Open sourcing electronics/microprocessor projects

GHA

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Over a few years I've gathered up a few bags of eBays finest electronics bargains and have spent many a happy hour tinkering with mostly arduino. With a few project ideas on the go, and being natural messy I thought I'd make a bit of an effort to have a more structured approach and log the design and software as it unfolds. So why not put the whole lot out as open source so anyone can join in, and maybe learn from others along the way.

But where to share? Fritzing seems an ideal starting point, circuit design and code can all go in one place. I haven't really dug deep into github - any comments? Not sure it's worth it in the early days.

What to make, initially a little box with 2 wires in, 2 wires out which could log voltage, current and temperature onto an Sd card could come in very useful on a boat now and again. And not that hard to make. I've a uno based fridge thermostat. A proper constant current battery capacity tester would be great.

Fledgling first steps on fritzing here...
http://fritzing.org/projects/vct/
The code is the *.ino file.



Interested, anyone?
 

pmagowan

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Im interested but can't be much help as I am just at the fiddling stage with arduino. I have loads of ideas but my coding is just at the level of getting LEDs to do what I want. I am also researching how to get lots of arduinos to talk to a raspberry pi and how to develop a gui. Once I get stuck in I might be able to add something.
 

laika

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I haven't really dug deep into github - any comments?

Yes :)

I'm scared of github. First you get convinced to put your (boat-related) code onto github. Seems like a good call: people can muck about with your code as you develop it so they can have fixes immediately (at their own risk) before you've tested enough to do a formal "release". They get early fixes, you get alpha testers. Ah but you're stepping out of your own private workflow based on How We Did Development Back In The Day. Once on github the young and the passionate expect you to know How Things Are Done There. And there's all this other stuff you didn't know about. People log "issues". Send you "pull requests". People point out that the tarball they downloaded doesn't compile. Ah! They're using that github feature you didn't know about which creates a download without doing all the stuff your carefully crafted workflow does which makes *your* "official" download compile.

There be dragons there. A lot to learn. Slowly getting the hang of it.
 

William_H

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A battery capacity discharge tester can be fairly simple but nt using Arduino. You use one of those cheap analogue battery powered crystal clocks. They run off 1.5 volts. For Nicad or NiMh batteries you run the clock off the battery and fit an appropriate sized ressitr in parallel. ie 1.2 ohms for a 1 amp rate. Set the clock to miday 12pM and it will stop when the battery is flat. With hours indicated on the clock.
Now if you want to discharge a lead acid battery you don't want to flatten it so you make up a comparator voltage monitor which feeds the clock via a dropping divider resistor so clock will run off the 12v but will stop when the desired low discharge voltage is reached. For better accuracy you make up a constant current discharge circuit. olewill
 

GHA

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For probably not much more money and maybe a just little more time you can automate the process and log the voltage & current with an arduino...

Discharge%203-4-14_zpsjnnp5mdk.jpg~320x480


A few more pennies would add a relay to cut off the load at a set voltage, these batteries are getting ditched so it didn't matter.

Next step in this project is to add some FET's so the load can be kept constant and log the battery temperature as well. What isn't immediately obvious is what to use as a power drain though, cheap and easy to get. Car headlight bulbs aren't that cheap and are a bit fragile, and old bar heater or something?

Has anyone actually tested their boat batteries on an accurate C/20 constant current device?
 

GHA

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Yes :)

I'm scared of github. First you get convinced to put your (boat-related) code onto github. Seems like a good call: people can muck about with your code as you develop it so they can have fixes immediately (at their own risk) before you've tested enough to do a formal "release". They get early fixes, you get alpha testers. Ah but you're stepping out of your own private workflow based on How We Did Development Back In The Day. Once on github the young and the passionate expect you to know How Things Are Done There. And there's all this other stuff you didn't know about. People log "issues". Send you "pull requests". People point out that the tarball they downloaded doesn't compile. Ah! They're using that github feature you didn't know about which creates a download without doing all the stuff your carefully crafted workflow does which makes *your* "official" download compile.

There be dragons there. A lot to learn. Slowly getting the hang of it.
Hmm, ta. Might be a bit over the top for a few simple arduino sketches. Nigels link looks interesting. Or just keep everything in one place at Fritzing.
 

laika

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Hmm, ta. Might be a bit over the top for a few simple arduino sketches. Nigels link looks interesting. Or just keep everything in one place at Fritzing.

Not necessarily. My stuff seems to be being used by people I don't personally know who really know how these modern open source development services work and incorrectly presume I do too. If you can get your head round the basics of git as a version control system, stick to the basics and your collaborators aren't wanting you to use all the whizzy bits you should be fine. I've found git itself to be pretty good (hmm, but then I did come direct from sccs, skipping rcs, cvs, subversion and mercurial...) and had been using it for a couple of years using my own server (which I wasn't about to open up to the public). github is more to learn on top of that.

No experience of fritzing but my stuff is software only. I'd say there's a lot of argument for keeping everything in one place if the hardware and software for a boat project are tightly coupled.
 

gregcope

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I am a GitHub fan, a good readme.md goes a long way.

Downloading code is easy and there are already lots of ardunio stuff on GitHub already.

I would encourage you to share as there is loads of possibility of boats stuff on ardunio.
 
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