City Vehicle XAM 2.0: Design and Optimization of the Composite Suspension System 2014-01-1050
The use of composite materials is very important in automotive field to meet the European emission and consumption standards set for 2020. The most important challenge is to apply composite materials in structural applications not only in racing vehicles or supercars, but also in mass-production vehicles.
In this paper is presented a real case study, that is the suspension wishbone arm (with convergence tie and pull-rod system) of the XAM 2.0 urban vehicle prototype, that it has the particular characteristics that of the front and rear, and left and right suspension system has the same geometry. The starting point has been an existing solution made in aluminum to manufacture a composite one.
The first step was the development of a dynamic model of the vehicle to understand the suspension loads and to define the suspension weight and stiffness target with respect to the solution made on aluminum, because it was necessary to understand the tensile strain on the component to simplify and optimize the geometry. Once the wishbones external surfaces have been defined, a composite layer thickness and orientation optimization have been made to define the lamination lay-out. After the analysis of the composite thickness optimization results, a new CAD model, that encounters the process constrains, was build up and finally the lamination process was defined.
The results were a weight reduction of 9% and an implementation of stiffness of 38%.