Hi Everyone,
I wish to calculate the feasibility of making a small, light, short-range car which runs on the potential energy of an elastic material.
Many hoovers (vacuum cleaners) have a button on them which you can press with your foot which will reel in the unit's power cable - with quite some force!
Using this principle, it should be possible to make a car which has, say, a light electric motor which is plugged into mains electricity, and which slowly winds up a spring, ready for you to go and drive with it. Because it is so difficult to get good information about the elastic energy density of suitable materials, I have not been able to calculate the feasibility of this system.
Lead-acid batteries, which are used in most electric vehicles, have quite a low energy density.
The energy density of hydrogen, petroleum, gasoline, diesel and LPG are all high - but it is my opinion that this high number is based on a fundamental cheat - they also use the energy of oxygen which does not have to be carried, but which is instead taken from the ambient air.
I think that latex might be a good material - simple, cheap hand-held catapults using latex can now fire ball-bearings with the same amount of energy that a Magnum 44 hand-gun can fire a bullet with (though the bullet will, of course, be far more lethal than a ball-bearing).
So - can any of you material scientists recommend a material?
Also, do any of you have any idea what energy density I might be able to obtain? This number is, IMO, the key to calculating the possible range and performance I might be able to achieve.
Thanks for any help!