Designing a front light for cycling

[zanzeoo]

Hi every

i sometimes have to bike in the wood at night ( for competition ) . I need a good front light so i would like to desing it .

i need some advices about what LED technology and driver i should use.

what about OSRAM DRAGON http://fr.rs-online.com/web/p/led/7080772P/ ?

and a LM3409 driver ?

i will use a small battery 12v or less , i need 4 or 5 hours of battery life.

thank for you replies

[stef_r]

What you alsocould look for are special devices to control Power LED applications.
If you should combine it with a microcontroller, the options are endless.
(automatic lower light output when battery goes below a certain threshold, PWM, etc.)

You should also be able to do this with a minimum of components.

[Isad]

You could try these out they are dirt cheap and you need only a driver for them and a lipo batter:
http://www.ebay.com/itm/50-Pcs-1W-Warm-White-High-Power-Led-Lamp-Beads-80-100Lm-1Watt-wholesale-/140986951215?pt=LH_DefaultDomain_0&hash=item20d37a262f

Or

You could go crazy with this one but you will need 2 or much more lipo and you would look like a UFO LOL but you will need
a bigg heat sink for this one
http://www.ebay.com/itm/2pcs-10W-LED-White-High-Power-1100LM-LED-Lamp-SMD-Chips-Light-Bulb-/331093412789?pt=LH_DefaultDomain_0&hash=item4d16b48bb5

You can get the Led driver for cheap and "waterproof" they say
http://www.ebay.com/itm/10W-LED-Driver-Power-Supply-AC90V-265V-Waterproof-IP67-High-Power-/400586956393?pt=US_Lighting_Parts_and_Accessories&hash=item5d44d7de69

[staxquad]

just a typical light example to give you ideas
(5 hours of racing, that's a lot of light; racing, you're going fast, so usable light required; 5 hours time requires lots of AH)
something performing, reliable, versatile, light and compact


a www.taskled.com "b3Flex" driver with modes from georges80 on this forum



3 x Cree XML U2 1C color http://www.cutter.com.au/proddetail.php?prod=cut1447



Cute-3 lens (select wider for handlebar and narrower for helmet)  http://www.cutter.com.au/products.php?cat=XM+Triple+Lens


momentary switch to control the driver (logic switch, no current)


LiPo 8AH 3S1P (if you are team racing and you just do your laps in between the others, you need a number of smaller batteries to last just your laps) http://www.hobbyking.com/hobbyking/store/__16225__ZIPPY_Flightmax_8000mAh_3S1P_30C.html



a balancing charger to charge fast and keep the battery performing and lasting (this quality minimum) http://www.hobbyking.com/hobbyking/store/__5548__IMAX_B6_50W_5A_Charger_Discharger_1_6_Cells_GENUINE_.html


a 12v 10a power supply for the charger from ebay


a variety of gauges of silicone wire


connectors


housing, driver heat sink, led heat sink, light mount for helmet or handlebar



 

[Isad]

staxquad described prety well now basicly to well  !

[NiHaoMike]

What about a generator activated on braking in order to reduce battery requirements?

[zanzeoo]

Thank for yours replies everyone

What about a generator activated on braking in order to reduce battery requirements?

And a flux capacitor to time travel   

[nctnico]

Whatever you do: don't let it blink. When driving a car it is very hard to tell where a cyclicst with a blinking headlight is going.

[mark03]

Two suggestions:

1) The Candlepower forums www.candlepowerforums.com have an entire forum dedicated to ridiculously high-power bike lights.  I would take a look at what folks are building now, and steal the best ideas.

2) Have a look at my design.    http://www.keteu.org/posts/bikelight.html

BTW while blinking may impair distance judgement, it does make you as a cyclist more visible, especially if the driver's attention is not on the road.  I use a super-bright flashing mode in the daytime and around dusk, and steady after dark.  Actually, I added a mode that is medium-power background with high-power blinks.  I like it.  One of the advantages of having a tiny MCU in there that you can program.