Integration of computer-aided design and analysis: application to multibody vehicle systems

Virtual design and durability investigations are currently performed in automotive industries using three different and incompatible systems: computer-aided design (CAD) system for geometry creation, finite element (FE) software for developing the analysis mesh, and multibody system (MBS) software for automatically generating and numerically solving the differential-algebraic equations (DAE's). This paper proposes a new computer-aided engineering (CAE) approach based on the integration of computer-aided design and analysis (I-CAD-A). The proposed mechanics-based approach achieves seamless geometry/analysis integration, and allows for solid modelling multi-component systems from the outset. The geometrically accurate mechanics-based solid models can be systematically used as the analysis meshes in the small deformation floating frame of reference (FFR) and/or in the large deformation absolute nodal coordinate formulation (ANCF) investigations. In this new approach, ANCF finite elements are used as the basis for creating the geometry for both small and large deformation analyses. In the case of small deformations, ANCF geometry is systematically converted to reduced-order consistent rotation-based formulation (CRBF) FFR mesh, which can be systematically used with standard coordinate reduction techniques to eliminate high-frequency insignificant modes of vibration. The paper discusses the fundamental differences between the proposed method and the isogeometric analysis (IGA) approach and presents illustrative pilot examples to demonstrate the new concepts and the feasibility of developing the mechanics-based design procedure.