An integrated software framework for conceptual design of vehicle body structure based on isogeometric analysis

Conceptual design represents a critical stage in vehicle body development, which aims to establish the overall structural framework and ensure that key performance indicators are satisfied. In this study, an isogeometric analysis (IGA)-driven body performance evaluation method is presented to facilitate the optimization of conceptual vehicle bodies. Based on this approach, a conceptual vehicle body design software that integrates parametric modeling, linear structural analysis, and cross-sectional size optimization is developed. By employing IGA for the analysis of beam, joint, and shell structures, key performance indicators such as bending and torsional stiffness can be efficiently evaluated without the need for a labor-intensive mesh generation process. The optimization framework is formulated with stiffness constraints and aims to minimize the total mass, utilizing the Method of Moving Asymptotes (MMA) to optimize cross-sectional dimensions and panel thicknesses. Furthermore, a multi-body collaborative optimization framework is established to account for the constraint of shared components among different vehicle bodies. Numerical examples demonstrate that both single-body optimization and multi-body collaborative optimization achieve a weight reduction of over 15% while satisfying performance requirements. The integration of these modules substantially streamlines the iterative workflow between CAD, CAE, and optimization environments, thereby providing an efficient and practical tool for rapid lightweight conceptual design in vehicle body development.