LED Cube
Project originating from ME 318 at Stanford University
The assignment was to design a product of one's own choosing and manufacture it using a CNC vertical mill. This product is a 4x4x4 LED Cube array which has an aluminum chassis. Each LED can be individually turned on and off by the integrated microcontroller. The design is based on multiplexing a common cathode for each layer and selectively supplying a positive voltage to the desired column. One unique aspect about the chassis design is that each layer of the aluminum chassis actually functions as the common cathode. The electrical system features a simple buffer circuit so that the microcontroller is purely used for logic and not current supply to the LED's. While the project was completed for a demo for the class, I am continuing to work on it and make improvements.
Each layer of LED's is a common cathode, as is the respective aluminum plate. The vertical posts are made with off-the-shelf aluminum spacers. In order to insulate the plates and aluminum spacers from each other, custom 3D printed spacers were used. The 3D printed spacers feature bosses which align the plates and aluminum spacers. The entire assembly is held together with 4 long screws.
The common anode of each column is tied together with custom-made wire harnesses.
The anode of each LED is electrically connected, and fastened to the aluminum frame layer using machine screws.
First revision electronics integrated into the base. The protoboard features two buffer IC's and four N-channel MOSFETS to control anodes and cathodes, respectively. The Arduino is held in place with a 3D printed bracket.
I am continuing to make changes to the cube, particularly to its electronics. In order to make prototyping easier and the electronics more modular, all of the cube's electrical connections have been wired to a ribbon cable.