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Author Topic: Human powered vehicles  (Read 2414 times)

Offline P K Pillai

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Human powered vehicles
« on: 27/07/2013 02:20:42 »
In human powered vehicles, if the 360 degree pedal rotation is replaced by,say,60 degree reciprocating treadles,the leverage can be doubled.Wasteful leg movement can be reduced.Why are reciprocating treadles not used?


 

Offline syhprum

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Re: Human powered vehicles
« Reply #1 on: 27/07/2013 08:28:47 »
They were in fact used on the plate layers trolleys on the railways if such things are still used
 

Offline RD

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Re: Human powered vehicles
« Reply #2 on: 27/07/2013 09:01:38 »
In human powered vehicles, if the 360 degree pedal rotation is replaced by,say,60 degree reciprocating treadles,the leverage can be doubled.Wasteful leg movement can be reduced.Why are reciprocating treadles not used?

A treadle scooter has been patented ...


http://www.patentbuddy.com/Patent/5110148

If they were more efficient at harnessing human energy [ergonomic] than cycling then why haven't I seen  one winning the tour de France ?


Incorporating arm movement may extract more energy ...


They were in fact used on the plate layers trolleys on the railways if such things are still used

Cycle version [railbike] is still available ...


http://www.cco.net/~railbike/railbike_tours.htm
« Last Edit: 27/07/2013 09:14:51 by RD »
 

Offline CliffordK

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Re: Human powered vehicles
« Reply #3 on: 27/07/2013 11:15:33 »
The circular motion of the crank may not be as bad as you think as walking or running involves both a vertical and horizontal component of motion.  That may, in fact, lead to the use of more muscle groups than a straight vertical treadle.  The crank may also create a sinusoidal force vector which may be natural for the body. 

If you connected a treadle to a crank, it would add extra complexity and extra points of motion, or friction.  Another issue with a treadle connected to the crank is that there would be points at the top and bottom of the revolution where the crank would be difficult to restart, and force into forward motion.

A pedal assisted car might overcome some of those issues with electronics. 

There have been efforts to improve the ergonomics of a crank such as the Biopace Crankset, although I don't believe it has been widely accepted, and apparently at least the Biopace is no longer made.

One human powered car prototype uses a rowing action rather than a pedaling action.  I don wonder if it could have had a fixed seat position, and only moved the pedals and arm portion.
 

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Re: Human powered vehicles
« Reply #3 on: 27/07/2013 11:15:33 »

 

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