In teaching a class, one should know the subject. I have been teaching the balloon class (AOSS 584) for a few years now. We have launched something like 12 balloons in class. But, I have never actually built a balloon myself. The reason for this is because I have never tried. So, the obvious question then is, what do you teach the students? Well, nothing. The general idea of a master’s level class, or even a senior level engineering class, is that the student should know how to get enough information on their own to be able to do things on their own. They work in teams that are ~carefully~ chosen to have some diversity of talents on the team. So, while not all members will know how to do all things, the team, as a whole, should be complete enough to build a system. My role is a facilitator – I help them debug systems, drive them to complete the project, and offer guidance. Until this year, I have never done the project myself.
But, I decided that I should actually try to do this myself, since it is unfair that I don’t have to experience the challenges that the students have to experience. So, the GSI of the class and I have teamed up to create the “Fail Balloon”. We named it to lower people’s expectations. Here is a brief rundown of our system:
- Microprocessor – Arduino Nano
- Communication – AeroComm 900 MHz radios
- GPS – Inventek ISM300F2
- A Datalogger with a USB thumb drive
- Two temperature sensors, a humidity and pressure sensor and a three-axis accelerometer
- Two cameras (horizontal and vertical)
- Xbee to wirelessly communicate to our flight termination unit (FTU).
- FTU – Ardunino nano with XBee. Arduino will have a timer also and two independent cut-down lines.
So far, we have a board that we can mount most of our hardware (sort of). I have gotten the Arduino to talk to the datalogger (a week or so ago) and the GPS (last night). All of the sensors are working and can write data to the datalogger (through the Arduino, of course). I also got the Arduino to record the GPS data on the datalogger. I have a circuit working to turn the cameras on and off and to take pictures when I tell it to. So, a fair bit done. But, if you are keeping score, we only have two weeks of the semester left, and we still have a long way to go.
Just to prove that some of this is actually true, here is a plot of the GPS position on my drive to work this morning. The data was recorded on the datalogger, and I plotted it when I got to work.
More updates as they happen.