20 | June | 2014 | brainwagon

In my previous article pondering sensors for my garden, I shamefully neglected a viable and interesting choice, the JeeNode JeeNode is available here in the U.S. from Modern Device. It’s sold as a kit, which is unusual, but not particularly scary to assemble. It’s just a few through hole parts. It’s a pretty bare bones processor, but does interestingly include a wireless module. It uses the RFM12B modules running on either 433 or 915 Mhz. But what really makes the JeeNodes interesting to me are that they abandoned the (I submit) broken shield model of Arduino shields, and instead group the output pins for the Arduino into a collection of identical Ports which can be accessed using their JeeLib library. Each port consists of six pins (one ground, one Vcc, and four data pins) and all can be used to implement an I2C bus in software to access peripherals. Very cute, and much nicer than the hodge podge of existing code for the Arduinos.

But the website at JeeLabs has a bunch of other cool stuff. Like details on one of their JeeNodes that’s been transmitting data wirelessly for over eight months, powered by just a coin cell. Or this Dive Into JeeNodes which is a tutorial on interfacing JeeNodes to a Raspberry Pi to make a house monitoring system. While the blog isn’t being updated anymore, it includes all sorts of good stuff, including this rather clever article on VCC Measurement (a software only way for an Arduino to determine it’s own input voltage). Great stuff.

Building my full sized quadcopter is going rather slowly (sigh) but in the mean time I picked up a little Hubsan X4 to play with. It’s cheap, and because it has a very low mass, it’s pretty hard to destroy. After more crashes than I can count, I’ve only managed to ding up one propeller (and replacements are pretty cheap and easy to get). But I must admit that one of the reasons I’m interested in quads and RC vehicles is to shoot video from them. While it is possible to get microquads that carry cameras, or even allow FPV, I kind of like the idea of home brewing something. Often, such projects are aided by following in the footsteps of giants, looking at how others have solved problems helps a bunch. It’s also inspiring. That’s why I was particularly enthused to find this article:

Build a micro-sized first-person-view quadcopter

A couple of things I like about the article:

It suggested the Vitality H36 quadcopter. It has one really interesting feature: it’s compatible with the Flyky/Turnigy radio transmitters. It would be cool to use my big transmitter with the tiny quad.
Provides good hints on the video camera, transmitter and receiver module that you might want to use.
Good links to circularly polarized antenna construction details.
It’s an existence proof that it can be done! Awesome!

It looks like a complete hoot!