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Production variation analysis of vehicle NVH performance becomes more and more necessary in development process. In order to accurately evaluate vehicle NVH responses, this paper presents a general framework involving excitation evaluation, vehicle FE model and results post-processing. Through mind map and parameter diagram analysis of idling shake, the major cause was found to be piece to piece of its powertrain rubber mounts system. Along with the vehicle NVH simulation, a novel decoupled robust-based optimization strategy called SRBF-RBO is applied to PTMS robust optimization. SRBF-RBO distinguishingly features two-steps searching strategy, the “shifting” performance and “tightening” distribution. Based on the adaptive metamodeling technique of SRBF strategy, the “shifting” operation can quickly search deterministic optimum, and improves the approximation accuracy of metamodels around the optimum in local region.

Body structure design needs to meet multi-attributes requirements such as global bend stiffness/modal, torsion stiffness/modal, Noise and velocity transfer functions (NTF/VTF), and others. Computer-aided engineering (CAE) is a significant way to enhance the accuracy of design results. However, it also brings computation burden for optimization. In order to improve the performance and reduce the weight of automobile body structure, this paper presents a novel process of body CAE multi-attributes optimization. Four significant phases are described: 1) Sensitivity analysis for each body CAE performance, 2) MDO process, 3) Non-sensitive gauges reducing, and 4) Slightly optimization. Considering the mixed variables in the MDO process including continuous geometry shapes and discrete gauges, the developed continuous relaxation method was employed to deal with such situation.