Project:TRTL
Turtle Robot T Logo
Don't ask me what the T stands for. I've forgoten.
Project Aim
To produce a low cost kit robot that is simple to build, and easy to use/program via software with the aim of introducing and kids and adults alike to building, making, electronics and software. For certain values of building, making, electronics and software.
Project Participants
Amran
Jonty
Chris (hipster)
Concept and ideas dump
TRTL is intended as an educational/learning device. It is not a toy to keep. it is only just for christmas.
TRTL should be built upon existing open hardawre/software stacks. ones with active/lrage communities attached to them. This will make the tranisition from TRTL to general hacking a simple process. It also adds value to the kit - the purchaser not only gets a TRTL bot and its inherant educational process, but also an 'AVR clone' - the entry point into the land of arduino.
Hardware: Nanode Sofware: Wrapper over bitlash/arduino processing environment (with possibly a cutdown LOGO language intbetween? implemented as custom bitlash functions)
Why Nanode?
We know the designer. We know the hardware. We can customise it and build just the 'AVR' part (ie the arduino compatible bit) for much less than a nanode would cost. Once the TRTL is built, if the owner wants to progress further into the hacking arena, he/she are presented with two paths. stick with the arduino clone, or build up the remaining nanode components to get a full blown nanode.
Ken Boak has supplied the following as an outline costing:
"The bottom line is £10.20...but there are several things you can then remove.. This brings you down to £8.07"
we will take the higher costing of 10.20GBP as a conservative estimate of cost.
As production of the nanode becomes more efficient the cost is further expected to drop. A figure as low as 7 GBP has been estimated. However until a nanode has been delivered at this cost level, it would be foolish to assume that it will.
Why Arduino/Bitlash
Arduino is an easy to use protyping language developed for ATMega32 based microcontrollers. There is massive community support for all things arduino. This choice is in line with the project aims to build on existing community supported platforms.
The use of bitlash is up for debate since i cant think of one good reason it should be used over an arduino sketch, but i like the idea of creating custom functions and executing them for movement et al.
Detailed milestones
Cost effective prototype Working electronics Finaliased physical design
UI design Functional software for comms to nanode via bluetooth
Making it go back back, forth and forth.
How much should it cost
15-20 GBP
Prototypes
There will be numerous prototype. Initial outline is five.
Protoype 1
Aim - to build a TRTL bot and get a rough cost estimate for this prototype Only buy items that can also be bought in bulk. Do not include postage costs fo rmaterials.
Generate interest for the project.
Materials Required
1/6 x 600x300mm MDF sheet
2 x wooden wheel
2 x cheap chinese motor
1 x nanode AVR spec
1 x bluetooth module for serial communication to AVR via SPI
2 x 3D printed castor
2 x marbles (if using on non hard/laminated surface?)
1 x H bridge
Material Cost (per unit)
1.05 GBP - MDF sheet 600mmx300mm http://www.hobartlaserables.com/wood/mdf/4mm-laser-grade-mdf-600x300mm
0.70 GBP - wooden wheel 60mm (http://www.alwayshobbies.com/Models/Wheeled-Toys/Wooden-Wheels/Wood-Turned-Wheels-60mm.ice)
0.50 GBP - cheap chinese motor
10.20 GBP - nanode AVR spec (via Ken Boak)
4.69 GBP - bluetooth module for serial communication to AVR via SPI (eBay special!)
0.20 GBP - 3D printed castor (via London Hackspace - approx cost)
marbles (if using on non hard/laminated surface?)
H bridge
Cost for prototype
All costs in GBP
0.175 - 1/6 x 600x300mm MDF sheet
1.40 - 2 x wooden wheel
1.00 - 2 x cheap chinese motor
10.20 - 1 x nanode AVR spec
4.69 - 1 x bluetooth module for serial communication to AVR via SPI
0.40 - 2 x 3D printed castor
2 x marbles (if using on non hard/laminated surface?)
H bridge
Total: 17.865
Prototype 2
review materials used and initial design. refine prototype to 'RC' state.
Prototype 3
supply kit to intended user. ask them to build it. debrief/review, modify accordingly
Prototype 4
????
Prototype 5
Profit
Source of materials
a general source/reference for where i bought materials
http://www.alwayshobbies.com/Models/Wheeled-Toys/Wooden-Wheels/Wood-Turned-Wheels-60mm.ice
http://www.alwayshobbies.com/Models/Wheeled-Toys/Moulded-Wheels/105mm-Moulded-Spoke-Wheel.ice
Misc/Scratch/TODO
possible use of http://arduino.cc/blog/2009/03/09/snap-on-panel-for-arduino-based-instruments/
add interface design pics and rational for 'page flow' in the app
