The build starts with an old alarm clock. The clockwork internals are removed, but the bells remain, powered instead by a brushed DC motor. An Arduino Nano is the brains of the operation, interfacing with the now-ubiquitous temperature, humidity and barometric pressure sensors. Time is displayed on a Nokia 5110 LCD screen of the type popular a decade ago when options for small hobby project displays were significantly more limited then they are today.
As a nice touch, an old circuit board lends a new face to this clock, with a trio of big chunky buttons to act as controls. The LCD uses attractive icons to help convey information, making the most of the graphical capabilities available. There’s even a rudimentary weather forecasting algorithm that uses barometric pressure changes to predict the likelihood of rain.
Calling it the ESPecter, [ACROBOTIC Industries] wanted to make this a simple project for anyone, regardless of skill with a soldering iron or Arduino toolkit. So they decided to base the guts on common components that can be put together easily, specifically a Wemos Mini D1 with an OLED shield as a bright display. They also designed a cool tiltable 3D-printed enclosure for this small device so that you can orient it to your eye level.
For our Northern Hemisphere readers the chill winds of winter are fast approaching, so it seems appropriate to feature a weather station project. Enjoy your summer, Southern readers!
[Fandonov] has created a weather station project with an Arduino Uno at its heart and a Waveshare e-ink display as its face to the world, and as its write-up (PDF) describes, it provides an insight into both some of the quirks of these displays, and into weather forecasting algorithms.
The hardware follows a straightforward formula, aside from Arduino and display it boasts an Adafruit sensor board and a hardware clock. Software-wise though there are some tricks to give the display a scalable font that other tinkerers might find useful, drawing characters as a matrix of filled circle primitives.
The write-up gives an introduction to forecasting based only on local readings rather than on the huge volumes of data over a wide area used by professional meteorologists. In play here is the Zambretti algorithm, which takes the readings and information about whether they are rising or falling, and returns a forecast from a look-up table.
As we’ll all be aware, even professional weather forecasting is fraught with inaccuracies, but this is nonetheless an interesting project that is very much worth a second look. Meanwhile we’ve covered huge numbers of weather stations in the past, a couple of interesting ones are this one using a classic TI99/4A home computer, and more relevant here, this one using an e-paper badge.