This article is part of my 1000² Smart Home project. Check out the Architecture and Software and then move on to Hardware. An most importantly, check the Lessons learned and why I did what I did. There are already some first results, connecting all parts of the system.
I have enjoyed building small home automation devices for many years, simple things that make life better or just cater for the lazy animal. The world has been dreaming about the internet of things (IoT) where everything is connected for a while now. While the big guys are focusing on intelligent AI assistants, the market for simple devices is still not mature enough, being full of overpriced products that don’t want to talk to each other. Or, at the other extreme, connected devices nobody seems to find a use for.
This leaves plenty room for DIY projects, which at this point in time can be put together easily thanks to the dropping cost of electronics coupled with multiple open source software packages.
A bit of history
I started to automate things using the traditional computer parallel port and a literal bucket full of relays which drove my thirst to more complicated things that could operate independently. I jumped on to microcontroller projects and a few years later I made a small RS485 network. Moving taught me the important lesson of breaking free of the wires: some devices simply need to be wireless, while the plethora of others could go either way, saving the user from the ugly and complicated cabling experience. This is not an easy job, though.
Is my new ambitious project: do a lot of home automation while spending 1000 euro and 1000 hours working on it. Well, hopefully not that long time, but a budget and time limit give a good motivation to get things going. Plus, both constraints avoid the hobby trap of infinitely fiddling with details.
Some ground rules.
The budget limit is for final parts kept in the system. Failures don’t count, but are great way to learn.
No cheap china: parts used should come from good sources and be of consistent quality, as much as possible.
Distributed intelligence and context aware devices.
Cut corners, where possible.
Attention to security.
Modular hardware: easier to design and debug.
Modular software: easily build a new thing based on old ones.
Separate by function, easy to reconfigure.
Anything that runs on batteries should last at least 1 year in worst case.
Allow room for growth.
More to come….
In Lessons learned and Why I did what I did, I explain the failures, experiences and calculations that lead to the current designs.
The hardware section contains hardware related things.
Software touches the devices’ firmware and control software.