Inflatable structures have emerged in the last few decades as a potential solution to the problem of launch vehicle and satellite payload size restrictions. Inflatable technology may present a superior solution compared to other mechanisms. A notable achievement in this area was the successful deployment of the Inflatable Antenna Experiment from the Space Shuttle in 1996.
Inflatables are also being proposed for manned space habitats. The Bigelow Expandable Activity Module is set to be launched on a Space-X ISS resupply mission on Friday 08 April. It will remain attached to the ISS for a two-year evaluation mission. Bigelow is also developing larger modules which can be used in space or on the surface of the Moon or Mars.
The Prototype Inflatable Conical Antenna REXUS Deployment (PICARD) experiment has been designed to investigate the deployment, rigidisation and functionality of an inflatable antenna. Inflatables have the potential to provide electrically large antennas on very small satellites such as cubesats.
CAD diagram of antenna and deployment system
In particular, PICARD prototypes a wideband antenna that can be used for P-band (250 to 500 MHz) sounding of the Earth’s ionosphere. It also provides a demonstration of a novel method for maintaining the inflatable’s shape after the inflation has been completed, whereby the antenna elements themselves are used to strain rigidise the structure.
The newly formed Space Environment and Radio Engineering (SERENE) group at the University of Birmingham has achieved its first sub-orbital rocket flight. An experimental inflatable antenna was launched as part of this year’s REXUS (Rocket EXperiments for University Students) programme in a joint project with the University of Strathclyde.
The REXUS programme allows university students from across Europe to launch experiments into space on a sub-orbital sounding rocket. The rockets are launched from the Esrange Space Center in Kiruna, Sweden and they allow students to conduct practical demonstrations of their space research. The student team travelled to Sweden on Monday 07 March and PICARD flew on REXUS 19 which launched at 06:10 on Friday 18 March. The flight reached 78 km altitude and provided approximately one and a half minutes of microgravity during which time the antenna was successfully deployed and tested. The antenna was then ejected from the main rocket to avoid any potential interference with the re-entry parachute system.
More information is available on the Successful flights for student experiments website.
Notes:
SERENE is supported by a Chair that has been co-sponsored by DSTL and the Royal Academy of Engineering.
The REXUS programme is undertaken under a bilateral Agency Agreement between the German Aerospace Center (DLR) and the Swedish National Space Board (SNSB). The Swedish share of the payload has been made available to students from other European countries through a collaboration with the European Space Agency (ESA).