Alternative to boat propellers mimics movement of fish fins

French startup FinX has developed a bio-inspired, electric propulsion system which has the potential to inspire a new generation of propellerless boats

Spotted: FinX is the bio-inspired brainchild of CEO and founder Harold Guillemin and consists of a propulsion system that echoes the movement of fish fins.  

The concept is simple. The FinX thruster is attached to the winding of an electric motor, which is set in motion by the currents, thus creating a wave-like, fin-like effect. For the system to operate, an electrical power source of 24 or 48 volts is required. The thruster electronics then convert the power and chop the signal correctly to control the movement of the diaphragm. The thrust generated corresponds to the operation of a water jet. 

“We replace the propeller with a membrane that ripples like a fish fin,” Guillemin explains. “It’s a technology that comes from industrial and medical pumps that we have licensed to the nautical field.” 

Assembled with few parts, the thruster does not contain a crankshaft, a reduction gear, or even a rotating joint. Only the circular membrane and the magnets (in direct contact with it) can oscillate, with a maximum rotation of 360° to allow quick direction changes, and the pump is designed to be self-priming. Without mechanical connections, pinion or frinion, the system is low maintenance, with only the membrane subject to wear. The membrane is extremely robust however and can be easily changed when necessary.

There are clear advantages of this new propulsion system since no propeller means that marine life will not risk becoming entangled or killed in the radiating blades. The FinX can also move through polluted waters with ease, allowing algae, plastics and fishing lines to pass through it. Furthermore, it does not consume oil or gasoline, which eliminates the risk of contamination of the water by exhaust fumes and oil leaks.

“When you know that a 5 HP combustion boat engine pollutes as much as 38 cars, there is a real urgency to end this aberration!” adds Guillemin, who believes that this new technology heralds the era of a new kind of boat, necessary for a more harmonious cohabitation with nature.

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