB system is important because, currently, the Naval Force can only breach in the surf zone with significant risk to mission or personnel,” says Captain Anthony Molnar, Marine Corps Systems Command’s MK154 and MK155 project officer. "This would alleviate that by having an inexpensive and expendable piece of equipment going through there."

Source: US Navy