Let’s try something a little different for the tentacle design. With lines this short, there should be no way for us to get SPI interference! Of course, the lines to the LEDs will be pretty long; we’ll have to see if that comes back to bite us 🙄
Oh, the missing pin on the connector is for 12v power to the LEDs. It’ll go in a little later 😉
Perhaps you’re curious why there haven’t been updates for a little while? To make a long story short, our second jellyfish’s circuitry didn’t work. The new radio link allowed us to push color and brightness updates to the lights much faster than the old system did, and the techniques we’d used to construct the first jellyfish simply weren’t able to handle the increased speed. After much panic and confusion, we bought an oscilloscope.
This is an indispensable piece of equipment when you’re dealing with communications interference! With the oscilloscope (and the help of several people far more savvy than us when it comes to RF circuit design), we finally got things working again:
While we were waiting for the oscilloscope to arrive, we’ve mostly finished the gown costume and the skirt/vest costume – and they look great! When we get more of the props integrated, there will be photos.
Progress on Jellyfish #2 is going nicely. The strips for the top half are almost done, and the radio link is working (but still needs to be properly programmed). 500 more LEDs arrived today from China for the tentacles; we’ve decided to add another 24 RGB-controlled segments to each umbrella instead of just using solid-color tentacles. Yay, more soldering…
It lives!
Check out all those beautiful, straight, smooth swaths of wire! Gorgeous, right? It took dozens of tedious hours to make.
One problem. Data apparently goes through them at 2MHz, which means they’re basically turned into radio antennae – and since they’re all nice and parallel, there’s more “interference” than there is “signal”.
The poor umbrella flashes and flickers in a manner best described as “grand mal”, no matter what it’s supposed to do. It’s time to rip out all that beautiful cabling and replace it with twisted-pair wire (and add terminating resistors). Sigh.
No more prototypes; this is the real thing. Each jellyfish will have eight of these strips, with each segment individually controlled. Yep, the soldering’s pretty ugly, but it works!
The second reactor’s internals are done, and I’ve added the spinny-bits to the motor’s drive hub. Now all that’s left is a paint job! We may end up re-working the insides of the first reactor, as we came up with some cleaner wiring and three-dimensional tricks for the transistor clusters. The battery door actually closes on this reactor, and I really want that to work on the first reactor, too…
With some airbrushing, stencils, and “artificial distressing”, these emptied and cleaned CO2 bottles will make great little Helium-3 fuel canisters for our reactors.
Just finished assembling the first segment prototype for the jellyfish! The good news: we can apparently run the WS2801 chips with 12v LED series, so we don’t have to buy (and solder) 150 transistors like we feared. Each umbrella will have 24 of these segments for a whopping 211,000mcd of light.
The LED drivers for the jellyfish arrived today, as did the new linear servos for the butterflies
