Sunday, January 27, 2019

Pixel Cane



After enjoying an old music video of "Puttin On The Ritz", I wanted to build a cane like this for my light show.

This was further driven by this last years "xLights Around The World" where we used "The Greatest Show".

I did an indoor show for my local church, and I thought it would have been really cool to be dressed like PT Barnum with a light up cane sync'd to the show. This is my design process.



I first tried the ESPixel board system, but was not impressed with the flimsy design of the WiFi board on top. I found another take on the same board with a better design, and bought a few.

https://jboards.ecwid.com/ESPixNode-p127558674

This design arrives prebuilt for $13, and has a USB port for easy programming using the same firmware (No other adaptors needed). The only issue I have, I want my design to be fully self contained to run 5v pixels using lithium batteries. This means I need a regulator for the pixels that this board does not have (only one for the control board). What it does have, is a fuse port for the pixels which happens to be perfect for putting on a 5v regulator, and running the ground wire to the bottom of the board. I am hoping that Jeremy sees this design approach, and adds a 5V regulator to the free space on his board for future versions.
I opted for WS2812 pixels, as I would have more granular control of the lights, but would require a 5v bus. Originally I was going for 4 AA batteries, but discovered 18650 Lithium batteries to be a better solution because it would be more power, less weight, and the topper part of the cane holding everything would not have to be as tall. I tried to keep this design as simple as possible, while still protecting everything.

I designed enough room to hold 2 of the 18650 batteries, the ESP board, the wiring above the board, and even a part on the case to hold a power switch.

This whole design is based on some of my work with pixels inside PEX tubing. Due to the design of this, I didn't want one side to have less light, so I double-stuck the pixel strips to each other inside the tube.

This was done in a Zig-Zag, as testing with both strips plugged in yielded no data to the pixels at all.

It was for the better anyways.

Before wrapping the pixel strips, I added a pixel LED to the tip (also called a "NeoPixel", basically another WS2812 but with 2 colors flipped which can be fixed in xLights)

This was difficult to keep the pins from shorting anything out. Once I got everything running where I wanted, I sealed the pins with hot glue.

Next, I designed a part to hold the LED bulb, the Pixel Strips, and lock into the PEX tube at the base. I printed in clear PETG, allowing the single LED to also illuminate the end cap. This will allow for creative pointing at the audience with light.

I quickly realized it was nearly impossible to keep the pixel strip from resting up against the side of the PEX tube. Tensioning the pixel strips was not a good idea, nor possible for very long with this design either. I created very thin stabilizer disks to hold the pixels in place, and you can barely tell they are there when using transparent plastic placed between the pixels.



Not as interesting, but quite important is the lid. I have the battery jumper to get the voltage I need. I printed this in transparent PETG as well so when the unit is powered on, I can see the power light from the board inside the lid. It is not all that bright, to it will not be noticeable to the audience unless it is completely dark and my hand is not on the top.






This is what the final design looks like that I 3D printed. I am working to improve the design a bit more to improve the printing process.