A long pursuit of kayak pedal power

Photo and Text

By TOM WATSON

In the evolution of propelled watercraft over several millennia, mankind’s propulsion mechanisms have advanced from outstretched palm to pole to paddle to sail and, finally, beginning in the late 1790s, Robert Fulton (of steam engine fame) experimented with a ship powered by a 4-bladed propeller.

Jump ahead two centuries, and propulsion mechanisms for kayaks were just getting off the ground. Most recently, in the past 20 years, kayaks have added new propulsion systems and pedal-drive mechanisms to their traditional and historic reliance on hand-powered paddles only.

Basically there are two types of pedal-driven kayaks. One is a push/pedal mechanism which requires that pedals are pushed down in an alternating motion to transfer force to a propeller mounted beneath the kayak. The other is a rotational pedal mechanism like a bicycle where force is applied to pedals in constant rotation to provide power to a propeller below.

Robotic Tuna

Developmentally, some ideas were quite unconventional.

“We were working with a robotic tuna,” recalls Jim Czarnowski, who while working on his master’s degree at MIT in 1997 was engaged in research for a fin propulsion system for watercraft.

“We had cast its structure using the body of a real fish,” he said. “The robot swam like an actual tuna while tethered and connected to sensors that could measure thrust. Those findings showed that a back-and-forth motion was more powerful than a propeller.”

Czarnowski’s team ultimately looked to the way a penguin moves through the water. The bird doesn’t move its body, only its flippers, producing both speed and power.

Not Just A Mirage

At the same time, West Coast sailing enthusiast Greg Ketterman was exploring the concept of putting a sail upside down under the boat. Ten years later, both he and Czarnowski were on the Hobie team securing a patent for “…the means of propelling a vessel and more specifically [as] it relates to the design of a thrust-producing oscillating fin,” thus an Oscillating Foil Propulsion System, and the first step towards HOBIE’s Mirage Drive.

Hobie’s system relies on foot pedals providing propulsion below the boat.

Andy Zimmerman, who co-founded Wilderness Systems in 1986, remembers it. “There were many backyard one-off’ers creating contraptions using propeller drives, but none that were really commercially viable,” he said.

Most all of these home-built