Assignment
The name of my final project is “Didactic Crystallography Model”. All the details of the final project, including the idea and the tracking of it so far is documented in the final project page.
It will facilitate the understanding crystal structures. A crystal structure is a three-dimensional arrangement of atoms, ions or molecules.
These are ordered structures that occur due to the nature of the atoms or ions to form a repetitive symmetric pattern. In my case, in the subject of crystallographic is
always challenging to explain how atoms or ions can form a unit cell that replicate it through a 3D space to form the macrostructure of a crystalline material.
That’s why is always necessary to use teaching aids. My project is designed to be a didactic help the teaching of this topic.
The idea of the model is a RGB LED cube of 5 x 5 x 5, the operation will be through an android app which will be used to select the crystal structure needed and the cube
will respond turning on the LEDs that correspond to the coordinates of the crystal structures.
There are many LED cubes done, but all of them are used for decoration or entertainment purpose, none of them have been programmed to be use as a teaching aid. Also, there are many crystallographic models but all of them only show one structure, or is made of pieces that need assembly and disassembly to show another 3D structure.
Next table shows the bill of materials and their cost.
| Material or component | Cost | Supplier | |
|---|---|---|---|
| Mexican Pesos | US Dollar (1USD ≈ 20 MXN ) | ||
| Acrylic sheet 3 mm (1.2 x 0.6 m) | $ 360 | USD 18 | Acrylplast Querétaro |
| Acrylic rod 6mm diam. (1.80 m) | $26.5 | USD 1.32 | Acrylplast Querétaro |
| RGB LED with chipset inside 200 pieces | $956 | USD 47.76 | Amazon USA (link) |
| Electrical wire Caliber wire (10 m) | $ 25 | USD 1.25 | Electrónica AMMA Querétaro |
| Solder (100 gr) | $130 | USD 6.50 | Steren |
| Total | $ 1497.50 | USD 74.83 | |
For the test of programming an Arduino uno is going to be use, however for the control of the LEDs (125 x 3) is necessary to build a multiplexing circuit with two LED driver (MAX7219) and ten transistors (PN2222A). This circuit is going to be designed and made in through-hole for testing and optimization. After that a PCB with SMT components will be made.
CAD, Laser cut, 3D print, electronics design, embedded programming, interface programming and networking and communication.
Assembly of the LED cube and programming.
The idea is to have a full-working prototype by the final presentation sessions, after that think in improvements and PCB productions for a final product. In the next table there´s a plan schedule for the development of the final project.
| ID | Activity | Progess | Comments |
|---|---|---|---|
| 1. | Design the LED cube (Solidworks) | 60 % | -- |
| 2. | Test and Learn the programming of LEDS | 80 % | -- |
| 3. | Find alternatives to the soldering between the LED’s | 30 % | Wildcard Week |
| 4. | Laser Cut the and construction of the cube | 0 % | -- |
| 5. | Connect the LED’s inside the cube | 0 % | -- |
| 6. | Perform test with Arduino | 0 % | -- |
| 7. | Design an interface to control the Cube | 0 % | -- |
| 8. | Design a PCB to control the LED’s cube | 0 % | -- |
| 9. | Integrate the PCB with the cube | 0% | -- |
| 10. | Final test with students and teachers | -- | After Academy |
| 11. | Create the git repository and instructables page | -- | After Academy |
| 12. | Improvements in design, programming and interface | -- | After Academy |
Must work and look attractive and the design intention must be visible and easy to understand.