Comparative Analysis of THUMS Versions for Safety Applications

This study presents a comparative analysis of the Toyota Human Model for Safety (THUMS) in its three latest versions—Version 4, Version 5, and Version 6—using finite element simulations in LS-DYNA. The objective is to evaluate key differences in anatomical accuracy, injury prediction capability, and computational efficiency across these versions. Version 4 offers a highly detailed anatomical structure, including internal organs, which enhances injury analysis. Version 5 introduces active muscle modeling, enabling the simulation of pre-impact occupant postures. Version 6 integrates both features, combining detailed anatomy with muscle activation capabilities for a more advanced human body representation. To assess these differences, three simulation scenarios were developed, examining frontal sled impacts, falls from seated positions, and falls from standing positions. Beyond automotive crash scenarios, this study also explores the applicability of THUMS in non-automotive safety contexts, such as injury prevention in everyday life. The findings highlight the importance of integrating advanced biomechanical modeling techniques to improve injury prediction and safety assessments. The continued refinement of THUMS is essential for enhancing virtual human body models used in crash simulations and injury prevention research.