Of energy and foam

Continuing with the final three projects which drew our attention at the DGA 2016 Innovation Days: Sésame II and Operasol, both shown on the propulsion/energy stand, and Batolus, shown on the materials stand.

Today’s soldier carries a lot of electronic equipment which all needs to

The fuel cell battery fits neatly into a small pouch

The fuel cell battery fits neatly into a small pouch

be powered. In order to make him more comfortable and give him greater autonomy, the French DGA procurement agency is constantly seeking ways to lighten the soldier’s load. Sésame II (sources d’énergie pour systèmes autonomes miniaturisés or energy sources for autonomous miniaturised systems) was launched with this in mind. The project, undertaken by Safran Electronics & Defense in partnership with the CEA (French Alternative Energies and Atomic Energy Commission) Liten looked at replacing the metal-based batteries currently used with fuel cell batteries which work using hydrogen and oxygen. The innovation lies with the hydrogen being supplied in a cartridge filled with liquid. This technology provides the same energy as a traditional battery but is twice as light. In concrete terms that means that for three days of energy autonomy the soldier will have 2kg less to carry. To charge the battery all he has to do is change the cartridge which, like the battery itself, is recyclable.

Seeking to provide energy on a much bigger scale, Operasol (which doesn’t seem to be an acronym for anything that we could discover!), developed by small company C2A in partnership with the CEA, is an ultralight solar panel, 70% lighter than a standard solar panel but providing equal performance of 150W/m². Made out of composite materials (3.8kg/m²), these solar panels are only 14mm thick, are more rigid than current ones and are 100% adaptable to user requirements.

Operasol will be available from 2017 for both military and civilian applications to be installed on light infrastructures (tents, field hospitals etc.) but also on cars, satellites, remotely piloted air systems (RPASs) traffic signals and so on. These innovative solar panels have already passed the challenging International Electrotechnical Commission (IEC) tests which are a reference in more than 100 countries.

The solar panels on a tent at the Canjuers Training Ground in southern France (photo credit: 2CA)

The solar panels on a tent at the Canjuers Training Ground in southern France (photo credit: C2A)


In a completely different sector, Batolus (battle damage tolerance for lightweight UAV structures) is an absorbent foam to line RPAS fuel tanks to make them less likely to explode should they be hit by bullets. Developed by Airbus Defence & Space (incidentally at the Suresnes research centre which Airbus announced this week was to be closed) in partnership with ONERA and the CEA as part of a five year European Defence Agency project (2009-14) and in collaboration with colleagues from Germany, Great Britain and Sweden, the team developed a demonstrator for RPAS fuel tanks. The foam proved that it provides protection from isolated 12.7mm bullets when the RPAS is flying under its cruising altitude and during take-off and landing, enabling the aircraft to land even if it has been shot. The concept is applicable to any type of aircraft or ground vehicle fuel tanks in both military and civilian sectors.