BBJJ (Blinky Ball-Jointed Jellyfish)

thingiverse

Sometimes you see a model on thingiverse and just have to put a light (or lights) in it. That was the case with this one. The first time I saw it, I immediately downloaded it, hollowed out the dome and middle sections of the jellyfish, scaled them up as big as I could print them on my trusty printrbot, and started printing. I finished printing and jellyfish assembly on Saturday but have to wait a few more days for the electronics to arrive. It's about 13 inches tall, and there's a video at: https://www.youtube.com/watch?v=M_Wk8TVNJt8 The bottom and tentacles can be found on the original page. All I did was scale them up 1.8x (I think I scaled the tentacle end up more, maybe 2.6x - print one and see if it fits before you print the rest). In fact, print one of each of the ball-joint connecting ones first and test for fit before you print everything. I had to make some minor size tweaks to get them to work on my printer. Print Settings Printer Brand: Printrbot Printer: Simple Black Rafts: Doesn't Matter Supports: Yes Resolution: .2 Infill: 10 Post-Printing Physical assembly: Snap the ball joints together in the obvious fashion. I used a hot-air gun to thermal weld the middle section to the bottom section once all the tentacles were attached. I also welded on the center mast (to hold the electronics) and the latches. Still working on getting the latches just right. I used a hot-air gun and a set of pliers to punch holes for the charging port on the adafruit powerboost 500C and my button. Electronics In this build, I'm using: Adafruit Neopixel ring - 12x5050 RGB - https://www.adafruit.com/products/1643 Adafruit PowerBoost 500 Charger - https://www.adafruit.com/products/1944 Generic 1000mAh LiPo - http://www.ebay.com/itm/361366607971 An arduino nano that I picked up for a couple bucks from Aliexpress - any arduino that will fit should work fine for this. Generic pushbutton A bunch of wires See the breadboard picture for my circuit. I'm monitoring the battery voltage and flashing a warning, then shutting down if the battery gets too low. I also destroyed the power LEDs on both the arudino and the powerboost. Heat them up with a soldering iron and they'll fall off or get brittle. Once brittle, a screwdriver and a little aggression will make the lights stop blinking. I was emboldened by my pile of spare parts. Don't try that if it's your only part. :) Code Arduino code using FastLED is here:https://github.com/bobiam/blinky_jellyfish Pattern can be advanced via serial (send "n" noquotes) or button (interrupt on pin 2). It's relatively trivial to add a serial bluetooth module like the cheap JY-MCU if you want to send patterns from your phone. I was happy with a button, personally. Why is this a Work In Progress? So the biggest reason that this is marked a WIP is that I'm struggling with the main jellyfish dome. Right now, mine's using a combination of the clips I posted, snipped to fit, hot-glued and welded to the dome and body. It's holding, but it isn't great and I don't expect it to survive for long, but I can lift it by the dome without it breaking off, so....we'll see. Things I've tried: Countersinking a nut into the main mast and gluing a bolt to the top of the inside of the jellyfish - too much stress, failed. Using an assortment of clips to try to make simple closures inside the jellyfish - so far they're all breaking off doublesided tape - ugly and not strong enough Things I plan to try: velcro fishing line (down to the middle section and up through a hole in the dome) posting it on thingiverse and hoping someone comes up with something better? Also, lots of hacking with a heat gun If I were going to make another one, I might try it the same way. If I were going to make a few more, I'd update the 3d models. There's a lot of hotglue, heatgun, and "close enough" going on in this build. It's not something that should be started lightly. You won't take this model, print it, and snap it together. Expect to do some heavy modifications to the parts after you print them.