One of my follower messaged me asking for some help to create the tail lights for his trike. He build his bike from scratch and at the final stage needs the tail lights that can function as Brake, Reverse and also Indicator lights.
Long story short, he purchased a few Brake and indicator lights but none of them is working to his satisfaction and will not make his trike compliance in the UK.
After a few exchange of messages, what he need is 3 segments of lights, one as Brake, one for Reverse and one of the indicator. So I sketched the rough proof of concept and show it to him.
Then he posted me some photos of his trike, it looks quite amazing, since he build this from scratch.
So the challenge now is whether I can drive the lights just from one strip and divide this into 3 segments, one for the Brake, one for the reverse and one for the Indicator. After tinkering with the code, I manage to get this done and you can see the first version of the lights in the following video.
So I compared with the photos of the location of the Indicator lights. I feel it might not be appropriate to have the running lights for the indicator, perhaps blinking would be more appropriate. So comes the second version of the code with blinking indicator lights instead of the running indicator lights.
Then I have a quick discussion with him over zoom, and he still prefer the indicator lights to be running instead of blinking. So I will need to change the way the lights work. Here is the next iteration of the design.
Because of the shape of the back lights, if we still want to have the indicator lights running to one direction instead of blinking, then we need to use the bottom lights. So here is the next iteration of the demo.
Now you might have noticed that when the reverse light is on and at the same time the indicator is also on. The indicator lights (yellow) will run over the white reverse light. So this might not be the desired outcome for getting the lights compliant. So I made another modification to turn the reverse light off on the side that you are indicating.
Here are the final circuit for the Brake and Indicator lights using WS2811.
If you get to this far, I am assuming that you are interested in the build. Please let me know if you would like to have access to the source code. I haven’t had the chance to post the source code. Feel free to comments or made some suggestions.