Radical three-wheeler puts the engine to the back and the power to the front
by Ben Coxworth · New AtlasThree-wheeled cars are already a pretty unique bunch, but the Dragonfly Three Wheeler stands out even amongst them. It features a novel drivetrain layout which is claimed to boost traction and stability, amongst other selling points.
Currently in functional prototype form, the Dragonfly was designed and built by a team led by American mechanical engineer Greg Kunsch. He previously worked at Northrop Grumman and spinoff company Huntington Ingalls Industries, where he helped design aircraft carriers and nuclear submarines.
As you can see in the photos, his three-wheeled, road-legal "autocycle" sports a full-steel body in the classic tadpole configuration, with the two wheels in front and the single wheel in the rear.
This design seats the two side-by-side occupants in the widest part of the vehicle – down between the two front wheels – thus lowering the center of gravity and maximizing stability when taking corners at speed.
In the vast majority of tadpole three-wheelers, the rear wheel is the one that's powered. Some electric tadpoles are front-wheel-drive, via hub motors in the two front wheels. The Dragonfly, however, is claimed to be the world's first mid/rear-engine front-wheel-drive three wheeler.
According to Kunsch, putting the power to the two front wheels doubles the traction which is necessary for vehicles with higher-powered engines – in its current incarnation, the Dragonfly sports a 200-hp, 2.4-liter DOHC gas power plant.
Putting that engine towards but not right at the rear end reportedly distributes the weight more evenly, for better handling and stability. Greg adds that most tadpoles are rear-wheel-drive simply because that makes them easier to engineer and cheaper to build.
Along with its unique drivetrain, some of the Dragonfly's other features include a manual 5-speed transmission, an electrically raised front canopy (instead of doors), a removable roof, 8-point roll bars, power steering, and a self-leveling adjustable-height air suspension system.
Kunsch tells us that the vehicle's rather un-aerodynamic, sharp-lined design is the result of keeping costs down on the present prototype. And yes, he does plan on making an electric model – perhaps even a whole family of EVs – although he won't be using hub motors due to two main issues.
"The first is the unsprung weight," he says. "These motors are 40-ish pounds [18 kg], and that means both a very harsh ride and handling of impacts. The second issue is that there really isn't a large base or proven use at scale. To date nobody is really using them on a production car at scale."
Greg has no plans to sell directly to consumers, but he does hope to license the technology to partnering manufacturers. Interested parties can contact him via the Dragonfly website.
You can see the prototype rollin' down the road in the following video.
Source: Dragonfly