Non Linear Finite Element Verification Approach for Marman Fitting in Space AIT Operations 2014-01-2268
The marman interface is widely used in space applications to fit the spacecrafts to the launch vehicle and it is the same interface that allows the integration, test and transport of the satellites (AIT). It is usually designed for launch loads with related flight design safety factors and margins, but this is not always compatible with the handling and transport environment. In particular some criticalities are evidenced during the transport of satellites, where they are mounted in the container in horizontal position therefore subjected to bending loads due to gravity and transport dynamic loads.
The study deals with a finite element analysis approach in the calculation and verification of marman clamp bands used for spacecraft AIT operations.
The paper describes the details of modeling of the clamp band parts, the involved spacecraft launch vehicle interface ring and the MGSE interface. All these parts are in contact and this configuration has been modeled adopting the most recent non linear contact analysis techniques.
It is highlighted that the elastic behavior of the parts in contact are determinant for the definition of the limit loads that can be sustained by the structural parts with enough safety margin, evidencing also the limitations of the simple geometric-analytic approach based only on trigonometric formulations with the hypothesis of high stiffness of the interface parts.
Different configurations are investigated in order to determine the contribution to the load sustainability of each involved part structural performance.