Real Time flight data

[rclinks2002]

hello, I am looking for any ideas about a decently priced real time data logger that also does the flight attidute. I have looked at the eagletree systems one, but it did not seem to show the planes attitude in reference to the y axis. It showed control inputs and altitude but no bank angle indication. Please help....

[clolson]

If you are looking for something on a hobby budget, you might consider a cheap gps connected to a radio modem. I think you can get a radio modem pair with decent range in the $200-400 range and a gps in the $100 range. Plug them together with a serial cable and you should be able to capture and monitor the data on your ground station.

That doesn't directly give you attitude and a lot of cheaper gps units only spit out data at 1hz or 0.5hz, but you could compute an attitude based on rate of turn and rate of climb. It would only be a guess but it would be better than nothing. And you could smoothly interpolate positions if you wanted to replay the data later ...

If you want to get a good attitude estimate at a higher data rate, you need to start thinking about IMU's with gyros and accelerometers and such. The raw components aren't all that expensive, but they are really time consuming and difficult to assemble yourself and you need to know a lot of electronics and a lot of higher level math, and there are a lot of issues such as temperature and vibration that can really mess you up if you don't handle them very intelligently ...

If you jump up into the couple thousand dollar range, you can get IMU units that give you a good attitude estimate at high rates. I've used a microbotics MIDG-II ($5000-6000) for a university project and that gave pretty good results. I hope to get access to a Crossbow unav later this winter/spring and that is more in the $2000 range (it also has autopilot features which is cool, it is more than just a passive sensor unit.)

I see the UAV world only through a very small peephole, so I'm sure others can share different and better ideas than I have.

Regards,

Curt.