SmartHome

To comply with the contest new checkpoint, I added some details :

• planned improvements in the project log
• almost complete hardware build instuctions (hosted on the project home page)
• software bits / libraries

• Move to Node-RED for the low level part
• Reworkthe bootstrap user interface, according to Node-RED requirements
• Build a new enclosure using some transparent plexiglas (as usual) and add some status RGB leds
• Move the main board to a more powerfull Banana Pi, with a 2.5" SATA hard disk for storage (network cameras images, logs, etc)
• Build more different nodes. I have many different sensors and microcontrollers to try some combinations.
• Add some speaker and a microphone for voice control (microphone is allready onboard on the Banana Pi)

There are still many things to do... But it's very rewarding when everything works as expected...

The system I designed now works well, and I learned a lot doing everything from scratch, from the electronics circuits to the web interface. Sometimes it was very fun, sometimes it was very frustrating. But learning this way was always challenging, and rewarding.

However, I think reinventing the wheel is not a good thing. Some parts of SmartHome could work better if they used some proven sources.

For an example, I want to move the server low-level part to Node-RED project. It will add flexibility ad infinitum, without changing anything to the electronics. Writing python SQL requests from serial input is fun but Node-RED could do it better, with simple scripts.

This way, I could put my ressources in what is really fun for me : low level stuff, designing new nodes and functions, and designing a user interface.

On an other side, the central server would be far more useful with some more robust hardware. The Raspberry Pi misses a real SATA connector, this limits the storage capabilities. I don't wan't to rely on SD-card, network drive or USB hard disk. It also misses some computing power to add some multimedia capabilities.

I want to move to the Banana Pi board, it would be perfect for this use. But the board software is still too young for an intensive use. This is a matter of days/weeks as it's improving very quickly.

Here is the custom shield I built for the SmartHome central station.

Every Raspberry and ATmega328 pins are broken out, 5v and 3v I²C buses were added, the serial communication could be enabled/disabled with some jumpers, there's also a socket for a optional oscillator and a 3.3v LDO regulator (the ATmega328 actually runs on 3.3v / internal 8MHz).

The ATmega part could be reprogrammed directly from the Raspberry Pi, acting like a serial / SPI programmer. Ultimately, it will be possible to edit and reprogram the chip from the web interface.

This board has been especially designed to be built with a perfboard as I have no way to prototype some PCB : 3 weeks wait time is way too much for a prototype, and I don't own (or have access to) a CNC machine.

I'm testing some commands from the station web interface to a prototype wireless node. I'm also testing OOK (low cost on/off outlets) commands near the end.

I'm testing a wireless 2 way security system inside the station web interface.