Electric boats could soon be getting even quieter and more maneuverable, according to Yahama. The company's new Harmo steering and propulsion system is promised to deliver on both counts.
At first glance, the Harmo propulsion unit looks like a regular outboard motor – one section protrudes horizontally out from the back of the watercraft, while the other points vertically down from that top section, into the water.
Unlike the case with a traditional outboard, though, the entire thing doesn't swivel from side to side. Instead, only the vertical section does, pivoting almost 90 degrees relative to the top. Yamaha states that this setup allows for greater maneuverability, including on-the-spot turning.
At the bottom – and under the water – is the combined propeller/motor unit. It incorporates a Drive By Rim motor, in which a ring of sequentially-activated electromagnets surrounding the steel propeller are used to spin it in either direction. This technology reportedly allows for more thrust to be generated at lower prop speeds, resulting in fewer vibrations and less noise.
Everything is controlled by a cockpit-located joystick. Additionally, when the boat is out of the water, the propulsion unit can be flipped up to get it out of harm's way.
Yamaha will begin trials of the Harmo system on Aug. 7th, on cruise boats in Hokkaido's Otaru Canal. The setup is illustrated in the following video.
Source: Yamaha