A Lightweight Body Frame Conceptual Design of a Mini Electric Vehicle

Abstract:

To realize the lightweight structure, a car body frame conceptual design of a mini electric vehicle was performed with topology optimization and size optimization. Topology optimization was used to search load paths and size optimization was applied to model a simplified structure. Static stiffness, crash safety and free vibration conditions were considered simultaneously in both of the optimization phases. Due to the feature of conceptual design, crashworthiness cases were regarded as static stiffness ones with inertia relief analysis for a linear equivalent. The objective function in multi-objective topology optimization was defined by Compromise Programming Method in OptiStruct. Because of the characteristic of the geometry and the manufacturing constraints of profiles, the design variables in size optimization were defined as both continuous and discrete variables. The resultant structure outperforms the original one in many structure responses and most significantly, it reduces weight by 36%, which demonstrates the efficiency of the proposed method.

• Periodical: Advanced Materials Research (Volume 952)
• Pages: 223-226
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.952.223
• Online since: May 2014
• Authors: Da Feng Jin*, Xiao Qi Chen
• Keywords: Car Body Frame, Light Weight, Mini Electric Vehicle Design, Size Optimization, Topology Optimization

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