SPAMR: Self-Propelled Amphibious Mine Roller

Row upon row of simple-looking metal capsules are lined up on the deck of a USMC landing craft. One by one, they roll up a ramp and over the side, tumbling into the waves. Sinking to the bottom, each SPAMR rights itself and gets its bearings as its two massive, wraparound wheels propel it across the seabed under command from a central swarm controller. Rolling in formation with its peers to breach a path up the beach, the SPAMR uses its large wheel diameter to power over obstacles, and it's one and a half tons of weight, borne on its metal finned wheels, to trigger and detonate pressure fuzed mines lying in the seabed sand and muck. The 2-wheeled SPAMR represents a novel approach to past surfzone crawling MCM robots and addresses drawbacks to the 4-wheeled skid-steered and tracked models that are most common in this application. Two-wheeled balance robots were originally introduced to the market with the Segway personal transport device in 2001. They possess two characteristics that give them an edge over other architectures. First, mechanical simplicity: the two-wheeled balancing robot has only two moving parts: the drive wheels. This is the simplest mechanism for a fully mobile robot, and this simplicity has added benefits in the marine environment, reducing the number of seals and potential leak areas. Second: mechanical stability without a suspension system: two-wheeled robots offer enhanced stability over rough terrain, without the requirement for suspension. Numerous research papers have confirmed the ability of these robots to tackle terrain more effectively than three and four-wheeled robots. For the CRAB mission, the two-wheeled robot also has the additional advantage that the system's entire weight is distributed over two points of contact, maximizing the surface pressure the robot can apply relative to its total weight. In addition to the advantages conferred by the two-wheeled design, SPAMR’s architecture allows it to contain a variable buoyancy system that will allow it to roll along the bottom, to propel itself up and over large or otherwise unpassable obstacles, and to paddle on the surface like a boat. A breaching formation of SPAMRs will cost less to acquire and maintain than the M1150 Assault Breaching Vehicle, able to tackle difficult surfzone terrain, and will not put any lives at risk as it clears the beach. We believe SPAMR to be a viable approach to fulfill the CRAB mission CONOPs, exceeding mobility, cost and logistical requirements. We also believe it to be superior at meeting these requirements relative to past robotic concepts, and our physical testing conducted in Phase 1 supports this conclusion.