Clouds are electrically charged; sometimes the charge is so high we get lightening. Raindrops are therefore charged as they fall. A magnetic field can control the movement of charged particles (think of that oil-drop experiment for measuring the charge of a particle). Put two electro-magnets on the roof of your car, one above the driver, the other above the passenger. Set them up so they generate opposite fields (opposite directions of current flow in the two coils). One magnet will attract positively charged raindrops towards the driver-side (and over the car roof away from the windshield), and repel negatively chared drops. The other will attract negatively charged drips towards the passenger side (and away), and repel positive drops. No rain hits the windscreen!

You could make a circuit linking the windscreen and the magnets so that the wetter a part of the screen was, the stronger the current (and hence magnetic field) over that part would become: feedback.

You better not have, nor drive near anybody with, a pacemaker.

See the link below for a Scientific American article about the charge on raindrops.
-- fc, Aug 18 2000

raindrop charge http://www.sciam.co...ssue/0897amsci.html
(from the Scientific American "Amateur Scientist" column) [fc, Aug 18 2000, last modified Oct 04 2004]

You're confusing electrostatic charge with magnetism -- no magnet, no matter how strong, will "attract" or "repel" charged particles, though magnets will cause moving charged particles to alter their course. (The oil-drop experiment used electric fields, not magnets.)

Also, I believe all raindrops have the same polarity charge, so you wouldn't need two anyway.

Finally, the amount of static charge or magnetism needed to substantially alter raindrops' course would not only mess up pacemakers, it would probably electrocute everyone in the car. But hey, that's a small price to pay... I like the idea.
-- egnor, Aug 18 2000


i was also thinking about repelling rain off a windscreen, using methds other than the wipers - i hadnt thought of that, i like it. i was standing next to my stove and i had just taken a pan out of the sink, and water dripped onto the stove, the water evapourated immediatly, leaving no trace at all. i was thinking about using a heated screen to evapourate the rainndrops as they fall onto the windscreen. But this would mean that the screen would need to be very hot, like the stove. i sort of scrapped this idea, since there would be problems such as; -the heat from the car would be lost very quickly, when youre driving quickly -as youre driving along fast the wind that hits the screen would be heated up, so if you had a skylite on the roof of your car the wind that entered would heat up your car very quickly -there would be alot of power needed to keep the windscreen heated -and if the screen is not hot enough, the heated water could spray off and burn pedestrians -and if you run over someone, they could get badly burned - if youre going around places where the rain is not pure, residues would left - and there would need to be a long time for the screen to heat up, and cool down before and after use

perhaps, the wipers and their conventional motion could be kept but the rubber wipers be exchanged for heated bars, that as they hover over the windscreen, they evapourate the water...
-- hover_dude, Jun 22 2001


yeah, good idea, but what if a stone cracked a small hole in your winscreen, surely, the heat would seep through, and could be very dangerous

surely red hot wipers would be quite distracting

why would you have your sunroof or skylite open when its raining anyway

personally i wouldnt want to wait for some panels to heat up when im driving along in a storm.
-- krea, Jun 22 2001


perhaps some form of high-powered fan could "push" aside the raindrops in a space for several feet in front of your car? not sure if that would work, tho...and it would surely torque off other drivers who are less equipped.
-- Urania, Aug 04 2001


An electromagnetic containment feild against rain would produce a huge EM field - a field which is suspected to cause cancerous tumors. It would also require a great amount of energy (read more than your electrical home heating system probably uses) to produce something with enough charge to deflect raindrops.

Star Trek for a while has been using a similar technology: electrostatic containment fields. Basically the same concept but the field is so strong it deflects most types of energy and matter. The same type of feild is used to contain anti-matter inside the matter/anit-matter reaction chamber (since you can't use a material container for obvious reasons).
-- Odayaka, Aug 22 2001


Or funnel it into the windshield washing reservoir, or the radiator...
-- StarChaser, Aug 25 2001


//perhaps some form of high-powered fan could "push" aside the raindrops in a space for several feet in front of your car?//

How about a blower that just blows all the water within vicinity straight over windshield?
-- thumbwax, Aug 25 2001


A character in the Aurthur C. Clarke novel "The Ghost from the Grand Banks" becomes rich with his patent of glass with a transparent layer embedded inside that vibrates ultrasonically when under current. As a car's windscreen, it just shakes off water and dirt while active. This invention later goes on to put all the window washers out of business.
-- polarbear, Aug 26 2001


I'm feeling magnetically pushed away from this idea.
-- Rain, Dec 14 2003


The good people at Roland-Garros might want to consider investing in one of these.
-- placid_turmoil, May 27 2007


Wow.

//Star Trek for a while has been using a similar technology//

//The same type of feild is used to contain anti-matter inside the matter/anit-matter reaction chamber //

Pssst. Star trek isn't real.
-- Custardguts, May 28 2007


How many Gauss in this thing? Keep it away from my pacemaker.

Of course, turn it on and my keeping my pacemaker away from it will be the issue...

*click-hummmm* *SHRED* "Arrghh! gurgle..."
-- elhigh, May 28 2007


Rain-X. Repels water from windshields (I don't care what the scientific explanation is, it looks like VooDoo to me).

Plus a hood-mounted fan to blow the repelled raindrops away.
-- whlanteigne, Mar 11 2008



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