Amphibious cycle
An amphibious cycle is a human-powered vehicle capable of operation on both land and water. Some designs allow riding directly into and out of the water, other semi-amphibious cycles must be converted in order to change from one mode to the other.
Early designs
First designs and patent applications appeared in the late 1860ies for amphibious tricycles using large buoyant wheels and thus able to be driven directly in and out of the water.[1]
In 1895 the German engineer Max Wenkel experimented sucessfully with water tricycles near Hannover. The two rear wheels were fitted with small paddles for water propulsion.
In 1943 David Vigo, in 1963 Harry Leiberman and in 1971 Ernesto Moraga were awarded US-patents 2,323.261, 3,091,209 and 3,606,856 for their water tricycles. These had been preceeded in 1903 by Anton Piller with US patent 728,758 for a similar water quadracycle, and other designs using buoyant ball wheels around since the 1860ies.
A similar two-wheeler, E. Fabri's Cyclomer, was demonstrated in Paris in 1932. As the dynamic stabilty of a road bicycle does not work on the water, four additional stabilizing ball wheels were fitted that are folded down on the water.
Other semi-amphibious bicycles were constructed using fully roadworthy safety bicycles. The first known such design was developed in 1910 by Baumgartner and Hirth and demonstrated on the Rhine. In water mode three floats are folded down and a propeller drive connected.
In 1915 Julius Bettinger patented and demonstrated a semi-amphibious bicycle on the Neckar using two inflatable floats. It was propelled by paddles connected with levers to the pedals.
Contemporary designs
A design which has received much coverage is "Saidullah’s Bicycle."[2][3] The bike uses four rectangular air filled floats for buoyancy which propelled using two fan blades which were attached to the spokes. "Moraga’s Cyclo Amphibious"[4] uses a simple tricycle frame to support three floaters which provide both the flotation and thrust. The wings on the powered wheels propel the vehicle in a similar way to a paddle wheel.
Another design is the SBK Engineering Shuttle-Bike. It consists of two inflatable floats with straps that allow the carrying of a bicycle by the passenger. The ensemble, when deflated, fits in a backpack for carrying by the cyclist.[5]
Another amphibious vehicle is that of seven engineering students at the University of Southampton.[6][7] The "Amphibious Cycle" combines a recumbent frame with separate floats, and is propelled using a paddle wheel. A speed test on water achieved an average speed of 1.12 m/s. The cyclist could transition the cycle in and out of the water while unassisted. This prototype has real applications in urban areas of flooding, as well as applications in the leisure industry.
Another recent design was developed by Ebrahim Hemmatnia for his voyage around the world. This velomobile was called the Melanie.[8][9]
All terrain
Competitions for human-powered all-terrain vehicles as kinetic works of art started 1969 in California as the kinetic sculpture race. These often rather large and outrageously decorated vehicles must travel considerable distances on roads including hills, water, mud and sand.
References
- ^ Schult, Joachim (1974). Curious Boating Inventions. London: Elek Books Limited. ISBN 0 236 17627 7. Retrieved 27 March 2025.
- ^ Shourie, D. (2006) Grassroots inventions "The Tribune", Chandigarh, India. 17 February 2006.
- ^ This has been featured on both the Discovery Channel and BBC News
- ^ Moraga, E.O. (1969) 21 September 1971 "Cyclo Amphibious" US Patent 3,606,856.
- ^ SBK Engineering Shuttle-bike
- ^ Anthony Chesshire, David Edwards, Simon Halford, Joanna Hutchinson, Jack Marriott, Andrew Webster & Simon Wiles (2008) "Design Build and Test an Amphibious Cycle" School of Engineering Sciences, University of Southampton.
- ^ featured in the Southern Daily Echo (5 June 2008) and The Daily Telegraph (6 June 2008)
- ^ Ad Infinitum amphibious bicycle
- ^ Ad Infinitum bicycle