The other two dragons are at 200% scale. At that size, they're 46cm long with a 50cm wingspan (18 and 19.6 inches).

The big ones' wings are a single layer thick. The flyer's wings are transparent PCTG; you can see light through them in some of the photos.

I've been on a dual color filament kick lately. The #SoulCage used dual color, and I used three different dual-color PLAs in the dragons, plus a fourth in that crystal cylinder thing one dragon is perched on.

🧵 4/N

#3DPrinting

I know I said the Soul Cage was complete, but I had this idea. The video streams are low speed: 7.5 FPS. The ESP32 has enough bandwidth (I think) to linearly interpolate between frames. Here's an animated file that shows the original on the left and interpolated frames on the right. The difference is much less than I expected.

(I hope Mastodon doesn't mangle the video...)

🧵 21/N

#SoulCage #ESP32

I pronounce the Soul Cage project complete. And it's not even Halloween yet. Its public debut is this Sunday.

I've refactored the firmware from a big ball of mud into something I'm fairly proud of. And I still like the printed case.

Link-o-rama (all repeats):
https://github.com/kbob/SoulCage-Firmware
https://www.printables.com/model/1442110-chain-wrapped-housing-for-soulcage
https://hackaday.com/2025/09/25/trapped-soul-in-time-for-halloween/
https://www.instructables.com/SoulCage-the-Digital-Trapped-Soul-Pendant/

🧵 20/N

#SoulCage #ESP32 #3DPrinting #Halloween

For perfectly valid debugging reasons, I sped up the SoulCage's screen flicker and the soul switching 50✕. This version has a certain frantic panic.

(Yes, this is a different dev board. SoulCage builds for two boards now.)

🧵 19/N

#SoulCage #ESP32

We can do this the easy way or -- aw, heck. Let's just do it the hard way.

🧵 18/N

#SoulCage #ESP32 #OldSchoolUnix

I'm back to benchmarking memory-to-memory copy for the Soul Cage. There are three kinds of memory on the chip: SRAM, PSRAM, and flash. And I tried good old memcpy, ESP-IDF's DMA-based memcpy, and a memcpy that uses the vector registers for 16 byte loads and stores (called DSP copy in the results).

I am copying video off the flash at less than 8 FPS. So they're all fine.

🧵 17/N

#SoulCage #ESP32

The firmware is very rough, but it's on Github, along with prebuilt binaries if you want to build your own.
https://github.com/kbob/SoulCage-Firmware

As the Sirius Cybernetics Corporation's products all say, Share and enjoy!

🧵 16/N

#SoulCage #ESP32

Here's the AMAD soul.

I'll get the firmware up on Github shortly. I'm a ittle burnt out after working on this all night and day. (And more than a little euphoric at how well it came out.)

🧵 15/N

#SoulCage #Halloween #ESP32 #3DPrinting

Hooray! The new firmware is functional! I am very happy with how this came out. I think that giving short glimpses into the video sustains interest, if your attention span is long enough.

There are two souls in the cage. This one is AFAD. (assigned female at death)

🧵 14/N

#SoulCage #Halloween #ESP32 #3DPrinting

I published the housing to Printables and entered it in their Halloween contest. It's still running the original firmware.

https://www.printables.com/model/1442110-chain-wrapped-housing-for-soulcage

🧵 13/N

#SoulCage #Printables #3DPrinting