Designing a front light for cycling - Page 1
Forum section: electronics / projects

author: zanzeoo
author_rank: Contributor
timestamp: May 11, 2014, 09:57:41 am
content: Hi everyi 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 DRAGONhttp://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

author: stef_r
author_rank: Contributor
timestamp: May 11, 2014, 01:46:13 pm
content: 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.

author: Isad
author_rank: Frequent Contributor
timestamp: May 11, 2014, 01:55:18 pm
content: 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=item20d37a262fOrYou 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 needa bigg heat sink for this onehttp://www.ebay.com/itm/2pcs-10W-LED-White-High-Power-1100LM-LED-Lamp-SMD-Chips-Light-Bulb-/331093412789?pt=LH_DefaultDomain_0&hash=item4d16b48bb5You can get the Led driver for cheap and "waterproof" they sayhttp://www.ebay.com/itm/10W-LED-Driver-Power-Supply-AC90V-265V-Waterproof-IP67-High-Power-/400586956393?pt=US_Lighting_Parts_and_Accessories&hash=item5d44d7de69

author: staxquad
author_rank: Frequent Contributor
timestamp: May 11, 2014, 02:59:38 pm
content: 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 compactawww.taskled.com"b3Flex" driver with modes from georges80 on this forum3 x Cree XML U2 1C colorhttp://www.cutter.com.au/proddetail.php?prod=cut1447Cute-3 lens (select wider for handlebar and narrower for helmet)http://www.cutter.com.au/products.php?cat=XM+Triple+Lensmomentary 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.htmla 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_.htmla 12v 10a power supply for the charger from ebaya variety of gauges of silicone wireconnectorshousing, driver heat sink, led heat sink, light mount for helmet or handlebar

author: Isad
author_rank: Frequent Contributor
timestamp: May 11, 2014, 04:02:05 pm
content: staxquad described prety well now basicly to well!

author: NiHaoMike
author_rank: Super Contributor
timestamp: May 11, 2014, 04:05:36 pm
content: What about a generator activated on braking in order to reduce battery requirements?

author: zanzeoo
author_rank: Contributor
timestamp: May 12, 2014, 03:05:37 pm
content: Thank for yours replies everyoneQuote from: NiHaoMike on May 11, 2014, 04:05:36 pmAnd a flux capacitor to time travel

author: nctnico
author_rank: Super Contributor
timestamp: May 12, 2014, 03:22:30 pm
content: 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.

author: mark03
author_rank: Frequent Contributor
timestamp: May 12, 2014, 05:45:10 pm
content: Two suggestions:1) The Candlepower forumswww.candlepowerforums.comhave 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.htmlBTW 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.