This is a project similar to the one already published, but upgraded. It consists of 64 LEDs and 90 columns, so the resolution is 5760 pixels.
I also used the shift registers, but 8 of them, one for every 8 LEDs. To transfer power to the shaft I used slip ring from the alternator.
The frequency is quite small, about 20 rps, which is about 1200 rpm.
Step 1: Materials
I hope I wont forget something, but everything should be here:
-8 shift registers (74HC595)
-64 220 Ohm resistors
-Slip ring and brushes (from alternator)
-PVC pipe (18cm)
-220V DC motor
-Flat wires (for LEDs)
-Aluminum sheet 2 mm
Step 2: Housing and the Ring
Housing is made from 2x2 cm square metal pipe.
The ring is end piece of PVC pipe, and it have 64 3mm holes for LEDs and two 10mm for shaft.
After painting and drilling i put it all together. On top is metal bearing, and on lower side is conected on the motor.
Step 3: Power, Shift Register and PWM
5V DC power, shift registers and PWM PCBs I made myself in Eagle. Here you have schemes of the circuit.
Step 4: Slip Ring
Slip ring is used for powering the shaft, it's easiest way to do it. Just be careful! It needs to be centered or you'll have breaks in power transfer. Because of this, your Globe won't work, so you'll need to put capacitor as big as you can buy.
Step 5: Putting All Together
Arduino Uno and PCB with shift registers are placed on fiberglass on the shaft. 5V DV power and PWM are in housing. You have only 3 wires from arduino to the shift registers PCB. LEDs and Arduino have the same source od power supply.
Step 6: Program
I just upgraded program that I find on Internet. You can make any picture or write something in few seconds. Pictures have 5 760 pixels(90x64).
Step 7: Final Result
If you have any questions, feel free to ask me on firstname.lastname@example.org
And here is my video on youtube:
Third Prize in the
Maker Olympics Contest 2016