关键词: 后轮毂支架；多目标优化；折衷规划法；拓扑优化；轻量化

Abstract: To address the engineering challenge of balancing multiple conflicting performance objectives with lightweight requirements in the design of automotive rear hub brackets, this paper proposes a multi-objective topology optimization method based on the compromise programming approach. A maximum design space model is constructed based on suspension hardpoints, and a multi-objective optimization model is formulated with volume fraction and critical hardpoint stiffness as constraints, aiming to simultaneously minimize structural compliance and maximize the first natural frequency. Unlike conventional weighted sum methods, the compromise programming approach effectively resolves the non-convex conflicts between stiffness under multiple load cases and natural frequency by seeking a compromise solution with the shortest distance to the ideal point, thereby enabling rational material distribution. The optimization is performed using OptiStruct, followed by structural reconstruction and iterative design in Siemens NX. The validation results show that the optimized bracket exhibits superior stiffness at all hardpoints compared to the benchmark model, with a maximum stress of 201 MPa under extreme conditions, satisfying strength requirements. The mass is reduced from 5.27 kg to 3.15 kg, achieving a 40.2% weight reduction. The proposed method provides a transferable engineering pathway for the synergistic design of high performance and lightweight in critical chassis components.

Key words: rear hub bracket; multi-objective optimization; compromise programming approach; topology optimization; lightweight