Development and validation of a simulation methodology to analyse mechanical systems moving on flexible bodies

The aim of this paper was the identification of the load conditions to consider during the design and assessment of military vehicles. This meant identifying test tracks and their corresponding ground speeds and track lengths, and to define their combinations that are useful to simulate the load spectrum representing the system/component life in an accelerated way. The result of this activity was the development of a formulation for the synthesis of a single power spectrum density function (PSD) representing multiple load conditions expressed by a set of PSD functions. This function is equivalent in terms of damage to the given PSD functions set. Another important result was the definition of a virtual test ring, equivalent to those defined in standards for equipment and supplies, but useful for the virtual check of the military vehicle integrity. This new formulation and the proposed test ring intend to supply tools that would be very useful in the early phases of vehicle design and assessment. In order to verify these results, numerical and experimental analyses of a generic military vehicle were undertaken. Results demonstrated the validity of the load synthesis formulation and the load combination that are useful for the assessment of military vehicle durability. KEYWORDS: Fatigue, Accelerated durability tests, Military vehicles, Multibody simulation