Ok ladies and gentlemen. Today I got the first test of this year’s Burning Man piece going…
We’re making LED double pendulums! And calling it “Interdependulum” since we’re planning on having more than one.
Each arm has an mpu6050 imu giving us the angle of the arm to the ground and we have acceleration and speed values too. The arms are each controlled by an esp8266 so we’re making a small wifi network from all these moving pieces to have them somehow interdependent.
Now the mechanical and electrical parts are done (at least for the first unit!) It’s time to start hammering away at making some animations and interactivity now. Any suggestions?
Not sure yet. Still waiting to hear back from the artery. I’m kind of hoping to put it out in the deep, it’s not really suitable for a really rowdy area I think.
Do you get the right angles? There are too many forces.
A (potentiometer) rotary encoder may work better, although I suppose it will increase some friction
The angles are not bad. They lag a little when it’s moving very fast and I think it can occasionally lose calibration but I haven’t played enough with it yet to know for sure.
Yeah I wanted to keep it as low friction as possible, so have avoided slip rings or potentiometers. A rotary optical encoder was an option but still created more complexity and wouldn’t have held up well to the dust at burning man anyway.
@Jesus_Vicente sadly there will be no wall behind it at Burning Man because honestly i don’t think I can build a solid enough wall with the resource I have. It will be mounted on a 5ft steel fence post and screwed into the ground with lag screws and tensioned with a bunch of guy lines. Tested this out at a local camp ground and it seemed to work ok.
Lasers are a great idea! Though there are restrictions on those at BM these days.
Hi wonderful work you’ve done. As a animation proposition I recommend use some fire / heat palettes for the pendulum ends - try achieve some of the effects in the video bellow. Also on the pendulum stick could animate some twinkles again with fire palette ( something like sparkling ) If all of this mapped to angle/acceleration will be great ! - https://www.youtube.com/watch?v=ccMoo5hTM3U
@Justin_Eastman I didn’t use slip rings in the end because I wanted to avoid any friction at all. Instead I used inductive power, like you get in your electric toothbrush charger! I picked a few modules off of AliExpress, they have a few different sizes depending on your power budget.
Each arm is independent, but i’m running ESP8266 inside each arm and then will be writing code this weekend to synchronize them. I may just stream pixel data from one arm to the other to make this easier, or i may just emit state packets which each chip then uses to determine what to do.
@Ben_Delarre Great solution! Any chance you can share the link to those parts? Did you have to modify them or is it just plug in the 5v on one ring and receive it on the other?
The first one I used I tried to drive the LEDs at full brightness and it melted the receiver pcb, blew a cap, and I had smoke pouring out of the pendulum. So use with caution. I think the lower amperage ones you can find on amazon and elsewhere are probably more reliable.