13 - Applications and Implications¶

Realizing How Late You Are

Tools & Assignment

Updated for 2019 evaluation standards!

Task

Propose a final project that integrates the range of units covered.
See Final Project Requirements for a complete list of requirements you must fulfil.

* Your project should incorporate 2D and 3D design,
* Additive and subtractive fabrication processes,
* Electronics design and production,
* 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

Learning outcomes

Define the scope of a project
Develop a project plan

Have you?

The answers to the questions above will allow you to create your BOM, or Bill Of Materials.

FAQ

Q: Why do I have to answer these questions?
A: These are questions to help you plan your final project. Answer these and any other questions you think will help you do this.

(Copy of my 2016 website, with spelling corrections :)

Preamble¶

I didn’t change the scope of my final project. While it’s proving a serious challenge, I’m still hopeful in its success.

The Lecture¶

On our 7^th lecture Neil described the different types of project we could create and that previous students proposed. This followed a long list ranging from Robotics to Furniture.

Answering the questions¶

What Will It Do(?)¶

I want to create a robot with the capability to reconfigure autonomously into a variety of shapes which set by the user.

My output device / actuator is going to to be the EP magnet (or the connector / movement actuator) and all the correlated communication need.

While my necessary input device will most likely be a switch to turn on and off the entire system.

Who’s Done What Beforehand(?)¶

Reconfigurable robots / self-assembling robots (distinguished by self-assembling matter [eg. claytronics]) are widely researched in universities.

Various different approaches are used, using different types of forces including electromagnetic forces, electrostatic forces, etc.

Looking through the documentation from previous years I could not find anything I could use; however I did find very interesting research done by a student of Neil in 2010.

Robot Pebbles proposes small, 12mm cubes which use a type of magnetic connectors called Electropermanent magnets, this is what I was hoping to use for my project.

It has proven difficult to mimic robot materials used at the MIT, which has access to custom fit parts, such as very tiny magnets and low-carbon steel and & iron hyperrectangle (which I attempted to make myself using steel nails).

However this design has proven hazardous to follow, so the following page describes a process which may change for the final presentation. What materials and components will be required?

What Materials & Components Will Be Required(?)¶

-> Microcontroller

-> Electropermanent connectors

-> Capacitors

-> MOSFET

-> Copper PCB

Where will they come from(?)¶

-> PCB components [Microcontrollers & Capacitors] are available at the FabLab @DeWaag

Magnets¶

-> Neodymium [3mm diameter, 6mm length, rod shaped, tot. # 60 ]from Supermagnete

-> AlNiCo [3mm diameter, 12mm length, rod shaped, tot. # 30] from Conrad

How much will it cost(?)¶

While I do not know the cost of the components I am using from the FabLab [Need to check], the total cost of the magnets amounted to 40 Euro (including shipping).

What parts and systems will be made(?)¶

The supporting structure for the cubes will need to be fabricated, including the electropermanent connectors and PCB.

What processes will be used(?)¶

To create the electropermanent magnets I still need to perfect a method, the most difficult part is making the iron/steel cores, at the moment I made several by grinding away at a nail, this is not precise and I am looking it having custom made / changing design.

To make the structure of the cube, I will first cut it out of MDF with the laser cutter.
I later would like to change to a lighter substance, perhaps by moulding and casting (If I have time).

The PCB will be milled at first to test the components, however for it to fit in a cube it will, most likely, need to be printed using the Vinyl cutter and copper tape, to make it flexible.

What tasks need to be completed(?)¶

-> Design(to do) and create (to do) a PCB to control EP-magnets and cubes

-> Design(done and fabricate (to do) structure of cubes

-> Program (researched) and implement (to do) a mean of communication through the cubes via EMP.

What questions need to be answered(?)¶

1# Are EP magnets strong enough to move the cubes such that they will reconfigure? If not, how can I change the design.

2# Will I be able to transfer data and power over the cubes using the contact surfaces and EMP?

What is the schedule(?)¶

Finish everything before the 15^th of June.

How will it be evaluated(?)¶

Phase I Evaluation: I will no my project works when I will be able to control through the computer the activation, thus magnetization, of each surface on a single cube.

Phase II Evaluation: Through the computer I am able to control the magnetization of multiple cubes, through which I am to move them and (hopefully) create the desired shape.

2019 - Tasks¶

Propose a final project that integrates the range of units covered¶

Your Project Should Incorporate 2D & 3D Design:
- 2D design -> Circuits (KiCad) & pads(Inkscape)
- 3D design -> Box (Antimony) & Pawns (Antimony)
Additive & Subtractive Fabrication Processes:
- Subtractive: Circuits & sensor pads (3018 CNC) -Additive: Box & Pawns (Ender 5, 3D printer)
Electronics design and production,
- Custum CapSensing board
- Custum TFT LCD control board
Microcontroller interfacing and programming,
- i2c and serial communication between two boards
- CapSensing & TFT screen control using Arduino IDE
- Full GUI based game created in Adafruit GFX Library
System integration and packaging
- Fully enclosed system
Where possible, you should make rather than buy the parts of your project -> Made:
- Enclosure
- Circuits
-> Bought:
- 3D printing filament
- TFT screen
- Misc electronics components

Answering Questions¶

What will it do?¶

The aim of my final project is to recreate the original hexapawn game, which is a game designed to get better the more it is played.

This will be achieved a bit differently then normal hexapawn, because what would normally be within matchboxes in the original, will be contained in the AVR, but it won’t be fully software because the interface to the AVR will be through physical pawns that the player can move.

Who has done what beforehand?¶

Martin Gardner, the original creator of the game proposed to play it using match boxes.

As far as I know, a LOT of people have done physical implementations of this game (eg. using match boxes and paperclips), several have created a fully software version of this game, but none that I can find who have done a hybrid between the two, which is what I’m doing. Even less anyone who’s done so as part of the FabAcademy.

What materials and components will be used? & Where will they come from?¶

Amazon ¶

Copper clad board (set of 10 x 2)
0.1mm 20 degree mill bit (set of 5)
0.8mm end mill (set of 5)
USBtoUART cable (x1)
2.8 TFT LCD screen (x2)
LED power switch (set of 10)
Geetech wood PLA filament 1.75mm (1kg, 1 spool)
2.54mm pin headers (assortment)
THT capacitors (assortment)
0805 resistors (assortment)
0805 capacitors (assortment)
0805 led (assortment)

Farnell UK ¶

AtMega328p (x3
ATtiny44a (x5)
16 MHz Crystal (x8)
Tactile switch (x20)
(and more which I didn’t use)

3D Filaprint ¶

Protopasta Conductive PLA 1.75mm (500g, 1 spool ~ expensive stuff!)

How much will they cost?¶

Difficult to estimate since I had to buy all the components from scratch the cost was considerably higher. If the price would be on a per-item basis & on demand (for example for things like the protopasta PLA), like I broke down in my final project page, then I estimate the price to be around 25~30£, depending where you source your components.

The most expensive element, on it’s own, is the 2.8 TFT LCD at 13.5£, as a whole the most expensive by far is the protopasta PLA at 60£ for 500g (this doesn’t count the machines I had to get obviously). At roughly 0.12£ per g, the pawns which I printed at weight 39g, would cost 4.68£.

The reason the protopasta PLA is necessary is that capacitive sensors are triggered by differences in capacitance. There aren’t many materials that act as ground as well as the human body does, so the only real solution is to have some form of conductivity from the human body to the pawn itself. The only easy way to do this is with conductive filament.

That means the basic starting price is at least 18.18£, without taking in consideration the other components.

What parts and systems will be made? & What processes will be used? What will you design?¶

There are 6 major parts: 1. The touch pads: CNC milled from copper 2. 1 TFT control board: CNC milled 3. 1 capacitive sensor board: CNC milled 4. 6 Pawns: 3D printed from protopasta 5. The lid of the box: 3D printed from wood PLA (with black PLA as finishing touch if desired) 6. The body of the box: 3D printed from wood PLA

I’ve designed all of these components, sometimes with help from tutorials, credited in their respective weeks.

What questions need to be answered?¶

As I’ve said in week19, since I write this after the project is completed:

I’ve got no outstanding questions, maybe investigating the possibilities of:

Making the tft touch functions work
Integrating the capSense and LCD boards into one.
Adding a DMA for the LCD board
Adding a level shifter for 3V logic on the LCD
Using a 20MHz crystal rather then a 16Mhz, since the AtMega328p is rated for it.

How will it be evaluated?¶

Can it play the game?
Can it learn to play better?
Is it simple to use?

Header Image¶

If you are wondering what the header image is, it’s a reflection on the wall of the box of my project being printed.

It’s produced by my glass/mirror heating bed :)