Hello everyone!
This is my first time posting and I have enjoyed scrolling through everyones projects.
I am currently building a concept piece titled “Girl on Fire”.
It is a dress and features:
28 x neopixels (placed on the mid band)
6 x 32 x 8 LED matrices (placed on the front 6 pleats of the skirt)
1 x motion detector.
Raspberry Pi Zero
The idea is that the flames on the dress are activated by 360 degree spin, engulfing the dress in flames. Like the hunger games.
This is my first time working with matrices and given that there is 1564 pixels on the dress I am still learning about appropriate power sources and controllers.
I have bought a re-chargeable battery pack (10000mAh) and raspberry pi zero, although currently my adafruit Flora is controlling just the one matrix whilst I test.
I have only just started playing around with one matrix and tried very briefly to upload an fastLED fire library - However, didn’t play around too much to get my desired effect. Video attached.
I am hoping to get some advice on:
- Mapping the LEDS and what program to use + any helpful tutorials on how to do this.
- Informative tutorials on calculating how much power is required.
- Any advice re: combining sensors with LED’s.
Thank you so much in advance!
Hi
If you’re driving that many WS2812 LEDs then I’d suggest a teensy 3.2 controller. Then you can use parallel output and get a decent frame rate.
The raspberry pi isn’t a supported board, but there is a port for it.
I map LEDs in excel then use a simple visual basic function to build the data for defining the arrays.
As to power, with wearables it all comes down to brightness. I doubt that you’ll ever get near to full brightness, so your power requirements will be much smaller than the theoretical maximum. I use 3300 mah 18650s for mine. But I don’t use many LEDs. You’ll probably just have to experiment and see how long your battery pack lasts…
Good luck
@Jeremy_Spencer Hey Jeremy, thanks for the quick response.
Ok I will look at the teensy controller. I’d rather use supported boards given my baseline knowledge, I’ll try to get everything running as smoothly as I can.
In terms of the “simple basic function to build the data for defining the arrays” are you able to give me an example of what that is composed of?
Yep, you’re correct, I won’t be going anywhere near full brightness (especially because there is 6 panels).
Private Sub Calculate_Matrix_Click()
Dim Matrix As String
Dim x As Integer
Dim y As Integer
Dim count As Integer
Dim ws As Worksheet
Set ws = Sheets(1)
For y = 2 To 93
For x = 2 To 31
If Cells((32 - x), y).Text <> “” Then
Cells(70 + y, count + 1).Value = Cells(32 - x, y).Text
count = count + 1
End If
Next x
count = 0
Next y
For x = 2 To 31
For y = 2 To 93
If Cells((32 - x), y).Text <> “” Then
Cells(70 + x, count + 20).Value = Cells(32 - x, y).Text
count = count + 1
End If
Next y
count = 0
Next x
End Sub
@Jeremy_Spencer Amazing, thank you so much!
Ive been wearing LEDs for the past 6 months. 1/4 of the brightness has always worked well for me indoors
For motion sensing I suggest the MMA8451 or LIS3DH accelerometer breakouts from Adafruit. Cheap and easy to use.
Hi Kiah,
I’m the person who did the Raspberry Pi port. The port currently is pending review for inclusion into the main FastLED repository. I.e. its only available from my account at https://github.com/mikeburg/FastLEDLinux
To echo what other people have said, the Teensy 3.2 would be good fit for what you want to do.
The raspberry pi, while a nice little board with a huge amount of computing punch, is more geared for things that require being always on. The PI takes about a minute to fully boot up and really wants to be shutdown properly otherwise the SD card does run the risk of being corrupted. Its pretty much a small laptop that would like a keyboard and monitor attached to it.
With the Teensy and other boards like the Flora, power can be applied and the thing runs immediately. Power can also be cut any at moment without issue.
Hi Kiah,
Just wanted to share that you can use the tinyTILE which like the teensy is small, runs arduino, but also has the intel curie which has all the accelerometer, gyros, and bluetoooth necessary for your functionality. Its all baked into a nice small board.
I wrote a tool that converts gif animations to arduino sketches that make it a bit easier to design things for whatever grid size you have. Its a lot easier to create gifs than it is to design from scratch!
https://www.element14.com/community/docs/DOC-82913/l/tinytile-intel-curie-module-based-board
@Lloyd_Emelle oh snap! I think i may buy that instead of the teensy for my LED matrix lol
Hi @Kiah_Hickson I’ve been working on wearables for little while too. Definitely recommend the teensy 3.2 and parallel output. You’ll also need a 74HCT245 level shifter btw. For mapping it might be worthwhile to look at @Jason_Coon 's tree v2 project for mapping since it lays out an example of mapping around a cone shape which could translate well around your skirt. There’s also a fire animation.
I’m just finishing up a project now with 1166 LEDs with Teensy 3.2 and parallel output.
@Charity_Stolarz what is that? Looks like a scarf of some sort?
@Cristian_Martinez Amazing thanks for your feedback. It’s good to know what works.
@Franck_Marcotte Hi Frank, thanks for your advice. I currently have the Adafruit FLORA Accelerometer/Compass Sensor - LSM303 - v1.0. Do you think that this one is good enough for what I am trying to achieve? I have used this sensor on my first LED wearable dress and it worked well.
Hi @Michael_Burg ok so it looks like I will be buying a teensy!! Interesting feedback and I am certainly learning a lot from this. I will store my Pi away and use it for another project it seems. Thanks 
Hi @Lloyd_Emelle thank you for bringing the Teensy Tile to light! It sounds amazing and ticks the boxes of everything I want in a controller. Funnily enough I was looking at the intel curie platform on Saturday!
With regards to the tool you built is this open source or available for others to use?
Hi @Charity_Stolarz this is awesome advice. I will be sure to get the level shifter and I’ll check out Jason Coons project. Also awesome that there is a fire animation.
Nice work on your project! That looks really awesome. How did you find working with so many LED’s? Are they on strips/ individual?
Also, another question - How easy or hard is it to combine two different types of leds in the mapping process and the wiring process? I have both neopixels and matrices. I’m curious to know if you have experience combining different types?
