The heart of this system is an Arduino compatible JeeNode micro-controller designed by Jean-Claude Wippler from the Netherlands (http://jeelabs.org/
). It contains an Atmel Atmega 328P, which has more memory and runs faster than my first computer (a Sinclair ZX-81). The JeeNode has a significantly smaller footprint than a standard Arduino, similar to Lady Ada’s Boarduino, but also has an integrated Hope RM12B wireless module. Additionally, the JeeNode has the I/O pins grouped in to four “Ports” to facilitate standardizing sensor connections, and runs at 3.3V. JeeLabs has developed a number of sensor/breakout boards, called "Plugs" using the IC2 interface, meaning they can be piggybacked on to the same port, making the JeeNode extremely extendable. In addition to the hardware, JeeLabs provides a software library making the use of ports and assessing sensor data very easy.
I used the following hardware, available in the U.S. from Modern Device (http://shop.moderndevice.com/
) or elsewhere from JeeLabs (http://jeelabs.com/
*JeeNode Kit ($22.50) (a.k.a. “Transmitter”)
*JeeLink Module ($36.50, assembled) (a.k.a. “Receiver”)
*JeeLabs Pressure Plug ($21.95) Bosch BMP085 barometric pressure and temperature sensor.
*USB BUB Board Kit ($14.00) or FTDI programming cable
*JeeLabs Gravity Plug ($20.00) BMA020 3-axis accelerometer sensor
*JeeLabs Memory Plug ($9.50) (1 x 128KB STMicroelectronics M24M01 EEPROM)
For the full setup, you are in for about $125 + shipping. You could fly with just a Pressure Plug for altitude. You will also need batteries and a holder (I got mine at RadioShack). Consider this a small investment in your continuing Maker education. You only need one JeeLink and USB BUB. You can add or reuse as many JeeNodes as projects you dream up (or just type “Arduino” in the Instructables search box). The sensors and Port library can also be used with a standard Arduino with some effort.
I do not work for or have financial interest in JeeLabs. In fact, I would have a hard time pointing to the Netherlands on a map. I have, however, worked with Jean-Claude’s tech and find it well engineered, documented, and supported. Those are three requirements to get my hard earned money in my pursuit of hobby. I hope this sends more his way.
Each of the kits have instructions online and require some soldering. The sensors need headers soldered depending on how you position them. If you are unsure of your soldering skill, check out http://www.instructables.com/id/How-to-solder/
. If you want to see what building the kit involves, check out http://jeelabs.org/2010/09/26/assembling-the-jeenode-v5/
. Once you build this, you can definitely claim you can solder. Hacking is all about mad skills.
In my hardware configuration for the Transmitter, all the IC2 sensors are connected to Port 3, and I have a single LED and resistor hooked to the Port 4 digital & GND lines. Any variation from this layout can be easily accounted for in the Transmitter program by changing the Port numbers. I’m powering the JeeNode using 2 x AA in a plastic RadioShack battery holder. The flight assembly weighs in at about 50g, of which a little less than half is battery. A light-weight lithium ion battery would be ideal for this, but because of the near constant radio operation, it would take a bit more than a CR2032 coin cell (yes, I tried).