Design and Crash Safety Assessment of an Autonomous Electric Minibus Superstructure

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Published: Sep 26, 2026
Keywords:
Autonomous electric minibus Superstructure design Side-impact performance Pedestrian safety Finite element analysis

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W. Usawiroj
Department of Mechanical Engineering, Faculty of Engineering, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand
T. Limcharoen
Department of Mechanical Engineering, Faculty of Engineering, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand
P. Damchuen
Department of Mechanical Engineering, Faculty of Engineering, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand
K. Ruangjirakit
Department of Mechanical Engineering, Faculty of Engineering, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand / Future Automotive Structure Research Group (FASt), Mobility and Vehicle Technology Research Center, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand
P. Jongpradist
Department of Mechanical Engineering, Faculty of Engineering, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand / Future Automotive Structure Research Group (FASt), Mobility and Vehicle Technology Research Center, King Mongkut’s University of Technology Thonburi, Bangkok, 10140, Thailand

Abstract

This study presents the structural design and crash safety assessment of an autonomous electric minibus superstructure. A systematic approach combining material selection with simulation-based refinement enabled a balance of safety, efficiency, and manufacturability. ASTM A36 steel was selected for its favorable mechanical and practical properties. Targeted reinforcement of door pillars and floor cross-members improved lateral-impact resistance, reducing displacement by 65.9%, while front-end geometry adjustments enhanced pedestrian protection, keeping HIC and chest accelerations within safety limits. The final design also achieved a 7.7% reduction in structural mass without compromising integrity. These results demonstrate that combining material-informed design with parametric safety evaluation can guide the development of autonomous minibuses that are both safe and efficient for low-speed urban environments.

Article Details

How to Cite
Usawiroj, W., Limcharoen, T., Damchuen , P., Ruangjirakit, K., & Jongpradist, P. (2026). Design and Crash Safety Assessment of an Autonomous Electric Minibus Superstructure. Journal of Research and Applications in Mechanical Engineering, 14(3), JRAME–26. retrieved from https://ph01.tci-thaijo.org/index.php/jrame/article/view/264474
Issue
Vol. 14 No. 3 (2026)
Section
RESEARCH ARTICLES
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