越野功能車之抗碰撞能力分析

The Crashworthiness Analysis of Off-Road Utility Vehicle

呂瑋峻(Weijun Lu)

指導教授 ： 胡惠文

國立屏東科技大學/工學院/車輛工程系所/碩士(2009年)

摘要

本論文主要是利用電腦輔助工程分析(Computer-aided engineering, CAE)技術針對合作廠商所設計的越野功能車，進行整車之抗碰撞能力分析，包括：前碰撞、側碰撞及後碰撞。整車碰撞模型包含車體主結構與動力系統、懸吊系統、車體相關配件(包括：保險桿、水箱、油箱、座椅載物箱、引擎、前、後差速器、前、後懸吊系統、輪胎)及碰撞假人，車體主結構已經在先前的研究中完成模型驗證，懸吊系統經過本研究模型更新後確保機構運動行為等效於實體，假人模型則由LSTC(Livermore Software Technology Corp.)所提供。結構材料彈塑性模型是採用Cowper-Symonds Plasticity Model with Piecewise Linear，此模型可考慮應變率對於材料變形行為的影響，適用於金屬等向性材料的塑性變形分析，其中之應變率參數(C, p)是經由衝擊試驗比對驗證所獲得的數值。研究中分析軟體採用LS-PrePost，求解器則採用ANSYS LS-DYNA，探討整車空車(空車+正駕駛)重量，在前、後碰撞中以時速30英哩作為分析條件，而側碰撞則以時速19英哩作為分析條件。最後從碰撞後所產生之車體結構變形，以美國聯邦車輛安全標準(Federal Motor Vehicle Safety Standard, FMVSS)為碰撞標準，判斷乘客安全空間是否遭受侵入，及油箱是否因撞擊而破裂，並從假人在碰撞中之動作推測人體可能受到之傷害。

關鍵字

越野功能車 ； CAE ； 碰撞分析 ； 碰撞假人 ； 車輛碰撞 ； FMVSS

並列摘要

The objective of the research is to investigate the crashworthiness of a Off-Road Utility Vehicle (OUV) by using computer-aided engineering (CAE) technology. The finite element model of the full vehicle structure and crash test dummy has been developed by using the software LS-PrePost. The full vehicle model includes main body structure, bumper, seat, water tank, fuel tank, engine, transmission, container, suspensions, differential gears, tires, etc. The finite element model of main body structure had been validated by using experimental modal analysis (EMA). The finite element model of Hybrid III 50th Percentile crash test dummy is provided from Livermore Software Technology Corp (LSTC). Cowper-Symonds with Piecewise Linear Plasticity Model is used to simulate the dynamic behavior of structural materials. The strain-rate dependent parameters of this model are obtained from the bending impact tests of the body structures. The full model is then used to perform the front, side and rear impact analyses by using software ANSYS LS-DYNA and based on the FMVSS (Federal Motor Vehicle Safety Standard). The significant results provide the designer the guidance of reinforcement design of the body structure and the prediction of passage injuring risks.

並列關鍵字

Off-Road Utility Vehicle ； CAE ； Crashworthiness Analysis ； crash test dummy ； front impact ； side impact ； rear impact ； bending impact test ； plasticity model

參考文獻

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