The Internet of Cigars

We know, we know. They are bad for you. You shouldn’t start, but some people do love a cigar. And a fine cigar is pretty particular about drying out. That’s why tobacconists and cigar aficionados store their smokes in a humidor. This is anything from a small box to a large closet that maintains a constant humidity. Of course, who could want such a thing these days without having it connected to the Internet?

This fine-looking humidor uses a Raspberry Pi. When the humidity is low, an ultrasonic humidifier adds moisture to the air. If it gets too high, a …read more

Paul Jacob Evans

ESP32 Hamster Wheel Tracker Tweets Workout Stats

Even with all the hamster wheel trackers out there (and on this site) there’s room for improvement. [Bogdan] upgraded his hamster wheel from an Arduino and datalogging shield to an ESP32, and unleashed some new capabilities one does not ordinarily associate with hamster wheels.

[Bogdan]’s project logs distance in feet, duration of current session in time, RPM, overall revolutions, speed in MPH, and overall number of sessions, as well as a couple of system monitoring stats. It also tracks multiple wheels, as [Piontek] (the hamster) has two. However, thanks to the ESP32, [Bogdan]’s wheel tracker tweets its stats and updates …read more

Paul Jacob Evans

Hackaday Prize Entry: LiFePO4wered/Pi+

For some of you the title might seem familiar, as [Patrick Van Oosterwijck] LiFePO4wered/Pi project is a quite successful project. Now he’s designing from scratch the plus version to fill in some gaps and solve some of the challenges that affected the initial project. So what exactly is LiFePO4wered/Pi+ and what can it do?

In a nutshell, it’s a smart UPS for the Raspberry Pi. The standard version allows a Model A+ and Pi Zero to run on battery for over 2 hours, and the B+, B2 and B3 to run for at least an hour (it maybe less, …read more

Paul Jacob Evans

Energy Harvesting Wristwatch Uses a Versatile Photodiode

There’s some interesting technology bundled into this energy harvesting wristwatch. While energy harvesting timepieces (called automatic watches) have been around for nearly 240 years, [bobricius] has used parts and methods that are more easily transferable to other projects.

Unlike early mechanical systems, this design uses the versatile BPW34 PIN photodiode (PDF warning). PIN photodiodes differ from ordinary PN diodes in that there’s a layer of undoped ‘intrinsic’ silicon separating the P and N doped layers. This reduces the utility of the diode as a rectifier, while allowing for higher quantum efficiency and switching speed.

They are typically used in the …read more

Paul Jacob Evans