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The significance and the number of vehicle safety features enabled via connectivity continue to increase. OnStar, with its automatic airbag notification, was one of the first vehicle safety features that demonstrate the enhanced safety benefits of connectivity. Vehicle connectivity benefits have grown to include remote software updates, data analytics to aid with preventative maintenance and even to theft prevention and recovery. All of these services require available and reliable connectivity. However, except for the airbag notification, none have strict latency requirements. For example, software updates can generally be postponed till reliable connectivity is available. Data required for prognostic use cases can be stored and transmitted at a later time. A new set of use cases are emerging that do demand continuous, reliable and low latency connectivity. For example, remote control of autonomous vehicles may be required in unique situations.

Studies show that the pedestrian population at high risk of injury consists of both young children and adults. The goal of this study is to gain understanding in the mechanisms that lead to injuries for children and adults. Multi-body pedestrian human models of two specific anthropometries, a 6year-old child and a 50th percentile adult male, are applied. A vehicle model is developed that consists of a detailed rigid finite element mesh, validated stiffness regions, stiff structures underlying the hood and a suspension model. Simulations are performed in a test matrix where anthropometry, impact speed and impact location are variables. Bumper impact occurs with the tibia of the 50th percentile adult male and with the thigh of the 6-year-old child. The head of a 50th percentile male impacts the lower windshield, while the 6-year-old child's head impacts the front part of the hood.

A recent study of U.S. crash data has shown that children 0-23 months of age in forward-facing child restraint systems (FFCRS) are 76% more likely to be seriously injured in comparison to children in rear-facing child restraint systems (RFCRS). Motivated by the epidemiological data, seven sled tests of dummies in child seats were performed at the University of Virginia using a crash pulse similar to FMVSS 213 test conditions. The tests showed an advantage for RFCRS; however, real-world crashes include a great deal of variability among factors that may affect the relative performance of FFCRS and RFCRS. Therefore, this research developed MADYMO computational models of these tests and varied several real-world parameters. These models used ellipsoid models of Q-series child dummies and facet surface models of American- and Swedish- style convertible child restraints (CRS).

It has been reported that lower extremity injuries represent a measurable portion of all moderate-to-severe automobile crash- related injuries. Thus, a simple tool to assist with the design of leg and foot injury countermeasures is desirable. The objective of this study is to develop a mathematical model which can predict load propagation and kinematics of the foot and leg in frontal automotive impacts. A multi-body model developed at the University of Virginia and validated for blunt impact to the whole foot has been used as basis for the current work. This model includes representations of the tibia, fibula, talus, hindfoot, midfoot and forefoot bones. Additionally, the model provides a means for tensioning the Achilles tendon. In the current study, the simulations conducted correspond to tests performed by the Transport Research Laboratory and the University of Nottingham on knee-amputated cadaver specimens.

Rupture of the thoracic aorta is a leading cause of rapid fatality in automobile crashes, but the mechanism of this injury remains unknown. One commonly postulated mechanism is a differential motion of the aortic arch relative to the heart and its neighboring vessels caused by high-magnitude acceleration of the thorax. Recent Indy car crash data show, however, that humans can withstand accelerations exceeding 100 g with no injury to the thoracic vasculature. This paper presents a method to investigate the efficacy of acceleration as an aortic injury mechanism using high-acceleration, low chest deflection sled tests. The repeatability and predictability of the test method was evaluated using two Hybrid III tests and two tests with cadaver subjects. The cadaver tests resulted in sustained mid-spine accelerations of up to 80 g for 20 ms with peak mid-spine accelerations of up to 175 g, and maximum chest deflections lower than 11% of the total chest depth.

This paper presents a technique for developing corridors from individual subject responses contained in experimental biomechanical data sets. Force-deflection response is used as an illustrative example. The technique begins with a method for averaging human subject force-deflection responses in which curve shape characteristics are maintained and discontinuities are avoided. Individual responses sharing a common characteristic shape are averaged based upon normalized deflection values. The normalized average response is then scaled to represent the given data set using the mean peak deflection value associated with the set of experimental data. Finally, a procedure for developing a corridor around the scaled normalized average response is presented using standard deviation calculations for both force and deflection.

This paper examines an originally designed airbag deployment system for use in static experimental testing. It consists of a pressure vessel and valve arrangement with pneumatic and electric controls. A piston functions like a valve when operated and is activated pneumatically to release the air in the tank. Once released, the air fills the attached airbag. The leading edge velocity can be controlled by the initial pressure in the tank, which can range up to 960 kPa. Three different test configurations were studied, which resulted in leading edge deployment speeds of approximately 20 m/s, 40 m/s, and 60 m/s. In experiments using this system, seven types of airbags were tested that differed in their material, coating, and presence of a tether. Data for each series of tests is provided. High speed video and film were used to record the deployments, and a pressure transducer measured the airbag's internal pressure.

This paper presents the development of a sensor suite that is used to measure the toeboard threedimensional (3D) dynamic deformation during a crash test, along with the methodology to use the sensor suite for toeboard measurement. The sensor suite consists of three high-speed cameras, which are firmly connected through a rigid metal frame. Two cameras, facing directly towards the toeboard, measure the shape of the toeboard through stereovision. The third camera, facing the ground, is equipped with a three-axis gyroscope and a three-axis accelerometer and localizes the sensor suite globally for removing the vibration of the sensor suite. The sensor suite was mounted onto the car through car seat mounting bolt holes, and a hole was made on the floor to let the downward camera see the ground. A pipeline using the data collected by the sensor suite is also introduced in this paper.

The THOR-NT dummy has been developed and continuously improved by NHTSA to provide automotive manufacturers an advanced tool that can be used to assess the injury risk of vehicle occupants in crash tests. With the recent improvements of finite element (FE) technology and the increase of computational power, a validated FE model of THOR may provide an efficient tool for the design optimization of vehicles and their restraint systems. The main goal of this study was to improve biofidelity of a head-neck FE model of THOR-NT dummy. A three-dimensional FE model of the head and neck was developed in LS-Dyna based on the drawings of the THOR dummy. The material properties of deformable parts and the joints properties between rigid parts were assigned initially based on data found in the literature, and then calibrated using optimization techniques.

This paper studies the effect of different longitudinal load conditions, roundabout cross-sectional geometry, and different semi-truck pneumatic suspension systems on roll stability in roundabouts, which have become more and more popular in urban settings. Roundabouts are commonly designed in their size and form to accommodate articulated heavy vehicles (AHVs) by evaluating such affects as off-tracking. However, the effect of the roadway geometry in roundabouts on the roll dynamics of semi-tractors and trailers are equally important, along with their entry and exit configuration. , Because the effect of the roundabout on the dynamics of trucks is further removed from the immediate issues considered by roadway planner, at times they are not given as much consideration as other roadway design factors.

Kia and Hyundai released publicly available tools in the spring of 2013 to read model year (MY) 2013 vehicle event data recorders (EDRs). By empirical testing, this study determined the tools also read data from some 2010-2012 models as EDRs were phased in by the manufacturer. Fifty-four (54) MY 2010-2012 airbag control module EDRs from the National Highway Traffic Safety Administration's (NHTSA) New Car Assessment Program (NCAP) crash tests were downloaded direct-to-module. The vehicles analyzed were exposed to frontal, side moving deformable barrier (MDB), and side pole tests. The EDR data was compared to the reference instrumentation for speed and Delta V data. Other data elements were also tabulated but are not evaluated for accuracy because they were not fully exercised during the crash tests, the reference instrumentation was not available, or they were outside the scope of this paper.

Active safety systems have become an essential part of today's vehicles including SUVs and LTVs. Although they have advanced in many aspects, there are still many areas that they can be improved. Especially being able to obtain information about tire-vehicle states (e.g. tire slip-ratio, tire slip-angle, tire forces, tire-road friction coefficient), would be significant due to the key role tires play in providing directional stability and control. This paper first presents the implementation strategy for a dynamic tire slip-angle estimation methodology using a combination of a tire based sensor and an observer system. The observer utilizes two schemes, first of which employs a Sliding Mode Observer to obtain lateral and longitudinal tire forces. The second step then utilizes the force information and outputs the tire slip-angle using a Luenberger observer and linearized tire model equations.

Event data recorders (EDRs) must survive regulatory frontal and side compliance crash tests if installed within a car or light truck built on or after September 1, 2012. Although previous research has shown that EDR data are surviving these tests, little is known about whether EDRs are capable of surviving collisions of higher delta-v, or crashes involving vehicle fire or immersion. The goal of this study was to determine the survivability of light vehicle EDRs in real world fire, immersion, and high change in velocity (delta-v) cases. The specific objective was to identify the frequency of these extreme events and to determine the EDR data download outcome when subject to damage caused by these events. This study was performed using three crash databases: the Fatality Analysis Reporting System (FARS), the National Automotive Sampling System / Crashworthiness Data System (NASS/CDS), and the National Motor Vehicle Crash Causation Survey (NMVCCS).

Multiple laboratory dynamic test methods have been developed to evaluate vehicle crashworthiness in rollover crashes. However, dynamic test methods remove some of the characteristics of actual crashes in order to control testing variables. These simplifications to the test make it difficult to compare laboratory tests to crashes. One dynamic method for evaluating vehicle rollover crashworthiness is the Dynamic Rollover Test System (DRoTS), which simulates translational motion with a moving road surface and constrains the vehicle roll axis to a fixed plane within the laboratory. In this study, five DRoTS vehicle tests were performed and compared to a pair of unconstrained steering-induced rollover tests. The kinematic state of the unconstrained vehicles at the initiation of vehicle-to-ground contact was determined using instrumentation and touchdown parameters were matched in the DRoTS tests.

Computer simulations, dummy experiments with a new enhanced upper extremity, and small female cadaver experiments were used to analyze the small female upper extremity response under side air bag loading. After establishing the initial position, three tests were performed with the 5th percentile female hybrid III dummy, and six experiments with small female cadaver subjects. A new 5th percentile female enhanced upper extremity was developed for the dummy experiments that included a two-axis wrist load cell in addition to the existing six-axis load cells in both the forearm and humerus. Forearm pronation was also included in the new dummy upper extremity to increase the biofidelity of the interaction with the handgrip. Instrumentation for both the cadaver and dummy tests included accelerometers and magnetohydrodynamic angular rate sensors on the forearm, humerus, upper and lower spine.

Since 1966 the federal government, through the National Highway Traffic Safety Administration, has promulgated regulations governing the crash safety of motor vehicles, with particular attention to passenger cars. However, during the next four years, most of the regulations will also apply to light trucks and vans. There are now 53 Federal Motor Vehicle Safety Standards (FMVSS). These standards primarily regulate the safety of new vehicles. For many disabled persons, especially those confined to wheelchairs, vehicles must be extensively modified to allow them to drive, or to ride as passengers. The objective of this paper is to examine the safety level intended to be afforded to able bodied persons by the crashworthiness FMVSS and to make observations on the special requirements of modified vehicles to afford the same level of safety to disabled persons. We will emphasize the safety needs of those who use vans since vans are the vehicles most extensively modified.

Heavy-vehicle event data recorders (HVEDRs) provide a source of temporal vehicle data just prior to, during, and for a short period after, an event. In the 1990s, heavy-vehicle (HV) engine manufacturers expanded the capabilities of engine control units (ECU) and engine control modules (ECM) to include the ability to record and store small amounts of parametric vehicle data. This advanced capability has had a significant impact on vehicle safety by helping law enforcement, engineers, and researchers reconstruct events of a vehicle crash and understand the details surrounding that vehicle crash. Today, EDR technologies have been incorporated into a wide range of heavy vehicle (HV) safety systems (e.g., crash mitigation systems, air bag control systems, and behavioral monitoring systems). However, the adoption of EDR technologies has not been uniform across all classes of HVs or their associated vehicle systems.

Females have higher frequency and risk of foot and ankle injuries in motor vehicle collisions than similar-sized males. Therefore, lower extremity biofidelity and accurate injury prediction of female ATDs is critical. This paper aims to compare the THOR 5th percentile female (THOR-05F) anthropomorphic test device (ATD) response with male and female PMHS data of various sizes under ankle inversion and eversion. The THOR-05F lower extremity was subjected to dynamic inversion and eversion ankle loading with a constant 2000N axial force applied through the tibia. Twelve THOR-05F tests (3 inversion and 3 eversion on both, left and right legs) were performed with boundary conditions consistent with previous post-mortem human subject (PMHS) lower extremity tests.

The anatomical dimensions, inertial properties, and mechanical responses of cadaver leg, foot, and ankle specimens were evaluated relative to those of human volunteers and current anthropometric test devices. Dummy designs tested included the Hybrid III, Hybrid III with soft joint stops, ALEX I, and the GM/FTSS lower limbs. Static and dynamic tests of the leg, foot, and ankle were conducted at the laboratories of the Renault Biomedical Research Department and the University of Virginia. The inertial and geometric properties of the dummy lower limbs were measured and compared with cadaver properties and published volunteer values. Compression tests of the leg were performed using static and dynamic loading to determine compliance of the foot and ankle. Quasi-static rotational properties for dorsiflexion and inversion/eversion motion were obtained for the dummy, cadaver, and volunteer joints of the hindfoot.

In order to evaluate a human surrogate, the human and surrogate response must be defined. The purpose of this study was to evaluate the response of cadaver subjects to blunt impacts to the frontal bone, nasal bone and maxilla. Force-displacement corridors were developed based on the impact response of each region. Variation in the force-displacement response of the cadaver subjects due to the occurrence of fracture and fracture severity was demonstrated. Additionally, impacts were performed at matched locations using the Facial and Ocular CountermeasUre Safety (FOCUS) headform. The FOCUS headform is capable of measuring forces imposed onto facial structures using internal load cells. Based on the tests performed in this study, the nasal region of the FOCUS headform was found to be the most sensitive to impact location. Due to a wide range in geometrical characteristics, the nasal impact response varied significantly, resulting in wide corridors for human response.