Newbie looking for clarification.

Using Arduino Project Guidance
#1

Hi all,

First post, and complete newbie, so I apologise if it's the same stuff you get asked all day long.

I'm after a little advice / clarification if possible.
The project I have in mind is a 4 motor watch winder.

The idea came after seeing a couple of smart looking home brew builds, and refusing to spend £120 on a cheap eBay one that is guaranteed to fail after a month.

I'm a complete Arduino novice, but not new to circuit building or the technical side of it.

I'm trying not to run before I can walk, but I've got an idea of what I want for my end goal and after research and seeing other builds I settled on Arduino as the solution.

The idea is as follows.

4 Stepper motors, each programmed to run a slightly different cycle.
Either activated by a button per motor (or a selector dial and a single button would be great)
a GPS receiver, to pick up a time/date feed and display via a 2 line display.
(The display may also be used to show watch data such as rotation speed, time of cycle remaining but that's not as important)

So before I actually open my wallet, am I best off going straight for a Mega for the extra connections, or will the Uno with a motor shield run everything I'm looking to use?

I've tried looking into it, but nobody seems to have a straight yes/no answer.
Several similar projects have either used 2 boards together I2C (seen with both 2x Uno and 1x Uno and 1x Mega) but with lots more features that I don't need, or they use 1 Uno and only run 1 motor.

Any advice / clarification is greatly appreciated.

#2

I don't see how you would need more than 1 Uno to do the job. 4 stepper motors with step/direction type drivers (like A4988 or DRV8825), 8 pins (+1 for optional motor enable). An I2C 16x2 or 20 x 4 LCD, 2 pins. A rotary encoder with push switch, 3 pins. GPS module to RX of a software serial port, 1 pin (+1 optional TX from software serial). A total of 14 (16 with options) pins of the 18 available on the Uno (leaving hardware serial for debug/upload). If you want 4 push buttons instead of an encoder, that could use only one pin using a resistor chain and 1 analog input pin.

#3

Why do you need 4 motors? Are you planning to wind 4 watches at the same time?

What sort of watches are you winding? Self-winding watches?

These links may be of interest
Stepper Motor Basics
Simple Stepper Code

also look up the AccelStepper library

...R

#4

Thanks Fungus,

That is exactly the sort of clarification I was after!

I'll get an Uno ordered up.

#5

@Levaz, my Reply #2 overlapped with your Reply #3

...R

#6

I got caught in the 'maximum posts in 5 mins trap' lol

I also currently own 3 self winders / automatics (as opposed to a mechanical hand wind), and am looking at a 4th, so it's a little bit of future proofing, and as the whole build is going into a display cabinet, 3 looks asthetically off balance in my opinion.

I'll take a proper look over the links you posted on my lunch break

#7