Browse Topic: Crashes

Items (6,150)

Accuracy Requirements for the Road Friction Coefficient Estimation of a friction-adaptive Automatic Emergency Braking System as a Software Solution for Integrated Chassis Control

2025-01-0349To be published on 09/15/2025

The number of traffic accidents in longitudinal traffic has been significantly reduced by the series introduction of Automatic Emergency Braking (AEB) systems. Nevertheless, more than a third of these accidents still cannot be prevented because, according to the German Federal Statistical Office (Destatis), they are caused by wet or snow-covered roads. For this reason, current research work is focusing on adapting the functionality of AEB systems to the road condition by an estimated value of the road friction coefficient. This paper uses simulation to determine the accuracy with which the road friction coefficient must be known for a friction-adaptive AEB system to prevent rear-end collisions in statistically relevant Euro NCAP test scenarios, even on wet and snow-covered roads. The friction-adaptive AEB system, which is being developed at IAV GmbH as a customizable software solution for Integrated Chassis Control (ICC), uses the estimated value of the road friction coefficient to

Ahrenhold, Tim, Wielitzka, Mark, Binnewies, Tomas, Henze, Roman

DISRUPT - Decentralized Intelligent System for Road User Prediction and Tracking

2025-01-0294

07/02/2025

We present DISRUPT, a research project to develop a cooperative traffic perception and prediction system based on networked infrastructure and vehicle sensors. Decentralized tracking and prediction algorithms are used to estimate the dynamic state of road users and predict their state in the near future. Compared to centralized approaches, which currently dominate traffic perception, decentralized algorithms offer advantages such as greater flexibility, robustness and scalability. Mobile sensor boxes are used as infrastructure sensors and the locally calculated state estimates are communicated in such a way that they can augment local estimates from other sensor boxes and/or vehicles. In addition, the information is transferred to a cloud that collects the local estimates and provides traffic visualization functionalities. The prediction module then calculates the future dynamic state based on neurocognitive behavior models and a measure of a road user's risk of being involved in

Beutenmüller, Frank, Brostek, Lukas, Doberstein, Christian, Han, Longfei, Kefferpütz, Klaus, Obstbaum, Martin, Pawlowski, Antonia, Rössert, Christian, Sas-Brunschier, Lucas, Schön, Thilo, Sichermann, Jörg

Exploring the Correlation between Physiological States and Driving Behavior on Highways with Integrated ECG Measurements

2025-01-0292

07/02/2025

Human driver errors, such as distracted driving, inattention, and aggressive driving, are the leading causes of road accidents. Understanding the underlying factors that contribute to these behaviors is critical for improving road safety. Previous studies have shown that physiological states, like raised heart rates due to stress and anxiety, can influence driving behavior, leading to erratic driving and an increased risk of accidents. In this study, we conducted on-road tests using a measurement system based on the Driver-Driven vehicle-Driving environment (3D) method. We collected physiological signals, specially electrocardiography (ECG) data, from human drivers to examine the relationship between physiological states and driving behaviors. The aim was to determine whether ECG can serve as an indicator of potential risky driving behaviors, such as sudden acceleration and frequent steering adjustments. This information enables automated driving (AD) systems to intervene in dangerous

Ji, Dejie, Flormann, Maximilian, Bollmann, Julian, Henze, Roman, Deserno, Thomas M.

Early Detection of the Loss of Control of Motorsport Vehicles

10-09-03-0029

06/30/2025

The article investigates how to detect as quickly as possible whether the driver will lose control of a vehicle, after a disturbance has occurred. Typical disturbances refer to wind gusts, obstacle avoidance, a sudden steer, traversing a pothole, a kick by another vehicle, and so on. The driver may be either human or non-human. Focus will be devoted to human drivers, but the extension to automated or autonomous cars is straightforward. Since the dynamic behavior of vehicle and driver is described by a saddle-type limit cycle, a proper theory is developed to use the limit cycle as a reference trajectory to forecast the loss of control. The Floquet theory has been used to compute a scalar index to forecast stable or unstable motion. The scalar index, named degree of stability (DoS), is computed very early, in the best case, in a few milliseconds after the disturbance has ended. Investigations have been performed at a dynamic driving simulator. A 14 DoF vehicle model, virtually driven by

Della Rossa, Fabio, Fontana, Matteo, Giacintucci, Samuele, Gobbi, Massimiliano, Mastinu, Giampiero, Previati, Giorgio

Traumatic Head and Brain Injuries in Helmeted Motorcycle Crashes

2025-22-0006

06/27/2025

This study presents an analysis of 364 motorcycle helmet impact tests, including standard certified full-face, open-face, and half-helmets, as well as non-certified (novelty) helmet designs. Two advanced motorcycle helmet designs that incorporate technologies intended to mitigate the risk of rotational brain injuries (rTBI) were included in this study. Results were compared to 80 unprotected tests using an instrumented 50th percentile Hybrid III head form and neck at impact speeds ranging from 6 to 18 m/s (13 to 40 mph). Results show that, on average, the Head Injury Criterion (HIC) was reduced by 92 percent across certified helmets, compared to the unhelmeted condition, indicating substantial protection against focal head and brain injuries. However, findings indicate that standard motorcycle helmets increase the risk of AIS 2 to 5 rotational brain injuries (rTBI) by an average of 30 percent compared to the unprotected condition, due to the increased rotational inertia generated by

Lloyd, John

Pulse and Polynomial Functions to Predict Vehicle Acceleration Using Event Data Recorder Delta-V in Frontal and Rear-End Collisions

2025-01-5046

06/27/2025

The lack of recorded acceleration and limited Delta-V (ΔV) resolution in many vehicle event data recorders necessitates the development of a method to predict continuous vehicle acceleration based on ΔV responses. This study developed a method of obtaining continuous acceleration by regressing pulse functions (triangular, half-sine, haversine) and polynomial functions (orders 3–6) to a ΔV curve and deriving the corresponding acceleration–time curve. The effectiveness of this method was demonstrated using real-world ΔV response data from front and rear-end collisions. Comparisons were performed between peak and average acceleration values from each front and rear-end crash pulse. Results indicated that a triangular pulse function predicted similar peak acceleration values to the vehicle’s actual acceleration in frontal and rear-end impacts. Average acceleration in frontal impacts was best predicted utilizing a fifth-order polynomial, while a sixth-order polynomial demonstrated the best

Westrom, Clyde, Adanty, Kevin, Shimada, Sean D.

A Dynamic Hydroplaning Study: A Fluid–Structure Interaction Model for Road Vehicle Tire Analysis

15-18-03-0015

06/24/2025

Hydroplaning contributes to approximately 20% of traffic accidents during adverse weather conditions, with factors such as velocity, water film thickness, tire inflation, and vehicle weight playing significant roles. This study aims to simulate the hydroplaning phenomenon using a fluid–structure interaction model based on the coupled Eulerian–Lagrangian (CEL) capabilities of ABAQUS. Results reveal that vehicle linear velocity is a key determinant of hydroplaning risk, with a positive correlation observed. The findings suggest maintaining speeds under 50 km/h to mitigate hydroplaning risk, contingent on well-maintained, properly inflated tires. Multiple linear regression analysis further demonstrates correlations among velocity, tire inflation, quarter vehicle load, and water film thickness in predicting the reaction force between the tire and roadway. The proposed scheme provides a predictive mechanism for hydroplaning risk under varying conditions, offering valuable insights into

Aboelsaoud, Mostafa, Taha, Ahmed Abdelsalam, Abo Elazm, Mohamed, Elgamal, Hassan Anwar

Yaw Motion of Motor Vehicles

2025-01-5043

06/20/2025

Vehicular accident reconstruction is intended to explain the stages of a collision. This also includes the description of the driving trajectories of vehicles. Stored driving data is now often available for accident reconstruction, increasingly including gyroscopic sensor readings. Driving dynamics parameters such as lateral acceleration in various driving situations are already well studied, but angular rates such as those around the yaw axis are little described in the literature. This study attempts to reduce this gap somewhat by evaluating high-frequency measurement data from real, daily driving operations in the field. 813 driving maneuvers, captured by accident data recorders, were analyzed in detail and statistically evaluated. These devices also make it possible to record events without an accident. The key findings show the average yaw rates as a function of driving speed as well as the ratio between mean and associated peak yaw rate. Beyond that, considerably lower yaw rates

Fuerbeth, Uwe

Observers for Laser Safety in the Navigable Airspace

ARP5535B (Current)

06/17/2025

This document applies to safety observers or spotters involved with the use of outdoor laser systems. It may be used in conjunction with AS4970.

G-10T Laser Safety Hazards Committee

Assessment of the Skull Fracture Prediction Capability of Finite Element Head Models

2025-22-0005

06/16/2025

The development of drones has raised questions about their safety in case of high-speed impacts with the head. This has been recently studied with dummies, postmortem human surrogates and numerical models but questions are still open regarding the transfer of skull fracture tolerance and procedures from road safety to drone impacts. This study aimed to assess the performance of an existing head FE model (GHBMC M50-O v6.0) in terms of response and fracture prediction using a wide range of impact conditions from the literature (low and high-speed, rigid and deformable impactors, drones). The fracture prediction capability was assessed using 156 load cases, including 18 high speed tests and 19 tests for which subject specific models were built. The GHBMC model was found to overpredict peak forces, especially for rigid impactors and fracture cases. However, the model captured the head accelerations tendencies for drone impacts. The formulation of bone elements, the failure representation

Pozzi, Clément, Gardegaront, Marc, Allegre, Lucille, Beillas, Philippe

Head Accelerations and Concussion Risks in Low-to-Moderate–Speed Rear-End Collisions

2025-01-5041

06/10/2025

Recent studies have investigated head injury metrics, including mild traumatic brain injury (mTBI), or concussion risks, in low- to moderate-speed rear-end collisions, with linear and angular head accelerations contributing to the risk of developing a concussion. The present study analyzes head acceleration values in rear-end collisions at an impact severity of 5–30 km/h delta-V. Biomechanical data was obtained from HIII 50th percentile male anthropomorphic test devices (ATDs) seated in the target subject vehicles and utilizing safety restraints and head rests. Concussion risks were calculated from resultant linear and angular head accelerations recorded in the ATDs, and a linear regression model was used to determine what, if any, relationship existed between these head injury metrics and impact severity. The results indicate that there is a significant and positive relationship between head acceleration metrics and impact severity, particularly in the sagittal plane, with F-values

Garcia, Beatriz, Emanet, Hatice Seyda, Hoffman, Austin

Investigation of Injury Risk Functions of THOR-AV 50th Percentile Male Dummy

2025-22-0004

06/05/2025

This research investigated injury risk functions (IRF) for the THOR-AV 50th percentile male dummy in accordance with ISO TS18506, focusing on areas with design changes. The IRF development utilized a combination of physical tests and finite element (FE) model simulations. For certain postmortem human subject test cases lacking physical dummy tests, the validated Humanetics THOR-AV FE model (v0.7.2) was used to quickly generate data, with the understanding that final IRFs based on full physical test data might offer greater accuracy. Log-logistic, log-normal, and Weibull survival functions were fitted with 95% confidence intervals. The Akaike Information Criterion, Goodman-Kruskal-Gamma, Area under the Curve of Receiver Operating Characteristic, and Quantile-Quantile plot were employed to assess the prediction strength and relative quality of the final IRF selections. Among the three survival distributions, the Weibull distribution provided the best fit. The lumbar Fz was identified as

Wang, Z. Jerry, Hu, George

Analysis and Evaluation of Roll Safety Thresholds of Tractor Semi-Trailer Vehicles during Turning Maneuvers Based on the Yaw Rate of Vehicle Bodies and Roll Safety Factor

02-18-04-0024

06/05/2025

This article aims to analyze and evaluate the roll safety thresholds (RSTs) and roll safety zones of tractor semi-trailer vehicles during turning maneuvers, using the roll safety factor (RSF) and yaw rate of the vehicle bodies. To achieve this, a full dynamics model is established using the multibody system method. This model is then used to survey and evaluate the vehicle’s motion state, using ramp steer maneuver (RSM) steering rules. In each survey case, the maximum values of RSF and yaw rate of vehicle bodies are synthesized in 3D data, with an initial velocity range of 40 km/h to 80 km/h and a magnitude of steering wheel angle range of 12.5° to 300°. These 3D data are used to determine the proposed values of RSF, which can be used as examples to set the threshold values of the yaw rate of vehicle bodies and roll safety zones. At a velocity of 60 km/h, the dynamic rollover threshold for proposed roll safety factor (RSFprop) is equal to 1, with corresponding values of 15.718°/s and

Hung, Ta Tuan

LightNetDehaze: Lightweight and Unsupervised Single-Image Dense Haze Removal

12-09-01-0005

05/26/2025

Image dehazing techniques can play a vital role in object detection, surveillance, and accident prevention, especially in scenarios where visibility is compromised because of light scattering by atmospheric particles. To obtain a high-quality image or as an initial step in processing, it’s crucial to restore the scene’s information from a single image, given that this is an ill-posed inverse problem. The present approach utilized an unsupervised learning approach to predict the transmission map from a hazy image and used YOLOv8n to detect the car from a clear recovered image. The dehazing model utilized a lightweight parallel channel architecture to extract features from the input image and estimate the transmission map. The clear image is recovered using an atmospheric scattering model and given to the YOLOv8n for car detection. By incorporating dark channel prior loss during training, the model eliminates the need for a paired dataset. The proposed dehazing model with fewer

Dave, Chintan, Patel, Hetal, Kumar, Ahlad

Occupant Restraint and Equipment Mounting Integrity - Rear Impact Ambulance Patient Compartment

J3044_202505 (Current)

05/20/2025

This SAE Recommended Practice describes the test procedures for conducting rear impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mount testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.

Truck Crashworthiness Committee

Occupant Restraint and Equipment Mounting Integrity - Side Impact Ambulance Patient Compartment

J2956_202505 (Current)

05/20/2025

This SAE Recommended Practice describes the test procedures for conducting side impact occupant restraint and equipment mounting integrity tests for ambulance patient compartment applications. Its purpose is to describe crash pulse characteristics and establish recommended test procedures that will standardize restraint system and equipment mounting testing for ambulances. Descriptions of the test set-up, test instrumentation, photographic/video coverage, and the test fixtures are included.

Truck Crashworthiness Committee

Proposed Reformulation of Brain Injury Criteria (BrIC) Using Head Rotation-Induced Brain Injury Thresholds Simulated and Derived Directly from A Subhuman Primate Finite Element Model

2025-22-0003

05/13/2025

Recent studies have found that Brain Injury Criteria (BrIC) grossly overpredicts instances of real-world, severe traumatic brain injury (TBI). However, as it stands, BrIC is the leading candidate for a rotational head kinematics-based brain injury criteria for use in automotive regulation and general safety standards. This study attempts to understand why BrIC overpredicts the likelihood of brain injury by presenting a comprehensive analysis of live primate head impact experiments conducted by Stalnaker et al. (1977) and the University of Pennsylvania before applying these injurious conditions to a finite element (FE) monkey model. Data collection included a thorough analysis and digitization of the head impact dynamics and resulting pathology reports from Stalnaker et al. (1977) as well as a representative reconstruction of the Penn II baboon diffuse axonal injury (DAI) model. Computational modeling techniques were employed on a FE Rhesus monkey model, first introduced by Arora et al

Demma, Dominic R., Tao, Ying, Zhang, Liying, Prasad, Priya

Development of a Generic Nearside Impact Test Fixture for Evaluating In-Vehicle Crashworthiness of Wheelchairs

2025-22-0002

05/13/2025

Current voluntary standards for wheelchair crashworthiness only test under frontal and rear impact conditions. To help provide an equitable level of safety for occupants seated in wheelchairs under side impact, we developed a sled test procedure simulating nearside impact loading using a fixed staggered loading wall. Publicly available side impact crash data from vehicles that could be modified for wheelchair use were analyzed to specify a relevant crash pulse. Finite element modeling was used to approximate the side impact loading of a wheelchair during an FMVSS No. 214 due to vehicle intrusion. Validation sled tests were conducted using commercial manual and power wheelchairs and a surrogate wheelchair base fixture. Test procedures include methods to position the wheelchair to provide consistent loading for wheelchairs of different dimensions. The fixture and procedures can be used to evaluate the integrity of wheelchairs under side impact loading conditions.

Boyle, Kyle, Hu, Jingwen, Manary, Miriam, Orton, Nichole R., Klinich, Kathleen D.

Crash Performance Improvement: The Impact of Engine Mount Crash Plates on Achieving a 5-Star Safety Rating

2025-01-0085

05/05/2025

Electric vehicles (EVs) differ from internal combustion engine (ICE) vehicles in that they lack a conventional engine and feature an electric drive unit, leading to distinct dynamic behaviours in the powertrain. Additionally, the arrangement of auxiliary components in EVs often differs from that in traditional ICE vehicles, which can sometimes significantly impact safety ratings. This paper examines a case study of a critical failure during a crash test, where displacement of an engine mount arm caused substantial structural intrusion and reduced the vehicle’s safety rating. To address this issue and enhance crashworthiness, a “crash plate” was designed and integrated into the mount system. This solution effectively constrained the mount arm’s movement during impact, preventing the intrusion observed in previous tests. The paper provides a detailed analysis of the crash plate’s dimensions and its relationship to the engine mount, demonstrating its potential for broader application in

Hazra, Sandip, Khan, Arkadip, Mohare, Gourishkumar

Analysis of Lane Departure Caused by Inadequate Motorcycle Driving Maneuvers Due to Road Alignment

2024-32-0034

04/18/2025

There are many riders who drive motorcycles on winding mountain roads and caused single motorcycle traffic accidents on curved roads by lane departure. Driving a motorcycle requires subtle balancing and maneuvering. In this study, in order to clarify the influence of lane departure caused by inadequate driving maneuvers against road alignment, the authors analyzed the required curve initial operation and driving maneuvers in curves depending on the traveling speed using a kinematics simulation for motorcycle dynamics. In addition, it was analyzed how inadequate driving maneuvers for curved roads can easily cause lane departure. As a result, it shows that the steering maneuvers and the lean of motorcycle body during the curves are highly affected by the vehicle speed, and the required maneuvers increases rapidly with increasing speed. The inadequate maneuver in the curves, especially for the lean of motorcycle body and steering torque, even by 10%, may cause failure to follow the

Kuniyuki, Hiroshi, Takechi, So

Predicting Real-time Crash Risks during Hurricane Evacuation Using Connected Vehicle Data

09-13-01-0006

04/12/2025

Hurricane evacuations generate high traffic demand with increased crash risk. To mitigate such risk, transportation agencies can adopt high-resolution vehicle data to predict real-time crash risks. Previous crash risk prediction models mainly used limited infrastructure sensor data without covering many road segments. In this article, we present methods to determine potential crash risks during hurricane evacuation from an emerging alternative data source known as connected vehicle data that contain vehicle speed and acceleration information collected at a high frequency (mean = 14.32, standard deviation = 6.82 s). The dataset was extracted from a database of connected vehicle data for the evacuation period of Hurricane Ida on Interstate-10 in Louisiana. Five machine learning models were trained considering weather features and different traffic characteristics extracted from the connected vehicle data. The results indicate that the Gaussian process boosting and extreme gradient

Syed, Zaheen E Muktadi, Hasan, Samiul

A Low-Entry Bus Body Structure Performance under the Conditions of the New Car Assessment Program Frontal Crash Tests

09-13-02-0007

04/09/2025

The New Car Assessment Program (e.g., US NCAP and EuroNCAP) frontal crash tests are an essential part of vehicle safety evaluations, which are mandatory for the certification of civil means of transport prior to normal road exploitation. The presented research is focused on the behavior of a tubular low-entry bus frame during a frontal impact test at speeds of 32 and 56 km/h, perpendicular to a rigid wall surface. The deformation zones in the bus front and roof parts were estimated using Ansys LS-DYNA and considered such factors as the additional mass (1630 kg) of electric batteries following the replacement of a diesel engine with an electric one. This caused stabilization of the electric bus body along the transverse axis, with deviations decreased by 19.9%. Speed drop from 56 to 32 km/h showed a reduction of the front window sill deformations from 172 to 132 mm, and provided a twofold margin (159.4 m/s2) according to the 30g ThAC criterion of R80. This leads to the conclusion about

Holenko, Kostyantyn, Dykha, Aleksandr, Koda, Eugeniusz, Kernytskyy, Ivan, Royko, Yuriy, Horbay, Orest, Berezovetska, Oksana, Rys, Vasyl, Humeniuk, Ruslan, Berezovetskyi, Serhii, Chalecki, Marek

Solving Vehicle Speed and Acceleration from Video Evidence Using Optimization

2025-01-8683

04/01/2025

This paper introduces a method to solve the instantaneous speed and acceleration of a vehicle from one or more sources of video evidence by using optimization to determine the best fit speed profile that tracks the measured path of a vehicle through a scene. Mathematical optimization is the process of seeking the variables that drive an objective function to some optimal value, usually a minimum, subject to constraints on the variables. In the video analysis problem, the analyst is seeking a speed profile that tracks measured vehicle positions over time. Measured positions and observations in the video constrain the vehicle’s motion and can be used to determine the vehicle’s instantaneous speed and acceleration. The variables are the vehicle’s initial speed and an unknown number of periods of approximately constant acceleration. Optimization can be used to determine the speed profile that minimizes the total error between the vehicle’s calculated distance traveled at each measured

Snyder, Sean, Callahan, Michael, Wilhelm, Christopher, Johnk, Chris, Lowi, Alvin, Bretting, Gerald

High-Speed FCW & AEB Testing of Tesla Model 3's Across Software Updates

2025-01-8695

04/01/2025

A total of 148 tests were conducted to evaluate the Forward Collision Warning (FCW) and Automatic Emergency Braking (AEB) systems in five different Tesla Model 3 vehicles between model years 2018 and 2020 across four calendar years. These tests involved stationary vehicle targets, including a foam Stationary Vehicle Target (SVT), a Deformable Stationary Vehicle Target (DSVT), a live vehicle with brake lights, and a SoftCar360 designed for high-speed impact tests. The evaluations were conducted at speeds of 35, 50, 60, 65, 70, 75, and 80 miles per hour (mph) during both daytime and nighttime conditions and utilized early and medium FCW settings. These settings, part of Tesla's Collision Avoidance AssistTM, modify object detection alerts and the timing of visual and auditory warnings issued to drivers. The 2018 to 2020 vehicles initially utilized cameras, radar and ultrasonic sensors (USS) for object detection. Tesla updated their Autoilot software and detection algorithms to a vision

Harrington, Shawn, Nagarajan, Sundar Raman

Bicycle Pitch-over Reconstruction Analysis

2025-01-8684

04/01/2025

During a pitch-over event, the forward momentum of the combined bicycle and rider is suddenly arrested causing the rider and bicycle to rotate about the front wheel and also possibly propelling the rider forward. This paper examines the pitch-over of a bicycle and rider using two methods different from previous approaches. 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 simulations to evaluate the kinematics and kinetics of the bicycle and rider interacting with front wheel obstructions of different heights. The effect of variables such as rider weight, rider coupling to the bicycle, bicycle speed, and obstruction height on resulting kinematics were evaluated. The analysis shows that a larger

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

A Training Method for Multiagent Systems Promises Safe Operation

TBMG-52805

04/01/2025

Drone show accidents highlight the challenges of maintaining safety in what engineers call “multiagent systems” — systems of multiple coordinated, collaborative, and computer-programmed agents, such as robots, drones, and self-driving cars.

New Implant May Help Patients Regenerate Their Own Heart Valves

TBMG-52862

04/01/2025

Every year, more than 5 million people in the United States are diagnosed with heart valve disease, but this condition has no effective long-term treatment. When a person’s heart valve is severely damaged by a birth defect, lifestyle, or aging, blood flow is disrupted. If left untreated, there can be fatal complications.

An Overview and Testing of Pedal Misapplication Systems

2025-01-870504/01/2025

Performance testing was conducted to assess the effectiveness of five different pedal misapplication mitigation (PMM) systems in a simulated PMM scenario. These systems are components of advanced driver-assistance systems (ADAS), which are designed to detect and mitigate inadvertent sudden accelerator pedal misapplications by drivers. A 2023 BMW iX, 2020 Tesla Model 3, 2014 Subaru Forester, 2020 Subaru Outback, and a 2023 Subaru Ascent were tested in a simulated pedal misapplication scenario, whereby the test vehicle's accelerator was quickly depressed with a stationary pedestrian and vehicle target in front of the test vehicle. The testing involved measuring the performance of the respective vehicles' pedal misapplication mitigation systems, including when or if engine/motor output or throttle was limited or reduced, whether a forward collision warning was provided, or if the vehicle automatically engaged braking and/or braked to a stop before contact with the soft targets. Results of

Harrington, Shawn, Takbhate, Shubham Ramraja, Martin, Nicholas, Patrick-Moline, Peyton, Handzic, Dino

Quantifying the Uncertainty in Bicycle-Computer Speed Measurements

2025-01-8701

04/01/2025

Bicycle computers record and store kinematic and physiologic data that can be useful for forensic investigations of crashes. The utility of speed data from bicycle computers depends on the accurate synchronization of the speed data with either the recorded time or position, and the accuracy of the reported speed. The primary goals of this study were to quantify the temporal asynchrony and the error amplitudes in speed measurements recorded by a common bicycle computer over a wide area and over a long period. We acquired 96 hours of data at 1-second intervals simultaneously from three Garmin Edge 530 computers mounted to the same bicycle during road cycling in rural and urban environments. Each computer recorded speed data using a different method: two units were paired to two different external speed sensors and a third unit was not paired to any remote sensors and calculated its speed based on GPS data. We synchronized the units based on the speed signals and used one of the paired

Booth, Gabrielle R., Siegmund, Gunter P.

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

2025-01-8207

04/01/2025

Road safety and traffic management face significant challenges due to secondary crashes, which frequently cause increased traffic, delays, and collisions. Traditional methods for anticipating secondary crashes often overlook the importance of different road types, resulting in suboptimal predictions and response plans. This research presents a novel method that combines a hybrid machine-learning model with a functional class-based weighting strategy to classify secondary crashes. The functional classes in the dataset are categorized 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 reflecting its proportional importance in the likelihood of a subsequent crash, based on historical data and road usage patterns. This weighting technique is integrated into a hybrid model architecture that trains a Random Forest (RF) model on structured data to

Patil, Mayur, Marik PE, Stephanie

Advanced Driver Assistance Systems (ADAS): Assessing the Efficacy of Non-Impact Testing for Evaluating the Performance of Frontal Collision Mitigation Technology

2025-01-8056

04/01/2025

As Automatic Emergency Braking (AEB) systems become standard equipment in more light duty vehicles, the ability to evaluate these systems efficiently is becoming critical to regulatory agencies and manufacturers. A key driver of the practicality of evaluating these systems’ performance is the potential collision between the subject vehicle and test target. AEB performance can depend on vehicle-to-vehicle closing speeds, crash scenarios, and nuanced differences between various situational and environmental factors. Consequently, high speed impacts that may occur while evaluating the performance of an AEB system, as a result of partial or incomplete mitigation by an AEB activation, can cause significant damage to both the test vehicle and equipment, which may be impractical. For tests in which impact with the test target is not acceptable, or as a means of increasing test count, an alternative test termination methodology may be used. One such method constitutes the application of a late

Kuykendal, Michelle, Easter, Casey, Koszegi, Giacomo, Alexander, Ross, Paradiso, Marc, Scally, Sean

Evaluation of Several Tesla Dashcam Angles for Model 3 and Y via Reverse Project Photogrammetry

2025-01-8700

04/01/2025

Tesla Model 3 and Model Y vehicles come equipped with a standard dashcam feature with the ability to record video in multiple directions. Front, side, and rear views were readily available via direct USB download. Additional types of front and side views were indirectly available via privacy requests with Tesla. Prior research neither fully explored the four most readily available camera views across multiple vehicles nor field camera calibration techniques particularly useful for future software and hardware changes. Moving GPS instrumented vehicles were captured traveling approximately 7.2 kph to 20.4 kph across the front, side, and rear views available via direct USB download. Reverse project photogrammetry projects and video timing data successfully measured vehicle speeds with an average error of 2.45% across 25 tests. Previously researched front and rear camera calibration parameters were reaffirmed despite software changes, and additional parameters for the side cameras

Jorgensen, Michael, Swinford, Scott, Imada, Kevin, Farhat, Ali

Assessment of Injuries in Rear Impacts

2025-01-8727

04/01/2025

Rear impacts make up a significant portion of crashes in the United States. To date, regulations on rear impacts have focused on fuel system integrity and seat performance, while most research has focused on seat performance in relation to occupants’ injuries, with some analyses of crash severity and seat belt effects. The performance of seats and seat belts may vary depending on the size of the occupant. Understanding how occupant characteristics, as well as crash scenarios, affect injury outcomes can show opportunities for further enhancements in rear impact occupant protection. This paper presents analyses using survey weighted logistic regression models to understand the factors affecting serious injury outcomes (i.e., MAIS 3+) in rear impacts, exploring the potential for improving occupant outcomes. Three separate models are evaluated, focusing on 1) overall injury level, 2) head, neck, and cervical-spine injuries, and 3) thorax, abdomen, thoracic- and lumbar-spine injuries for

Greib, Joshua, Jurkiw, Renee, Kryzaniwskyj, Tanja, Owen, Susan, Van Rooyen, Paul, Whelan, Stacey, Williamson, John

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

2025-01-8648

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 load cases such as a simplified representation of GST (global static torsion), simplified

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

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

2025-01-8218

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

CL-infoRRT Collision-Avoidance Trajectory Planning for Autonomous Vehicle

2025-01-8027

04/01/2025

To ensure the safety and stability of road traffic, autonomous vehicles must proactively avoid collisions with traffic participants when driving on public roads. Collision avoidance refers to the process by which autonomous vehicles detect and avoid static and dynamic obstacles on the road, ensuring safe navigation in complex traffic environments. To achieve effective obstacle avoidance, this paper proposes a CL-infoRRT planning algorithm. CL-infoRRT consists of two parts. The first part is the informed RRT algorithm for structured roads, which is used to plan the reference path for obstacle avoidance. The second part is a closed-loop simulation module that incorporates vehicle kinematics to smooth the planned obstacle avoidance reference path, resulting in an executable obstacle avoidance trajectory. To verify the effectiveness of the proposed method, four static obstacle test scenarios and four RRT comparison algorithms were designed. The implementation results show that all five

Wu, Wei, Lu, Jun, Zeng, Dequan, Yang, Jinwen, Hu, Yiming, Yu, Qin, Wang, Xiaoliang

A Preliminary Study of Occupant Kinematics and Injuries in a Frontal Crash with Occupant Face-to-Face Scenario

2025-01-8736

04/01/2025

This paper investigates a novel seating arrangement where occupants face each other, focusing on occupant safety during a 56 km/h frontal impact, a standard test condition for assessing crashworthiness. A preliminary study was carried out, examining three distinct cases: a forward-facing 50th percentile occupant in third row seat, a rear-facing 50th percentile occupant in second row seat, and the interaction between these two occupant orientations. The study utilized both elastic flexible and rigid seat designs to analyze the impact on occupant kinematics and injury outcomes. The results demonstrate that the seating position has a significant influence on occupant injuries. Rear-facing occupants are primarily at risk due to seat design, whereas forward-facing occupants face a higher risk of injury from the increased space between occupants, lacking a reactive surface to mitigate impact forces. Notably, direct interaction between occupants did not result in severe injuries. However

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

Tube-MPC Based Path Tracking for I Vehicle Considering Data-Driven Stable Region and External Disturbances

2025-01-8262

04/01/2025

Path tracking is a key function of intelligent vehicles, which is the basis for the development and realization of advanced autonomous driving. However, the imprecision of the control model and external disturbances such as wind and sudden road conditions will affect the path tracking effect and even lead to accidents. This paper proposes an intelligent vehicle path tracking strategy based on Tube-MPC and data-driven stable region to enhance vehicle stability and path tracking performance in the presence of external interference. Using BP-NN combined with the state-of-the-art energy valley optimization algorithm, the five eigenvalues of the stable region of the vehicle β−β̇ phase plane are obtained, which are used as constraints for the Tube-MPC controller and converted into quadratic forms for easy calculation. In the calculation of Tube invariant sets, reachable sets are used instead of robust positive invariant sets to reduce the calculation. Simulation results demonstrates that the

Zhang, Haosen, Li, Yihang, Wu, Guangqiang

Lightweight Optimization of an Electric Bus Body Frame Based on the C ² oDE Algorithm

2025-01-8654

04/01/2025

In this work, design optimization for the lightweight of the body frame of a commercial electric bus with the requirements of stiffness, strength and crashworthiness is presented. The technique for order preference by similarity to ideal solution (TOPSIS) is applied to calculate the components that have a great impact on the output response of the static modal model and the rear-end collision model. The thickness of the five components with the highest contribution in the two models is determined as the final design variable. 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 (LSR) method based on the DOE sampling data. The error analysis of the surrogate model is carried out to determine whether it can replace the finite element (FE) model for optimization, then the optimization scheme for lightweight optimization of electric bus frame is implemented based on the algorithm of

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

Predicting Head Injury Criterion in Real-World Frontal Impacts

2025-01-8709

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 rectangular, triangular, polynomial, half-sine, and haversine 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 these 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 included driver occupants. Head acceleration and shoulder belt load channels of Hybrid III 50th percentile male anthropomorphic test devices were collected and separated for training a set of ratios and testing their performance. Rectangular, triangular, quadratic, half-sine, and haversine pulse functions

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

Decelerations for Vehicles with Anti-Lock Brake Systems (ABS) during Wet-to-Dry Transitions on Asphalt and Concrete Road Surfaces

2025-01-8703

04/01/2025

The braking performance of newer anti-lock braking system (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 and

Miller, Ian, King, David, Siegmund, Gunter

The Accuracy of Vehicle Speeds, Decelerations, and Brake Onset Times Calculated from Onboard Dash Cameras

2025-01-8691

04/01/2025

Videos from cameras onboard a moving vehicle are increasingly available to collision reconstructionists. The goal of this study was to evaluate the accuracy of speeds, decelerations, and brake onset times calculated from onboard dash cameras (“dashcams”) using a match-moving technique. We equipped a single test vehicle with 5 commercially available dashcams, a 5th wheel, and a brake pedal switch to synchronize the cameras and 5th wheel. The 5th wheel data served as the reference for the vehicle kinematics. We conducted 9 tests involving a constant-speed approach (mean ± standard deviation = 57.6 ± 2.0 km/h) followed by hard braking (0.989 g ± 0.021 g). For each camera and brake test, we extracted the video and calculated the camera’s position in each frame using SynthEyes, a 3D motion tracking and video analysis program. Scale and location for the analyses were based on a 3D laser scan of the test site. From each camera’s position data, we calculated its speed before braking and its

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

Daytime and Nighttime Performance Evaluations of the Automatic Emergency Braking and Forward Collision Warning Systems on a 2020 and 2022 Kia Telluride

2025-01-8699

04/01/2025

Testing was conducted in daytime and nighttime conditions to evaluate the performance of the Automatic Emergency Braking and Forward Collision Warning systems present on both a 2020 and 2022 Kia Telluride. The 2022 Kia Telluride was tested during the day at speeds between 35 and 70 miles per hour, while the 2020 Kia Telluride was tested both during the day and at night at speeds between 35 and 60 miles per hour (mph). The daytime testing of both the 2020 and 2022 Kia Telluride utilized a foam stationary vehicle target. The nighttime testing of the 2020 Kia Telluride utilized a live 2006 Chevrolet Tahoe as the target with the brake lights on. Testing measured the Time to Collision (TTC) values of the visual/audible component of the Forward Collision Warning (FCW) that was presented to the driver. Further, testing also quantified the timing and magnitude of the two-phase response of the Automatic Emergency Braking (AEB) system. The results of both sets of testing add higher speed FCW and

Harrington, Shawn, Patrick-Moline, Peyton, Nagarajan, Sundar Raman

Deceleration Testing on Various Driving Surfaces for Off-Road Vehicle Operation

2025-01-8704

04/01/2025

Recreational Off-Highway Vehicles (ROVs) also referred to as “side-by-side” vehicles are involved in accidents / crashes due to driver error. This can often be attributed to an operator’s inexperience and failure to differentiate vehicle handling characteristics from that of a traditional automobile. Decelerating testing of ROVs on various surfaces has not been published for these types of vehicles. This work presents test data for use in accident reconstruction and examines the dynamic performance of two exemplar ROVs on various driving surfaces including asphalt, packed dirt, loose gravel and loose, deep sand. Exemplar vehicles, specifically a 4-person “pure-sport” ROV and a single bench utility ROV, are used to gather practical deceleration performance data. Deceleration data comparing tests with fully-locked brakes to tests where the operator manually modulates the brakes to achieve maximum deceleration without brake lockup are also included. The data presented herein is

Swensen, Grant, Warner, Wyatt, Warner, Mark

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

2025-01-8708

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 to develop a simple linear model. The linear regressions

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

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

2025-01-8713

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 image records. Because the TSS data resides in multiple Electronic Control Units (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

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

2025-01-8721

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. As new seatbelt technologies are introduced, it is important to understand the prevalence of seatbelt misuse. This type of information is scarce due to limitations in available field data coding, such as in NASS-CDS and FARS. One explanation may be partially due to assessment complexity in identifying misuse and/or misrouting. An objective of this study was to first identify types of lap-shoulder belt misuse/misrouting and associated injury patterns from a literature review. Nine belt misuse/misrouting scenarios were identified including 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. Next, the literature review identified various methods used to assess misuse

Gu, Emily, Parenteau, Chantal

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

2025-01-8735

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, Yongchen, Hao, Haizhou

Analyzing EV Battery Package Responses during Side Pole Impacts with Multiple Speeds and Locations

2025-01-8730

04/01/2025

Electric vehicles (EVs) have experienced significant growth, and the battery safety of EVs has drawn increased attention. However, the mechanical responses of battery during crashes have rarely been studied. Hence, the objective of this study was to understand EV battery package mechanics during side-pole crashes at different impact locations and speeds beyond regulated side-pole test with one specific speed and one location. An EV finite element (FE) model with a battery package was used. Side-pole impact simulations were conducted at four impact locations, including the baseline impact location according to side-pole impact regulation, plus three positions by moving the rigid pole 400 mm toward the back of the EV and moving the pole 400 and 800 mm toward the front of the EV. In addition, the impact velocities at 32, 50, and 80 km/h were simulated. Based on simulations, the peak relative displacement, the maximum change in gap between batteries, the maximum change in gap between the

Chen, Jian, Bian, Kewei, Mao, Haojie

A Study on Affections of Different Skull-Brain Interface Modeling Approaches on Intracranial Responses in Finite Element Analysis

2025-01-8733

04/01/2025

The skull-brain interface is structurally complex, and various simplification methods have been employed in existing head models to simulate the interaction between the skull and the brain. The modeling approach of the skull-brain interface determines how loads are transmitted to the interior, which is critical for accurately simulating head injuries. Thus, understanding the impact of current skull-brain interface modeling approaches on intracranial simulation results is significant. This study aims to explore the influence of different skull-brain interface modeling methods on the results of finite element models during the development of Advanced Chinese Human Body Models (AC-HUMs) based on the LS-DYNA solver. By comparing the responses of rigidly bonded connections (tied Contact), failure-allowing bonded contacts (tiebreak Contact), shared nodes, and arbitrary Lagrangian-Eulerian (ALE) methods under the Nahum 37 test load conditions, the study analyzes the effects of different

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

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