Applications and implications --- Կիրառություններ և հետևություններ

Introduction --- Ներածություն

For this week we had to:
Propose a final project masterpiece that integrates the range of units covered, answering:
What will it do?
Who's done what beforehand?
What will you design?
What materials and components will be used?
Where will come from?
How much will they cost?
What parts and systems will be made?
What processes will be used?
What questions need to be answered?
How will it be evaluated? Your project should incorporate 2D and 3D design, additive and subtractive fabrication processes, electronics design and production, embedded microcontroller interfacing and programming, system integration and packaging Where possible, you should make rather than buy the parts of your project Projects can be separate or joint, but need to show individual mastery of the skills, and be independently operable (individual assignment)

What will it do?

My final project will be a 2 axis solar tracking device. It will track the movement of the sun with two axis. This kind of systems are used to increase solar energy harvesting. It is estimated that solar tracking can increase power output up to 30%.

Who's done what beforehand?

There are many types of solar trackers out there. And there are several successful projects by FabAcademy students.
FabAcademy 2013:
FabLab Barcelona Mathew Owen low cost solar tracker
FabAcademy 2016:
GreenFabLab machine building week Dual Axis Solar Tracker.
FabAcademy 2017:
FabLab Barcelona machine building week solar tracker.
FabLab Israel Ilia Feldshtein solar tracking cooker

What will you design?

My design will have worm gear transmissions for both axis in order to lock the system during winds and while motors are idle also to maximise the load it can handle. I will also put two pairs of thrust bearings one pair on each axle to minimise the wear and enable smooth movement.

What materials and components will be used?

I will use:
Plywood to make the frame and gears
PLA to 3D print the worms
2 DC (Jameco 253471) geared motors to move the system
Fr1 to mill the PCB.

Where will come from?

Plywood will be bought from a hardware store called "Russki Les"
PLA, FR1, DC motors are standard materials of fablab and will be provided by Dilijan fablab.

How much will they cost?

Total 38431 AMD 80.3$ (rate 1$=478AMD 30/06/2019)
2 DC Motor Jameco 253471 15296AMD (32$)
1 sheet of 150x150x10mm polished plywood 5800AMD (12.1$)
2 M6x90mm bolts(400AMD)+ 10 M6x35mm bolts(1000AMD) + 13 M6 nuts(500AMD) + 23 M5x20mm bolts(2300AMD) + 31 M5 nuts(465AMD)=4665AMD (9.7$)
5 female 2x2 2.54mm (320AMD)+ 5 male 2x2 2.54mm (250AMD)+ 2 female 2x3 2.54mm (320AMD)+ 3 male 2x3 2.54mm (250AMD)=4240AMD (8.87$) ?
4 thrust ball bearings 51105 3000AMD (6.2$)
2 ATtiny44 microcontrollers 1400AMD (2.9$)
2 LM3480IM3-5.0v regulator 800AMD (1.7$)
2 A4953 full bridge 760AMD (1.6$)
2m copper cable 500amd (1.1$)
9 smd resistors(45AMD) + 6 smd capacitors(30AMD) + 4 LDR 5528 Q5(400AMD)=475AMD (1$)
1m ribbon cable 478AMD (1$)
2 696ZZ ball bearings 300AMD (0.6$)
1 FR1 PCB board 717AMD 1.5$

What parts and systems will be made? What processes will be used?

The frame will be machined with shopbot (Substractive).
worm gear 3D printed Makerbot (Additive).
PCB design KiCad (electronics design and production).
PCBs will be milled SRM20 (Substractive).
ATtiny44 will be programmed using c code avrdude and gcc (embedded microcontroller interfacing and programming).

What questions need to be answered?

How to measure resistance.
How to calculate average values of 4 realtime measurments.
How to perform this project in one week.

How will it be evaluated?

According to FabAcademy Assessment document Our final project needs to demonstrate the skills we obtained during our study and prove our mastery.
It will be evaluated how affordable it is to repeat the project (less than 100$ ideally ~ 10$).
What percent of the parts is fabricated and what is bought.
How well is documented the process.