Browse Topic: Crashes

Items (6,150)

Development and Validation of Rear Head Surround Foam Performance Specification for Stock Car Racing

2025-01-8353To be published on 04/01/2025

Over the last two decades many improvements have been made in stock car racing driver safety. The head surround of the NASCAR (National Association for Stock Car Auto Racing, LLC) seating environment serves as an effective restraint for head protection during lateral and rear impacts. However, previous rear head foam material specifications did not address low severity impacts that occur frequently during typical driving, such as race restart vehicle nose to tail contact. This study focused on developing a test methodology for comprehensive evaluation of rear head surround foam materials for repeated helmet-to-foam impacts of varying severity. Specifically, this study aimed to formulate a specification that maintains previous material performance at high speed, while decreasing head accelerations at low speed. Quasi-static and dynamic drop tower testing of sample materials was used to analyze the energy absorption capabilities of various foams and served to develop finite element

Gray, Alexandra N., Harper, Matthew G., Mukherjee, Sayak, Patalak, John P.

Analysis and Comparison of Metrics to Assess Submarining Behavior with the Hybrid III 5th Percentile Dummy in the Rear Seat

2025-01-8711To be published on 04/01/2025

Real-world data show that abdominal loading due to a poor pelvis-belt restraint interaction is one of the primary causes of injury in belted rear-seat occupants, highlighting the importance of being able to assess it in crash tests. This study analyzes the phenomenon of submarining using video, time histories, and statistical analysis of data from a Hybrid III 5th female dummy seated in the rear seat of passenger vehicles in moderate overlap frontal crash tests. This study also proposes different metrics that can be used for detecting submarining in full-scale crash tests. The results show that apart from the high-speed videos, when comparing time-series graphs of various metrics, using a combination of iliac and lap belt loads was the most reliable method for detecting submarining. Five metrics from the dynamic sensors (the maximum iliac moment, maximum iliac force drop in 1 ms, time for 80% drop from peak iliac force, maximum pelvis rotation, and lumbar shear force) were all

Jagtap, Sushant R, Jermakian, Jessica S, Edwards, Marcy A

Quantifying the uncertainty in bicycle-computer speed measurements

2025-01-8701To be published on 04/01/2025

The goal of this study is to quantify the uncertainty in bicycle computer measurements of speed. We acquired 100+ hours of data at 1-second intervals simultaneously from three Garmin Edge 530 computers mounted to the same handlebars during road cycling in rural and urban environments. Each computer recorded speed data using a different method: One unit was paired to a Garmin GSC 10 speed-and-cadence sensor (wheel rotation based), a second unit was paired to Garmin Speed Sensor 2 and Cadence Sensor 2 (accelerometer based), and a third unit was not paired to any remote sensors and relied on the device’s GPS position to calculate speed (GPS based). Based on these data, we generated probability distributions that quantify the uncertainty in the accelerometer based and GPS based speed measurements. This study provides foundational information regarding the appropriate methods to quantify the uncertainty in bicycle-computer speed data and to probabilistically interpret these data for

Booth, Gabrielle R., Siegmund, Gunter P.

Bicycle Pitch-over Reconstruction Analysis

2025-01-8684To be published on 04/01/2025

During a pitch-over event, the forward momentum of the combined bicycle and rider is suddenly impeded at the front tire and front axle causing the rider and bicycle to rotate about the bicycle front structures and also possibly propelling the rider forward. A pitch-over event can result in significant injuries to the rider. This paper presents the examination of the pitch-over of a bicycle by approaching the event using two different methods over what has been published previously. One method uses Newton’s 2nd Law directly and the other method uses the principle of impulse and momentum, the integrated form of Newton’s 2nd Law. The two methods provide useful equations, contributing to current literature on the topic of reconstructing and analyzing bicycle pitch-over incidents. The analysis is supplemented with Madymo simulation models to evaluate the kinematics and kinetics of the bicycle and rider interacting with front wheel obstructions of different heights. The effect of variables

Brach, R. Matthew, Kelley, Mireille, Van Poppel, Jon

Analysis of the Event Data Recorder vehicle system data of a GM Vehicle Intelligence Platform Airbag Control Module (SDM50

2025-01-8714To be published on 04/01/2025

The primary function of an Airbag Control Module (ACM), referred to as the Sensing and Diagnostic Module (SDM) by General Motors (GM), is to detect crashes, discriminate crashes, evaluate crash severities, deploy the appropriate restraints, including airbags and pretensioners, and perform system diagnostics. A secondary function of the SDM is to act as an Event Data Recorder (EDR) which records data during the time periods just prior to (pre-crash) and during a crash event. This data consists of restraint and vehicle system data which is collected, processed, and stored in the EDR. Data stored in the EDR is intended to be retrieved after a crash. This data provides operational information on the vehicle’s occupant protection system and other vehicle systems to assess system performance, aid in crash reconstruction, and support improved vehicle safety. A series of vehicle test maneuvers were conducted while injecting a non-deployment crash pulse directly into the SDM to cause the SDM to

Smyth, Brian, Crosby, Charles L, Bickhaus, Ryan, Smith, James, Edmunds, Dustin, Floyd, Donald, Modi, Vipul, Outlaw, RaShawndra D., Wright, Jeff

Study on the Impact of Vehicle Pitch During Braking on Pedestrian Leg Injuries

2025-01-8741To be published on 04/01/2025

With the increasing prevalence of Automatic Emergency Braking Systems (AEB) in vehicles, their performance in actual collision accidents has garnered increasing attention. In the context of Active Emergency Braking (AEB) systems, the pitch angle of a vehicle can significantly alter the nature of collisions with pedestrians. Typically, during such collisions, the pedestrian's legs are the first to come into contact with the vehicle's front structure, leading to a noticeable change in the point of impact. Thus, to investigate the differences in leg injuries to pedestrians under various pitch angles of vehicles when AEB is activated, this study employs the Total Human Model for Safety (THUMS) pedestrian finite element model, sensors were established at the leg location based on the Advanced Pedestrian Legform Impactor (aPLI), and a corresponding vehicle finite element model was used for simulation, analyzing the dynamic responses of the pedestrian finite element model at different pitch

Hong, Cheng, YE, BIN, Zhan, Zhenfei, Liu, Yu, Wan, Xinming, Hao, Haizhou

Fuzzy Sliding Mode Control of Intelligent Electric Vehicles Based on Phase Plane Stability Domain Boundaries

2025-01-8802To be published on 04/01/2025

In order to effectively improve the chassis handling stability and driving safety of intelligent electric vehicles (IEVs), especially in combing nonlinear observer and chassis control for improving road handling. Simultaneously, uncertainty with system input, are always existing, e.g., variable control boundary, varying road input or control parameters. Due to the higher fatality rate caused by variable factors, how to precisely chose and enforce the reasonable chassis prescribed performance control strategy of IEVs become a hot topic in both academia and industry. To issue the above mentioned, a fuzzy sliding mode control method based on phase plane stability domain is proposed to enhance the vehicle’s chassis performance during complex driving scenarios. Firstly, a two-degree-of-freedom vehicle dynamics model, accounting for tire non-linearity, was established. Secondly, combing with phase plane theory, the stability domain boundary of vehicle yaw rate and side-slip phase plane based

Liao, Yinsheng, Wang, Zhenfeng, Guo, Fenghuan, Deng, Weili, Zhang, Zhijie, Zhao, Binggen, Zhao, Gaoming

A Sled Test Methodology for 25% Offset Crash Tests

2025-01-8737To be published on 04/01/2025

Sled crash tests are an important tool to develop automotive restraint systems. Compared with full-scale crash tests, the sled test has a shorter development cycle of the restraint system and lower cost. The objective of the present study is to create a cost-effective sled test methodology, calculate the optimal static yaw angle and loading curves, and analyze the motion response and injuries of the dummy in the small-offset crash test. The effectiveness of the proposed methodology was verified under two typical Small Overlap Frontal Crash (SOFC) modes “energy-absorption” and “sideswipe”. The results show that with the calculated yaw angle α, the head HIC was different from the SOFC model, but all remaining indices were within 5% of the injury criteria . All International Organization for Standardization (ISO) values between the combined accelerations of all parts of the dummy and those of the basic model exceeded 0.75, and some values were above 0.8. Therefore, the proposed sled test

Yu, Liu, Chen, Jianzhuo, Wan, Ming Xin, Fan, Tiqiang, Yang, Peilong, Nie, Zhenlong, Ren, Lihai, Cheng, James Chih

A study on affections of Different Skull-brain Interface Modeling Approaches on Intracranial Responses in Finite Element Analysis

2025-01-8733To be published on 04/01/2025

The mechanical behaviors of brain-skull interface are rather complex and difficult to understand, and various simplified connecting or contacting methods are usually used to simulate the interactions between the brain and skull in the current head finite element (FE) models. Considering the modeling approach of the brain-skull interface determines how loads are transmitted from skull to brain and affects on the intracranial brain responses, therefore, it is essential to study the affections of different brain-skull interface modeling approaches on intracranial brain responses and obtain an accurate load transmission mechanism to study brain injuries. In this study, the head FE model which is a part of the Advanced Chinese Human Body Models (AC-HUMs) is used and some modifications were made on the modeling method of the brain-skull interface in this head FE model. First, head FE model with several different brain-skull interface modeling methods including tied contact, shared nodes

Gan, Qiuyu, Junpeng, Xu, Jiang, Binhui, Zhou, Runzhou, Zhang, Liying

The Influence of Reclined Seatback Angles on Occupant Injury Risks in Frontal Impacts

2025-01-8732To be published on 04/01/2025

The reclined seatbacks will be increasingly used with the advanced technologies of the intelligent automobile. The occupant collision protection must rise to the challenge facing to the new impact scenarios. It is necessary to understand the injury mechanisms of the reclined occupants in order to design the resistant system and testing protection regulations. In this study, the Frontal Full Width Impact (FRB) and Mobile Progressive Deformable Barrier Frontal Impact (MPDB) tests were conducted as specified in China New Car Assessment Programme (C-NCAP, 2021 version). The simulation used the biomechanical model of the 5th female occupant exhibiting the detailed anatomical structures and a seat model with large-angle seatback. The occupant injury risks and mechanisms with 25°, 45° and 60° seating postures were investigated by analyzing the kinematic and biomechanical parameters, and the influence of the seatback angle on occupant injury was discussed. The results indicate that reclined

Wang, Yanxin, Pan, Ruyang, Lin, Yuyang, Liu, Yutao, He, Lijuan, Wang, Zhenqiang, zhu, he, Liu, Chong, Li, Kun, Lv, Wenle

Characterisation and variabilities of aerosols produced by tyres rotating on wet surfaces

2025-01-8763To be published on 04/01/2025

Understanding the formation and behaviour of aerosols generated by vehicles traveling on wet surfaces is crucial due to their impact on vehicle soiling, visibility, and autonomous driving. These aerosols can reduce visibility for other drivers, contribute to traffic accidents, and reduce the operational capabilities of sensors for driving assistance systems and future autonomous vehicles. Despite the importance of understanding the physical properties of these aerosols is crucial for testing and validating sensors for environmental perception and recognition, field data on this topic is scarce. The formation and behaviour of these aerosols are complex. A fraction of the trailing droplets and ligaments originates directly from the tyres, while the remainder is generated upon the impact of the particles ejected from the tyres with the vehicle’s surfaces, resulting in either coalescence or further disintegration. Aerodynamic forces also significantly influence the formation of these

Otxoterena, Paul, Kallhammer, Jan-Erik, Eriksson, Peter, Ronelov, Erik

The Effect of Tracker and Control Point Distributions on the Accuracy of Vehicle Position and Speed Estimates from Dash Camera Video

2025-01-8697To be published on 04/01/2025

Dash cameras (dashcams) can provide collision reconstructionists with quantifiable vehicle position and speed estimates. These estimates are achieved by tracking 2D video features with camera tracking software to solve for the camera position history and then calculating speed from the position-time history. Not all scenes have the same geometric features in quality or abundance. In this study, we quantified how the accuracy of vehicle position and speed estimates from dashcam video varied with large differences in 2D tracker distributions that mimicked the continuum between barren environments and feature-rich environments. We used video from a dashcam mounted in a vehicle undergoing straight-line emergency braking. The surrounding environment had abundant trackable features, including road markings, street lights, signs, trees, and buildings on both sides. We first created a reference solution using SynthEyes, a 3D object and camera tracking program, and all of the available features

Young, Cole, Ahrens, Matthew, Siegmund, Gunter P., Flynn, Thomas

Validation of SynthEyes for use in Collision Reconstruction

2025-01-8688To be published on 04/01/2025

Accurate reconstruction of vehicle collisions is critical for understanding incident dynamics and informing safety improvements. Traditionally, vehicle speed from dashcam footage has been approximated by estimating the time duration and distance traveled as the vehicle passes between reference objects. This method limits the resolution of the speed profile to an average speed over given intervals, minimizing vehicle accelerations. A more detailed speed profile can be calculated by tracking the vehicle’s position in each video frame; however, this method is time-consuming, can introduce positional error and variable frame rate noise, and is often constrained by the availability of external trackable features in the surrounding environment. Motion tracking software, widely used in the visual effects industry to track camera positions, has been adopted by some collision reconstructionist for determining vehicle speed from video. This study examines the accuracy and reliability of using

Perera, Nishan, Griffiths, Harrison, Prentice, Greg

Research on the Boundary of Pedestrian Leg Impactor Test in Low-Speed Passive and Active Conditions

2025-01-8735To be published on 04/01/2025

With the widespread application of the Automatic Emergency Braking System (AEB) in vehicles, its impact on pedestrian safety has received increasing attention. However, after the intervention of AEB, the kinematic characteristics of pedestrian leg collisions and their corresponding biological injury responses also change. At the same time, in order to accurately evaluate the pedestrian protection performance of vehicles, the current assessment regulations generally use advanced pedestrian protection leg impactors (aPLI) and rigid leg impactors (TRL) to simulate the movement and injury conditions of pedestrian legs. Based on this, in order to explore the collision boundary conditions and changes in injury between vehicles and APLI and TRL leg impactors under the action of AEB, this paper first analyzes the current passive and active assessment conditions. Secondly, the simulation software LS-DYNA is used to build a finite element model of APLI and TRL impactor-vehicle collisions to

YE, BIN, Hong, Cheng, Wan, Xinming, Liu, Yu, Cheng, James, LONG, YONGCHENG, Hao, Haizhou

Lattice based Localized Energy Absorber for Improved Vulnerable Road User Performance for a Vehicle

2025-01-8723To be published on 04/01/2025

A passenger vehicle hood is designed to meet Vulnerable Road User (VRU) regulatory requirements and Consumer metric targets. Generally, hood inner design and its reinforcements, along with deformable space available under the hood are the main enablers to meet the Head Impact performance targets. However, cross functional balancing requirements like hood stiffness and packaging space constraints can lead to higher Head Injury Criteria (HIC) scores, particularly when secondary impacts are present. In such cases, a localized energy absorber is utilized to absorb the impact energy to reduce HIC within the target value. The current localized energy absorber solutions include the usage of flexible metal brackets, plastic absorbers etc. which has limited energy absorbing capacity and tuning capability. This paper focuses on usage of a novel 3D printed energy absorbers, based on various kind of lattice structures. These absorbers are either sandwiched between hood inner and the outer or are

Kinila, Vivekananda, Agarwal, Varun, V S, Rajamanickam, Tripathy, Biswajit, Gupta, Vishal

The Biomechanical Effects of Neck and Back Cushion/Support/Pillow Devices in Low-Speed Rear Impacts

2025-01-8728To be published on 04/01/2025

There are numerous commercially available neck and back support/cushion/pillow devices which are oftentimes attached to seats by vehicle owners. To our knowledge, there has been no published research on the biomechanical effects of these devices in low-speed rear impact exposures. In this study, a series of 54 simulated low-speed rear impact tests were conducted using a validated remote-controlled crash sled system. All tests utilized an instrumented rear impact anthropomorphic test device (BioRID II) restrained using a 3-point seatbelt system in a 2018 Toyota Camry LE driver’s seat. Two delta-V ranges were used for the study: a lower range from 7.2 to 8.0 kph (4.5 to 5.0 mph) and a higher range from 10.5 to 11.3 kph (6.5 to 7.0 mph). Six neck only devices, one combination neck and back device, and three back only devices were assessed. Two tests per delta-V range for each device and each device adjustment position were conducted, in addition to control tests without any devices

Phan, Andrew, Gross, Jamie, Umale, Sagar, Crowley, Shannon, Glasser, Gabriel, Furbish, Christopher

A Chronology of Research and Events To-Date Significant to Occupant Protection in Rear-End Automobile Impacts

2025-01-8725To be published on 04/01/2025

Theory and principles of occupant protection for automobiles in rear-end collisions have experienced significant evolution over the decades. Performance of the seatback, specifically the stiffness of the structure, during such a collision has been a subject of particular interest and debate among design engineers, accident reconstruction experts, critics, etc. The majority of current seat designs rely on plastic deformation of the seatback structure to protect the occupant from the dynamics of the crash. In attempt to highlight and provide background information for understanding this subject, this work highlights significant events, research, and publications over the past five decades to illustrate how this subject, automobile design, government regulation and public opinion has evolved. It is observed that technology and design for improving rear-impact protection has received less attention than collisions of other principal directions of force. The different types of

Warner, Wyatt

Numerical Modeling of a Sandwich Structure Integrated with Shear Thickening Fluid (STF) for Impact Energy Absorption

2025-01-8745To be published on 04/01/2025

Shear Thickening Fluid (STF) exhibits tunable stiffness under varying loading velocities, making it an ideal candidate for energy absorption in transportation systems subjected to complex loading conditions, such as crash scenarios. Recent research highlights that integrating STF with conventional structures can significantly enhance overall energy absorption performance. In this study, we developed a novel sandwich plate by combining a newly designed bio-inspired 3D periodic structure with STF, aiming to create an advanced energy absorber. A finite element model of this system was developed and validated against experimental data. Using this numerical model, we conducted comprehensive impact simulations to investigate the effects of impact velocity and STF viscosity on key structural responses, including peak and mean stress, as well as energy absorption. The contributions of both the fluid and solid components were analyzed. Our findings indicate that the integrated structure

Zhu, Feng, Deb, Anindya

Biofidelity evaluation of AC-HUM pedestrian model based on generic sedan Buck model

2025-01-8743To be published on 04/01/2025

Objective: This study aims to evaluate the biofidelity of the Advanced Chinese Human Body Model (AC-HUM) by utilizing a generic sedan Buck model and postmortem human subjects (PMHS) tests. Methods: The boundary conditions of the simulation are derived from the PMHS test with Buck vehicle. The methodology involved the pose adjustment of the upper and lower extremities of AC-HUM, executed through a pre-simulation approach. Subsequently, a 200 milliseconds full-body pedestrian crash simulation was conducted by integrating the Buck vehicle model with the AC-HUM pedestrian model. The trajectories of AC-HUM during the period from initial position to head impact were recorded, including the Head CG, T1, T8 and pelvis. Based on the knee joint, the biofidelity corridors of trajectories in PMHS test were scaled to match the Chinese 50th percentile male to assess the biofidelity of AC-HUM's motion trajectories. Furthermore, the biomechanical responses and injury prediction results of AC-HUM were

Qian, Jiaqi, Wang, Qiang, LIU, YU, Wu, Xiaofan, Huida, Zhang, Bai, Zhonghao

Multi-objective optimization of the electric bus body frame based on the PSO-BP-MOMVO approach

2025-01-8652To be published on 04/01/2025

This paper focuses on the design optimization of a commercial electric bus body frame with steel-aluminum heterogeneous material orienting the performances of strength, crashworthiness and body lightweight. First, the finite element (FE) model of the body frame is established for static and side impact analysis, and the body frame is partitioned into several overall regions according to the thickness distribution of the components. The thickness of each region is regarded as the variable for the sensitivity analysis by combining the relative sensitivity method and the Sobol index method, and nine variables to which the performance indexes are more sensitive are selected as the final design variables for design optimization. Then the surrogate models are developed, and in order to improve the accuracy of the surrogate models, a model-constructing method called the particle swarm optimization BP neural network (PSO-BP) data regression prediction is proposed and formulated. In this method

Yang, Xiujian, Tian, Dekuan, Cui, Yan, Lin, Qiang, Song, Yi

Enhanced Secondary Crash Classification through Functional Class-Based Weighting and Hybrid Machine Learning Models

2025-01-8207To be published on 04/01/2025

Road safety and traffic management face significant challenges due to secondary crashes, which frequently cause more traffic, delays, and collisions. The importance of different types of roads is often overlooked by traditional methods for anticipating secondary crashes, which can result in suboptimal predictions and reaction plans. This research provides a novel method that combines a hybrid machine-learning model with a functional class-based weighting strategy to classify secondary crashes. The functional classes of the dataset are classified as interstates, arterial roads, collector roads, and local roads. The dataset also includes comprehensive crash narratives and various road attributes. Each functional class is assigned a weight that reflects its proportional importance in the likelihood of a subsequent crash, based on historical data and road usage patterns. After that, this weighting technique is integrated into a hybrid model architecture that trains a Random Forest model on

Patil, Mayur, Marik PE, Stephanie

DESIGN METHODOLODY AND EVALUATION TECHNIQUES FOR PELVIC PUSHER ENERGY ABSORPTION PAD

2025-01-8615To be published on 04/01/2025

Pelvic Pusher Energy Absorption Pad in a vehicle saves the occupant from pelvic injuries in the event of a crash, especially side or Pole Crash. This Pelvic Pusher Pad plays a crucial role in absorbing the impact energy from the Body side and minimising the impact to the occupant. Positioning of Pelvic Pusher Pad with respect to Occupant Manikin position and torso angle, stiffening criteria for the energy absorption pad, Maximum Force and Energy Absorption target setting methodology and Evaluation methods through CAE and Part Level Physical Validations are all discussed in detail. Pelvic Pusher Pad are of various types such as EPP moulded, Blow Moulded or Injection Moulded and the criteria differ for each type. For EPP moulded type, Based on the EPP Grade, S-S Graph gets converted to F-S Graph and validated accordingly. F-S Graph for a test vehicle is generated through sled test where the sled is made to impact the pelvis of ES2 Dummy at a constant velocity and the F-S Graph is

S M, Rahul, d, ANANTHA, Kakani, Phani Kumar, Malliboina, Mahendra

Speed Determination Using Audio Analysis of Dash Camera Video from Passenger Vehicle Tires Frequencies for Vehicle Accident Reconstruction

2025-01-8682To be published on 04/01/2025

Prior research has validated a reliable method of determining speed using the audio data and a known wheelbase of a test vehicle captured by dash camera audio. However, it has been found that dash camera audio may record an unknown frequency that varies with the test vehicle’s speed. Investigating the origin of the unknown varying frequency revealed the horn effect phenomena, which has been well known research by the tire industry. Independent research identified a frequency generated by the rotating tires when a certain speed threshold was reached by the test vehicle. The research concluded that the tread pattern of the tire in contact with the roadway surface generated a frequency that varied with vehicle speed. However, research using the audio from a dash camera to determine vehicle speed from that specific varying frequency for forensic purposes has not been investigated. The purpose of this study was to outline, test, and confirm the source of the varying frequency as a valid

Vega, Henry V., Ngo, Long Justin, Hatab, Ziad, Cornetto, Anthony, Engleman, Krystina, Hunter, Eric

A Method for Lens Distortion Correction of Algorithmically Altered Images

2025-01-8680To be published on 04/01/2025

Photogrammetry is a commonly used type of analysis in accident reconstruction because it allows the position and orientation of vehicles to be quantified as seen in photographic and video evidence. Lens distortion is an important consideration when analyzing photographs and video through photogrammetry. Failure to account for lens distortion can result in inaccurate spatial measurements, particularly when elements of interest are located toward the edges and corners of images. A variety of methods for removing lens distortion are commonly used in photogrammetric analysis. However, these methods assume that lens distortion is solely the result of curved camera lenses and has not been altered algorithmically by the camera system. Today there are several cameras on the market that algorithmically alter images before saving them. These camera systems use proprietary distortion correction features to visually change photographs and videos before they can be viewed. A video or photograph

Pittman, Kathleen, Mockensturm, Eric, Buckman, Taylor, White, Kirsten

STUDY ON THE IMPROVEMENT OF PEDESTRIAN AND VEHICLE VISIBILITY BY GEOMETRIC PATTERNS PROJECTION LIGHTING

2025-01-8663To be published on 04/01/2025

A high percentage of pedestrian fatalities in traffic accidents occur at night. Although using high beams at night can enhance pedestrian visibility for drivers, it also presents the issue of increased glare for pedestrian. In this study, the researchers devised a geometric patterns projection lighting using projection technology, designed to reduce glare for pedestrians while enhancing the visibility of pedestrians and approaching vehicles. This study explores the effectiveness of a geometric patterns projection lighting compared to traditional Low beam and High beam headlights in enhancing pedestrian visibility during nighttime driving conditions. Conducted at Dynamic Research Inc.'s closed-course facility, the experiment involved 20 drivers who were exposed to each headlight type while performing specific tasks, including headlight noticeability, glare assessment, and pedestrian detection. The geometric patterns projection lighting, characterized by dynamic intersecting light

Kawamura, Kazuyuki, Oshida, Kei

Design and Optimization of a Novel Aluminum-Intensive Spaceframe-Based Electric Mailvan Prototype Driven by CAE

2025-01-8323To be published on 04/01/2025

Despite the known advantages of aluminum in terms of its lower density and comparable strength-to-weight as well as stiffness-to-weight ratios as those of steel, superior recyclability and high residual value, etc., there are only a handful of vehicles in global markets, mostly outside the reach of the common man, made primarily of aluminum. As cost of material and joining of parts is a deterrent in large scale adoption of aluminum as a material of choice for vehicle body design, a novel architecture is necessary for minimizing weight, maximizing performance and lowering cost of tooling. Additionally, a lightweight vehicle cannot be behind in terms of crash safety compared to its predominantly steel body-based counterparts. With these objectives in mind, a novel aluminum-intensive electric mailvan based on a spaceframe body architecture comprised mainly of low-cost extrusions has been designed and prototyped primarily driven by CAE. The design methodology consists of selective testing

Deb, Anindya, Karthika, M R

Sideswipe Testing with an Instrumented Hybrid III Anthropomorphic Test Device (ATD

2025-01-8702To be published on 04/01/2025

Sideswipe collisions pose a challenge to analyze for several reasons, however the most significant factor is that the vehicles do not reach a common velocity at impact. To better understand the dynamics of a sideswipe, vehicle testing can be performed to find the relationship between variables related to the impact, such as closing speed, relative angle, and overlap depth. This paper discusses data collected for three oblique (sideswipe) impact tests conducted by Calspan Corporation at their Transportation Test Operations facility in Buffalo, New York. The tests were conducted using a 2015 Toyota Corolla as the bullet vehicle, which impacted a stationary 2016 Ford Transit van. The Corolla was towed into the Transit at relative angles ranging from 8 to 15 degrees and at velocities of 5 to 20 mph. Two different (but identical) Toyota Corollas and Ford Transit vans were used during the testing series, depending on the test conditions. One instrumented Hybrid III 5th dummy was placed in

Danaher, David, Neale, William, Donaldson, Andrew, McDonough, Sean, Cochran, Reece, Reed, Titus

Driver Distraction Recognition Based on the Information Bottleneck Theory and Graph Convolutional Networks

2025-01-8112To be published on 04/01/2025

Driver distraction remains a leading cause of traffic accidents, making its recognition critical for enhancing road safety. In this paper, we propose a novel method that combines the Information Bottleneck (IB) theory with Graph Convolutional Networks (GCNs) to address the challenge of driver distraction recognition. Our approach introduces a 2D pose estimation-based action recognition network that effectively enhances the retention of relevant information within neural networks, compensating for the limited data typically available in real-world driving scenarios. The network is further refined by integrating the CTR-GCN (Channel-wise Topology Refinement Graph Convolutional Network), which models the dynamic spatial-temporal relationships of human skeletal data. This enables precise detection of distraction behaviors, such as using a mobile phone, drinking water, or adjusting in-vehicle controls, even under constrained input conditions. The IB theory is applied to optimize the trade

Zhang, Ji, Bai, Yakun

A Collision Risk Assessment-Based Longitudinal Collision Avoidance Control Strategy for Tractor Semi-Trailers with Slip Ratio Control

2025-01-8037To be published on 04/01/2025

With the advancement of intelligent transportation and smart logistics systems, tractor semi-trailers have gradually become one of the primary modes of transport due to their substantial cargo capacity. However, the ongoing increase in the number of tractor semi-trailers has also introduced traffic safety issues. Due to their significant spring mass and strong body strength, accidents involving tractor semi-trailers often result in severe consequences. Active collision avoidance control strategies provide assurance for vehicle safety. However, existing research predominantly focuses on passenger cars and small commercial vehicles. Research specifically addressing tractor semi-trailers, which have longer bodies and more complex dynamic characteristics, is relatively sparse. Therefore, this paper proposes a collision risk assessment-based longitudinal collision avoidance control strategy for tractor semi-trailers with slip ratio control. Firstly, the paper introduces the braking

Yan, Yang, Zheng, Hongyu

Safe Cooperative Control Framework for Highway On-Ramp Merging

2025-01-8024To be published on 04/01/2025

The development of connected and automated vehicles (CAVs) is rapidly increasing in the next generation and the automotive industry is dedicated to enhancing the safety and efficiency of CAVs. A cooperative control strategy helps CAVs to collaborate and share information among the neighboring CAVs, improving efficiency, optimizing traffic flow, and enhancing safety. This research proposes a safe cooperative control framework for CAVs designed for highway merging applications. In the urban transportation system, highway merging scenarios are high-risk collision zone, and the CAVs on the main and merging lanes should collaborate to avoid potential accidents. In the proposed framework, the on-ramp CAVs merge at 40 mph within the same and opposite directions to the main lane CAVs. The proposed framework includes the consensus controller, safety filter, and quadratic programming (QP) optimization method. The consensus controller incorporates the communication between CAVs and designs the

Chang, PeiYu, Bhatti, Sidra, Javed, Nur Uddin, Ahmed, Qadeer

The influence of out-of-position displacement during emergency braking on occupant whiplash injury in subsequent rear-end collisions

2025-01-8720To be published on 04/01/2025

During emergency braking condition, the occupant inside the vehicle will move forward due to the iner-tia, deviating from the standard upright seating posture assumed in the design of restraint systems. Pre-vious studies have focused on the influence of this out-of-position displacement on occupant injuries in frontal collisions, but few attention has been paid to the effect on whiplash injury during a subsequent rear-end collision. In this study, the MADYMO simulation platform and its active human body model were used to setup a vehicle interior sled test model for rear-end collision research. By setting different braking strength (0.8 and 1.1g), the trigger time of active pretensioning seatbelt (from 0.2s before to 0.2s after the braking initiation), and the pretensioning force (from 100N to 600N), various forward out-of-position displacements of the occupant were obtained. The corresponding whiplash injury met-rics including neck shear force, tension force, and neck injury criteria

Fei, Jing, Tan, Puyuan, Zhou, Qing, Qiu, Hang, Liu, Yu

The Investigation of Upper Thorax Rib Deflections in WorldSID 50th Male ATDs in Vehicle Side Oblique Pole Tests

2025-01-8724To be published on 04/01/2025

WorldSID dummy is currently adopted extensively in vehicle regulatory testing (1) and third party evaluation testing (2) like in EURO-NCAP and C-NCAP. As one of many side impact dummies, WorldSID dummy is a highly biofidelic, advanced side impact crash test dummy. However, as testing modes are expended, there are some of observations, which affect occupant protection negatively in side impact situations. One of the observations is that the interaction between arm and thorax rib causes excessive deflection of top thorax rib in side oblique pole impact crash with a large side airbag, which has better protection to the shoulders of an occupant. This paper will present the observation of excessive top thorax rib deflection of WorldSID dummy in a side oblique pole crash testing while no such phenomena observed in a side barrier crash testing. A study of both physical and CAE testing in a side oblique pole (75 degree to longitudinal vehicle direction) crash were carried out to investigate

Liu, Chong, Chen, Shaopeng, Pan, Ruyang, Zhou, Dayong, Yang, Heping, Wang, Pengxiang

A Comparison of UAV LiDAR and Terrestrial Laser Scanner Accuracies

2025-01-8694To be published on 04/01/2025

Airborne Laser Scanning (ALS) and specifically LiDAR collected from Unmanned Aerial Vehicles (UAVs) has become an important tool for forensic site documentation. This is especially true for large, outdoor incident sites. Terrestrial Laser Scanners (TLS) are commonly used to document these large incident sites, however in comparison to TLS LiDAR, UAV LiDAR is a more efficient method for forensic service providers to document these sites. ALS is well suited for the vehicle accident reconstruction community as most roadway accident sites are accessible by UAVs. Safety may be an additional benefit of ALS as it typically requires less documentation time at the incident site and the LiDAR data is recorded from a more remote location. This research focuses on comparing the accuracy of UAV LiDAR to TLS LiDAR and evaluates efficiency of data capture. For the purposes of this study, three site locations with differing roadway geometry were chosen and documented with both TLS and UAV LiDAR. The

Foltz, Steve, Terpstra, Toby, Clarson, Julia

Accuracy of Mobile of Phone LiDAR on Crashed Accident Vehicles

2025-01-8692To be published on 04/01/2025

Apple’s mobile phone LiDAR capabilities can be used with multiple software applications to capture the geometry of vehicles and smaller objects. The results from differing software have been previously researched and compared to traditional ground-based LiDAR. However, results were inconsistent across software applications, with some software being more accurate and others being less accurate. (Technical Paper 2023-01-0614. Miller, Hashemian, Gillihan, Benes.) This paper builds upon existing research by utilizing the updated LiDAR hardware that Apple has added to its iPhone 15 smartphone lineup. This new hardware, in combination with the software application PolyCam, was used to scan a variety of crashed vehicles. These crashed vehicles were also scanned using a FARO 3d scanners, which have been researched extensively for their accuracy. The PolyCam scans were compared to FARO scans to determine accuracy for point location and scaling. Previous research has shown that user variability

Miller, Seth Higgins, Stogsdill, Michael, McWhirter, Seth

Evaluating Consumer-Grade Technology for Accident Reconstruction: A Study of Recon3D, Luma AI, and Leica RTC360

2025-01-8689To be published on 04/01/2025

This research paper investigates the effectiveness of various tools for generating 3D point clouds in accident reconstruction. Specifically, it compares the Recon3D app on the iPhone 14 and 15 Pro Max, Luma AI’s capability of generating 3D point clouds from 360-degree vehicle videos, and the industry-standard Leica RTC360 laser scanner. The study aims to capture detailed spatial data of vehicles involved in accidents, assessing the accuracy, efficiency, and usability of these tools. Controlled experiments were conducted to evaluate the performance of each tool, comparing the generated 3D models to those produced by the Leica RTC360 laser scanner. This comparative analysis highlights the potential for consumer-grade and AI-powered technologies to democratize access to advanced accident reconstruction tools, providing significant benefits to law enforcement, insurance investigators, and accident analysts

Desai, Elvis, Stemrich, Robert

An Introduction to the Forensic Acquisition and Analysis of Mobile Device Data for Accident Reconstruction

2025-01-8706To be published on 04/01/2025

Mobile devices have become ubiquitous in modern society, and the data they store has become increasingly valuable in the field of accident reconstruction. Today's mobile devices continuously capture data about our behaviors and interactions. This paper delves into the methods of acquiring data from mobile devices, such as smartphones, and examines how this data can be utilized to reconstruct vehicular accidents, particularly those involving distracted driving. The types of data that can be extracted, including call logs, text messages, app usage history, device activity, and location data, are explored in detail. Finally, a case study is presented in which various device events are examined and location data acquired from a mobile device is compared to independent Global Positioning System (GPS) instrumentation to analyze the accuracy of the retrieved data

Burgess, Shanon, Phy, Lance, Levan, Matthew

Predicting Head Injury Criterion in Real-World Frontal Impacts

2025-01-8709To be published on 04/01/2025

Research on modeling head injury metrics and head acceleration waveforms from real-world collisions has been limited compared to vehicle crash pulses. Prior studies have used simple pulse functions to model vehicle crash pulses and have employed more complex approximations for head injury metrics. This study aimed to develop a method to predict 15 ms Head Injury Criterion (HIC15) in frontal passenger vehicle impacts using simple pulse functions, where only occupant peak head acceleration and head impact duration are known. Vehicle crash tests from the New Car Assessment Program (NCAP) were selected for frontal impacts that include driver occupants, then separated for training and testing. The resultant head acceleration-time curves of the driver Hybrid III 50th percentile male anthropomorphic test devices were collected. Rectangular, triangular, quadratic, half-sine, and half-haversine pulse functions were modeled using peak head acceleration and the duration of significant head

Westrom, Clyde, Tanczos, Rachel, Adanty, Kevin, Shimada, Sean

Active and passive security generalization algorithm and typical case analysis

2025-01-8744To be published on 04/01/2025

In order to be able to effectively predict the safety performance of vehicles and reduce the cost of enterprise safety tests, a generalized model for automotive active and passive safety simulation is proposed. The frontal driver's side collision model under AEB intervention is created by MADYMO software, and the collision acceleration obtained from the bench test is used as the model input to simulate the human body in different seating postures, and the damage values of each part of the Hybrid III 50th dummy are read, and the active-passive simulation model is established by BP neural network according to the correlation relationship between the two, and the model input is the inclination angle centered at the waist of the dummy, and the output is the damage values of each part of the dummy. The input of the model is the tilt angle centered on the waist of the dummy, and the output is the damage value of each part of the dummy. The results surface: the prediction accuracy is more

Ge, Wang

A study on affections of active neck muscle force on neck injury responses in frontal impact with Automatic Emergency Braking conditions

2025-01-8742To be published on 04/01/2025

Neck injury is one of the most common injuries in traffic accidents, and its severity is closely related to the posture of the occupant at the time of impact. In the current era of smart vehicle, the triggered AEB and the occupant's active muscle force will cause the head and neck to be out of position which has significant affections on the occurrence and severity of neck injury responses. Therefore, it is very important to study the influences of active muscle force on neck injury responses in in frontal impact with Automatic Emergency Braking conditions. Based on the geometric characteristics of human neck muscles in the Zygote Body database, the reasonable neck muscle physical parameters were obtained firstly. Then a neck finite element model (FEM) with active muscles was developed and verified its biofidelity under various impact conditions, such as frontal, side and rear-end impacts. Finally, using the neck FEM with or without active muscle force, a comparative study was

Junpeng, Xu, Gan, Qiuyu, Jiang, Binhui, Zhu, Feng

A preliminary study of occupant kinematics and injuries in a frontal crash with occupant face-to-face scenario

2025-01-8736To be published on 04/01/2025

Intelligent cockpits often feature seats that can be adjusted in multiple ways to suit different needs. This includes not only traditional adjustments (such as recline, lumbar support, and headrest positioning) but also more advanced configurations where seats can rotate, slide, or fold flat to create different cabin layouts. This paper presents a preliminary study of occupant face-to-face scenario in a 50 km/h frontal impact. Injuries of three cases, including rear-facing 50th occupant, forward facing 50th occupant and interaction between rear facing and forward facing occupants, were carried out. The injury of the occupants in vehicle are different depending on the occupant seating positions. For rear facing occupant, the primary injury is dependent on seat design while for the forward facing occupant, the primary injury caused by a larger space between two occupants, in which there is without reaction surface to support (or slow) occupant itself. The injury caused by interaction of

Liu, Chong, Li, Kun, Liu, Yutao, Lv, Xiaojiang, wang, Yonghui, Zhou, Dayong, Yang, Heping

The Effects of Collision-Related Power Loss on Toyota Safety Sense 2.5+ Event Data

2025-01-8713To be published on 04/01/2025

Toyota vehicles equipped with Toyota Safety Sense (TSS) can record detailed information surrounding various driving events, including crashes. Often, this data is employed in accident reconstruction. TSS data is comprised of three main categories: Vehicle Control History (VCH), Freeze Frame Data (FFD), and images. Because the TSS data resides in multiple ECUs, the data recording is susceptible to catastrophic power loss. In this paper, the effects of a sudden power loss on the VCH, FFD, and images are studied. Events are triggered on a TSS 2.5+ equipped vehicle by driving toward a stationary target. After system activation, a total power loss is induced at various delays after activation. Results show that there is a minimum time required after system initiation in order to obtain full VCH, FFD, and image records. Power losses occurring within this time frame produce incomplete records. Data accuracy is unaffected, even in partial records

Getz, Charles, DiSogra, Matthew, Spivey, Heath, Johnson, Taylor, Patel, Amit

Application of 1.7GPa Martensitic Steel in Dash Lower Cross Member to Enhance Automotive Frontal Impact Safety

2025-01-8218To be published on 04/01/2025

The rapid growth of electric vehicles (EVs) has led to a significant increase in vehicle mass due to the integration of large and heavy battery systems. This increase in mass has raised concerns about collision energy and the associated risks, particularly in high-speed impacts. As a consequence, crashworthiness evaluations, especially front-impact regulations, have become increasingly stringent. Crash speed between the vehicle and the Mobile Progressive Deformable Barrier (MPDB) is increasing, reflecting the growing emphasis on safety in the automotive industry. Moreover, a new frontal pole crash scenario is under consideration for future regulatory standards, highlighting the continuous evolution of crash testing protocols. To ensure occupant protection and battery safety, manufacturers have traditionally used Hot Blow Forming technology for producing closed-loop dash lower cross member components. However, this process is both costly and energy-intensive, necessitating more

Lee, Jongmin, Kim, Donghyun, JANG, MINHO, Kim, Geunho, Seongho, Yoo, Kim, Kyu-Rae

Research on Dangerous Driving Behavior Recognition Algorithm Based on LSTM

2025-01-8204To be published on 04/01/2025

To address the issue of high accident rates in road traffic due to dangerous driving behaviors, this paper proposes a recognition algorithm for dangerous driving behaviors based on Long Short-Term Memory (LSTM) networks. Compared with traditional methods, this algorithm innovatively integrates high-frequency trajectory data, historical accident data, weather data, and features of the road network to accurately extract key temporal features that influence driving behavior. By modeling the behavioral data of high-accident-prone road sections, a comprehensive risk factor is consistent with historical accident-related driving conditions, and assess risks of current driving state. The study indicates that the model, in the conditions of movement track, weather, road network and conditions with other features, can accurately predict the consistent driving states in current and historical with accidents, to achieve an accuracy rate of 85% and F1 score of 0.82. It means the model can

Huang, Yinuo

Aggregation of Cervical Loads in Rear Impact Crash Tests and Comparison to Activities of Daily Living

2025-01-8708To be published on 04/01/2025

Peak upper and lower neck load data from rear impact crash testing were reviewed, aggregated, and analyzed from over 1,800 tests of existing peer-reviewed literature and research as well as available testing conducted by the Insurance Institute for Highway Safety (IIHS) and the National Highway Traffic Safety Administration (NHTSA). Both human volunteers and anthropomorphic test devices (ATDs) were subjects of the reviewed studies and testing. Peak upper and lower neck axial forces (compression and tension), sagittal shear forces, and sagittal moments (flexion and extension) from available crash testing were reported and analyzed as functions of measured change in velocity (delta-V) ranging from approximately 3 to 60 km/h (1.9 to 37 mph). This load data was then further analyzed for possible trends amongst various testing conditions, such as seat type, ATD used, and subject seating position within the vehicle chassis and seat. The linear regressions developed from rear impact crash

Kazmierczak, Alex, Umale, Sagar, Visalli, Alyssa, Webb, Ella, Kashdan, Aryeh, Randles, Bryan, Welcher, Judson

Decelerations for vehicles with anti-lock brake systems (ABS) during wet-to-dry transitions on asphalt and concrete road surfaces

2025-01-8703To be published on 04/01/2025

The braking performance of newer anti-lock braking systems (ABS) equipped vehicles on roads with varying wetness levels is not well studied. Two late-model ABS-equipped vehicles were used to perform ABS-engaged braking tests on dry and wet asphalt and concrete surfaces from which vehicle speed and deceleration as a function of time were calculated. Tests were initially conducted on a dry surface before a water truck distributed water onto the road to create a wet road condition. A continuous series of tests were then performed until the road dried and the cycle was repeated multiple times. Across all tests of both vehicles on both road surfaces, deceleration levels generally decreased when the road was wet and returned to dry levels only when less than 25% of the road surface remained wet. Also, wet deceleration levels were high compared to the historical values used for wet roads. These findings provide a useful and readily identifiable boundary between what can be considered a dry

Miller, Ian, King, David, Siegmund, Gunter

Lightweight optimization of an electric bus body frame based on the C2oDE algorithm

2025-01-8654To be published on 04/01/2025

This work focuses on the design optimization of the electric bus body frame orienting the lightweight while ensuring the performance of stiffness, strength and crashworthiness. Based on the entropy weight-TOPSIS comprehensive contribution analysis method, the components of the bus body frame, which have significant impact on the output response of the static mode model and the rear-end collision model are determined. The thickness of the top five components with the highest contribution in the two models is used as the final design variables. Design of experiment (DOE) is carried out based on the Latin Hypercube sampling method, and then the surrogate models are fitted by the least squares regression method (LSR) based on the DOE sampling data, and the accuracy of the models are validated by error analysis. With the minimization of the body mass being as the objective and other performance responses as constraints, an optimization problem is formulated for the lightweight design

Yang, Xiujian, Tian, Dekuan, Liu, Jiaqi, Cui, Yan, Lin, Qiang

Validation of Pedestrian Collision Reconstruction Using the PC-Crash Multibody Pedestrian Model

2025-01-8681To be published on 04/01/2025

When evaluating a collision between a vehicle and a pedestrian, a reconstructionist will often attempt to determine the location on the roadway where the first contact occurred, the speed of the vehicle at impact, the speed of the pedestrian at impact, and the motion of the pedestrian from first contact to rest. Computer simulation using a multibody pedestrian model is a method that can assist the reconstructionist to simultaneously determine the location of impact and the vehicle speed. Multibody simulation can also inform the reconstructionist’s determination of the speed of the pedestrian at impact, their body posture, and their motion from first contact to rest. PC-Crash is a collision simulation software that is widely used by the accident reconstruction community. PC-Crash includes a pedestrian multibody model that can be used for collision simulation. This article validates the use of the pedestrian multibody model in PC-Crash for analyzing pedestrian collisions. This model is

Rose, Nathan, Smith, Connor, Carter, Neal, Metanias, Andrew

A Model for the Design of Automated Vehicle Event Data Recorders

2025-01-8678To be published on 04/01/2025

We propose a model for the design of a new generation of event data recorder (EDR) aimed for automated driving systems (ADS) to support crash analysis, risk assessment and accidents reconstruction. Current EDRs, or described in standards and regulations do not address detailed design requirements that are necessary by all SAE 3016 driving automation levels 1 through 5. These standards and regulations include IEEE 1616.1, SAE J1698, U.S. CFR, Title 49 Part 563, FMVSS No 405, UN regulation 160, and others. Traditional onboard EDRs are a devices that capture and store critical vehicle data for several seconds before, during and after any crash where an airbag is triggered or there is an excessive rate of vehicle deceleration. There are efforts to design new kinds of EDRs to capture and store data during and after crashes that involve automated vehicles. IEEE 1616.1 defines requirements and metrics for data storage in a data storage system for automated driving (DSSAD), as well as related

Pimentel, Juan

Improving Modal Frequencies in Class 5 Truck Fuel Cell Tank Structure through Topology Optimization

2025-01-8648To be published on 04/01/2025

In addition to electric vehicles (EVs), hydrogen fuel cell systems are gaining attention as energy-efficient propulsion options. However, designing fuel cell vehicles presents unique challenges, particularly in terms of storage systems for heavy hydrogen tanks. These challenges impact factors such as NVH (noise, vibration, and harshness) and safety performance. This study presents a topology optimization study for Hydrogen Energy Storage System (HESS) tank structure in Class 5 trucks, with a focus on enhancing the modal frequencies. The study considers a specific truck configuration with a HESS structure located behind the crew cab, consisting of two horizontally stacked hydrogen tanks and two tanks attached on both sides of the frame. The optimization process aimed to meet the modal targets of this hydrogen tank structure in the fore-aft (X) and lateral (Y) directions, while considering other loadcases such as a simplified representation of GST (global static torsion), simplified side

Yoo, Dong Yeon, Chavare, Sudeep, Viswanathan, Sankar, Mouyianis, Adam

Literature Review and Framework for Identifying Seat Belt Misuse and Misrouting in Frontal Collisions

2025-01-8721To be published on 04/01/2025

The effect of seat belt misuse and/or misrouting is important to consider because it can influence occupant kinematics, reduce restraint effectiveness, and increase injury risk. One of the objectives of this study was to identify types of lap-shoulder belt misuse/misrouting and associated injury patterns from a literature review. Belt misuse included shoulder belt only, lap belt only, or shoulder belt under the arm, for example, while belt misrouting included lap belt on the abdomen, shoulder belt above the breasts, or shoulder belt on the neck. The literature review also highlighted the lack of information on the prevalence of belt misuse and misrouting, partially due to assessment complexity. The literature review also identified various methods used to assess misuse/misrouting including testimonies and physical evidence on the occupant (i.e., belt marks/ injury pattern) and on the vehicle interior and/or restraint system (i.e., loading marks). The second objective was to develop an

Gu, Emily, parenteau, Chantal

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