Damping Composite Carrying Structures For Future Launchers

Vincent LE GALLO – AIRBUS Defence & Space, Benoit Petitjean & Lionel Zoghaib – AIRBUS Group Innovation

Topic: Vibration Control

Satellites, as payloads of launch vehicles, are connected to the launcher by composite supporting structures. These structures are responsible for the transmission of dynamic excitations generated during the different launch phases, leading to a vibration environment around satellites potentially not friendly to be mastered. One simple way to reduce the payload dynamic environments is to isolate it from the rest of the launcher, by a soft mounting, and/or to damp the vibrations coming from the launcher.

On ARIANE launchers, both strategies are investigated in order to increase the payload comfort, based on Launcher system requirements:

• passive isolation devices to isolate the payload from Solid Rocket Boosters thrust oscillations: this kind of devices can be efficient but introduces some unusual complexities to be managed at launcher level due to the required flexibility,
• damping carrying structures to damp launcher vibrations at the resonance, by integrating damping viscoelastic layers with moderate softness into composite carrying structures.

In this paper, we focus on the damping carrying structures, with a presentation of the concept and an evaluation of associated benefits and drawbacks.