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Characterization of the plastic and ductile fracture behavior of a ferrous casting commonly used for the steering knuckle of an automotive suspension system is presented in this work. Ductile fracture testing for various coupon geometries was conducted to simulate a wide range of stress states. Failure data for the higher stress triaxiality were obtained from tension tests conducted on thin flat specimens, wide flat specimens and axisymmetric specimens with varying notch radii. The data for the lower triaxiality were generated from thin-walled tube specimens subjected to torsional loading and compression tests on cylindrical specimens. The failure envelopes for the material were developed utilizing the test data and finite element (FE) simulations of the corresponding test specimens. Experiments provided the load-displacement response and the location of fracture initiation.

A resin fuel lid capable of being electrostatically painted on-line with the vehicle body-in-white was developed to achieve a light weight fuel adapter assembly with improved color match to surrounding body panels when compared with outsourced painting. The fuel lid was molded out of a conductive, high heat capable PA/PPO resin, and painted with automotive body paint systems. Key development items for this part included validation of part conductivity, on-line capability of the resin material, development of an attachment scheme to achieve proper grounding of the part, determination of paint jig location for proper paint coverage and color match to the body, and evaluation of the final fit & finish. These studies were conducted in combination of both lab and on-line trials. Additionally, the final painted part assembly was extensively tested to achieve the appropriate quality of the surface treatment and strength and durability of the design construction.

Pediatric pedestrians are frequently involved in Pedestrian versus Motor Vehicle Collisions (PMVCs). While in recent years, the automotive industry has worked towards making cars less aggressive to pedestrians, the efforts have mainly focused on adult pedestrian safety. When they have included considerations for children, only head injuries have been evaluated. The development of automotive counter-measures that provide protection for both adult and pediatric pedestrians requires access to injury criteria for the entire body that specifically account for both the age-dependent tissue properties and the pedestrian's size. The objective of the present study is to derive lateral injury criteria for the head, neck, thorax, abdomen and pelvis that can be used in finite element and multi-body simulations of PMVCs involving the 6-year-old pedestrian (corresponding injury criteria for the upper and lower extremities are derived in part II of this study).

This research investigates the variation of pedestrian stance in pedestrian-automobile impact using a validated multi-body vehicle and human model. Detailed vehicle models of a small family car and a sport utility vehicle (SUV) are developed and validated for impact with a 50th percentile human male anthropometric ellipsoid model, and different pedestrian stances (struck limb forward, feet together, and struck limb backward) are investigated. The models calculate the physical trajectory of the multi-body models including head and torso accelerations, as well as pelvic force loads. This study shows that lower limb orientation during a pedestrian-automobile impact plays a dominant role in upper body kinematics of the pedestrian. Specifically, stance has a substantial effect on the subsequent impacts of the head and thorax with the vehicle. The variation in stance can change the severity of an injury incurred during an impact by changing the impact region.

Pediatric pedestrians are frequently involved in Pedestrian versus Motor Vehicle Collisions (PMVCs). While in recent years, the automotive industry has worked towards making cars less aggressive to pedestrians, the efforts have mainly focused on adult pedestrian safety. When they have included considerations for children, only head injuries have been evaluated. The development of automotive countermeasures that provide protection for both adult and pediatric pedestrians requires access to injury criteria for the entire body that specifically account for both the age-dependent tissue properties and the pedestrian's size. The objective of the present study is to derive lateral injury criteria for the upper and lower extremities that can be used in finite element and multi-body simulations of PMVCs involving the 6-year-old pedestrian (corresponding injury criteria for the head, neck, thorax, abdomen and pelvis are derived in part I of this study).

The Thor-Lx leg and foot complex is being developed by the National Highway Traffic Safety Administration (NHTSA), the Applied Safety Technologies Corporation, and GESAC, Inc., as a new research and development (R&D) tool which will be more biofidelic than the current Hybrid-III lower extremity. This paper reviews the results from a matrix of tests performed to evaluate the response of the Thor-Lx in comparison to the Hybrid-III lower extremity in high-speed frontal crashes. The testing included three 64 km/h frontal offset deformable barrier tests and two 56 km/h flat rigid barrier tests. Testing was done using the following Anthropomorphic Test Device (ATD) combinations: Hybrid-III with the Hybrid-III Enhanced Instrumented Tibia, Hybrid-III with the Thor-Lx, and Thor with the Thor-Lx. The response of the lower extremity was found to vary with each leg and torso combination.

The desire to increase production and reduce cost while increasing environmental consciousness, is a constant challenge in the thermoplastic olefin (TPO) paint industry. Typically, TPO substrates are painted with an adhesion promoter for durability, and top coats for appearance. Although the adhesion promoter has an important function, the intrinsic value is not significant compared to top coats. A process and material was developed to eliminate conventional adhesion promoter spray application. By incorporating a novel adhesion promoter into the aqueous pretreatment system, many of the stresses of high production volumes, and operating costs were addressed while improving environmental awareness.

Measuring the real-world performance of emission control technologies is an important aspect in the development of advanced low-emission vehicles. In addition, data acquired from such measurements can be used to improve the accuracy of air quality predictive models. Honda has developed an on-board sampling/analysis system capable of measuring on-road emissions at ULEV levels and below. Ambient air can be analyzed simultaneously. This FTIR-based system can measure several species; this paper will focus on NMHC, NOX, and CO. Techniques were developed to address the challenges associated with acquiring accurate real-time data at concentrations below 1 ppm in an on-road vehicle. Validation studies performed with reference gases and vehicle exhaust indicate a very good correlation between the on-road analyzer system and classic bench methods for all target compounds. Dynamic studies performed by the University of California, Riverside, also show good correlation.

A series of eight sled tests was conducted using Hybrid III dummies and cadavers in order to examine the influence of foot placement on the brake pedal in frontal collisions. The brake pedal in the sled runs was fixed in a fully depressed position and the occupants' muscles were not tensed. The cadaver limbs and the Hybrid III lower extremities with 45° ankle and soft joint-stop were extensively instrumented to determine response during the crash event. Brake pedal reaction forces were measured using a six-axis load cell and high speed film was used for kinematic analysis of the crashes. Four right foot positions were identified from previous simulation studies as those orientations most likely to induce injury. In each test, the left foot was positioned on a simulated footrest, acting as a control variable that produced repeatable results in all dummy tests. Each of the different right foot orientations resulted in different loads and motions of the right leg and foot.

An Articulated Total Body frontal crash simulation was created with the dummy's right foot placed on the brake pedal. This study examined how interaction of the driver's foot with the brake pedal influenced the behavior of the lower extremities in frontal collisions. Braking parameters considered in the study included foot position on the pedal, whether or not the occupant's muscles were tensed and if the brake pedal was rigid or was allowed to depress. Two basic foot positions were identified as most likely to induce injury of the lower limb. One represented a foot that was pivoted about the heel from the gas pedal to the brake pedal. The other position replicated a foot that was lifted from the gas pedal to the brake pedal, resulting in an initial gap between the heel and floor. Both positions resulted in different loads and behavior of the foot, indicating that driver pre-impact position is a contributing factor to one's injury risk.