Development of a shape-memory alloy satellite antenna that could self-deploy with the heat of the Sun is under way at the University of Bristol in the UK.
The material selection and detailed antenna design work follows the successful test of a prototype SMA actuator in November 2004. Aspects of the prototype actuator’s design and some of its component materials are not suitable for the harsh environment of space. However, the core of the SMA actuator, which is a honeycomb-like chiral structure, is suitable for space. The chiral structure gives the actuator a negative Poisson ratio. This negative ratio means the structure does not get thinner as it is stretched or wider as it is compressed.
“The [chiral] structure could also be used as a core for a sandwich structure for damping or for crashworthiness,” says University of Bristol aerospace department senior lecturer Fabrizio Scarpa.
The antenna’s development is part of a three-year, $200,000 negative Poisson ratio materials project, which began in 2004. It is being funded by the US Army’s research office.
The project’s prime contractor is the Atlanta-based Georgia Institute of Technology. The self-deploying antenna is only one of the applications being investigated under the US Army project.
Source: Flight International