Road vehicles are required to have autonomous LED parking lights front (white) and (rear) red.

The battery - probably a 3.6 V LiON cell - is independant of the vehicle main battery.

The LEDs are activated whenever (a) the vehicle's engine is stopped and (b) a photocell detects ambient light levels below a preset minimum.

When the engine is running, the cell is charged from the alternator.

In daylight, the cell is charged by a small photovoltaic.

Wherever the vehicle is parked, when it's dark, lights come on automatically.

The cell is sized so as to give a minimum of 3 nights endurance without recharging.
-- 8th of 7, Feb 05 2010

No, but we got to watch one, and it wasn't amusing, even for us.
-- 8th of 7, Feb 05 2010


Same as bicycle lights - flash them to save power. I like this idea. Imagine the local supermarket car park at dusk, and Christmas, too!
-- Ling, Feb 05 2010


Now if you had a similar setup for a mooring ball, finding your mooring at night would be a lot easier. And with all that sunlight or wave action turned into energy to charge the battery, it could stay charged all summer.
-- halb gekocht, Feb 05 2010


This is a great idea. but I can't help thinking that there can be few man-made objects that this could not usefully be applied to. Obviously the flash rate would need to be customised for objects with no power supply which spend a lot of time resting in a dim environment (e.g. books on a library shelf) but I think this could liven up our built environment no end.
-- pocmloc, Feb 06 2010


Given the tiny power drain of an LED and the capacity of a car battery, just run it off the normal battery. It won't have much more impact than keeping the clock going.

I think a street full of parked cars at night would look lovely like this.
-- wagster, Feb 06 2010


// think a street full of parked cars at night would look lovely like this//
It should be possible to get them to do that fire-fly synchonisation thing - that would be cool!
-- coprocephalous, Feb 06 2010


Could I customize the arrangement to create a unique lighting pattern for my car?
-- Riki, Feb 07 2010


[-] for mandatory anything, [+] for the rest of it
-- afinehowdoyoudo, Feb 07 2010


Yes, but we're talking thousands of super-bright LEDs, visible from outer space
-- pocmloc, Feb 07 2010


The point is that it's "always" on. It's a few milliamps, yes, but leave a vehicle parked for a month or so and it'll flatten even a large accumulator.

Hence the concept of "autonomy" using a photovoltaic.

Should also be available as a cheap, easy retrofit or aftermarket accessory to existing vehicles.

Flashing is a good idea. Saves energy (even a 3:1 duty cycle would make a huge difference to endurance) and would be more visible than a static luminaire.

The firefly-flash thing, well, could be done ...
-- 8th of 7, Feb 07 2010


It'd be fun to spell out things for airline pilots by leaving cars parked in unusual ways in parking lots and such.
-- RayfordSteele, Feb 08 2010


While this would (and does) work for individual objects, like the flashing LED lights attached to skips etc., I suspect it would lose it's effect if every car had them. Once the side of every street is carpeted with flashing points of light, it becomes very difficult to judge the distance of any individual light.

Perhaps it would work better if it sensed the light from the headlamps of an approaching vehicle and then switched itself on.

Or maybe just fit mandatory reflectors, coupled with some mandatory legislation about looking where you're going and not parking in stupid places.
-- Twizz, Feb 08 2010


[+]. There should be an over-ride switch for this, however, else you will be "that guy" at the star party/covert reconnaissance mission.

Also: What [iron_horse] said.

Resistance to mandated safety protocols is NOT futile!
-- MikeD, Feb 08 2010



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