Tadpole style recumbant - with the rear single wheel doing the steering with the front two wheels fixed - plausible?
Now in a way you couldn't really call this a bike anymore, as it will not be pedal powered. Instead I am gearing one of my wheelchair motors left over from one of my robots to power the rear wheel. It will be kinda like driving a boat on land. So... am I nuts for trying it this way. Included a quick BASIC concept sketch.
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I'd be worried that trying to steer from behind would be unstable -- the farther off-axis you are, the more the motor will try to push you even farther off-axis. It might be drivable but I think you'd be fighting it continuously.
(As opposed to going the other direction, where the vehicle would tend to pull itself back into going straight. Or motorizing the forward wheels and letting the steering/rudder wheel's drag tend to pull it back into straight-line position.)
Possible, but maybe not plausible.
(As opposed to going the other direction, where the vehicle would tend to pull itself back into going straight. Or motorizing the forward wheels and letting the steering/rudder wheel's drag tend to pull it back into straight-line position.)
Possible, but maybe not plausible.
Yes, you are probably right. I do have the option of motorizing the front as well, just as easy with the supplies I have to work with, "I have several work type trykes that I could use". Just being a little too lazy I think. Was seeing if it possible to avoid setting up a traditional tadpole steering system is all. Thanks for the input, its good to have people to bounce ideas off of.
One thing that might help, use a very large rear tire, it will limit how far off center the driving wheel could push you, but overall, its probably a better idea to motorize the front.
Buckminster Fuller designed and built three versions of a three wheeled car with single rear wheel steering. His car had drive going to the front wheels though. For many years I labored under the misconception that because the engine was mounted in the rear and it had rear steering that the engine drove the steerable third wheel. I was mistaken.
Jun 20, 2011. 11:34 AMpierce-custom-bikeworks
says:
call me nuts but it could be done. instead of trying to steer with the rear wheel set it up like an old tail dragger aircraft.
allow the rear wheel to move freely and control it with a stand alone break system for each front wheel.
example to turn right apply break pressure to the right wheel to turn left apply brake pressure to the left
but if you do it this way you wouldnt want to put the engine on the back wheel
allow the rear wheel to move freely and control it with a stand alone break system for each front wheel.
example to turn right apply break pressure to the right wheel to turn left apply brake pressure to the left
but if you do it this way you wouldnt want to put the engine on the back wheel
May 30, 2011. 5:12 PMAndale_The_Great
says:
i once drove a car with rear wheel steering (it was someone with too much time and money being funny) and it was freaking impossible to get used to, everyone kept crashing it into stuff by turning for too long or too soon
Not a nut at all. This has been done many times.
HOWEVER There are good reasons for all rear wheel steering vehicles being relatively SLOW! -
At high speeds it tends to become unstable. At low speeds you are OK but find it hard to steer away from kerbs and walls.
There are loads of great resources on line for recumbent builders. I built mine 20 years ago and still rid it.
The motor is a good idea as the long chain run for a tadpole is a pain.
Some resources below.
http://www.google.co.uk/search?client=firefox-a&rls=org.mozilla%3Aen-GB%3Aofficial&channel=s&hl=en&source=hp&biw=&bih=&q=velomobiles&btnG=Google+Search
http://www.recumbents.com/home/
http://www.mosquito-velomobiles.com/index.htm
http://www.wannee.nl/hpv/abt/e-index.htm
http://www.google.co.uk/search?client=firefox-a&rls=org.mozilla%3Aen-GB%3Aofficial&channel=s&hl=en&source=hp&biw=&bih=&q=rear+wheel+steering+recumbent&btnG=Google+Search#q=rear+wheel+steering+recumbent&hl=en&client=firefox-a&hs=mUg&sa=G&rls=org.mozilla:en-GB:official&channel=s&prmd=ivns&source=univ&tbm=vid&tbo=u&ei=XFrXTcy7AsHPhAfLuP3CBg&ved=0CDAQqwQ&bav=on.2,or.r_gc.r_pw.&fp=ec64042ba2cabeca
http://recumbentsartandpoems.blogspot.com/2008/12/many-of-you-might-wonder-why-build.html
http://www.youtube.com/watch?v=v3lnRmSWKPE
HOWEVER There are good reasons for all rear wheel steering vehicles being relatively SLOW! -
At high speeds it tends to become unstable. At low speeds you are OK but find it hard to steer away from kerbs and walls.
There are loads of great resources on line for recumbent builders. I built mine 20 years ago and still rid it.
The motor is a good idea as the long chain run for a tadpole is a pain.
Some resources below.
http://www.google.co.uk/search?client=firefox-a&rls=org.mozilla%3Aen-GB%3Aofficial&channel=s&hl=en&source=hp&biw=&bih=&q=velomobiles&btnG=Google+Search
http://www.recumbents.com/home/
http://www.mosquito-velomobiles.com/index.htm
http://www.wannee.nl/hpv/abt/e-index.htm
http://www.google.co.uk/search?client=firefox-a&rls=org.mozilla%3Aen-GB%3Aofficial&channel=s&hl=en&source=hp&biw=&bih=&q=rear+wheel+steering+recumbent&btnG=Google+Search#q=rear+wheel+steering+recumbent&hl=en&client=firefox-a&hs=mUg&sa=G&rls=org.mozilla:en-GB:official&channel=s&prmd=ivns&source=univ&tbm=vid&tbo=u&ei=XFrXTcy7AsHPhAfLuP3CBg&ved=0CDAQqwQ&bav=on.2,or.r_gc.r_pw.&fp=ec64042ba2cabeca
http://recumbentsartandpoems.blogspot.com/2008/12/many-of-you-might-wonder-why-build.html
http://www.youtube.com/watch?v=v3lnRmSWKPE
Looked inot it a bit more, apparently this has been tried from time to time over and over again. No one really seems to have any success, back to the drawing board...
It's true, rear-steer trikes are never really very nice to ride because they are so difficult to steer. If you need inspiration, be sure to check out Atomic Zombie, where you'll find tons of trike designs, some motorized.
I'm reminded of a powered ride on pallet jack.
They have the power going to the rear wheels with the steering constrained exactly to the vertical axis, and a long lever for the operator to adjust the steering - they do have ork's suggestion of instability at high speed when in 'pusher' mode, so you always have to drive 'forward' backwards dragging the load.
They have the power going to the rear wheels with the steering constrained exactly to the vertical axis, and a long lever for the operator to adjust the steering - they do have ork's suggestion of instability at high speed when in 'pusher' mode, so you always have to drive 'forward' backwards dragging the load.
yup, I may just go for a ride on one of those right now... you know, for kicks at 1 in the morning... the night shift is very slow - what can I say
I too am on night shfit. yay! No pallet jack for me. There IS a forklift in the building, but if I was driving it, the police would show up.
Nice, I on the other hand am the only person present for quite some distance. Enough so that I have to be equipped with a gps spot unit... A large now defunct pulp and paper mill is more or less my playground, not as cool as it sounds, but sometimes...
May 21, 2011. 8:58 AMorksecurity
says:
Insecurity detail, hm?
That's essentially how the writer Spider Robinson got started -- as he puts it, he had a job "guarding a hole in the ground to keep anyone from stealing it" -- which left him with lots of time to work on his writing.
That's essentially how the writer Spider Robinson got started -- as he puts it, he had a job "guarding a hole in the ground to keep anyone from stealing it" -- which left him with lots of time to work on his writing.
More or less, I used to work at the mill when it was running. Then i was called back a year later to work as a first aid attendant for various companies who bought the paper machines. They also need extra plant protection officers, so I put my hand up. Gives me lots of free time that's for sure, lets just say a flurry of new instructables has started
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