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Thought you all might be interested in one of my endeavours. I call it the world's fastest manual wheelchair, in fact it is a streamliner hand trike, with chain driven front wheel.
Our pilot is Greg Westlake, a member of the Canadian Paralymic Hockey team. In our first outing last month at the Ford Proving Grounds Track we successfully beat the world one hour average land speed record for an arm powered vehicle at 20.757mph, or 33.406km/hr. On the week of Sept14 we will be attempting to beat the all out hand powered land speed record at Battle Mountain Nevada. Our goal is to exceed the existing record of 45km/hr by at least double. We have the machine and the pilot to do it.
The trike is an 8.5 foot long carbon fibre monocock tub and top shell, with one steering and drive wheel in the front and two wheels in the back. The bare tub weighs in at 7 pounds and is the only structural component of the trike. The rear and front wheels are attached to the tub via carbon/foam bulkhead ahead and behind the pilot. The top shell weighs under 3 pounds. All assembled with drive train and wheels it comes in at a bit more than I wanted, but still a respectable 39 pounds. We will shave some weight off of it for next year by making new wheels. These ones are carbon fibre with aluminum honey comb. I figure by refining our fabrication technique we will be able to cut a few pounds off of these.
The drive train is a modifies road bike gear set. We made a quick change jack shaft gear cluster with derailer so that we can quickly fine tune the gearing, as well create a compact drive and steering package.
For more information and photos here is a link to our Facebook page Login | Facebook
And Photobucket link. Ford Human Powered Speed Challenge pictures by ColleenDalgliesh - Photobucket
 

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sweet! Does the weight really matter much for sustained speed? I know it increases frictional losses at the bearings and tires. However if it is a constant maintained speed, I wouldent think saving a pound or 2 would help much. Certainly areo is of the highest importance however...
 

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This would be pretty damn superbad, even if you hadn't set a record on your first time in competition! Congrats to your team. :up:

Doubling the existing top speed mark? :eek: But it sounds like you are the guys to do it if it can be done. Kudos to you for your vision; good luck...
 

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Fantastic stuff!!!

sweet! Does the weight really matter much for sustained speed? I know it increases frictional losses at the bearings and tires. However if it is a constant maintained speed, I wouldent think saving a pound or 2 would help much. Certainly areo is of the highest importance however...
Agree - I suspect the biggest improvements you will be able to make are going to be in friction reduction (rolling resistance and bearings)
Awesome. Congratulations!

Get ya some of those ceramic Bearings that Lotus uses in their Soap Box Racer and break the WW again!
What he said :)
 

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there is a guy here - not disabled - that brings a non-fairing one out on some of the tempo / interval rides. he has no problems sticking in a 30+ mph pace for extended periods. very compact areo and (in his case) can throw his entire body into the cranks.

you might also think about those new fangled (german i think) geared hubs... the recumbant velo racers use them. might simplify your drivetrain.
 

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I wonder if there is a way to increase the powerplant output by a more bio-designed method than hand cranks. The magor muscle groups of the uperbody are the latissimus and pecktorals. These are definately used in the cranking motion but I think the biceps and uper arm muscles may be too heavily involved in the motion. Maybe a rowing type motion (hard to engineer I realize),,,
 

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Great stuff. :bow:
 

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Discussion Starter #11
Thanks all for the comments and support.
Now to answer some of the questions and comments:
Weight: it is true that the overall weight has little effect on it once at speed, but the issue is the power needed to get to that speed. We have very limited power, so moving a heavy trike for a stand still will consume valuable energy.

Rolling resistance is one of our prime concerns. We are using special 180 PSI tires to keep the contact patch and tire deformation to a minimum. The bearings in the wheels and drive train are high quality, not ceramic (no budget for them). We remove the dust covers and grease and use light synthetic oil on them. We will replace of clean them between events.

Aerodynamics: Well, it was sort of a guess. The biggest challenge was to come up with a shape that allowed the pilot enough room to power the trike. Unlike leg power, our pilot's body position is much more critical. He is using relatively small muscle groups, and in more total body to generate power as opposed to pure legs and hips as in a recumbent bike. As seen in the photos, our pilot is actually perched above the cranks, so there is a very large frontal area...not good for aerodynamics. We had hoped to get fairings on the wheels to clean up the air, but have not had the time to get them done.

Biomechanics: I have been developing equipment for athletes with disabilities for over 25 years. The one thing that is a constant is that one can not make assumptions as to what will work for an individual. In the case of Greg we are using a rowing action to drive the cranks. As anyone who has paddled or rowed competitively knows, most of the power comes from truck and legs. This is true for Greg as well even though he is missing some of the leg component. He has also found that he likes to change his body position depending upon the task. Much mike an upright cyclist, when accelerating he likes to use his body weight to generate torque (a cyclist stands) Greg leans over the cranks. When up to speed he sits up straighter, and spinds quickly at the given resistance.

There...hope that was not to long and answer
 

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great info and cool work. The project is a great combo of engineering and human determination....
 

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SUPER FRICKIN' AWESOME!!! :clap: :up:
 

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This is really great!

You should send a note to Nick Adams over at Lotus to let him know what you guys are doing and maybe get him interested enough to possibly throw some Lotus brainpower into the mix.
 

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Discussion Starter #15
This is really great!

You should send a note to Nick Adams over at Lotus to let him know what you guys are doing and maybe get him interested enough to possibly throw some Lotus brainpower into the mix.
That's a cool idea...MkII for next year, in yellow and green
 

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There we go....actually, I am painting it now. Do to heat we are painting the top shell white with a stripe....boring, I know but it will have to do. If we get a sponsor aside from myself we can paint it any colour they like, specially green and yellow. Will blend in with my garage.
 

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Discussion Starter #20
No, not a racing strip on the top but a tapered upswept strip on the side that starts thin at the nose and flairs out at the tail
 
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