02. Some directions: Arduino + precision mechanical parts

There are many solutions for small size electronics and prototyping:

• Arduino: http://www.arduino.cc/
• BeagleBone: http://beagleboard.org/
• Raberry Pi: https://www.raspberrypi.org/
• HummingBoard... and more alternatives to Rasberry Pi

I had gotten started with Arduino as it is more of a micro-controller than a little computer (as Rasberry Pi) and I believe it is appropriate for real-time processing. Last summer, I got started with a starter kit which is a good solution to get introduction to basic projects, components, coding and learning, even for parents and kids: http://www.gotronic.fr/art-starter-kit-arduino-k000007-18743.htm

As far as the mechanics is concerned, I need some precision, specifically for linear guiding and I came across these websites from which I expect to get my most precise parts:

• http://www.igus.fr/
• http://www.norelem.fr/
• http://www.123roulement.com/ (bearings)
• http://www.a4.fr/ (shaft couplers, bearings)

A friend of mine reviewed my initial cinematic and also gave me the following advice:

"Precision is a matter of budget.

Now, a pair of copper plumbing tubes (which are, by construction, precise diameter and straight, when not welded), a plastic block in which you drill the diameter of your pipes and voila at lower cost (but you'll have to be lucky for forest of diameter to make it a tad more in diameter than the tube, but not too much, and accuracy will be won on the length of the plastic block).

There is a problem on your installation: it lacks a tension wire kit at the pulleys and you better make several turns over the "motor" pulleys. Balancing the strand lengths of 2 sides of the machine will be a crucial operation for its proper functioning => the connecting tube between the stepper motor and the bottom pulley (in the diagram) will be very steep for not having torsion."