SPOT + EE = SPOTEE: SPOT Hardware Development

Some of us at the Labs have taken-on a project of making a high-altitude weather balloon after-hours. Up until now, we are progressing rapidly and we should be able to meet our launch date of April 5th. The objectives of the project are:

• Have loads of fun working on an hobby engineering project
• Provide examples of custom hardware design and software drivers for the Sun(tm) SPOT platform
• Gather data (pictures, atmospheric pressure, temperature, GPS coordinates and altitude)
• Document the whole endeavor and have an Open Source project around it

We have started a Java.net project for code and hardware and a wiki for info. Our mailing list is also available for up-to-the-minute coverage :)

The payload will consist of the following:

• GPS+GSM Module (Telit GM862-GPS) with antennas
• MicroTrak 8000FA APRS tracking transmitter
  
• SPOT with custom electronics for payload control
• Olympus FE115 digital camera
• Honeywell absolute pressure sensor w/ signal conditionning and LTC2415 24-bit Sigma-Delta ADC
• Diode-based temperature probe connected to an ADT7411 (eDEMO board ADC)
  
• 2x Energizer e² batteries for camera
  
• 3.7V 6000mAh Li Ion battery for the GPS
• 9.6V 2000mAh NiMH battery for the tracking radio
  

We will be using a Kaymount 600g balloon with 450g of free lift. Our preliminary launch site is around Watsonville, CA. We would try to control the payload cut-off point so that with prevailing winds we arrive in the Central valley between Merced,CA and Fresno,CA. According to some initial calculations, this would put us at a max altitude of around 50,000 feet (15.2km) and a travel distance of around 85mi (137km)

Right now, most of the material has been acquired or ordered (balloon, parts, radios, parachute, hardware) and the electronic design is completed. Everything to date will be committed to the SVN as soon as the project gets approved on the java.net site.

In the meantime, here are some pictures of PCBs and parts we have:

 

Batteries and tracking radio 

 

eBALLOON Board and GSM/GPS module carrier board

Olympus FE115 camera body, stripped of its case

If you have interest in this project, feel free to visit the wiki and contact us on the mailing list. We would need some Amateur Radio operators would would be willing to help in tracking the balloon using APRS :) I'll keep you posted on the developments over the next days.