Hu Jingwen, Klinich Kathleen D, Manary Miriam A, Flannagan Carol A C, Narayanaswamy Prabha, Reed Matthew P, Andreen Margaret, Neal Mark, Lin Chin-Hsu
a University of Michigan Transportation Research Institute , Ann Arbor , Michigan.
b General Motors , Warren , Michigan.
Traffic Inj Prev. 2017 May 29;18(sup1):S85-S95. doi: 10.1080/15389588.2017.1298096. Epub 2017 Mar 15.
Federal regulations in the United States require vehicles to meet occupant performance requirements with unbelted test dummies. Removing the test requirements with unbelted occupants might encourage the deployment of seat belt interlocks and allow restraint optimization to focus on belted occupants. The objective of this study is to compare the performance of restraint systems optimized for belted-only occupants with those optimized for both belted and unbelted occupants using computer simulations and field crash data analyses.
In this study, 2 validated finite element (FE) vehicle/occupant models (a midsize sedan and a midsize SUV) were selected. Restraint design optimizations under standardized crash conditions (U.S.-NCAP and FMVSS 208) with and without unbelted requirements were conducted using Hybrid III (HIII) small female and midsize male anthropomorphic test devices (ATDs) in both vehicles on both driver and right front passenger positions. A total of 10 to 12 design parameters were varied in each optimization using a combination of response surface method (RSM) and genetic algorithm. To evaluate the field performance of restraints optimized with and without unbelted requirements, 55 frontal crash conditions covering a greater variety of crash types than those in the standardized crashes were selected. A total of 1,760 FE simulations were conducted for the field performance evaluation. Frontal crashes in the NASS-CDS database from 2002 to 2012 were used to develop injury risk curves and to provide the baseline performance of current restraint system and estimate the injury risk change by removing the unbelted requirement.
Unbelted requirements do not affect the optimal seat belt and airbag design parameters in 3 out of 4 vehicle/occupant position conditions, except for the SUV passenger side. Overall, compared to the optimal designs with unbelted requirements, optimal designs without unbelted requirements generated the same or lower total injury risks for belted occupants depending on statistical methods used for the analysis, but they could also increase the total injury risks for unbelted occupants.
This study demonstrated potential for reducing injury risks to belted occupants if the unbelted requirements are eliminated. Further investigations are necessary to confirm these findings.
美国联邦法规要求车辆在使用未系安全带的测试假人时满足乘员性能要求。取消对未系安全带乘员的测试要求可能会鼓励安全带联锁装置的部署，并使约束系统优化能够专注于系安全带的乘员。本研究的目的是通过计算机模拟和现场碰撞数据分析，比较仅针对系安全带乘员优化的约束系统与针对系安全带和未系安全带乘员均优化的约束系统的性能。
在本研究中，选择了2个经过验证的有限元（FE）车辆/乘员模型（一辆中型轿车和一辆中型SUV）。在标准化碰撞条件（美国国家汽车碰撞测试标准（U.S.-NCAP）和联邦机动车安全标准（FMVSS）208）下进行约束设计优化，在两辆车内的驾驶员和右前乘客位置使用混合III型（HIII）小型女性和中型男性人体模型测试装置（ATD），分别有无未系安全带的要求进行测试。在每次优化中，使用响应面法（RSM）和遗传算法的组合对总共10至12个设计参数进行变化。为了评估有无未系安全带要求下优化后的约束系统的现场性能，可以选择55种正面碰撞条件（涵盖比标准化碰撞更多样化的碰撞类型）进行研究。总共进行了1760次有限元模拟以进行现场性能评估。使用2002年至2012年国家汽车抽样系统 - 碰撞数据系统（NASS-CDS）数据库中的正面碰撞数据来绘制损伤风险曲线，并提供当前约束系统基线性能，并估计通过取消未系安全带要求后的损伤风险变化。
在4种车辆/乘员位置条件中的3种情况下，未系安全带要求不影响最佳安全带和安全气囊设计参数，除了SUV乘客侧。总体而言，与有未系安全带要求的最佳设计相比，无未系安全带要求的最佳设计根据用于分析的统计方法，对系安全带的乘员产生相同或更低的总损伤风险，但它们也可能增加未系安全带乘员的总损伤风险。
本研究表明，如果取消未系安全带要求，有可能降低系安全带乘员的损伤风险。需要进一步研究以证实这些发现。
