how to make (almost) anything
final project

Please find below the development of this project. The concept was first thought of in 2017, and was developed over the two final weeks of the Fab Academy. This development is presented in chronological order, starting in January 2018.

20.01.18 / I drafted my final project before heading to Barcelona. Find below a comprehensive description of it:

15.05.18 / We are one month away from the end of the Fab Academy. Below is an update of my final project.

My final project can be divided in several parts:

Some of these parts could by themselves be a Fab Academy Final Project. The whole project is too big for a single student. therefore I went to Milan where two Fab Academy students are developing on a similar educational project called Fab Kit. We discussed about a potential collaboration.

Fabkit will be deployed in refugee camps, therefore, due to the inponderable of such situation, they wish to rely on paper or written tutorial rather than videos. There is no digital interface planned. Only one person - the instructor - has access to the tools, machines and materials, and give access to learners. These contraints limit our opportunity to immediately collaborate, excepted to produce and curate the content of tutorials.

To develop the prototype in the next 30 days, I will stick to the minimun required and make use of what I have already developed in the last 5 months. I will make:

01.06.18 /I have until the 11th of June to fabricate my final project - roughly 10 days. Below is my schedule :

01/06 : prototyping electronics

02/06 : design PCB

03/06 : design structure and kit

04/06 : milling, stuffing and programing PCB

05/06 : fabrication structure and kit

06/06 : production video and slide

07/06 : documentation

The last four days are safety buffer to finish what has not been finished.

I prototype the electronics :

Overall view :

Summary of the design :

Behavior :

The WIP code for all microcontrollers can be found here. I will update the wiring in the final documentation.

Useful links :

- RFID library ;

- Tiny Wire Library;

- Simple I2C between arduino with the Wire Library";

- Software Servo Library ;

- using UID's tag to trigger a function.

02.06.18 /I designed the PCBs, master and slave :

The designs can be found here.

Useful links :

- bootloading an ATMEGA328P-AU .

03.06.18 /I designed a test for the outer structure of the learning kit:

Using designs from the two websites below is troublesome - format issue : scale and geometry is incorrect or too complex.

Useful links :

- Nintendo Labo for inspiration and locking system;

- Gear generator;

- Iris calculator.

04.06.18 /I mill, stuff, bootload and program the PCBs :

Note for next version :

• - Double sided milling or extra perforation for the wire to be added ;
• - Add the pull-up resistors for the SDA and SCL line to the master board;
• - Merge the two ISP 2x3 male headers into one;
• - Use more solid connectors to connect various components to boards.

Bootoading requires a consistent electricity flow. Below extra source is provided to make it work.

cardboard design from yesterday.

Useful links :

- soldering with flux.

05.06.18 /I design the casing. I focus on the iris mechanism :

After a first approach (above) I do a clean design of the iris :

The design can be found here.

Useful links :

- putting together cardboard piano from Nintendo Labo ;

- making gears in Fusion360.

06.06.18 /I carry on with the design of the iris. I fabricate the mechanical design and actuate it :

Testing code, thanks to BARRAGAN and Scott Fitzgerald :

/* Sweep*/

#include

Servo myservo; // create servo object to control a servo
// twelve servo objects can be created on most boards

int pos; // variable to store the servo position

void setup() {
myservo.attach(9); // attaches the servo on pin 9 to the servo object
}

void loop() {
for (pos = 70; pos <= 180; pos += 1) { // goes from 70 degrees to 180 degrees - smaller range than expected
// in steps of 1 degree
myservo.write(pos); // tell servo to go to position in variable 'pos'
delay(15); // waits 15ms for the servo to reach the position
}
for (pos = 180; pos >= 70; pos -= 1) { // goes from 180 degrees to 0 degrees
myservo.write(pos); // tell servo to go to position in variable 'pos'
delay(15); // waits 15ms for the servo to reach the position
}
}

I know know that I have until the 15th to finish my project. I also realise I can break down my final project into smaller chunks. The design consist in several steps : - 1/iris, 2/connectivity, 3/ packaging of the base and 4/packaging of the learning kits. I re-plan my next week :

01/06 : prototyping electronics

02/06 : design PCB

03/06 : design structure and kit

04/06 : milling, stuffing and programing PCB

05/06 : design of Iris

06/06 : fabrication of Iris / design of connectivity

07/06 : fabrication of connectivity

08/06 : design of the base and kits, day 01

09/06 : design of the base and kits, day 02

10/06 :

11/06 :

12/06 :

13/06 : production video and slide

14/06 : documentation

08.06.18 /I designed the USB connections between kits and designed the casing for the kit. I also designed a drawer and the structure it will rest on :

After a couple of iterations, I get to this :

All design files can be found here.

Useful links :

- code o pillar : fisher price - sweet clipping system ;

10.06.18 /I design the base and adjust details of the design:

The base.You can find the design here.

top and bottom connectors are now doubled to ensure extra modules added on top of each other are aligned and stable. They are sitting on the transversal structures to leave space for the drawer.

Addition of an extra bearing to keep the actuator in position.

Re-design of the pins holding the bearings for a tighter fit.

New cut for tomorrow.

12.06.18 /Over the last couple of days I finished the cardboard design and the electronnics (setup and production of final items).

I corrected the support for the USB plug so they are more study and easier to assemble

correction of the first kit and fabrication of the second kit

wiring and producation of an extra PCB for powering and adding pull-up resistor for the I2C network.

The designs files (rhino + eagle) can be found here .

13.06.18 /I put together my final project today.

the whole setup, opened up...

...and put together.

I add a cardboard casing for all PCBs. Here for the back of each casing.

The ISP male headers are easily accessible (on the back of each casing) for reprogramming and the I2C connection can be unplugged when doing so :

In the base, the master PCB and the power/pull-up resistor for the I2C network:

A final look at the setup before testing :

I make the explanatory video (with Open shot Video Editor) and two slides (with Krita) which are at the top of this page.

14.06.18 / I populate the summary (above) with new content and attempt to write a comprehensive tutorial to replicate this design from scratch which can be found here .

15.06.18 /Now the presentation is over I take a second to reflect on what aspect of this design could be improved :

Casing

• - The thickness of the casing can be diminished. To do so the the servo can be relocated in an angle of the casing. Also, the slots into which the the driving gear pushes can be cut in the middle of the actuator ring rather than the bottom :

• - Following the same thinking, the PCBs could be located in a corner on the back of the casing, thus the casing length being shortened.

• - Each PCB could have a shape that allows it to fit and be held into place within the inner structure of the casing .


• - the driving gear can be redesigned so the servo fits in, making the whole system more sturdy :

• - is there servo of that size able to turn further than 180 degrees? my guess is that there is. To be looked into.

Capsule (drawer)

• - re-design so that it looks more like a classic time-capsule AND shows rounded tips on each sides with a sample of what the capsule offers. This sample can be seen when the capsule are locked in their casing.

Other elements and consideration

• - the RFID tages can be re-designed as printed or molded shapes which can be mounted on bracelets or necklaces, and flat enough to fit in a wallet wihout making too much of a bump :

• - the inner cut of the front layer which circles the actuator ring should be larger by a few millimeters, ensuring that the actuator ring will spin easily, being in contact with the bearings and the bearings only;


• - All parts playing a part in the motion of the Iris ( the four structural components directly in contact with the servo, the two bottom beams and the actuator ring) could be re-cut in 4mm plywood, to ensure sturdiness over time.

This concludes my comments about my final project and its developpment during the Fab Academy.