Well I’m back home after taking the staff out for Halloween. I carried around as part of my costume, costume – greeting people coming to the community for trick or treating, but also to hang out with my neighbors. A lot of people were asking about the staff – both seeing it in action and having heard about me working on it for the last 2-3 months.
Now, I’m back home, the staff is sitting in the corner, still running. I’m using this as a battery test. It’s running the ‘sparkle’ pattern, which everyone agrees is the prettiest (see the video from my previous post). It’s been on, showing patterns and lights now for about 5 hours, easily surpassing what I expected from the 8 C NiMH cells.
People on Hackaday and people I meet in person ask a lot of questions, so I decided to write up an FAQ….
Lets start with the first one… “Why did you build this? Where’d you get the idea?”
It all started with a book…
Stephen Barnes and Larry Niven wrote Dream Park in 1981. It had a tremendous impact on me – live action role playing, with high tech assistance. At the beginning of the story, the characters are getting ready for their game, and Acacia, a new player, is watching a veteran gamer prepare…
She was playing her wizard’s staff while she waited.
That was stunning. Acacia had seen pictures in the Gaming magazines. It was five feet tall and an inch thick, jammed with instrumentation and the internal computer. Patterns of colored lights ran up and down its length, and monochromatic flames lashed from the tip, as Gina’s fingertips ran over the contact-sensitive keyboard.
Tony watched as if mesmerized;
This one simple paragraph stuck with me for years. Wouldn’t it be cool if I could build something like that?
So, finally… I did….
Anyway – on to some build details…
- There are 8 Tenergy NiMH C cell batteries, in 2 groups of 4. They’re about a foot and a half from the top and bottom, to keep things balanced.
- The batteries will run the staff for between 3 and 5 hours, depending on what patterns I’m displaying.
- There are 6 strips of LEDs, each 55 lights long.
- The current microcontroller is an an Arduino Uno R3, which is a ‘prototype’ controller. I’ll replace it with a Micro 05 soon.
- The entire staff, with batteries, is about 75″ high, and weighs around 6.5 pounds
- The LED strips are WS2812 based LED strips from AliExpress, and cost about $37 per 15′. I needed 3 sets, I have about 10′ of strip left over.
- The code that drives it is written in a C variant used on Arduino microcontrollers. It’s about 250 lines, and uses the Adafruit NeoPixel library.
- There are two tubes, made out of extruded acrylic (plexiglass). The inner tube is cut in half lengthwise and holds the batteries and will eventually also contain the microcontroller. The LED strips are mounted on the outside of this tube. The inner tube is 1.5″ outer diameter, with an ID of 1.25″. The second (outer) tube has a 2″ ID and 2.25″ OD. The inner tube rests inside the outer tube and is held in place with end caps made out of wood. The ‘top’ end cap has a conduit cut in it to allow wiring to the controller currently residing in the ‘globe’ at the top.
- The LED strips are secured to the inner tube via hot glue (as were a lot of pieces of this project).
- There are only 2 controls; a power switch and a single push button. The push button generates an interrupt on the controller that tells it to change to the next pattern.
- No, it wasn’t a kit, I didn’t see it posted somewhere else, I didn’t copy someone elses design. This has been my vision, my design, and my build from the beginning. So there.
Am I happy with the end result?