CocoMake7

Prototype using Arduino, QTouch and Coconuts

A jugaad ultra low-cost clone to the Makey Makey, but based on QTouchADC sensing, local manufacturing and coconuts

http://hackteria.org/wiki/QTouchADC_Library_for_Arduino

Board Design

On GitHub

https://github.com/CocoMake7/ not working at the moment...

Comparison to Makey Makey

Resistive sensing vs. capacitive sensing

NO NEED FOR SECOND ALLIGATOR-CABLE!

By using the QTouch ADC method, the analog pins of the microcontroller can be turned into capacitive sensor, without the need of any external circuitry.

Low-Cost

the official kit from Makey Makey

The Makey Makey kit incldudes, the board, some alligator clips, USB cable and a booklet, cost 49$, or 3'500 IDR. Far too much for many schools in india or worldwide.

We are aiming at Bill of Materials prize of approx 3$ for small scale production (5-25pieces). can be reduced to 1.6 - 2$ for large production series (1000 pieces).

Just a general thought about different interpretations of "low-cost" in the West... in China... and in India?

Let's see what we can make/produce in India...

Jugaad

We make it as cheap as possible, including capability for local manufacturing. DIL-package, easy available parts, 1 sided PCB design and protoboard design, fancy PCB for collectors and geeks.

Which AVR microcontroller to use?

ATTINY 84

availability ok, prize starting around 150 IDR (2$), 1.50$ from Mouser, goes to 0.83$ if you buy 1000.
8 ADC channels

What's the difference beetween attiny84A and attiny84 or Attiny84V (Low Power and expensive?) or Attiny841 (new edition of attiny84 or attiny84A)?

ATTINY 25/45/85

availability ok, prize starting around 85 IDR (1.20$)
only 4 ADC channels

ATMEGA 328P

very widely available, prize starting around 220 - 250 IDR (3$), 3.48$ from Mouser goes to 1.82$ if you buy 1000.
The smd chip has 8 ADC channels, but the DIL seems to only have 6 ADC channel on Port C, ADC0 - ADC5
other extra pins for doing stuff

Download ATMEGA328 datasheet

ATMEGA 32u4, same as leonardo or the makey makye

only smd package
High prize, 6.32$ from Mouser
Hardware USB support!

Design Concept

Download pdf: File:CocoMake7_concept_Diagram.pdf

Related Projects

HID Keyboard emulation

V-USB virtual USB emulation on ATMEGA

http://www.obdev.at/products/vusb/hidkeys.html

Trinket Pro, ATMEGA 328 with bootloader and HID key libary:

https://learn.adafruit.com/pro-trinket-keyboard/library

Turn your Arduino UNO into a HID keyboard

http://wiki.sgmk-ssam.ch/index.php?title=Arduino_Uno_R3_as_HID

Makey Makey - 49.95$

Makey Makey on Sparkfun - $49.95

https://www.sparkfun.com/products/11511
Datasheet, Schematics: Makey Makey Schematics

Make something like the Makey Makey with Arduino Leonardo

http://blog.arduino.cc/2013/03/23/how-to-make-makey-makey/

Make your own Makey Makey, based on Shrimp (Bareduino)

http://fromscratched.nl/index.php/shrimpkey-maak-je-eigen-makeymakey-deel-3/?lang=en

Scratch - free

Create stories, games, and animations Share with others around the world. A creative learning community with 8,808,476 projects shared. With Scratch, you can program your own interactive stories, games, and animations — and share your creations with others in the online community. Scratch helps young people learn to think creatively, reason systematically, and work collaboratively — essential skills for life in the 21st century. Scratch is a project of the Lifelong Kindergarten Group at the MIT Media Lab. It is provided free of charge.