Since Make Munich come closer with giant step,s it is time to build some new exhibits. First test with a taped together ikosahedron where successful, so i wanted to build a more cleaned up version out of spy mirror acrylic for better reflections. On a side project while waiting for the 3D-prints i also built the simple cube version.
A laser cutter is used for cutting both acrylic spy mirrors as well as diffusor plates for the icosahedron and the frame for the cube, while a 3D-printer is used for the frame of the icoshaedron and stands.
WS2812b stripes with an ESP32 as controller are used for enlighting. The cube uses stripes with 60 LEDs/m, the ikosahedron stripes with 144 LEDs/m.
Acrylic spy mirror can eb bought at Pyrasied, a source for all kind of interesting acrylics.
Step 1: 3D-Puzzle
My Icosahedron is made by Triangles of 15 cm length (due to the bed size of the Epilog of 60 cm *30 cm). For connections we use the files from the Icosaeder.scad file: As a parametric design, you can easily change the design for different sizes and types of LED stripes. The connector() -module there shows the clip onsystem for the edges: I divides it into 3 parts for easier printing without any support. Holes on the outer side are used to clip the LEDs as well as the Capacitors next to it on the stripe on the into the design, while the acrylic parts (3mm thick) are clipped on the side.
A diffusor made of 3mm semi transparent acrylic ist plugged on the inside for light guidance (see third image). For stabilization, the 3d prints are glued together on the edges with Epoxy.
Step 2: Wiring
When the ikosahedron is assembled, the LED-stripes are glued on the outside. For easier wiring we start on a corner, go on a zig-zag line around it, afterwards continue with the zigzag in the middle and finishing with the uppermost 5 triangles in one line. In most cases, we can therefore just wire from one strip to the next with silver wire.
This leaves some edges outside this line: Here we go from one stripes date out into this stripe and on its end back on the strip to the start and the zig zag line, fixated with tape.
Directly add the controller at the start and test each assembled strip, since both data direction won't be visible anymore and therefore mounting all stripes before soldering is not recommended.
Step 3: Finishing
For covering the stripes (albait i was tempted to leave stripes and silver wire visible) thin cubes are glued on the LED stripes (the cube() at the end of the part list in OpenScad). The edges are covered with caps, which are bend into shape, and a stand is printed out (socket()).
Since i used a wrong angle for the socket arms, thin stripes of black foam are used as a distance holder (third picture), which gives it a nice floating touch.
The hole on the back of the stand is used to cover the ESP, it uses at the moment just the basic example of the Fast-LED-Library, uploaded with the Arduino IDE, with the Stripes at pin 17, 5V connected to the ESPs 5V, same for Ground.
Step 4: Bonus: Cube
While waiting for the 3D-prints i got bored and build a basic cube with roughly 30cm edge length. First the Stripes in Cube.svg are cut out of 5mm MDF and glued together (both with glue as well as tape for quicker assembly).
The sides are optimized for stripes with 60 LEDs/m, with 60 LEDs glued inside one side of the frame, with 360 LEDs in total, the Ikosahedrons used 630 LEDs.
This stripes are again hold in place with tape wrapped around frame and stripe. Each of the six stripes then got a 4 wire connection (VCC, GND, Data out and in) with flat cable, again hold in place with tape and guided along the frame to one central point used for the stand, where they are connected in a row.
Next, the Cube_Box.svg was designed with CutCAD (i just made the mistake to assume a symmetric setup while cutting the same side over and over again, which leaves mistakes in some edges (luckily, neglectable)). A triangle hole is then made in one corner for wiring, and the acrylic spy mirror sheets taped together.
At the moment i am still undecided to glue it nicer together without the tape or design cover for the edges. They are already included in the icosaeder.scad file, same goes for the stand of the cube, which was printed afterwards.
It uses again a hidden ESP in the socket with the same program as before.
Step 5: Next Steps
it already looks nice, but in the next weeks i need to add some interactivity. One will be made sound reactive, the other probably connected to three heart beat sensor (one for each RGB color). Other options are brain waves, or maybe designing some game on it.
But for the beginning i'm just enjoying the colors.