Quote:
Originally Posted by Turtle
As Craig showed so succinctly, no matter the type of drive or the speed, there is a theoretical limit to how far any vehicle can roll given a 1 kilo weight falling 10 cm onboard to power it.
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Yeah, if friction is constant then there is a limit
I think all efforts should be geared toward lowering friction including the car's overall weight and the speed (which should both be as small as possible). I'm actually surprised the instructions explicitly say that it should coast when the weight is completely fallen considering the best performing vehicles will never go fast enough to coast.
Quote:
Originally Posted by Turtle
Now you raise an interesting question though, and a different challenge which is how to keep the vehicle under power for the entire ~10 meter trip? I have some ideas, what about y'all?  (might be a subject for a different thread?  )  |
Do you mean how to distribute the energy over a long distance? I should think making the axle small (the spool where the string attaches to the axle) and the wheels with a large diameter should do it. I'd personally use a 120 mm CD for the wheels then play with the axle size making it smaller if the car goes too fast and larger if it doesn't move.
The best-performing string would be another interesting issue. I'd think as thin as possible and as not-stretchy as possible. Maybe the lightest fishing line (6 lb?) or the E string on a guitar... maybe?
Any place where the string changes directions (there should just be one directly above the weight) would be well-served with a pulley. I've run into some small aluminum ones in model plane kits which were something like this:
ALUMINUM PULLEYS from Aircraft Spruce
Uh... what else... balsa or bass wood. 3 wheels are better than 4. There only needs to be 3 legs holding up the pulley which holds the wight (think of a Naive American teepee with only 3 poles).
Anyone up for an Hypography build off
~modest
