What's a good e bike headlight?

It is automatic, it computes the RMS and does the control. You are right, the software is somewhat complicated, but a cheap little 8 pin microprocessor can easily handle it. The circuit is electrically and mechanically simple. The software handles ramping the PWM and computing the RMS and doing feedback to get the desired value.
 
You can do pwm with a picaxe controller or arduino, I think its even possible with a simple 555 chip.
 
The chip I used was the ATTiny45, which is a smaller flash version of the ATTiny85 which is sometimes used to run a subset of Arduino. It runs at 8 million instructions per second.

You can use a 555 to generate fixed PWM which would work for a fixed voltage reduction ratio, but you will need something like a micro to do the RMS calculation if you want regulated voltage on the bulb.

The picaxe is a lot more limited than the Arduino and this may or may not affect the ability to do a program like this. I calculated the root mean square voltage value every cycle at 240hz with 32 bit arithmetic, the picaxe has much lower performance, but would probably suffice for this application.
 
toshy said:
When I pushed the led with a finger, it worked, but the brightness was around 5% as it should be.
Mesaured the voltage on the "broken" led, and it reads the same voltage as battery (53V), on the working one, the voltage is 3V at the led. So I guess something blew up...
Well, took it out from the housing so I could try my soldering skills, put it in the oven for a few minutes...Still the same story.
Here is the board, I guess there's nothing fixable? :)


I'm getting new ones, I ll have to pay a few bucks for the shipping, but I m still in doubt how long will it work.


You can buy these leds just by themselves off ebay for a few pence / cents, easy to replace with an iron in 2 mins.
 
@crea2k, I'm afraid something else had to blew up at the first lamp if you reread my quoted text.
@izeman, no reverse engineering. It worked on 12V, but when I connected again it to my battery, I had some fireworks.

And no new lamps - told me they are out of stock :D Hope I'll get a full refund, because both lamps are faulty. One is fried, one is working only on high beam.
 
Alan B said:
The chip I used was the ATTiny45, which is a smaller flash version of the ATTiny85 which is sometimes used to run a subset of Arduino. It runs at 8 million instructions per second.

You can use a 555 to generate fixed PWM which would work for a fixed voltage reduction ratio, but you will need something like a micro to do the RMS calculation if you want regulated voltage on the bulb.

The picaxe is a lot more limited than the Arduino and this may or may not affect the ability to do a program like this. I calculated the root mean square voltage value every cycle at 240hz with 32 bit arithmetic, the picaxe has much lower performance, but would probably suffice for this application.

You can vary the voltage with a 555, this circuit is a led dimmer with a 555.

ne555-pwm-dimmer-circuit.gif
 
amberwolf said:
It would be more complicated and not as physically small as an MCU, but you could use op-amps to control the 555, using feeback from the current thru the bulb and/or voltage across it. Might even be able to do it using just transistors, but I'm not enough of an engineer to figure that kind of circuitry out anytime soon. :/

Yes, you are right. We looked into that, and you can regulate RMS with analog but involves squaring and averaging which is harder to do in analog. Easy to do in a microprocessor under $1 (if one knows how to write the software). The analog equivalent takes a lot more parts, cost and space. One of the design criterion was to fit it in a small volume to fit inside the flashlight switch volume.
 
crea2k said:
Alan B said:
The chip I used was the ATTiny45, which is a smaller flash version of the ATTiny85 which is sometimes used to run a subset of Arduino. It runs at 8 million instructions per second.

You can use a 555 to generate fixed PWM which would work for a fixed voltage reduction ratio, but you will need something like a micro to do the RMS calculation if you want regulated voltage on the bulb.

The picaxe is a lot more limited than the Arduino and this may or may not affect the ability to do a program like this. I calculated the root mean square voltage value every cycle at 240hz with 32 bit arithmetic, the picaxe has much lower performance, but would probably suffice for this application.

You can vary the voltage with a 555, this circuit is a led dimmer with a 555.


Yes, that should work, but it is more hardware than using a micro, and it won't automatically ramp and regulate. If you are content with a fixed reduction ratio and no soft-start it is workable. You won't need the diode with the low inductance of a filament load, if you want to save a component.
 
I think I have a working solution for making a clean beam cut-off at the appropriate height.

Take an illuminated 5mm led, lay it upon a mirror, then look at the wall.

I have ordered far too many led's and some plastic safety mirror to continue with this. I found the closer you got the led to the reflective surface the better. The width of the glass I used was almost a problem. A dimension missing from safety mirror. I may even file the leds, and edge mounting is definitely on the cards. The better the alignment, the shorter the mirror required.

This is very different to what I set out to do. A little disco-ball mirror and a blob of red silicone sealant might be all you need to stop sky writing and start putting all your light on the ground. This mod is so good I should name it lol
 
Finished fitting some of my DIY lights that disguise themselves as reflectors. They have a nice retro look about them.
 

Attachments

  • image.jpg
    image.jpg
    49.2 KB · Views: 1,137
  • image.jpg
    image.jpg
    69 KB · Views: 2,544
  • image.jpg
    image.jpg
    81.9 KB · Views: 2,544
Forgot to show the workings. I used a 9v Nimh battery, switch and a flasher circuit borrowed from some LED strip lights.
The flasher is optional. I used a 9v battery so an alkaline could be substituted. I can also use it on a regular pushy.
The box is small enough to fit anywhere on the bike. I used JST RC connectors since the are very reliable cheap and I have a plenty. So far I have run for an hour and a half and still running happily on one charge.
 

Attachments

  • image.jpg
    image.jpg
    113.6 KB · Views: 2,540
  • image.jpg
    image.jpg
    80.3 KB · Views: 1,137
  • image.jpg
    image.jpg
    61.7 KB · Views: 1,137
A bit of update; connected the second lamp as seen on previous page, worked for less then 10minutes on low beam, then died - led is burnt.
Still waiting to hear cal3thousand and his experiences.

In the meantime I ordered and tested a pretty cheap (4,30eur incl shipping) 12-80v 5w led lamp from ebay, and I m pretty impressed. I had to make my own holding bracket for it, so it holds tight, but the light angle is much wider than the dead one, altho its not so bright, but enough for my night cycling needs.
I also sealed it a bit, so its 100percent waterproof. It doesnt heats as the previous one, and I have a feeling, this one will last for some time (*knock*knock*).
Here it is:
$_12.JPG
$_12.JPG
 
Finished my build.
Here is the plan. Contrast is terrible, but look at the skirting. That's led light not grubby room light
file.php

Here we have a spot light with the upper half reflected down. It's mounted 4 foot above ground. Again poor contrast
file.php

And a flood light centered down the right so you can see the top and side cut-off
file.php


I may of tipped the mirror too low. Putting a bit much on the ground just ahead, not in the distance. I had no blutack to try different angles, but could see lower than other trials was loosing a deficit near the horizon. So I glued it a bit wrong... I might take a marker to the mirror right by the led, where the mirror only serves to reflect near-field light.

My mirror is a bit from a petrol forecourt. Wing mirror I guess. Seems very thin, and although I didn't use it, from one side it is a first surface mirror. Perhaps mylar coated. I hope it don't melt..
It was very easy to grind the mirror with a little rotary tool. Just enough to wear the surface. Then nibble away to the line with pliers
 
toshy said:
A bit of update; connected the second lamp as seen on previous page, worked for less then 10minutes on low beam, then died - led is burnt.
Still waiting to hear cal3thousand and his experiences.

In the meantime I ordered and tested a pretty cheap (4,30eur incl shipping) 12-80v 5w led lamp from ebay, and I m pretty impressed. I had to make my own holding bracket for it, so it holds tight, but the light angle is much wider than the dead one, altho its not so bright, but enough for my night cycling needs.
I also sealed it a bit, so its 100percent waterproof. It doesnt heats as the previous one, and I have a feeling, this one will last for some time (*knock*knock*).
Here it is:
$_12.JPG
$_12.JPG

As cheesy as they are I'm a fan of these too. 'Added wire grommet on the bottom and bit of tubing over the pinch bolt and they're holding up nicely.
 
I have them to. I couldn't get any photo's though, they're too weak. Car sized spot at 100m I would say. Enough spill for 20.

When out carrying my pack and light to test, I got stopped by security lol
He had a bigger one than me, but only flashed it. He wouldn't let me have a proper look. It's surprising what goes off on dark canal paths.
 
Ykick said:
toshy said:
A bit of update; connected the second lamp as seen on previous page, worked for less then 10minutes on low beam, then died - led is burnt.
Still waiting to hear cal3thousand and his experiences.

In the meantime I ordered and tested a pretty cheap (4,30eur incl shipping) 12-80v 5w led lamp from ebay, and I m pretty impressed. I had to make my own holding bracket for it, so it holds tight, but the light angle is much wider than the dead one, altho its not so bright, but enough for my night cycling needs.
I also sealed it a bit, so its 100percent waterproof. It doesnt heats as the previous one, and I have a feeling, this one will last for some time (*knock*knock*).
Here it is:
$_12.JPG
$_12.JPG

As cheesy as they are I'm a fan of these too. 'Added wire grommet on the bottom and bit of tubing over the pinch bolt and they're holding up nicely.

I have one of these and surprisingly the reflector and led are quite good nut the housing is crappy. Mine has paint missing in areas. I may use the guts of this one in an old chrome Dynamo style retro light.
 
I run 2 Cree XML t6 using 2 9v 2a wall warts, which work as dc to dc converters, then hooked up to my CA's aux power output. Works great on my 30s lipo bike.

front view.jpg
 
I have now modded one as a rear light.

In the day, It is mirrored when viewed straight on.
bbb.JPG
As you move round it flicks to a deep red when light can get to the reflector. Mostly it looks alien though. Like somebody has photo-shopped it.
aaa.JPG

Red from behind
eee.JPG
Peachy ay 45 degree's
ddd.JPG
White from the side.
ccc.JPG

And when it matters
fff.JPG
ggg.JPG



Good, bad or indifferent?
I also have a red reflector that sits over nicely. It had a white backing I had to remove. Now it gets a mirrored backing so catches the light more. When switched on it really lights up nicely. The edge of the glass is still visible and gives a nice halo effect the camera won't detect. There is too much glare.
 
Thats the one I bought off ebay as well. It hasnt arrived yet, hopefully another week.
My Princess Auto lights seems decent, I have the strip Unibond light made of real metal its a spot and flood in one, no switch, and 2 sealed auto lights. Initial trials shows they are all good, low amp draw, I might go head and funnel the sealed headlight somehow.
 
those are my new headlight. one i flood and the other beam. i haven't tested outside, as i'm still routing the wires.
but the light are really tiny. they take around 9w from the powersupply each, so it seems the drivers can provide nearly full current to the leds.

IMG_0574.JPG
the lights got color removed and the alloy heatsink was polished to shine.
these are the lights:
https://www.fasttech.com/p/1566300
https://www.fasttech.com/p/1566301
 
I havent tried one of these, but it uses a very bright T6 Cree emitter. I prefer drawing power from the E-bikes main battery pack, but if you dont mind charging the two 18650's separately...here's a unit that can be mounted on your helmet, or...it wouldnt be hard to devise a handlebar mount for it. not bad for $22

I've been searching "18650 cree T6"

http://www.ebay.com/itm/5000lm-CREE...4&pid=100005&rk=2&rkt=6&sd=380984586754&rt=nc

And here's one that will keep your smart-phone charged, if you are using it for GPS/etc

http://www.ebay.com/itm/1800LM-Zoom...8643084?pt=US_Flashlights&hash=item3a9806268c
 
I have been selling this one in my shop for a month, http://www.techbrands.com/store/product/st3467.aspx
It has a 4 cell lithium battery pack in a small bag which attaches to the frame with Velcro straps, 7.2v. The light attaches with rubber o rings as straps.
I sold one to a guy who wanted more light on his moto cross bike. It's pretty impressive.

Before you show a link to an ebay one that looks the same at 1/3 rd the price I have it on good authority that the ebay ones don't have the same run time as this one. I have tested it on the bench for 3 hours on the low setting before it cut out.
I am told the ebay one will give you 30 minutes. Cheap batteries no doubt.

If you live on Oz its available from Jaycar stores.
 
Back
Top