Italsat, Sax and Tethered Satellite System
static and dynamic analyses.

 

The analyses belong to the same kind of components of three different projects:

·    Italsat communications satellite.

·    Sax satellite for X-ray astronomy.

·    Tethered Satellite System (TSS), a joint experiment of ASI (Italian Space Agency) and NASA which flew two times with the NSTS Space Shuttle.

 

The structures to be analyzed were:

·    The piping of all branches of the propulsion system.

·    The supports of pipes and propulsion components (thrusters, valves, pressure regulators, transducers, filters).

 

This type of structural assembly must exhibit a sufficient stiffness (a minimum natural frequency is required) but a proper flexibility in order to withstand the thermal environment without exceeding the allowable stresses of the material. To obtain that, the location and the type of supports and the shape of the pipe line must be optimized. The loads involved in these space structures are essentially as follows:

·     Pressure.

·    Temperature.

·    Static accelerations.

·    Sinusoidal and random vibration loads due to launch/reentry phases, road and air transportation, handling, acceptance testings.

 

The type of analyses performed are generally static, modal, frequency response and random. For the Tethered System a fail safe fatigue analysis was required (which is mandatory for payloads using the NSTS).