Hello all,
Just wanted to report that we had a great flight last sunday. Here's a
recap and some more details on our payloads.
We launched from a slightly more southern position than last time.
Predictor said otherwise we'd end up in one of several large bodies of
water (big rivers and estuaries mostly). Measuring necklift was a tad
tricky due to gusts of wind, but turned out ok. Launch was made
interesting by the camera platform (see pics) being the last in the
train, and the balloon was being blown somewhat sideways by the wind.
The triangular camera platform worked fairly well. There were no
pictures of the sun :), and although it did turn and wobble a bit, it
certainly wasn't as bad as when using a single small payload box. The
video is actually watchable without getting ill. :) We had both the
stills and the video pointing slightly downwards as we wanted more
ground detail than sky detail, this also worked fairly well. We also
used 2 ball bearing swivels (the fishing kind) between the balloon and
parachute and parachute and lower payloads. In this way any turning of
the balloon or parachute would not induce turning of the payloads.
The triangle is made of fiberglass tubes (the kind found in kites) and
we had a box at each corner. On 2 corners of the triangle we had the
video and stills camera. On the 3rd corner we had the science payload;
that's the box with the smiley. The 2 eyes are the UV sensors, one
with a filter to be able to differentiate some frequencies. It also
had a 9-DOF IMU on board (3-degree accellerometer, 3-degree
compass/magnetic field, and 3-degree gyroscope); the board also had a
BMP-085 pressure sensor on it.
Chase was fun. The predictor on the tracker showed 1 area for a long
time, but after burst it moved about 25km southeast, no idea why. If
anyone can elaborate, that'd be great.
As was seen on the livestream, the payload landed in several low
trees, we were able to get it out by pulling on the lines and we had
gear with us (pole with a hook) and got everything out.
Images from the flight can be found here:
http://imgur.com/a/Jnktr
We're looking into integrating/overlaying the flight data into the
video, this is going to take some more time; I'll post it when we have
it available. Unfortunately the GoPro stopped filming before burst due
to the battery running out. We didn't have enough time to make an
external battery pack for the gopro and the batteries needed would
have significantly increased the payload weight.
Also the science data from the 9-DOF IMU and UV and electromagentic
field strength measuring device are still being processed and
interpreted. Will also give a shoutout when that's done.
Some statistics from the day:
* Balloon: Hwoyee 1200
* Payload train weight: 810g
* Necklift: 2000g
* Max altitude reached: 34060m
* Time at launch: 09:34:51 UTC
* Time at landing: 12:20:53 UTC
* Flight time: 2 hours 46 minutes
* Pictures taken: 4023 on the Canon A480 with CHDK
* Video: 14GB of HD footage on the GoPro Hero HD
* 3G data sent through livestream: 500MB.
Thanks to all those who listened in.
Cheers,
Costyn.