Solar panels for sensor nodes

Intro For a while now, I started replacing the dead AA(A) batteries in my sensor nodes with rechargeable NiMH ones. So, since these batteries are rechargeable, I thought, why not trying adding small solar panels for sensor nodes, where light is abundant. Node 27: outside sensor Purpose: outside temperature, humidity, light, pressure sensor. Powered by 2 x AAA 500mAh from Ikea. The solar cell is rated 3V, 125mA and is pointing vertically south and costs… Continue reading

Stop it with the coin cells!

Hey companies making sensors and remotes! (for smart home/home automation and the likes). If you can make a sensor microscopic – fine If it needs to be portable – fine But if it is rather small, but still visible you are not doing anyone any favor by making it as small as possible with a coin cell battery that runs just a few months or even less. If your sensor can run for years and… Continue reading

Fast 3D printed boxes

Intro Finding the proper box for my sensors is not easy. But even after finding one that mostly worked, I wanted to explore more sensors and still have a bit of freedom while doing that. Of course, that means 3D printing with the new 3D printer. There is just one problem …. 3D printed boxes take a long time to 3D print. An example Here is the newest sensor module I designed, which can fit… Continue reading

10002 Server

Intro In my initial thoughts about the smart home system architecture, the server was most likely a raspberry pi: At that time it seemed the PI was apt for it. And a raspberry pi 2 served me well for a while, and then I moved to a pi 3 and everything was good. Until it was not enough… What happened? I had mosquitto and node-red as the main things running. And I added some simple… Continue reading

10002 I2C connectors

Intro In my first iteration of sensors I relied on wire connections between sensors and the actual node board. The result for a motion sensor and a temperature and humidity sensor looks like this The problem with that is that during sensor modules assembly run I spend quite a bit of time on the wiring. On top of that, the result is a mess of small wires inside a box. It makes it hard to… Continue reading

10002 Zen

Zen At some point I though about building the smallest PCB for a sensor node that I could. Hence, the ZEN was born. The PCB is small enough to fit on a holder of 2 AA batteries. Where I have only build a few of these. Here is one reading the soil moisture sensor on basil. Here is another one chilling in the fridge, reading a temperature sensor. And here is one replacing the alarm… Continue reading

10002 Short assembly run no 2

Intro It is quite clear that my smart home project is going quite slow and erratic. Following the other assembly, I made another batch of 5 sensor nodes. These are meant to use the new soil sensors, once they arrive. Since plants will be both outside and inside and we are talking about rain and water, the sensors will go into waterproof boxes, with the soil sensor connected via a cable. So, this assembly is due… Continue reading

10002 Motion sensors?

Motion sensor madness Picking the right one for my smart home project is not trivial. From left to right – Osram Nightlux, Ikea Molgan, Ebay sensors with sensitivity and timing adjusment (BISS001), smaller ebay sensor with no adjustment, another ebay sensor. As you can see I have looked at 2 different options: use a ready made sensor and fit it with a radio, or build my own. Ikea Molgan I hacked one a while ago –… Continue reading

10002 Progress

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. Progress Finally, enough pieces of the puzzle are starting to fit together in my Smart Home project, so that I can have some end to end functionality: press a button here… Continue reading

10002 Architecture and Software

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. Starting with a top down approach – what the system should do, it soon became clear that some devices will be custom and some will be off the shelf. Determining… Continue reading