Another triple 35mm from scratch

[mare969]

I am following CFP for a while (few years) and now I would like to introduce myself. I started with my first triple LED lamp about 2 years ago. It was just an experiment with seoul P2 and some DC/DC converter from MPS. After that I started with ONS NCP3065 and other experiments, including new lathe, scratch built CNC mill machine etc... All of the sudden, my garage was full of strange machines and components stock went beyond reasonable hobby limits.

Here's one of my final lamp designs.

I changed from fragile khatod optics to fraen, which is assembled within more durable plastic holder. Complete lamp consist of Alu clad (triple 35mm), heat sink, housing, lense, front glass and mounting holder.

All parts can be produced with hobby CNC mill and mini lathe. I think it could be done at very low cost and with simple tooling.

Another story is supply for the lamp. I used NCP3065 for start, just added one cypress PSoC (with capsense in mind) to control with PWM and measure battery with internal ADC. There are enough pins to drive simple 2x8 LCD or several LEDs. There is some free memory available for additional options, like I2C battery fuel gauge and/or LED temperature sensor etc...

I made also some prototype charger for 2S Li-xx cells to finalize scratch built DIY lamp.

If anyone interested, I could make presented lamp an open-source/open-hardware project.

Regards,
Marko

 

[greenLED]

:welcome:

Way to break out of lurking, Marko!! That headlamp :rock:

You built your own boards AND machined everything too? :wow:

 

[12Johnny]

Wow!!! I wish I had the knowledge and tools to do things like these... Congratulations!! :twothumbs :twothumbs :twothumbs

And of course, :welcome:

 

[HEY HEY ITS HENDO]

Very neat!! ......:welcome:

 

[mare969]

Hi!

I have finalised the lamp design. Now it's waterproof and can be dismounted. It can be simply modified to double (6 LED) or triple (9 LED) lamp. Here's single lamp, assembled:

and double lamp in pieces:

There's also modification in driver electronics, batteries, charger, LiPo protection... My final setup is:

- two cell 4500mAh LiPo battery pack with fuel gauge and protection
- single electronic circuit with small LCD, two buttons, charger, buck/boost driver for LEDs
- single or double LED headlamp

Everything was designed, and developed (hardware and software) in long evenings in about two years... Now I am playing with software. One interesting feature crossed my mind: instead of adjusting lamp intensity I made it "remaining-time" adjustment. Since I am using this lamp mostly for mountainbiking, it's useful to set some minimal output for ascents, but when I reach the top of the night tour, I know aproximately how long is to reach home. Then I simply say to my lamp: "Make my ride as bright as possible for next 45 minutes" I haven't seen such feature with other home made lamps. It's very acurate, since I am using fuel gauge circuit with the battery.

Here's discharge diagram for constant current discharge at 3,5 amps:

The battery pack was 2S EEMB LP7545135.

Marko

 

[Gunner12]

Looks nice!

I'm glad you finished this project.

Which LEDs are you using?

 

[Morelite]

The footprint on the board looks to be for SSC Px's or LuxIII's.

 

[clg0159]

Nice build! any chance of some outdoor beamshots?

 

[BillyNoMates]

Good work, an impressive build with plenty of hi-tec features.

I like the idea of your "remaining time" feature. As long as the fuel-gauge provides accurate estimates of the remaining capacity this would be quite useful - after all there is no point in building a bright light if it is always used at a reduced setting to preserve the battery !! Some way of selecting the "run-time" would be essential I think.

In my designs I simply switch to minimum setting when the voltage drops too low (usually just before the low-voltage knee in the discharge curve). I guess your feature would also run to a similar cut-off point so there is some capacity left for "limp-home" mode in case the battery capacity is reduced for some reason (cold, for example).

 

[mare969]

The saga continues. I made complete ligting system from scratch, own electronics, battery pack, charger, lamp, helmet holder. Everything. It's kind of heretic job these days with ultra low priced and relatively good quality lamps from China. But the wise man once said it's the journey what is important, not the final line. For me, the challenge was the development of useful biking lamp from scratch.

There were so many hours spent with lathe

and with soldering iron

...with my CNC machine

I spent many hours with microcontroller programming

and with modeling in solidworks

...even with sewing machine

and finally, here's finished lamp:

The controller has small LCD with all neccessary info (% of the remainig battery, remainig time in HH:MM, % of output power and time to full when charging). There's a charger in same module. Only 12 external power supply or car battery supply is needed to charge the batteries. The pack has two 4700mAh LiPo cells with protection and fuel gauge.

There are many details about the design and I would like to ask if someone is interested, I could post the whole project as "open source". :twothumbs

Regards,
Marko

 

[wquiles]

Man, that was awesome!!!

 

[Linger]

Well done!:thumbsup:
Stock bike lights are deficient in many ways. The ride time remaining is a stunning idea for max lighting.
You'd probably have a number of buyers if you put out production units.

 

[Aircraft800]

Wow! I never thought this thread would come back! Looks like you have been really busy! Awesome work! Great idea with the lipo meter.