velomobile conference served as the debut for several new velomobile designs from around the world and I found the most inspiring was Harald Winkler’s completely custom built 12kg velo, a vehicle so light that he began his presentation by carrying it on stage holding it high above his head.
Harald’s velomobile was designed especially for geting around his hometown which has smooth roads but is hilly and has a lot of intersections. Hence, the overriding concern was to reduce weight and make acceleration and getting up hills as easy as possible. His design incorporates a carbon fiber perimeter frame/seat structure, a delta layout using an offset chain run to drive a single rear wheel and a foam body, employing his self-developed MEUFL foam technology, that weigh little more than 1.5kg. Frontal area is extremely small due to its road-hugging narrow, low profile design as well as 16″ wheels that might just be the smallest ever used on a velomobile.
There were several other clever features such as custom made tires (larger diameter tires were sectioned and glued together to make high performance tires that are otherwise unavailable for 16″ wheels). a plastic steering u-joint with adjustable pre-load and most conspicuously, a couple of small propellers that produce a high pressure air bubble at the front of the windscreen, eliminating the need for windshield wipers to clear rain from the driver’s view.
As clever as the features included, the design is also notable for what it leaves out. There is no suspension nor typical crank assembly; the pedals are carried by an s-shaped carbon fiber tube that transmits pedaling force to a sprocket mounted to the left-side carbon fiber spar, leaving the volume between the seat and crank completely unobstructed. Besides making entry/egress much easier, to the user it becomes less a mechanical tool and much more a friendly consumer product designed to satisfy human needs first.
In many ways this vehicle would be impractical for American roads yet it fits its intended environment and Harald’s needs perfectly. It is a great example of minimalist ingenuity and made me realize how complex the current Turanga design is, despite the fact that simplicity was one of its guiding design principles. I’ve learned there’s always a little more that can be done to make less, if you catch my drift.
Harald’s paper, along with the other papers presented at the seminar, can be found here.