Hybrid system modelling using frequency based substructuring: A case study.

Trucks just like cars and aircraft are designed for a limited lifetime. The truck manufacturer has to ensure no essential components or parts fail during normal service time. Assuring this durability is a very complicated process especially for trucks. Due to thr bie and still increasing ratio of the payload of the cargo to the mass of the load bearing structure, trucks are very sensitive to vibrations, This causes high stresses in the structure and makes the incorporation of dynamics into the fatigue process necessary. The prediction of the global dynamics of the truck is thus extremely important and can be done numerically or experimentally from the moment a prototype becomes available. An 'experimental' optimisation is however not practical because of the man!, possible prototypes of a truck due to the combinations of different cabins, engines. wheel bases, axle configurations... An elegant solution that predicts the global dynamics based on individual numerical or experimental structural models of the different components is necessary for a quick prediction of design changes. In this paper, the 'Frequency Based Substructuring' technique for hybrid coupling is presented and verified on a truck chassis and fuel tank combination. The truck chassis is represented by an experimental model. the empty fuel tank by an experimental or numerical model.