Opinions/Comments: Custom LED Bike Light...What would you want?

I have been interested in designing a custom LED bike light, that would incorporate one of Lamina's BL3000, with possibly the 60 degree optic on top of that. The only other consideration is a custom reflector.

I have not been able to get a good idea of how much something like this would cost to the end user. But, a single BL3000 is around $80 or so, and I'm guessing custom aircraft aluminum with anodizing would be in the $40 to $80 price range, and then the electronics to drive the LED. I'm assuming the electronics would be the cheapest part.

The battery pack would probably need to be sold with the light, or a rather common connector would have to be used so that people could design their own batteries. I was considering using a battery pack that was off the shelf. I'd like to use a current bike companies' battery pack and charger, but buying those parts from them would be expensive, and probably not in their best interest. The battery pack would probably need to be on the order of a 11.1V Li-Ion, capable of supplying 8-10Ah of capacity.

I would expect a light of this magnitude to cost around $250, by the time everything is done, maybe $300. Keep in mind; this is the light head only, no battery pack or charger included in that price.

The electronics would consist of a constant current driver, with probably a boost type regulator. The Vf of the LED is 11.3V @ 2.3A, and puts out about 567 lumens. The microprocessor would be able to control several brightness levels, to allow for longer run-time, or for less light output when using the light on lighted streets, for example. I would imagine about 4-5 different levels of light. Also, a battery meter feature, that would include a battery level indicator (series of LED's on the back of the light), and a shut-down sequence when the battery gets low.


I'm trying to see if there is any interest in this, as building just 5 of them is rather expensive, but building 100 or more brings the cost down a bit. (Especially with the custom enclosure.)

So, what do you guys think? Based on if you liked the enclosure, and all the features, would you consider this light over one of the leading manufacturer's of HID bike lights, or LED bike lights? This isn't really a reality yet, just an interest of mine. If there is significant interest, I may get pushed more into doing something.

This light should be more than enough for road biking and probably just right for mountain biking. I currently have a Light & Motion ARC Li-Ion, and I'd say it's bright enough for mountain biking, and it claims 675 lumens.

Re: LED Bike Light...Is There Interest?

I have interest, I'm looking for a high output headlamp led. I would be interested on the projected weight of this light.

Thanks Pete

Re: LED Bike Light...Is There Interest?

Weight is an issue, especially doing something custom, as most current manufacturers (most, anyway), are using composite housings made out of injection molded plastic (or composite). So, their weight is reduced quite a bit.

Using aircraft aluminum I think would allow a lighter enclosure, since it's quite a bit stronger than standard aluminum stock. However, I feel the dominating factor in weight, will not be the actual head, but the battery. I think the head can be made small enough (but I just have to provide a reasonable amount of heat sink material for the LED), that it would be acceptable to most people. An 8Ah Li-Ion battery, on the other hand, will be fairly heavy. I have a 4Ah battery, and while it's significantly lighter than its NiMH sibling, it's still a chunk of mass. I think at least an 8Ah battery is needed to provide about 3-3.5 hours of operation.

I was thinking of a black anodizing process, but will have to talk to the person I was thinking of having do the CNC work. I think he has the capability to do HA-II, but not sure about HA-III. In all regards though, if you crash with a light with anodizing, it's not going to matter much, if it's II versus III. It's still going to get scratched pretty badly.

Anyway, seems like a lot of people are reading the post, but only one response so far. That doesn't sound good. The only other avenue I think I would have as far as selling the light, would be to put them out on eBay, but even then, it would probably not get the visibility I would need to sell around 100 or so. I have a domain name, but the problem would be getting traffic to the site. Google doesn't seem to like my current content very well!

Well, after some research, I found out, the 60 degree reflector for the BL3000, is not really a reflector, but an optic. It sits directly on top of the LED array. The interesting thing about this, if it works like a reflector, is that the actual size of the housing could be a LOT less. I mean, we are talking maybe an inch in diameter, if this is the case. The electronics will then be the limiting factor in getting them to fit inside...interesting.

Re: LED Bike Light...Is There Interest?

I am interested, but I need to see pictures and beamshots before I can justify buying something this expensive.

Re: LED Bike Light...Is There Interest?

Noted. I understand compeletely. I plan on getting the LED with optics pretty soon, and then building a circuit around it, for testing. Hopefully, just having this small amount of the project, will allow me to see if it's going to work as a bike light. I plan on doing beam comparisons to the current light I have.

Re: LED Bike Light...Is There Interest?

Why bother with a bike light? You have described much of what I started a thread on a while back.
Just a Light (JAL?) A head unit with a switch, something that would allow a variety of voltage inputs, some regulation and perhaps a few stages of light.
A female socket on the back would allow plugging in a cord that lead to 2AAA batteries or 20 car batteries in parallel. A twist lock would allow attaching a battery pack to make it a flashlight or a mounting bracket to make it a bike light or a head light or a chest light.

Re: LED Bike Light...Is There Interest?

Mike. All very good ideas, that I had not considered. The "everyman's light," in a matter of speaking! That is a perfect idea. In fact, some of the components I was planning on using for the driver circuitry can run anywhere from 3V to something like 18V, and provide a constant current output, with voltages as high as the input.

I could possibly also have a machined body for a series of batteries to be installed, kind of like an M6 or similar. Very interesting.

Thanks for the input. Based on that, it may turn into more than Just a Bike Light.

Re: LED Bike Light...Is There Interest?

I don't know how easy this would be, but another idea might be to find a good modification to existing bike lights rather than create a new one.

Many bike lights use a 6V or 12V Halogen MR11 bulb. They typically are two beam, one wide and one narrow. The narrow beam is 10deg, and the wide beam is 20 or 30deg wide, meaning 60deg on a bike light would be like a flood light.

This way, you only have to come up with a replacement bulb, not a replacement housing. The electronics may be better off in their own housing that could be part of the battery pack, or mounted between the battery and light. From experience, Cygolite has a decent amount of space inside their water-bottle battery that isn't used.

Re: LED Bike Light...Is There Interest?

I like Mikes ideas. I use a twofsih cycloblock for a mount so I can use various 123 lights. If you could make it for various voltage inputs like Mike suggested and hopefully the thing will not be to big, so that I can use the cycloblock. Also I just like the idea of using other manufactures battery packs or make my own.

http://www.nashbar.com/profile.cfm?...rand=&sku=3203&storetype=&estoreid=&pagename=

Re: LED Bike Light...Is There Interest?

One more thing, if you manage the various voltage inputs and a plug/socket in the back. If there is any room in the light. Would it be possible have a self contained battery pack inside like 3 or 4 aa or aaa's. And maybe have a switch between using that or the input plug.

Re: LED Bike Light...Is There Interest?

hookoo said:

One more thing, if you manage the various voltage inputs and a plug/socket in the back. If there is any room in the light. Would it be possible have a self contained battery pack inside like 3 or 4 aa or aaa's. And maybe have a switch between using that or the input plug.

Click to expand...

NO! That defeats the idea.
Having a simple and common means of attatching to the light is what you want. Something that plugs in and twists to lock might do it.
Then you could twist-lock a small minimum pack on the back, a conventional tube, a right angle tube, etc. or just a cord to a larger pack.

Re: LED Bike Light...Is There Interest?

cuervo. Good points. That is something to consider, only the problems comes with the cooling of the LED. A drop-in replacement would have to have some sort of heat sinking, and I'm not sure it would be enough for this thing, at ~26W. The idea I had, was having the housing become the heat sink for the LED, in other words, the LED would have a mounting place, that interfaced with the outside of the enclosure.

I don't know if you guys are familiar with the McLux III PD at all, but I was thinking along the same lines as that, only it would not be epoxied down to the surface, just thermal compound, and screws to hold the LED array in place. The outside of the enclosure would have low profile fins (so as not to be damaged too badly upon impact), to help provide cooling to the LED. I anticipate just the mass of the enclosure would provide enough heat sinking capability, that the fins would just provide a little more help.

hookoo. I think Mike is right, about not putting batteries inside the enclosure. Someone else mentioned this in another thread, and even posted a picture of a drawing of such a light. But the problem is that AAA or AA batteries would provide almost no runtime with this type of light, at least, on high. It would be like having an Orb RAW, in a larger form factor! Keeping the enclosure small is going to be difficult enough, and the intended use for most people, would require an external battery pack. The idea of the twist-lock connector on the rear of the head is a great idea, which would allow people that just wanted to use it as a flashlight, be able to do so, by adding a battery tube or pack.

Re: LED Bike Light...Is There Interest?

Just to summarize so I see whether I have everything in order:

- 60 deg. optic
- high power
- power adjustable for 'on street riding' ?

Maybe for serious offroad/MTB trail riders. For everybody else, not a good idea.

With a 60 deg. opening angle, you're wasting too much light in the close area and get too little where you need it. Upping the power won't help you much since your eyes will accomodate to the high light levels close up.
Especially for street riding, such a light would be worse than useless (IMO), since the most you will achieve is to blind everybody coming the other way, without really lighting up where you're going.

For street riding, you'll need two lights:
- one to light up the street, from (ideally) your front wheel up to ~20m in front, maybe 2..5m to each side, with a constant light level over this area (i.e. the area close to your front wheel shouldn't be brighter than the area 20m ahead...) and next to no spill in upwards direction (you don't want to blind any oncoming traffic - cars, cyclists, pedestrians. Make them notice you, yes - but blinding them will serve the opposite purpose).
- one light to light up everything, as far as possible, if there is no oncoming traffic - but as little light as possible in the close-up region where it would foul your night vision.

Since I do most of my riding on streets (and get seriously annoyed if I'm following a marked path that suddenly loses its paving...), your light wouldn't help me at all.

Bye
Markus

Re: LED Bike Light...Is There Interest?

markus.

It seems you may be right. After a little searching, it appears that most bike lights (although I've found no reference when using LED, just halogen and HID), have 10 degree optics. 60 degrees seems a bit wide for this application.

Unless Lamina comes out with some tighter optics for this particular LED, then it may not do any good to go further with this project.

However, here are some ideas, input solicited.

The BL-4000 (in white, of course), can put out only about 120 lumens. This isn't much better than what is available on the market today. However, Lamina makes optics for these LEDs as well, a narrow beam of 10 degrees, and a medium beam of 30 degrees. I'm wondering if a kind of hybrid light, with a BL-4000 and a 10 degree optic, and a BL-3000 with a 60 degree optic would be suitable. Mountain bike lights generally need to provide a lot of side spill light, in order to see obstacles, but also need to be able to look down trail to pick the best line to follow.

This type of configuration would add almost twice the amount of housing real estate that I was originally wanting, but it may still be fine. Basically, it would be a light in the shape of two 1.5 inch tubes put next to each other, but flat in between them. This would look similar to a rectangle 1.5 inches tall, 3 inches wide (possibly down to 2.5 inches here), with rounded edges. The only problem, is that now the typical flashlight bezel design is out, unless I make the light a 2.5 inch cylinder, which makes the light pretty large.

[Edited]

As far as blinding in the opposite direction, I've noticed this a problem with current designs.

I've noticed that cars typically have some type of shield that blocks off light at a particular angle. While this would be great for street riding, sometimes it's desireable to have this upward going light in mountain biking, for noticing tree branches and what not.

I wonder if some type of shield could be designed to either be manually installed in the light by the user, or some type of external shield that is placed on top of the bezel to cut off the undesired light. It's an idea anyway, but one that I'm sure not everyone wants.

Re: LED Bike Light...Is There Interest?

hi gang,

LED bike lights! One of my favorite subjects!

As much as I encourage people to play around with lights, you should know that Cateye has introduced a couple of rather nice and well designed lights using 3W Luxeons. You can get to the product info here:
http://www.cateye.com/en/products/viewProductModels.php?catId=7&subCatId=1
(sorry about the low-tech link...)

These aren't cheap, which is perhaps a testimony to the materials used in the construction. The housing appears to be an aluminum extrusion, which will provide good heatsinking as well as ruggedness.

Not sure what optics are used. I think I saw a review that said that the beams were not aligned exactly, so as to put a little light close, and a little light further down the road.

All in all, this *may* be the light that many have been waiting for. Now if it was just a lot cheaper.... (I think it retails somewhere around $300).

Steve K.

Re: LED Bike Light...Is There Interest?

Geogecko said:

markus.

....
This type of configuration would add almost twice the amount of housing real estate that I was originally wanting, but it may still be fine. Basically, it would be a light in the shape of two 1.5 inch tubes put next to each other, but flat in between them. This would look similar to a rectangle 1.5 inches tall, 3 inches wide (possibly down to 2.5 inches here), with rounded edges. The only problem, is that now the typical flashlight bezel design is out, unless I make the light a 2.5 inch cylinder, which makes the light pretty large.

[Edited]

As far as blinding in the opposite direction, I've noticed this a problem with current designs.

I've noticed that cars typically have some type of shield that blocks off light at a particular angle. While this would be great for street riding, sometimes it's desireable to have this upward going light in mountain biking, for noticing tree branches and what not.

Click to expand...

...

Before you start re-inventing the wheel, here are two designs that are currently cruising the german mailing lists/forums:
<bugger - how do you do links in this new interface? /bugger>

http://tandem-fahren.de/Mitglieder/Framstag/Luxeon/Delgado/

http://www.mtb-biking.de/lampen/led/ray.htm

I have too little experience in MTB/trail/off-trail riding to comment on the 60 deg light. The first design is intended for road use together with a non-blinding bike light (http://tandem-fahren.de/Mitglieder/Framstag/Luxeon/Larry/ or a standard bike light (in the US, perhaps look up peterwhitecycles.com), the second design (together with its mates) is a pure MTB light with little spill in up/down direction and controlled extension in left/right.

Bye
Markus

Re: LED Bike Light...Is There Interest?

I will suggest that you to a search on "bike light" using any search engine. I did that a few years ago and came up with a plan to make a light out of a black rubber plumbing fitting using a 12V flood light. I built it and am still using this light today. No, it isn't an LED, but it lights up the road like a train! Total cost was around $25 for the light and $15 for the rechargable battery. I keep the battery in a seat post bag.

Re: LED Bike Light...Is There Interest?

What would be the largest diameter bike light that would be acceptable? If I could keep the length on the light down, to say, a couple inches, I'm wondering how large I could make the diameter.

I am working on some different configurations, but unfortunately, the ones I like, end up being fairly large. The determining factor, is trying to use the BL-3000. While it's been stated that the wide optics may be too wide to be able to see down a trail far enough, I think a hybrid light, using some 5W/3W Luxeon's with the BL-3000 could provide an incredible bike light, especially for off-road use.

I've decided that if I were to use the BL-3000, I would go with the 4300K color version, as this seems to be more suitable for color rendition, and depth perception when viewing outdoor terrain, at least, in my opinion. It's lumen spec. is a bit lower, I think 525 lumens, versus 575 lumens for the 5500K color version.

Another aspect of concern here, is that when driven full wide open, the BL-3000 consumes 2.3A at 11.6V. Well, in order to run just two hours, only using the BL-3000, would require a 4.6Ah battery pack. I'm trying to keep the battery requirement down to about 4Ah, because anything much higher than that, starts to get very expensive, at least, when considering Li-Ion's. So, what I was thinking, is driving the BL-3000 at a lower current than the spec. This would allow me some spare room for adding some 3 or 5W LED's, and keep my 4Ah battery pack. Of course, the driver circuit will be capable of driving the BL-3000 at full brightness (2.3A), but I will current limit it (or PWM limit it), so that it does not draw as much current, via the microcontroller. There will have to be some type of configuration mode, so that the brightness can be set, and stored for next use.

Any more opinions?

Re: LED Bike Light...Is There Interest?

http://www.theledlight.com/systemx.html

Re: LED Bike Light...Is There Interest?

hsjrev said:

http://www.theledlight.com/systemx.html

Click to expand...

Cool, one I haven't seen before, but it's still just one Luxeon. I tried a Surefire U2, compared to an HID, and, well, it is still blown out of the water.