Float like a Cockroach

New robotic catamarans gain unparalleled ocean stability from a bug-like frame.

Tech Advancements Lead to Autonomous, Floating, Bug Bots?

Imagine a vessel steady enough to execute accurate hydrographic surveys in Lake Huron, high tech enough to analyze the ocean’s fish populations and pollution levels and fast enough to chase off intruder vessels and protect Navy ships. Now imagine that vessel shaped like an insect and completely autonomous. Mix all that together and you get the WAM-V.

WAM-V stands for Wave Adaptive Modular Vessel. It’s the brainchild of Ugo Conti, the founder and Chief Technology Officer of Marine Advanced Robotics in Richmond, California. Once a researcher at UC Berkley and, subsequently, the founder of ElectroMagnetic Instruments, Conti quit his job to sail the world with his wife, Isabella, and four-year-old son Maurice, for three and a half years. But he soon found how terribly seasick he became.

“There’s got to be another way,” Conti thought to himself as he mustered the will to keep his stomach from turning.

“Being motion sensitive, my engineering mind was desperate to invent a better way to sail the waves,” he said. “My motion sensitivity was annoying especially at the beginning of the trip, obviously due to fear.”

Conti has been long fascinated by insects—particularly cockroaches. He realized the way that these animals move might hold a key to ocean stability. As cockroaches run, they use what is known as an alternating tripodal gait, where two outer legs on one side of the body and the middle leg on the other are in contact with the ground at the same time, producing good stability and reasonable speed.

When the same principle is applied to the WAM-V engineered catamaran in the ocean, it means when a wave hits, each hull moves independently and naturally, reducing motion by up to 70 percent.

With the cockroach as his inspiration, Conti first developed a catamaran called the Proteus. The boat featured a 50-foot gap between its inflated hulls. Those hulls bore hinged motor pods at each end, and were connected to a bridge and cabin suspended just above the ocean by way of four metal legs atop titanium springs. The design allowed the boat to flex and move with the ocean waves. But, as innovative as the design was, it lacked something.

“That idea was faulty because sometimes the motion was reduced, but when all the phases of the oscillations were added, the motion of the upper structure exceeded what the motion of a rigid boat would have been,” Conti explains.

The good news about the Proteus, Conti notes, was that its hinged motor pods ensured that the propellers always stayed in the water. This was a very important feature, because without it, a power catamaran with a length-to-width ratio of 2:1 could lose propulsion in rough seas—often on one side as one propeller lifted from the water. The subsequent loss of steering and control could have dire consequences especially in the face of oncoming waves. In the conditions when propeller contact was needed most, Conti’s system worked flawlessly.

Replicating the desirable qualities of the Proteus and reconfiguring what was lacking, Conti came up with the new generation of WAM-V’s. This second-generation model features a partially rigid, partially flexible hull to prevent overall flexing, leaving the bow section free to bend and absorb wave impacts while driving upwind. There are also only a forward set of suspension springs, increasing the capability to deal with forward impacts. Overall, the WAM-V’s articulated structure is completely free to move following the ocean’s surface; in contrast, on Proteus there were still resistances, with only semi-absorption by the suspensions, ultimately causing deleterious repetitive stresses.

So, what can the newest WAM-V actually do as result? A lot—according to the second generation WAM-V co-designer, Mark Gundersen.

“It’s excellent for doing things like hydrography, launching and recovering of aerial and underwater vehicles, putting sensors in the water—and not only from an efficiency standpoint, but its very lightweight structure also allows for degrees of freedom otherwise unattainable,” Gundersen says. “It can move with very little energy, utilizes renewable energy whenever possible and its modularity means it can be taken apart with ease. I mean, you could take our 16-foot model apart, box it up and air freight it anywhere in the world in a very short amount of time.” The 8-foot model can even be broken down and checked as baggage on a domestic airline.

The WAM-V currently comes in three sizes: 8, 16, and 22 feet. What makes the vessel particularly efficient, besides its stability, is that it’s fully autonomous. Using mobile or satellite communication, the robotic catamaran can be programmed to reach specific coordinates and handle a variety of retrieval, release and other technical tasks, within or outside of the operator’s view. Should you need to abort your mission, the vessel provides a constant live camera feed and can be redirected with new commands at any given moment.

Among the biggest uses for the WAM-V are hydrographic surveys owing to the vessel’s unparalleled stability, but some of their more interesting uses include naval patrol and recording footage for coastal views (from the water POV) of streets and highways on Google Maps. And while you won’t be seeing mass produced crewed versions anytime soon, Gundersen is hopeful that the WAM-V could be put to recreational use in the future.

“I live in Alameda, in the Bay area, and my vision is to have a 22 [that can] carry people, maybe with a cockpit so you can get in it and sit back,” Gundersen said. “So, you can blend the autonomous function with the ability to drive [the boat] when you want to.”

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This article originally appeared in the January 2023 issue of Power & Motoryacht magazine.

Source: https://www.powerandmotoryacht.com/at-sea/tech-advancements-lead-to-autonomous-floating-bug-bots