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This paper intends to present a novel optimal trajectory planning method for obstacle avoidance on highways. Firstly, a mapping from the road Cartesian coordinate system to the road Frenet-based coordinate system is built, and the path lateral offset in the road Frenet-based coordinate system is represented by a function of quintic polynomial respecting the traveled distance along the road centerline. With different terminal conditions regarding its position, heading and curvature of the endpoint, and together with initial conditions of the starting point, the path planner generates a bunch of candidate paths via solving nonlinear equation sets numerically. A path selecting mechanism is further built which considers a normalized weighted sum of the path length, curvature, consistency with the previous path, as well as the road hazard risk.

Vehicle-to-Vehicle (V2V) safety application research based on short range real-time communication has been researched for over a decade. Examples of V2V applications include Electronic Emergency Brake Light, Do Not Pass Warning, Lane Departure Warning, and Intersection Movement Assist. It is hoped that these applications, whether present as warning or intervention, will help reduce the incidence of traffic collisions, fatalities, injuries, and property damage. The safety benefits of these applications will likely depend on many factors, such as usability, market penetration, driver acceptance, and reliability. Some applications, such as DNPW and IMA, require a longer communication range to be effective. In addition, Dedicated Short Range Communications (DSRC) may be required to communicate without direct line of sight. The signal needs to overcome shadowing effects of other vehicles and buildings that are in the way.

Optimization design for vehicle front-end structures has proven rather essential and been extensively used to improve the vehicle performance. Nevertheless, the front-end structure needs to meet the requirement of both pedestrian safety and structural stiffness which are somewhat contradicting to each other. Furthermore, an optimal design could become less meaningful or even unacceptable when some uncertainties present. In the paper, a multi-objective discrete robust optimization (MODRO) algorithm is used to minimize the injury of head and maximize the structural stiffness involving uncertainties. MODRO algorithm is achieved by coupling grey relational analysis (GRA) and principal component analysis (PCA) with Taguchi method. The optimized result shows that the MODRO algorithm improved performance of pedestrian head injury and robustness of the vehicle front-end structure.

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.

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).

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 traditional deterministic optimal design is mostly based on meeting regulatory requirements specified in impact standards, without taking the randomness of the impact velocity and angle at the real world situation into consideration. This often leads to the optimization results that converge to the boundary constraints, thus cannot meet the reliability requirements of the product design. Structure members of B-pillar (e.g. inner panel, outer panel, and the reinforcing plate) play a major role in the side impact safety performance. This paper dealt with optimization of B-pillar by considering its dimensions and materials as the design variables, and the impact velocity and angle from real-world traffic accident conditions as the random variable inputs. Using a combination of design of experiment, response surface models, reliability theory and the reliability of design optimization method, a B-pillar was constructed based on the product quality engineering.

Child Restraint Systems (CRS), when used properly, can effectively avoid or reduce injury for children in motor vehicle crashes. To deal with the problems of the high rate of misuse of the CRS and submarining in frontal crashes when child occupants using traditional vehicle seat belts, a novel integrated child safety seat (ICSS) with a four-point seat belt and a ring-shaped lap belt was developed in this study. It is easy to operate and has lower rate of misuse. To study the protection performance of the newly developed ICSS in frontal crashes, a sled test and a series of simulations were conducted. The frontal impact sled test was conducted according to the European regulation ECE R44, which includes a Q6 anthropomorphic test device (ATD) and the impact velocity is 50 km/h. The simulation model included the ICSS model and the Q6 ATD model was developed in the MADYMO software, and the simulation model was validated by the sled test.

Farm workers experience a very high incidence of injuries leading to physical and cognitive (strokes, TBI) disabilities. Since 1991, the AgrAbility Project 2 and its staff have provided direct assistance and education to many U.S. farmers and farm workers. If farmers, ranchers or farm workers who become disabled continue to be employed in agriculture, often their agricultural operation must be modified and/or agricultural machinery must be modified or adaptive equipment purchased to meet their new needs. Some common tractor modifications include operator lifts, hand controls, added/modified steps and handrails, automated hitches, and custom seating. Some modifications are commercially available but others are done on an individual need basis. AgrAbility staff would welcome the opportunity to work closer with farm equipment manufacturers to create modifications that would make farming and ranching easier and safer for all.

With the development of active safety technology, effort has gradually shifted to preventing or minimizing car crashes. Automatic Emergency Braking Technology (AEB) can avoid accidents by warning and even automatic braking, but there is a contradiction between the accompanying occupant out-of-position and traditional passive safety design. In addition, the 2025 version of C-NCAP plans to add neck injury assessment requirements for AEB [1]. In order to study the kinematic response of the occupant's neck under AEB, a neck finite element model with active muscle force is established in this paper. Firstly, the open-source THOR-50M neck geometric model is used for finite element discretization. Secondly, the neck FE model of THOR-50M is verified through the qualification procedure of the NHTSA standard. Thirdly, according to the geometric features of human neck muscles in Zygote Body database, the neck muscle parameters are preliminarily determined.

An autonomous emergency braking (AEB) system can detect emergency conditions using sensors (e.g., radar and camera) to automatically activate the braking actuator without driver input. However, during the hard braking phase, crash conditions for the restraint system can easily change (e.g., vehicle velocity and occupant position), causing an out-of-position (OOP) phenomenon, especially for unbelted occupants entering the airbag deployment range, which may lead to more severe injuries than in a normal position. A critical step in reducing the injury of unbelted occupants would be to design an AEB system while considering the effect of deployed airbags on the occupants. Thus far, few studies have paid attention to the compatibility between AEB and airbag systems for unbelted occupants. This study aims to provide a method that combines AEB and airbag systems to explore the potential injury reduction capabilities for unbelted occupants.

In order to provide an improved countermeasure for occupant protection, a new type of active reversible preload seatbelt (ARPS) is presented in this paper. The ARPS is capable of protecting occupants by reducing injuries during frontal collisions. ARPS retracts seatbelt webbing by activating an electric motor attached to the seatbelt retractor. FCW (Forward Collision Warning) and LDW (Lane Departure Warning) provide signals as a trigger to activate the electric motor to retract the seatbelt webbing, thus making the occupant restraint system work more effectively in a crash. It also helps reduce occupant’s forward movement during impact process via braking. Four important factors such as preload force, preload velocity and the length and timing of webbing retraction play influential roles in performance of the ARPS. This paper focuses on studying preload performance of ARPS under various test conditions to investigate effects of the aforementioned factors.

Lightweight automotive body can be obtained by developing new body constructions, using lightweight materials and structural optimizations, etc. Usually, lighter materials and structural optimizations are main aspects considered in lightweight automotive body engineering. In fact, material costs and manufacturability play more important roles than others in lightweight design. Three lightweight design approaches are considered. The first approach of lightweight design is to replace steels with lighter materials using equal rigidity design method. The second approach is a single objective optimization of mass reduction with materials selection and cost penalty. The third approach is a multi-objective optimization of mass reduction and cost reduction using multi-material concept. These three approaches are applied to an automotive body design problem considering the side impact. Different optimization methods are used to obtain different results.

Air spring due to its superior ride comfort performance has been widely used in distance passenger transporting vehicles. Since the requirements for ride comfort and handling performance are contradict to each other, handling performance and even roll stability are sacrificed to some extent to obtain good ride comfort. Due to the complex terrain and limited manufacturing level, in the past several years, bus rollover accidents with serious casualties have been reported frequently and bus safety has attracted more and more attention from bus manufacturers in China. On one hand the bus standards have to be raised, and on the other hand, novel solutions which can effectively improve the roll stability of air spring bus are needed to replace the inadequacy of anti-roll bars.

Appropriate spray modeling in multidimensional simulations of diesel engines is well known to affect the overall accuracy of the results. More and more accurate models are being developed to deal with drop dynamics, breakup, collisions, and vaporization/multiphase processes; the latter ones being the most computationally demanding. In fact, in parallel calculations, the droplets occupy a physical region of the in-cylinder domain, which is generally very different than the topology-driven finite-volume mesh decomposition. This makes the CPU decomposition of the spray cloud severely uneven when many CPUs are employed, yielding poor parallel performance of the spray computation. Furthermore, mesh-independent models such as collision calculations require checking of each possible droplet pair, which leads to a practically intractable O(np2/2) computational cost, np being the total number of droplets in the spray cloud, and additional overhead for parallel communications.

Due to the variation of compartment design and occupant’s posture in self-driving cars, there is a new and major challenge for occupant protection. In particular, the studies on occupant restraint systems used in the self-driving car have been significantly delayed compared to the development of the autonomous technologies. In this paper, a numerical study was conducted to investigate the effectiveness of three typical restraint systems on the driver protection in three different scenarios.

Recreational Off-Highway Vehicles (ROVs), since their introduction onto the market in the late-1990s, have been related to over 300 fatalities with the majority occurring in vehicle rollover. In recent years several organizations made attempts to improve ROV safety. This paper is intended to evaluate ejection mitigation measures considered by the ROV manufacturers. Evaluated countermeasures include two types of occupant restraints (three and four point) and two structural barriers (torso bar, door with net). The Rollover protection structure (ROPS) provided by the manufacturer was attached to a Dynamic Rollover Test System (DRoTS), and a full factorial series of roll/drop/catch tests was performed. The ROV buck was equipped with two Hybrid III dummies, a 5th percentile female and a 95th percentile male. Additionally, occupant and vehicle kinematics were recorded using optoelectronic stereophotogrammetric camera system.