The topic of my final project was the design and construction of an RGB LED globe based on an optical illusion. The essence of this is that the LEDs on a semicircle project a continuous image on a spherical surface due to rotation around one axis. This requires a rotation speed of about 25 rps and to flash the LEDs with millisecond accuracy.
The design of the device consisted of three main parts:
• Mechanical design
• Electrical design
Mechanical design included the design of the support structure, the rotary ring, and also the proper fixing of electrical devices and the supply of power through the bearings.
During the electrical design I figured out the structure of the circuits and made the designs of the printed circuits. After that, the elements were produced, soldered and installed.
The finished hardware can be controlled with three Arduino Nanos. The arrays required for projected picture are generated by another software, in which you can draw the image you want to display.
The end result is a spectacular and educational device that offers many opportunities for improvement.