My latest project (now I have some spare time again!) has been something quite simple – I’m terrible at putting the washing machine on, and then forgetting about it for the rest of the day, leaving a load of wet clothes inside to fester for hours on end. I know some washers and dryers come with alarms that beep at you when they’re finished, and I wanted to emulate this with an Internet of Things vibe.
So I came up with the Raspberry Shake – quite simply it’s an accelerometer connected up to a Raspberry Pi Zero with some LEDs to indicate status, all shoved inside a small box with some magnets attached, so it can cling to the side of any appliance. The Pi Zero runs a bit of Python code that checks for any movement, and sends notifications when the appliance starts and stops. I’ve made two so far, with plans for a third, and they’re working great!
You can see a full writeup and a video of the build on the Raspberry Shake project page
For my latest project (details
coming soon available here) I acquired a couple of LIS3DH triple-axis accelerometers. As most of the products available through Adafruit are fairly well used, I didn’t bother checking what libraries were available before buying, but unfortunately for me only a C++ library had been written. I didn’t feel like learning C just for the purpose of this project, and so the only option left was to write my own Python library!
Thankfully I had some excellent starting points with the aforementioned C++ library, as well as the Python I2C library that Adafruit have published. I found myself referring back to the manufacturer datasheet quite often as well, mainly to clarify what each register contained.
While the task initially looked rather daunting (having had zero prior experience with bit-bashing through registers) – I found that with some pre-existing code to crib from, the various functions took shape rather quickly, and within an afternoon I’d produced a library exposing all the basic functions I’m likely to need for this project. I’ve put my code on Github in the hope that people will contribute to filling in the gaps, and improving where necessary.