Access Type

Open Access Dissertation

Date of Award

January 2020

Degree Type

Dissertation

Degree Name

Ph.D.

Department

Civil and Environmental Engineering

First Advisor

King H. Yang

Second Advisor

Hwai C. Wu

Abstract

The objective of this study was to augment the knowledge of the far-side occupant injury biomechanics in side impact vehicle crashes. Most research studies conducted to investigate the far-side occupant injuries are through the field crash data for a better understanding of human impact responses, injury mechanisms, and injury tolerance levels. The data obtained from field data is also used in the development of injury mitigation technologies, such as safety belts, airbags, etc. A field data represents the injury outcome of an automotive crash, but it doesn’t leave behind enough information for in-depth knowledge. The use of cadaver is the next best approach.

The third and popular approach is the use of crash testing dummies (ATD). Crash dummies are the mechanical human-like machine to mimic body responses during impact. Due to structural simplifications in representing human anatomy in crash testing dummies, the predictive capabilities of ATD dummies for injuries are limited. Based on the literature review, the far-side impact could produce injuries like frontal, side, and rear impact; however, there is currently no single dummy available to capture injuries from these crash modes without any modifications.

Recently, advancements in computer processing-speed and available large size memory have made it possible to simulate a large and complicated finite element model at a reasonably quick turnaround time. This capability drove the engineers to develop a computer-based human body model for the research work. The human body model represents a real human that is free from any crash mode dependency. Therefore, the finite element human body model (50th Percentile male GHBM) was the best choice for the study. The study was conducted to investigate the far-side occupant responses in a complex but realistic environment utilizing a finite element full vehicle model of a U.S. based mid-size sedan. The first step was to correlate finite element vehicle responses with the NHTSA available tests. The next step was to check the predictability of the GHBM responses and compared them with data obtained from the corresponding cadaver responses. A rigid sled finite element model was developed based on the dimensions published in the literature using a 3-point belted human body model, which was placed and configured as the physical test. A decent correlation was found between the GHBM and cadaver responses.

A series of DOE simulations were conducted based on the side IIHS and LINCAP barriers with varying positions between the wheelbase and initial speed. Two occupant responses were investigated; in one scenario, one far-side occupant was seated on the first row while the second case, a near-side occupant, was placed with the far-side occupant. Several selected responses of the human body were processed for the far-side and near-side occupants using the Mode-Frontier tool. Currently, there is no far-side impact test protocol in the U.S. Therefore, a human body model was placed in the corresponding side IIHS and LINCAP test procedures and assessed the far-side and near-side occupant responses. A high-level test procedure was proposed to maximize the vehicle translational acceleration at the non-impact rocker B-pillar. Finally, a conceptual far-side airbag, 3-point/4-point seatbelt system, and optimized center console were evaluated on the far-side occupant to quantify the benefits of occupant head responses and rib deflection.

Download

Share

COinS