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Dual Propulsion Human Powered Vehicle

An HPV powered by arms and legs
  [vote for,

Perhaps you have seen those very streamlined recumbents, built with the aim of breaking a speed record.

Could such a record be improved?

Well, all of these record breaking HPV's use the power of the legs alone. And I looked up the speed record of a hand bike in a 200m sprint. It was 52 kph! So it seems to me that if one would be pedaling with both arm and legs simultaneously, that one could go reasonably faster.

In fact, if one was built such a vehicle, I would suggest to use the superman position, that is, laying down belly downwards.In orde to be able to maintain a very good aerodynamic. Of course, an aerodynamic fairing would be needed as well. But I truly believe that such an HPV could break the world speed record. Thank you!

mr Dries, Jul 30 2014


       Rowing bikes use a whole body action with both arms and legs engaged.
pocmloc, Jul 30 2014

       I know but they are slower than many recumbents
mr Dries, Jul 30 2014

       If you could integrate them smoothly, maybe, but the arms are so much weaker than the legs that I would expect the mechanism to combine the two forces would hurt more than the legs would help.   

       Especially when you consider that most top level cyclists who set this records have the upper body strength of a 3 month old.
MechE, Jul 30 2014

       How long does the human have to keep going at full power for these speed records? It seems like it might take a minutes or two to get up to speed. How long do they have to maintain that speed? If it's very long, the cardiovascular fitness of the cyclist may be the limiting factor.   

       If it's s short sprint, then yeah, you might be able to go faster by burning out some extra muscles, but the extra weight of the linkages to harness arm power might be detrimental as well.
scad mientist, Jul 30 2014

       When going for these speed records, it's usually a 200m sprint with flying start.
mr Dries, Jul 30 2014

       Don't cyclists use arms for more leverage against the bike frame?   

       Usain Bolt's average is 37.58km/hr so a mechanically sprung, geared up stride length would be fun. But I don't think you'll get the 5 to 1 ratio an extreme track sprint cycle would have.
wjt, May 18 2020

       // Dual Propulsion
So, 2 people?
sninctown, May 24 2020


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