Police Lightbar Work


claymore1977

claymore1977

Espee Fan
Ladies and Gents,
I've been working on several animation based programs for the Texas Instruments Launchpad (like a cheaper, less featureful Arduino). My current project (and seemingly obsession) is to model a modern day LED police lightbar. I started in 1:24 scale for my proof of concept (learning, coding, wiring, etc) and plan on scaling it down step by step until I hit 1:160.

I have a blog going about the light bar here: http://therustyspike.com/2013/05/16/update01-whelen-lightbar/

I don't know what the general atmosphere on this forum for posting links that takes traffic to an external site, but if I erred then someone please correct me.

That blog post is a bit old, so here is a 'Tech Demo' of the most recent progress: (Note: Shaky hand cam, iPhone quality. Was a spur of the moment decision to take a video)

[video=vimeo;67458642]http://vimeo.com/67458642[/video]

Currently, the $2.50 chip (TI's MSP430G2553) that drives this circuit supports the following features:
-6 Red, 6 Blue, 3 white lights on the bar, all independently controlled.
-2 headlamps, 2 Tail Lamps, all independently controlled.
-IR control, pushbutton backup
-25 bar flash patterns, but the chip has room for up to 180.
-35 hours continuous run time on two AAA batteries.

I have heard of people messing with the Arduino for Model Railroad ends, and figured I'd show everyone a good (read: cheaper) alternative to the Arduino. The programming styles are very similar, so if you learn Arduino, you can program for the Launchpad easily enough.

The thing that made me choose the Launchpad over the Arduino was the fact that you can run a launchpad chip off of as little as 2Vdc. Perfect for battery applications in small places.

My Personal blog is here: http://therustyspike.com/

but I am also part of a 'Crowd-Source' initiative to bring inexpensive and easy to make electronic DIY solutions to the hobby. The blog for 'Launchpad for Model railroading' is here: http://launchpad4mrr.blogspot.com/

Thanks for reading!
 
Thanks Ike, it's been a blast working on this project. And yeah, 1:160 is going to be a challenge. I've got 1:43 and 1:64 prototypes in the works, those are going to be nice. 1:87 will be fun, and 1:160 won't be prototypical sized simply because they don't make LEDs as small as 2 n scale inches :/
 
Completion: 1:24 Model of a Whelen Liberty Lightbar

lp4mrr-300x107.png
And that's a wrap. Well, almost. I need to bump up the amplification on the headlights and decal the model, but other than that, it is finished! The entire point of the exercise was a proof of concept on an accurate modern emergency vehicle lightbar, and boy oh boy did I learn a lot along the way. I'll list those things after the video.

As the prototype of what is sure to be many incarnations to come, I dub this '07 Ford Shelby GT500 my 'Demonstrator'! Please ignore the 8xAA battery pack on the side. Normally, this car can be powered by a 9V that fits nicely into the engine compartment, but I was plumb out of 9V batteries. Yes, there's some in the house smoke detectors, but Murphey's Laws have taught me a thing or two, so I left those 9Vs where they were :) Anyways, using a 8xAA power supply tested the circuitry against a 12V source, so it's all good! Enjoy:



[video=vimeo;69395089]http://vimeo.com/69395089[/video]

Next step: 1/43 then 1/64
Read more at TheRustySpike.com
 
I'll continue in this thread since I don't feel like cluttering up the forum with my projects :)

During the warm summer months, I've been amiss with keeping up with my Model Railroading hobby. But, with the beautiful weather we've had this year, I'm sure most will understand my choosing to be outside.

I have been able to dedicate the occasion hour or two towards miniaturizing Emergency Vehicle lighting systems. While I haven't quite achieved my 1:160 goal, I have accomplished 1:43. The model I chose for my O Scale endeavor was a simple $5 Ambulance toy I found at my LHS. I measured the toy and compared it to measurements I found online and, as near as I can estimate, the Ambulance is right at 1:43.

Starting with the code I used in my GT500 project, I was able to simplify and adapt it easily for use in an Ambulance model. I ordered and used 1206 and 0805 SMD LEDs. Before getting into details, here's the video:

[video=vimeo;76918961]http://vimeo.com/76918961[/video]

Full write up and more pictures at: http://therustyspike.com/2013/10/14/143-ambulance-project/
 
Have you considered using fiber optics? I needed a tiny light source for my Pioneer Zephyr headlight. I located the LED at the back end of the loco and used a fiber optic to send the light thru tight spaces to where the headlight spot is. I heated the end of the fiber optic (a type-of plastic, not glass) to form a bulb end on the fiber optic. I see no reason why one could not locate the electronics & LED light sources under the road or in a nearby structure. One single Red, white and blue led could each feed multiple fiber optic cables to the vehicle where needed.

I found fiber optic cables in a variety of sizes on eBay inexpensive and very easy to work with. Working with multiple colors & suggest you plan it so all white light cables are bundled together and painted (black) to prevent/reduce bleeding likewise with bundles of red or blue. As I noted a single LED can feed/light a number of fiber optic cables.

Heck one might even be able to do a Z scale vehicle that way.

JD
 
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Very cool and great effects!
I was thinking fiber optics also, I scored a huge box of it when a local Radio Shack closed some time ago.
 
For my Zephyr I used a 1.0mm fiber optic. By heating the end (w/a lighter, does not take much) it formed a lens about double the diameter of the fiber optic cable. I took only 2 tries to get the lens like I wanted. One can practice/ experiment with a F/O end, then when its formed the way you want or need, then feed it thru the itsey bitsey hole and then cut to desired length. While I used a very tiny bright white LED even it was no where near small enough to fit in the available space.

BTW my N-scale Zephyr is a 30 +/- yr old resin DIY kit. I had to drill my own hole even there is basic circuitry (PC board floors for coach lighting, there was no provision for a working headlight.
 
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