Parametric Design Optimization of Inner Chassis Retarder Bracket Using Finite Element Analysis

The inner chassis retarder bracket is a critical load-bearing component in heavy-duty vehicles, responsible for transferring braking loads from the retarder system to the main chassis. Despite its structural importance, studies focusing on the optimization of this specific bracket remain limited, with most existing research addressing generic mounting brackets or employing global topology optimization. This study presents a focused parametric design optimization of a right-side inner chassis retarder bracket using the Finite Element Method (FEM) to enhance structural safety and reliability. Static structural simulations were conducted in ANSYS Workbench 2022 R1 by systematically modifying localized geometric parameters, namely fillet radius and bracket thickness, at identified critical stress concentration regions. Two materials, A36 steel and GGG 60 ductile cast iron, were evaluated to investigate their influence on von Mises stress, total deformation, and safety factor under combined gravitational and retarder torque loading conditions. Three optimized configurations were compared with the initial design using an industry-oriented safety factor criterion (FS ≥ 2). The results demonstrate that localized geometric optimization significantly improves stress distribution and reduces deformation without excessive material addition. The optimal design, characterized by a 15 mm fillet radius and a thickness of 16 mm, achieved the highest safety factor while maintaining acceptable deformation levels. The proposed approach provides a practical and implementable design reference for improving retarder bracket performance in heavy-duty vehicle applications.