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The SAE Recommended Practice for measuring impulse noise from airbags, SAE J247, “Instrumentation for Measuring Acoustic Impulses within Vehicles”, was first published in 1971 and last affirmed in 1987. Many advances have occurred in understanding and technology since that time. Work in the automotive industry to investigate the characteristics of noise from airbag deployments has shown that large components of low frequency noise can be present when an airbag deploys in a closed vehicle. Others have shown that this low frequency noise can have a protective effect on the ear. Likewise, work for many years at the US Army Research Lab has investigated the risk of hearing loss for a human subjected to an acoustic impulse. That research led to the creation and validation of a mathematical model of the human ear, called Auditory Hazard Assessment Algorithm - Human (AHAAH).

Computational analysis of occupant safety has become an efficient tool to reduce the development time for a new product. Multi-body computer models (e.g. Madymo models) that simulate vehicle interior, restraint system and occupants in various crash modes have been widely used in the occupant safety area. To ensure public safety, many injury numbers, such as head injury criteria, chest acceleration, chest deflection, femur loads, neck load, and neck moment, are monitored. Deterministic optimization methods have been employed to meet various safety requirements. However, with the further emphasis on product quality and consistency of product performance, variations in modeling, simulation, and manufacturing, need to be considered.

Vehicle motion prior to a rollover can influence an occupant's position in the vehicle. Lateral deceleration prior to a tripped rollover may cause the occupant to move outboard. This outboard motion may have several effects on the occupant such as, repositioning the occupant with relation to the seat and seat restraint, and allowing the occupant's head to travel further into the side curtain deployment zone. To reduce occupant lateral motion, the effectiveness of applying tension to the seatbelt was evaluated. The evaluation consisted of two test conditions simulating vehicle lateral motion prior to a trip using a Deceleration Rollover Sled [1]. The test conditions were designed to ensure a vehicle experiences a period of pure lateral motion before the onset of a lateral trip. A standard seat belt combined with various means of applying tension and activated at different times during the test were evaluated.

This paper reviews the structural assessment of a compact vehicle under frontal impact according to Federal Motor Vehicle Safety Standard (FMVSS) 204 Requirement – Steering Control Reward Displacement. The steering column intrusion analysis is made adding a collapsible joint under axial load. Injury analysis is assessed for the driver according to Federal Motor Vehicle Safety Standard 208 Requirement – Occupant Crash Protection – considering HIC (Head Injury Criterion), Chest Deceleration, Chest Deflection and Femur Load. Computational models have been built based on Ford Motor Company experience using MECALOG RADIOSS (FEA Code) and TNO - MADYMO (Occupant Code).

Vehicle pitch and drop play an important role for occupant neck and head injury at frontal impact. The excessive vehicle header drop, due to vehicle pitch and drop during crash, induces aggressive interaction between occupant head and sun visor/header that causes serious head and neck injuries. For most of body-on-frame vehicles, vehicle pitch and drop have commonly been observed at frontal impact tests. It is because the vehicle body is pulled downward by frame rails, which bend down during crash. Hence, the challenges of frame design are not only to absorb crash energy but also to manage frame deformation for minimizing vehicle pitch and drop. In this paper, the finite element method is used to analyze frame deformation at full frontal impact. To ensure the quality of CAE model, a full vehicle FEA model is correlated to barrier tests. In addition, a study of CAE modeling affecting vehicle header drop is performed.

Vehicle to vehicle crash compatibility is becoming an increasingly more important consideration during vehicle safety development due to the increasing numbers of SUVs and pickups in the vehicle fleet. According to the Insurance Institute for Highway Safety (IIHS), their side impact crash test represents what happens when a passenger vehicle is struck by a pickup truck or SUV. The IIHS side impact test measures 37 different response criteria using an instrumented 5th percentile female SID-IIs ATD (anthropomorphic test device) in driver and left rear passenger seats. These measures are grouped into head and neck, torso, and pelvis and left leg regions. This paper will describe the development of transfer function equation models to assess the performance of design countermeasures by comparing the response measures of the torso region of the body.

The head, chest and femurs of three Hybrid II dummies were impacted with a ballistic pendulum at various angles to determine what differences in accelerometer and femur load cell output would result for a constant energy input. Also evaluated were suspicious tension loads in the femur load cell output when the legs were subjected to obvious off-center impacts during crash tests. It was found that the dummy legs can be subjected to very high torsion and bending loads which can have a significant effect on the femur load cell axial load outputs.

An automatic, falling, occupant-protecting net is being developed for spreading in front of automobile occupants in the time interval between vehicle impact and occupant collision. The device is designed to counteract forward body acceleration and minimize head, neck, and chest injuries. This device was investigated by sled and barrier tests using anthropomorphic dummies. Significant improvements in occupant kinematics and remarkable reduction in head and chest impact force has been observed. Some problems such as whiplash injury await solution but continuing investigation of proposed measures of correction show that they are not insurmountable.

This paper describes a newly developed microcomputer-based drowsiness warning system, which detects changes in the driver's alertness through his steering behavior. In developing this system, we first quantified several levels of alertness based on such physiological factors as brain activity and blinking. Tests were then conducted in which drivers fell into different degrees of drowsiness. Using the quantified alertness levels, we defined the “drowsy driver” and found unique steering patterns that could not be seen in normal driving. These patterns were entered into the memory unit of the microcomputer. When the sensor built into the steering wheel detects a drowsy steering pattern, the microcomputer recognizes the driver's drowsiness and activates a buzzer to warn the driver. In this paper, the process of determining the alertness levels is explained, along with the steering characteristics of the drowsy driver.

By nature, the driver's seat should be designed for work, while the passenger's seat should be built for comfort. This means that the functions of the seats are inherently different. Although many studies have been done on the driver's seat, the design and use of the passenger's seat have received little attention. This study examined a comfortable sitting posture in the passenger's seat. The results obtained have led to the development of two new devices. One device makes it possible for the seat cushion to move upward and forward as the seat tilts backward. The other device allows the upper portion of the seat back to tilt forward from the top of the lower seat back. These devices thus function to provide a comfortable sitting posture. This paper describes the new devices and presents the results of an investigation into a comfortable sitting posture for the occupant of the front passenger's seat.

Driver oblique far-side sled impacts were simulated with three surrogates. The EuroSID side impact dummy with rib extension (ES2re), the WorldSID side impact 50th percentile male dummy (WS50M), and the Global Human Body Modeling Consortium’s 50th percentile male human body (GHBM) models. The versions of the surrogates’ models were 7.0, 7.5.1, and 5.0, respectively. Surrogates were seated in the front left driver seat in a virtual generic crossover sled environment. The Finite Element (FE) based environment consisted of a driver seat, a center console, and a passenger seat. Two restraint systems were considered for each surrogate: belt only (BO) and belt plus a generic seat-mounted far-side impact airbag (BB). Surrogates were restrained using a 3-point belt that has a digressive shoulder force load limiter, and retractor, and anchor pretensioners. The far-side airbag used was a 37-liter in volume and has two chambers.

Finite element models of human body segments have been developed in recent years. Numerical simulation could be helpful when understanding injury mechanisms and to make injury assessments. In the lower leg injury research in NISSAN, a finite element model of the human ankle/foot is under development. The mesh for the bony part was taken from the original model developed by Beaugonin et al., but was revised by adding soft tissue to reproduce realistic responses. Damping effect in a high speed contact was taken into account by modeling skin and fat in the sole of the foot. The plantar aponeurosis tendon was modeled by nonlinear bar elements connecting the phalanges to the calcaneus. The rigid body connection, which was defined at the toe in the original model for simplicity, was removed and the transverse ligaments were added instead in order to bind the metatarsals and the phalanges. These tendons and ligaments were expected to reproduce a realistic response in compression.

In a joint effort between Ford Motor Company, Visteon Automotive Systems, Textron Automotive Company, and Dow Automotive the 1999 Mercury Cougar instrument panel (IP) was designed and engineered to reduce the weight and overall cost of the IP system. The original IP architecture changed from a traditional design that relied heavily upon the steel structure to absorb and dissipate unbelted occupant energy during frontal collisions to a hybrid design that utilizes both plastic and steel to manage energy. This design approach further reduced IP system weight by 1.88 Kg and yielded significant system cost savings. The hybrid instrument panel architecture in the Cougar utilizes a steel cross car beam coupled to steel energy absorbing brackets and a ductile thermoplastic substrate. The glove box assembly and the driver knee bolster are double shell injection molded structures that incorporate molded-in ribs for added stiffness.

Generally, exterior handles are one of the first parts that the user has physical interaction in the vehicle. A robust handle concept gives the user the idea of trust and good quality vehicle as first impression. Exterior handles, in which the concept is a handle body operated by applying a horizontal pull force, always pivoted in the front end and sliding against a reinforcement rail at rear end, are called strap handles. The kinetics seems to be simple, nevertheless special attention must be given regarding the interaction materials used in this system. Various plastic materials used in this system are subjected to water absorption at molecular level, changing their internal structure, resulting in swell and consequently a volume increase. This phenomenon that modifies the dimensions is known as hygroscopic expansion. In one hand, handles must present reduced wobble and free play.

An understanding of stiffness characteristics of different body regions, such as thorax, abdomen and pelvis of ES-2re and SID-IIs dummies under controlled laboratory test conditions is essential for development of both compatible performance targets for countermeasures and occupant protection strategies to meet the recently updated FMVSS214, LINCAP and IIHS Dynamic Side Impact Test requirements. The primary purpose of this study is to determine the transfer functions between the ES-2re and SID-IIs dummies for different body regions under identical test conditions using flat rigid wall sled tests. The experimental set-up consists of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and femur/knee impacting a stationary dummy seated on a rigid low friction seat at a pre-determined velocity.

The main purpose of this study was to determine the impact responses of the different body regions (shoulder, thorax, abdomen and pelvis/leg) of the ES-2re and SID-IIs dummies using rigid wall impacts under different initial test conditions. The experimental set-up consisted of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and knee impacting a stationary dummy seated on a rigid seat at a pre-determined velocity. The relative location and orientation of the load-wall plates was adjusted relative to the body regions of the ES-2re and SID-IIs dummies respectively.

The main purpose of this study was to determine the impact responses of the different body regions (shoulder, thorax, abdomen and pelvis/leg) of the ES-2re and SID-IIs dummies using rigid wall impacts under different initial test conditions. The experimental set-up consisted of a flat rigid wall with five instrumented load-wall plates aligned with dummy’s shoulder, thorax, abdomen, pelvis and knee impacting a stationary dummy seated on a rigid seat at a pre-determined velocity. The relative location and orientation of the load-wall plates was adjusted relative to the body regions of the ES-2re and SID-IIs dummies respectively.

Crash safety is a complex engineering field wherein a good understanding of energy attenuation capabilities due to an impact of various components and between different/adjacent components in the context of the vehicle environment is imperative. During a frontal impact of the vehicle, an occupant’s lower extremity tends to move forward and could impact one or more components of the instrument panel assembly. A glove box component design may have an influence on occupant’s lower extremity injuries when exposed to the occupant’s knees during a frontal impact. The objective of the present numerical study was to develop a novel glove box design with energy absorbing ribs and then comparing the results with the glove box with a knee airbag (KAB) design to help reduce anthropomorphic test device (ATD) lower leg responses.

The work presented here is part of the research done in the field of voice biometrics. This paper helps to understand the state-of-the-art in speaker recognition technology potentially capable of solving challenges related to speaker identification (to identify a speaker among multiple speakers) and speaker verification/authentication (to recognize the current speaking person at a pre-defined access level and authenticate accordingly). The research was focused on performing an unbiased evaluation of two individual voice biometric services. The level of accuracy in identifying and authenticating individuals using these services provides an insight into the current state of technology and the state of what other dual authentication methods could be used to achieve a desired True Acceptance Rate (TAR) and False Acceptance Rates (FAR).

Interest in rear-seat occupant safety has increased in recent years. Information relevant to rear-seat occupant interior space and kinematics are needed to evaluate injury risks in real-world accidents. This study was conducted to first assess the effect of size and restraint conditions, including belt misuse, on second-row occupant kinematics and to then document key clearance measurements for an Anthropomorphic Test Device (ATD) seated in the second row in modern vehicles from model years 2015-2020. Twenty-two tests were performed with non-instrumented ATDs; three with a 5th percentile female Hybrid III, 10 tests with a 10-year-old Hybrid III, and 9 tests with a 6-year-old Hybrid III. Test conditions included two sled bucks (mid-size car and sport utility vehicle (SUV)), two test speeds (56 and 64 km/h), and various restraint configurations (properly restrained and improperly restrained configurations). Head and knee trajectories were assessed.