Project
For this year’s edition (2021), we are specializing in measuring the passage of UV radiation through artificial and authentic human skin samples.
The secondary objective of our experiment is to measure and store the height, pressure, temperature, GPS, relative airspeed, etc.
Weather Station
Most of the measurements can be made by small electrical components but to determine the relative windspeed (=wind flow speed) we have had to construct an anemometer. We have designed and 3D printed the anemometer’s body and its hemispherical cups. Wind will cause the cups to rotate as a result of the difference in air resistance being larger on the hollow side in comparison to the spherical side.
Radio Communication
We want to transmit those data points to the ground receivers by making use of RTTY and APRS. We have succesfully completed field work and radio tests with both modules working at the same time.
The tests showed us that we can reliably receive GPS coordinates and general information such as battery voltage, etc.
Launch
On April 21, the day before the launch we presented our project to the other school via a teleconference. During this teleconference, we got to know the projects of the other schools and listened to a lecture on the life cycle of stars explained by Dominic Bowman. After the presentation of the projects by the various groups, which also included Spanish and British students, the schedule of the next day was gone through.
Launch Day
On Thursday, 22 April, we were the only school allowed to take part in the balloon recovery. We left around 8:45 from Dilsen to the Koninklijk Meteorologisch Instituut located in Uccle. There, we would pick up the GPS signals that our RTTY and APRS system would transmit in order to try to determine the location of the balloon in flight. At 11:55 balloon-A containing our weather station and the experiment was launched, shortly followed by balloon-B at 12:11 which contained our GPS systems. Shortly after launching balloon-B, we picked up an RTTY signal, northerly winds caused the balloon to be blown towards Wallonia. After driving a few minutes through Brussels to get to the highway we lost the RTTY signal. Follow car 2 still received a weak signal but after a few minutes, the signal was definitely lost.
After this, we tried to pick up the signal with a yagi antenna but all attempts were in vain. After about an hour we received a coordinate of the landing of balloon-A, Dirk Geeroms had sent a GPS tracker with balloon-A to find it back. We found the balloon in a village called Salet, about 20 kilometers from the French border. Erik Schrijvers the organiser of Asgard found balloon-B seven kilometres from Salet. Once we had recovered the two balloons, the data analysis for all the different groups could start.
Results