Week 3 Day2
Many of the fabacademy cad items are design that have .cad extension. These were designed in kokopelli. .cad file is basically a python script. Today we try to edit and understand how the script ad kokopelli.

Assignment
We add components to a hello.ftdi.44.cad and wires on a board and fabricate it.

Process
The following were attempted in kokopelli on hellofdti cad file downloaded
Adding components
Position components
Add traces
Increase board length
Reposition elements
Rewire
I downloaded the hello ftdi files from fabarchieve from the links.
 http://academy.cba.mit.edu/classes/embedded_programming/hello.ftdi.44.cad
 http://academy.cba.mit.edu/classes/embedded_programming/hello.ftdi.44.png
Experimenting Commenting and uncommenting the lines from line number 20 onwards allow us to get desired out put.


From line 5593 onwards where "#define board " starts we can change the parameters like width of line, board width and length etc.
The code goes like 
#
# define board
#

w = .016
width = 1
height = .93
mask = .004
x = 1
y = 1
z = -.005
d = .06

 It is not recommend below for trace width(w) to be lesser than 0.012. Assign intelligent values for these parameter and let it remain default unless theres a problem. 

Design
The following editions were committed in the file. this code is added under #define board and before #select ouput. The PCB had trouble with placingthe 6mm push button, hence we had to resize the board make it wide and reposition IC. Code:

# define board
#

w = .016
width = 1.2
height = .93
mask = .004
x = 1
y = 1
z = -.005
d = .06


....Uneditted code
.
.
 # repositioned the IC. Every other element seems to                                                  #positioned relative to the ic.

pcb = wire(pcb,w,    IC1.pad[13],
   point(IC1.pad[13].x+.105,J2.pad[4].y,z),
   J2.pad[4])
.
.
.

 #adding led
LED1=LED_1206('Led')    #usually the format is like component_size('name')
pcb= LED1.add(pcb,XTAL1.x,IC1.pad[5].y,z,180) #showing the led
 
R2=R_1206('R2\n1k')    #adding resistor and naming it "R2 1k"
pcb= R2.add(pcb,LED1.pad[2].x,LED1.y-0.15,z,-90)

B1=button_6mm('B1')   #adding push button
pcb=B1.add(pcb,LED1.x+0.2,J1.y+0.05,z)

pcb = wire(pcb,w,         #adding traces
   IC1.pad[5],
   LED1.pad[1])

pcb = wire(pcb,w,
   LED1.pad[2],
   R2.pad[1])

pcb = wire(pcb,w,
   J1.pad[6],
   R2.pad[2]
   )
pcb = wire(pcb,w,
   IC1.pad[6],
   B1.pad[4]
   )
pcb = wire(pcb,w,
   J1.pad[6],
   B1.pad[3]  
   )

Exporting as .png
(make sure you name the file with the extension or else the export wont work and throw an exception)

Machining 

Machining parameter
Milling output
 
Final Output after stuffing with components.
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Preparing Laptops and Lab Computers

Since fabacademy philosophy roots in opensourcing it only makes sense that Ubuntu and the free softwares are used. This allows free and ope access to anything and everything that is done in fablab. It allows repetability and a common framework that anyone can work with. One of most important of them is the OS itself which is the linux based UBUNTU system. The next most inportant software is  the fab modules which can control alomst any CNC machine that is present in fablab.

The pain of Ubuntu 

Ubuntu means 

"A quality that included the essential human virtue; compassion and humanity. there is a need for understanding not vengance, ubuntu is not victimization"

Indeed you need to have a all these to go through Ubuntu install and setup.

Creating digital accounts

During fabcademy you will be evaluated through your documentation which explains the world and the remote mentor or Neil what you have done. There will be times when your projects will be recommended by your remote mentor to higher faculty or Neil. They will see your website or the files you created. For these reason you need to learn to effectively express your work in a document. They should be online and freely available to anyone, they are opensource.

Day 4 week 1

Lab maintenance and Material handling

I took charge of Vinyl cutter and Roland Modela

I learned how to better handle the vinyl rolls. The vinyl rolls when kept vertically deform and get damaged at the edge which happens due to it not being able to support its own load properly. The correct way to keep a vinyl material is horizontal and the rolls to be taped at the open edge after use so that they don’t become loose.

The vinyl rolls were kept on the ground earlier.

Vinyl cutting

Used to make sticker and best use is to make PCB that are flexible. Can cut copper, epoxy and vinyl sheets.

Loading the material 

Use this lever to release or secure the vinyl.

Materials should be between the two translucent patches as shown in the picture. These have rough surface in order to grip the papaer better. The wheels should secure the paper when the lever is engaged.

Day 2 w2

Laser in our fablab is a trotec speedy 100 with that we have an atmos exhaust filter from trotec. Here's the laser machine and our super cool prefab guide and fabguru Francisco explaining about the filter system.

Polycarbonate lid and Atmos Exhaust Filter system

Filter parameters

Things to watch out for

Exhaust filter should be on.

Molding Casting and Roland Modela

The basic idea for this session is to create an 3D object through computer and try to make it in machinable wax in such a way that a molding pattern is created directly from it. Roland modela will machine the wax. We will try to replicate this object by creating a silicone mold and later use the silicone mold to cast hard plastic into it.

Day 5

Shopbot

Notes:

Designing for milling

Due to tool radius inner corner of a hole or a pocket cant be sharp. Overmilling is advised in such cases.

Good design guidelines for milling.

http://blog.inventables.com/2014/06/learn-about-milling-inside-corner.html

http://www.efunda.com/processes/machining/mill_design.cfm

Better to use antimony to design material to be milled.

Dia max to be used for milling in shopbot- 6mm

Dia max to be used for milling in roland -3mm.

Week 3 Day 1

This week we move to electronics design and fabrication.

Today we started with electronics production. The goal was to fabricate a pcb from an already existing design. We use roland modela to fabricate the PCB.

Assignment: to fabricate a version of fabISP using Roland modela and fab modules.

Process

We downloaded the the following designs.

Week 3 Day2

Many of the fabacademy cad items are design that have .cad extension. These were designed in kokopelli. .cad file is basically a python script. Today we try to edit and understand how the script ad kokopelli.

Assignment

We add components to a hello.ftdi.44.cad and wires on a board and fabricate it.

Consider the following methods of programing a microcontroller

Arduino ide- most user-friendly, many tools, quick,  easy

C  - intermediate difficult, need to have more hardware knowledge, more efficient in code handling and storing, more freedom to program.

Assembly lowest level of programing, need to have through understanding of the hardware also, more difficult, highly efficient in code handling and occupies least storage, and allows most freedom to program.
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