2015-04-14 According to a press release by the National Institute of Polar Research, Japanese researchers conducted experiments over Antarctica with a Balloon assisted UAV.
A balloon-assisted UAV (Unmanned Aerial Vehicle) named “Phoenix-S1,” developed by Kyushu University and Fukuoka University, Japan, has successfully brought back stratospheric aerosol samples from the altitude of 22 km and observed aerosol density at the altitude of 23 km in Antarctica on January 24, 2015.
The observation was performed as one of the summer activities of the 56th Japanese Antarctic Research Expedition (JARE-56, the leader: Professor Yoshifumi Nogi, NIPR). Phoenix-S1, after launch from an observation site called “S17” on Antarctic continent ice sheet, climbed up being suspended under a rubber balloon while aerosol number density observation and sampling are performed.
After the natural burst of the balloon at an altitude of 23 km, the UAV descended by a parachute, then started gliding back to the surface autonomously by separating the parachute and retrieved at S17 successfully.
The maximum observation altitude this time is unprecedentedly high as the observation altitude using UAVs and even manned aircraft.
This method is quite effective to retrieve observation apparatuses and aerosol samples from upper atmosphere easily at low cost.
The UAV working with the balloon is described as follows:
“Phoenix-S1” is a glider UAV (Unmanned Aerial Vehicle) for the observation of particle number concentration and sample return of aerosols in the upper atmosphere.
The UAV is released from the ground being suspended by a rubber balloon as shown in Fig.1.
It climbs up until the balloon bursts naturally while observing particle number concentration and sampling of aerosols.
After the burst of the balloon, the UAV glides back to the launch point autonomously with the expensive observation apparatuses and precious aerosol samples.
This observation method combining a free balloon and an autonomously gliding UAV was firstly introduced in the summer activity of the 54th Japanese Antarctic Research Expedition (JARE-54), and successfully performed the observation and the sample return up to 10km in altitude (cooperative press release of NIPR, Fukuoka University and Kyushu University, 17th February 2013, in Japanese).
Phoenix-S1 has been developed improving the UAV used in the JARE-54 so that it can cope with the severer environmental conditions at higher altitude.
The UAV was launched from the observation site called “S17” on Antarctic continent ice floor near the Japanese Syowa Station at 6:05 pm (local time) on 24th January 2015. It reached the altitude of 23km at 7km west of S17 approximately one hour after the launch, then the balloon burst naturally.
Phoenix-S1 descended down to 12km in altitude by a parachute, ,and glided back to S17 autonomously after separating the parachute and retrieved at 8:10 pm (local time) successfully.
The collected samples are carried back to Japan for electronic microscopic analyses to observe number concentration and distribution of aerosols.
This is to clarify the process of materials circulation which has close relationship with the several current climatic issues such as global warming and an ozone hole.