On the first plan i want to make a special board with a MCU for the room temperature & humidity sensor, but for a easy work i plan to do it directly connected to the Motherboard, for this i juste make a simple board that handle the Si7020-A20 I2C humidity & temperature Sensor. this sensor was quite triky to solder to the board, is a 3mm by 3mm square with 7 pin under it....

On the prototype i made of it i forgot to rally a pin i just repair it by adding a small jumper on it.

The files for this board is Here

I have probleme with the result it gave to me ( about 3k°C and 800% humidity on a normal room... ), for the moment i put it on the side to be able to finish my project on times and come back on futur to fix it.

♦3D printed Parts:

On my final project i include some piece on 3D print. All of this parts is made with the same filament and the same settings, on a Alfawise U20 printer

Setting:

• layer height: 0.1mm
• Wall width: 1mm
• Top & Bottom thickness: 0.8 mm
• Infill: 20% with a Gyroid pattern
• Nozzle temperature: 220°C
• Bed temperature: 60°C
• Print speed: 60mm/s
• Build adhesion: None
• Support: None

The filamant i use is the Volcano PLA by Formfutura, i love this material giving a really nice mat black result & a nice finish surface.

= Axis support =

I try to make this part by molding & casting & it gave me a nice result but infortunatly i don't have a perfect flat surface and when i do my hole on it is not perfectly perpendiculare. So for gain some times on work i decide to remake it by 3D print

Files here

= Stepper support =

This parts is design for place the 3 Stepper in place to faces the gears

Files here

= Sensor Holder =

This one is here to align the homming sensor with each of the 3 gears of the project.

Files here

= Temperature & humidity sensor window =

I design this piece to have a good measure for external temperature & humidity with the SI7020 Sensor.

Files here

= Project enclosure =

The last printed part is made to handle the wooden face and the PMMA back piece and assure the full enclosure of the project. It also assure the good placement for the LED arrays i made.

Files here

♦Laser Cutted Parts:

Some of the most important parts of this project is made by laser cutting let's take a look at this:

= Back panel =

this piece is one of the most important, it's the base for screw every thing on place. It's cut on a black PMMA

Files here

= Gears =

For my mechanical display i cut on a transparent PMMA 2 kind of gears:

- The first kind of gears is the one use for the Lixies effect for this i design large gears where i engrave all the differents weather symbol.

- The second kind is to drive the dispaly gears with the stepper motors.

Files here

= Screen =

On a clear 3mm thick PMMA i also cut two piece to make a protective screen on the face

Files here

= little pieces =

The last pieces i cut on laser for my project is some interlayer for space a litle the display gears and for keep the LED light on each disk.

This bundle of parts is made on a 0.5mm PETG sheet.

Files here

♦CNC machined Parts:

The last part of my project i have to make is the front panel

= Front panel =

This panel is made on teak wood and machined on the shopbot ( you could see more about workflow on the shopbot on Week 7 )

I do some post processing on the faces by ronding all the angles & engraved it. ( for have the good placing on the lasercutter for engrave my wood i start by cut the outline of my woodparts on a fixed cardboard. )

Finish by passing some linen oils on the wood for a better result

Files here

♦Development, Prototyping, Test & Debuging

When the first batch of piece is finish i start by making some test for controll my code and see if everything is right or not. to this i use some breadboard and a lot of jumper.

Durring this debugging moments i start to have some headhaches with the communication between the ESP board & the ATTiny one, testing each one separatly show no problem on the serial communication, but if i try to make it communicate together i cant have a good result. Finaly i find the problem:
The adafruit neopixel libraries is not compatible with the 20MHz clock of the ATTiny1614. I change for the tinyNeoPixel libraries include on the Spence & konde Megat=Tiny cOre

On side of this test and debigging phase i finish to produce all my parts and start the final assembly.

♦Assembly & Integration:

On the following photo you could see all the process of assembly step by step:

During the assembly & final programming process some issue occure, due to a number of connect & disconect for test and programming some pinheader start to be snatched off my boards

But i'm not anymore on the lab so for fix it i use some short jumper cable and a lot of hotglue to keep it in place

Not a pretty style but it's functional.....

♦Final result:

On the next photos you could see the result of the supperposition of the 3 gears for a Sunny-cloudy-rainy days: