Publications

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

Vega, H., Cornetto, A., Ngo, L., Hatab, Z., et al.

SAE Technical Paper

The purpose of this study was to outline, test, and confirm the source of the speed-dependent frequency and to develop a validated method for use in forensic applications. A modified version of the passenger vehicle tire equation from prior research was developed to account for the difference in construction associated with commercial vehicle tires, which takes into account only the outer or inner treadblocks whereas the passenger vehicle equation took both into account. Data collection included a commercially available dash camera, a GoPro camera, and a pair of remote microphones to identify the source of the speed-dependent frequency.

• Audio analysis
• Accident reconstruction

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

Vega, H., Ngo, L., Hatab, Z., Cornetto, A., et al.

SAE Technical Paper

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. The reliability of the audio data was compared against speed data collected from a baseline. The post-processing was conducted using iZotope RX to identify the frequencies of interest that were used to compute the vehicle speed and were compared with the ground speed baseline.

• Audio analysis
• Accident reconstruction

Speed Determination Using Audio Analysis of Dash Camera Video for Vehicle Accident Reconstruction

Vega, H., Ngo, J., Engleman, K., Suway, J.

SAE Technical Paper

The purpose of this study was to outline and test the validity of a method for using the audio portion of dash camera video to determine vehicle speed. The reliability of the audio data were then tested against the video and speed data collected for a baseline. The proposed method can be useful to accident reconstructionists in that it provides an additional method for their analysis of vehicle speeds.

• Audio analysis
• Accident reconstruction

Validation of the Arnold Render for Creation of Physically Correct Lighting Models

Vega, H., Suway, J.

SAE Technical Paper

The process presented in this paper utilizes the Arnold render engine within 3DS-Max to analyze the lighting models. Arnold is a physically-based render (PBR) engine and can be used to recreate an accident scene geometry and lighting conditions. In this paper, we compare and validate the relationship between intensity units in Arnold and photometric quantities and illustrate that the lighting produced is based on the physics of light.

• Visibility and lighting

Evaluation of Tesla Dashcam Video System for Speed Determination Via Reverse Projection Photogrammetry

Molnar, B., Peck, L.

SAE Technical Paper

Recent Tesla models contain four integrated onboard cameras that serve the Autopilot and Self-Driving Capabilities of the vehicle and act as a dashcam by recording footage to a local USB drive. The purpose of this study is to analyze the footage recorded by the integrated cameras and determine its suitability for speed determinations of both the host vehicle and surrounding vehicles through photogrammetry analyses. The mean difference between photogrammetry and GPS instrumentation ranged between 0.38 and 0.72 mph across all tests.

• Photogrammetry and mapping
• Accident reconstruction

Analysis of Roadway and Tire Evidence Resulting from Aggressive Braking Maneuvers with ABS-Equipped Motorcycles

Peck, L., Rubio, E., Doria, A., Husher, S., et al.

SAE Technical Paper

With ABS-equipped motorcycles becoming more pervasive, it is critical for collision reconstructionists to have a firm understanding of what evidence may be generated during aggressive braking events performed with these braking systems. Thirty-one instrumented braking tests were performed across three different surfaces using three current ABS-equipped motorcycles to study the residual visible roadway and tire evidence resulting from front-only, rear-only, and maximum effort braking maneuvers.

• Motorcycle
• Testing and instrumentation

A Novel Method for Using RealityCapture in a Forensic Setting

Vega, H., Suway, J., Engleman, K.

SAE Technical Paper

The purpose of this study was to define a procedure using RealityCapture to combine the laser scanner’s ability to capture vertical details that sUASs less effectively observe with the color and roadway details of sUAS imagery not otherwise incorporated by laser scans. It was found that processing sUAS images with RealityCapture in conjunction with laser scans maximized the best attributes offered by both technologies, providing a high-quality and accurate three-dimensional mesh.

• Photogrammetry and mapping

Positional Accuracy of Portable GPS Devices during Different Ride Conditions

Engleman, K., Vega, H., Suway, J., et al.

SAE Technical Paper

The purpose of this study was to explore the positional accuracy of five GPS units for a micromobile vehicle during three different ride conditions: acceleration, deceleration, and constant speed. Location data from the portable GPS devices were compared to reference data obtained from photogrammetry methods based on video recorded by DJI Mavic 2 drones. It was found that the overall average positional deviation from baseline across the devices and three ride conditions was 6.68 ft.

• EDR and telematics
• Testing and instrumentation

A More Robust Method for Digital Video Camera Calibration for Luminance Estimation

Suway, J., Suway, S.

SAE Technical Paper

In this paper, the authors update this methodology for calculating luminance from a digital camera. The updated calibration method results in more accurate luminance estimation over the entire range of the camera’s sensor, particularly in low-light conditions. Further refinements to the fitting methodology result in a robust calibration even in the presence of measurement noise. The methodology allows for the user to mount a camera near the driver’s eye location and to drive through a scene capturing video or still images, which are then analyzed to create a luminance map.

• Visibility and lighting

Systematic Degradation of Retroreflective Materials for Testing and Research

Dinakar, S., Suway, J., Muttart, J., et al.

SAE Technical Paper

In an effort to control the coefficient of retroreflection, a methodology that uniformly obscured parts of the retroreflective materials was developed. Validation testing was conducted using glass bead sheeting as well as microscopic prismatic sheeting. The results showed that, by uniformly obscuring parts of the tape, the coefficient of retroreflection is approximately a linear function of the area exposed to the viewer. This process is useful in simulating degraded retroreflective tape for testing.

• Visibility and lighting
• Testing and instrumentation

Bicycle GPS Positional Accuracy

Desai, E., Wang, P., Suway, J., Engleman, K.

SAE Technical Paper

The purpose of this study is to examine the positional accuracy of several GPS units in real-world environments, including rural landscape and dense urban settings. The location data from portable GPS devices were compared to reference data recorded by a Racelogic VBox 3i with Real Time Kinematic. The GPS systems tested had a positional accuracy that ranged between 5.76 and 13.66 ft when compared to the VBox 3i with RTK.

• EDR and telematics
• Testing and instrumentation

Driver Response Times to Side Road Path Intrusions from SHRP-2 Naturalistic Database

Dinakar, S., Muttart, J., Suway, J., et al.

Proceedings of the Human Factors and Ergonomics Society

In this study, 169 crash and near crash events from the SHRP2 dataset were analyzed. The response behavior of drivers was measured in events where the through drivers’ path was intruded upon by another vehicle perpendicular to its path. Overall, drivers responded significantly faster when the other vehicle failed to stop, and at intersection locations.

• Human factors

Simulation of Retroreflective Materials in a Physically Based Rendering (PBR) Engine

Cornetto, A., Suway, J.

SAE Technical Paper

In this paper we will discuss the engineering and physics of retroreflective materials and how light interacts with these materials. We will also describe how to incorporate the engineering and science of retroreflective materials into a PBR engine to create a fair and accurate light simulation displaying the visibility of the retroreflective materials.

• Visibility and lighting

Quantifying Retroreflective Materials Using Digital Imagery

Suway, J., Cornetto, A.

SAE Technical Paper

Often the material in question cannot be taken to a laboratory for testing and commercially available portable retroreflectometers are limited to entrance angles of 45 degrees or less. This paper presents a methodology to capture images of a retroreflective material at entrance angles between -4 and 75 degrees and observation angles between 0.2 and 1 degree, calculating the coefficient of retroreflection and retroreflected luminance from the images.

• Visibility and lighting

A Method for Mapping a Light Source Utilizing HDR Imagery

Cornetto, A., Suway, J.

SAE Technical Paper

The method presented in this paper utilizes commercially available still cameras with CCD sensors to capture high dynamic range images of a light source in the far-field. This HDR image can then be used as a projection map in a physically based render engine to accurately represent any light source. The technique is validated against the illumination distribution determined by a photometer and real-world spot measurements.

• Visibility and lighting

Quantifying Engine Braking for Various Common Street Motorcycles

Jansen, H., LeBlanc, B., Wilhelm, C., Shaw, T., Lowi, A.

SAE Technical Paper

Motorcycle engine braking was measured in each forward gear for a cross-section of typical street motorcycles. Using GPS data acquisition and video, deceleration relative to speed was examined. Motorcycle characteristics included various engine displacements and types of motorcycle. The data acquired gives more insight into the extent to which engine braking is a factor for deceleration, a topic which had not been addressed in a peer-reviewed journal article to that date.

• Motorcycle
• Testing and instrumentation

Validation of the Cycles Engine for Creation of Physically Correct Lighting Models

Cornetto, A., Suway, J.

SAE Technical Paper

The process presented in this paper utilizes the Cycles render engine within Blender, allowing an accident scene to be recreated in three dimensions including its natural and artificial light sources. In this paper, we define and validate the relationship between strength units in Cycles and photometric quantities and illustrate that the lighting produced is based on the physics of light.

• Visibility and lighting

Comparing the Accuracy of Image Based Scanning Techniques to Laser Scanners

Grimes, C., Roescher, T., Suway, J., Welcher, J.

SAE Technical Paper

This paper compares a FARO Focus laser scanner, Pix4DMapper, and Agisoft’s Photoscan point cloud data to FARO ARM measurements of vehicles, other transportation devices and architectural features. It was shown that the Pix4DMapper and Photoscan point cloud data resulted in detailed and accurate point cloud data compared to the FARO ARM measurements, demonstrating contemporary photogrammetry software as an accurate, time and cost effective alternative to laser scanners.

• Photogrammetry and mapping

Eleven Instrumented Motorcycle Crash Tests and Development of Updated Motorcycle Impact-Speed Equations

Peck, L., Manning, J., Bartlett, W., Dickerson, C., et al.

SAE Technical Paper

Eleven instrumented crash tests were performed as part of the 2016 World Reconstruction Exposition, using seven Harley-Davidson motorcycles and three automobiles. Seven tests were performed at speeds between 30 and 46 mph while four low-speed tests established the onset of permanent motorcycle deformation. Data from these tests, and other published testing, was analyzed to determine the accuracy of available models when predicting impact speed.

• Motorcycle
• Testing and instrumentation

Exploration and Validation of the Ducati Data Analyzer

Peck, L.

Accident Reconstruction Journal, January/February 2018

This paper researched the Ducati Data Analyzer to determine its accuracy and validity.

• Motorcycle
• EDR and telematics

Transport Canada Commercial Bus HVEDR Feasibility Study

Armstrong, C., Higgins, B., Engleman, K., et al.

Transport Canada, final report

This summary report discusses the implications for developing a commercial passenger bus event data recorder standard, focusing on the feasibility of equipping heavy vehicle event data recorders in motorcoaches, buses and school buses. A review of international studies suggests that the use of EDR/HVEDRs in commercial fleets can improve accident rates, driver safety and training, and crash analysis.

• EDR and telematics

Commercial Vehicle Global Positioning System Based Telematics Data Characteristics and Limitations

Steiner, J., Armstrong, C., Kress, T., Walli, T., Gallagher, R., Ngo, J., et al.

SAE Technical Paper

User segment GPS telematics data generated during typical vehicle dynamic maneuvers of medium-duty commercial delivery vans was studied and their accuracy analyzed. The telematics data validity and reliability was assessed by comparison to data gathered using the GPS based Racelogic VBOX III data acquisition system with a corrected signal for baseline reference. The findings present the calculated accuracies for speed and position data.

• EDR and telematics

An Analysis of EDR Data in Kawasaki Ninja 300 (EX300) Motorcycles

Fatzinger, E., Landerville, J.

SAE Technical Paper

Various electronic control units from Kawasaki Ninja 300 motorcycles were tested in-situ to examine the capabilities and behavior of the event data recorders. Numerous tests were performed to establish the algorithms that cause the EDR to record data. It was determined that the recording trigger was caused by activation of the tip-over sensor, and that an event was only recorded if the motorcycle had rear wheel movement at shut-down or the rear wheel decelerated suddenly in the seconds before it. Data elements were stored at either 10 Hz or 2 Hz for a total of eight seconds before the commanded engine shut-down.

• Motorcycle
• EDR and telematics

A Method for Digital Video Camera Calibration for Luminance Estimation

Suway, J., Suway, S.

SAE Technical Paper

In this paper, the authors present a methodology for calculating luminance from a digital video camera. The methodology allows the user to mount a camera near the driver’s eye location and drive through a scene capturing video; still images are then exported and analyzed to create a luminance map. The resulting estimates were compared to values measured with a Konica Minolta LS-100 and shown to be repeatable and accurate across an entire scene.

• Visibility and lighting

Comparing a Timed Exposure Methodology to the Nighttime Recognition Responses from SHRP-2 Naturalistic Drivers

Muttart, J., Dinakar, S., Suway, J., et al.

SAE Technical Paper

A closed road outdoor study and an indoor study were conducted using an automatic shutter system to limit observation time to approximately one quarter of a second. Results showed a positive correlation to naturalistic responses, providing a validation of the time-limited exposure technique. This technique is safe and simple to conduct and was not subject to observer hypersensitivity as were other nighttime recognition techniques.

• Human factors
• Visibility and lighting

The Effect of Tire Pressure on Deceleration of a Motorcycle Under Application of the Rear Brake Only

Peck, L., Deyerl, E., Rose, N.

Accident Reconstruction Journal, July/August 2017

This study looked at motorcycle deceleration rates with respect to varying tire pressure.

• Motorcycle
• Testing and instrumentation

Is a Protocol for Measuring Aged Retroreflective Sheeting Warranted? Retroreflectivity Measurements of 191 Trailers from 36 States

Muttart, J., Dinakar, S., Suway, J., et al.

Transportation Research Board

A handheld retroreflectometer was used to obtain readings from in-use trailers, and a measurement protocol was developed for roadside locations. Measurements were then made of 191 randomly selected trailers at DOT inspection locations and rest areas in five states. Significant decreases in retroreflectivity were associated with trailer age and level of dirtiness; dirtiness alone decreased readings by approximately 25%. Of the measurements on each trailer, 34% were less than the minimum standard for white sheeting and 26% were less than standard for red sheeting.

• Visibility and lighting
• Testing and instrumentation

Motorcyclists’ Glance Behaviors at Unsignalized Intersections: Left Turn across Path

Muttart, J., Bartlett, W., Peck, L., et al.

Transportation Research Board

The behaviors of twenty participants licensed to both drive and ride were compared against ten participants who only held a driver’s license, riding and driving the same test route. Vehicle data were collected using a VBox and eye movements recorded using an eye tracker. Driver-riders executed a greater proportion of glances ahead while turning left at the stop-controlled intersection compared to the driver-only cohort, and no differences were found between driver-riders when they were riding versus driving.

• Motorcycle
• Human factors

Nighttime Photography and Videography: Techniques and Tips

Young, J., Muttart, J., Suway, J.

Proceedings of the Human Factors and Ergonomics Society

Nighttime collisions with motorcycles, pedestrians, cyclists, skateboarders, or wildlife will often require the investigator to assess the visibility of the struck object from the driver perspective at the time of the collision. Since lighting, weather and traffic conditions are continually changing, the ability of the investigator to create a perfect re-enactment is, by definition, not usually possible. This panel discussion shares the combined experience of the panelists regarding tried-and-tested best practice techniques for conducting nighttime collision re-enactments.

• Visibility and lighting

Influence of Taillight Width on the Ability to Recognize Closing Speed, Closing Distance, and Closing versus Separating

Muttart, J., Dinakar, S., Suway, J., et al.

Proceedings of the Human Factors and Ergonomics Society

Observers with valid CDL and non-commercial licenses were shown video clips showing a slower moving lead vehicle. Observers consistently believed the narrower taillight configuration was farther away despite the vehicles’ headlights being on, and perceived the wider taillight vehicle to be closing faster when viewing at distances closer than 128 m. Drivers with CDL licenses performed no better or worse than non-commercial drivers, supporting the hypothesis that these crashes might be related to human limitations rather than driving experience or inattention.

• Human factors
• Visibility and lighting

A Quantitative Method for Accurately Depicting Still Photographs or Video of a Night-Time Scene Utilizing Equivalent Contrast

Suway, J., Welcher, J.

SAE Technical Paper

This study presents a method for calibrating photographs and video, for use and display on printers, computer monitors, televisions or other displays, with a quantitative method. This method removes potential interpretation bias and provides a scientific approach for determining if a photograph or video accurately depicts the contrast of the subject scene.

• Visibility and lighting

The Accuracy of an Optimized, Practical Close-Range Photogrammetry Method for Vehicular Modeling

Peck, L., Cheng, M.

SAE International Journal of Transportation Safety 4(2):245–266

Three targeted vehicles of varying size were measured using an optimized, practical photogrammetry technique and the results compared to measurements acquired via total station. The average residual between corresponding photogrammetry and total station points was 1.7 mm (N = 258, SD = 0.8 mm) with a 95% confidence limit of 3.1 mm.

• Photogrammetry and mapping

The Effects of Power Interruption on Electronic Needle-Display Motorcycle Speedometers

Fatzinger, E., Shaw, T., Landerville, J.

SAE Technical Paper

Six electronic needle-display speedometers from five different manufacturers were tested to determine the behavior of the gauges following a power interruption and impact. The observed change of indicated speed was within plus or minus 10 mph upon power loss. Speedometers were additionally subjected to impact testing on a linear drop rail apparatus to measure the minimum acceleration capable of causing needle movement.

• Motorcycle
• EDR and telematics
• Testing and instrumentation

Application and Use of Linear Interpolation Models: A Case Study

Hunter, E.

HVE White Paper WP-2016-1

Computer simulations are often used to analyze vehicle motion and impact forces in accidents, but where a vehicle has interacted with a roadway object the simulation model may not be able to model the interaction. Some cases involve an object penetrating the vehicle with forces small enough that they need not be calculated, while the specific motion of the object and the vehicle can still be modeled through multiple simulations. This case study examines using the SIMON simulation model together with EDGEN or similar linear interpolation programs to solve specific collision sequences and collision trends.

• Accident reconstruction

Retroreflective DOT-C2 Tape Performance in Relation to Observation and Entrance Angle: A Real World Study

Suway, J., Welcher, J.

SAE Technical Paper

Using different vehicles, with differing headlight housings, bulb types, headlight height, occupant seating height, and headlight spacing, the performance of different types and manufacturers of retroreflective tape was quantified at different entrance angles. In this study, 3M 963, 3M 983, Grote, and Trucklite DOT-C2 retroreflective tape were used, and the effect of change in observation and entrance angle was studied.

• Visibility and lighting
• Testing and instrumentation

Quantifying Retroreflective DOT-C2 Tape Performance using a Retroreflectometer

Suway, J., Welcher, J.

SAE Technical Paper

The authors quantified the performance of a range of popular, commercially available DOT-C2 retroreflective tapes with a retroreflectometer. A RoadVista 932 handheld retroreflectometer was used to measure entrance angles of 0, 4, 10, 20, 30, and 45 degrees with observation angles from 0.2 to 2.0 degrees. As discussed in ASTM E810, each piece of tape was measured at rotation angles of 0 and 90 degrees.

• Visibility and lighting
• Testing and instrumentation

Calculating Three Dimensional Stiffness Coefficients for Use in Three Dimensional Simulation Modeling for Accident Reconstruction

Cornetto, A., Suway, J., et al.

SAE Technical Paper

The crash pulse, along with vehicle mass and impact speed, are used to calculate the force acting on the vehicle and the associated deflection time history. A technique for determining the area-deflection function is created from a computer model of the vehicle, HVE-SIMON, and basic photo-editing software. The resulting crash pulse and displacement-time history predicted using the derived three dimensional stiffness coefficients are compared to data from NHTSA crash tests.

• Accident reconstruction

Comparison of HVE Simulations to NHTSA Full-Frontal Barrier Testing: An Analysis of 3D and 2D Stiffness Coefficients in SIMON and EDSMAC4

Suway, J., Cornetto, A., Wahba, R., Bayan, F.

HVE White Paper HVE-WP-2014-2, presented at the 2014 HVE Forum

SIMON simulations run with derived three-dimensional A, B, C, and D stiffness coefficients were compared against SIMON and EDSMAC4 simulations using the default HVE stiffness parameters, with all three compared to the NHTSA crash test data for crash pulse duration, shape, and peak, and for crush over time. In 6 of the 12 cases the SIMON simulations using the derived 3D coefficients matched the crash pulse better than either default; in 3 cases a default performed better, and in the remaining 3 the result was mixed.

• Accident reconstruction
• Testing and instrumentation

Three Dimensional Simulation of a Crash Test Series in SIMON — Utilizing A, B, C, and D Stiffness Coefficients

Suway, J., Cornetto, A., Wahba, R., Swanson, J., Bayan, F.

Collision: The International Compendium for Crash Research, Volume 9, Issue 1

• Accident reconstruction

Motorcycle Sliding Friction for Accident Investigation

Peck, L., Focha, W., Gloekler, T.

Proceedings of the 10th International Motorcycle Conference, Institute for Motorcycle Safety

This research examined 15 actual crashes of motorcycles equipped with frame sliders and established the related drag factor using 5 and 10 Hz GPS data acquisition, with many of the crashes also documented on synchronized onboard video. Fourteen controlled tests were then performed with motorcycles not equipped with frame sliders. The average drag factor was 0.45 g for the track crashes and 0.48 g for the controlled tests, and the data showed that frame sliders do not lower the drag factor of a sport bike but increase it.

• Motorcycle
• Testing and instrumentation

Biomechanic Analysis of Injury Mitigation Performance for Novel Helmet Design

Shaw, T.

Master's thesis, San Diego State University

Head injuries are a concern for athletes and motorcyclists, and even relatively low-energy impacts can cumulatively have impairing effects. Helmets seek to prevent these effects generally by lessening accelerations experienced by the brain. A new type of helmet has been created which differs significantly from conventional designs, consisting of an array of elastomeric rubber dampers in addition to the traditional crushable foam cushion. This thesis discusses the design of the Omni Directional Suspension helmet and its potential to mitigate brain injury.

• Biomechanics
• Motorcycle

Stiffness Coefficients of Heavy Commercial Vehicles

Poirette, N., Bayan, F., Suway, J., Cornetto, A., Cipriani, A., Wahba, R.

SAE Technical Paper

Stiffness coefficients for passenger vehicles are well publicized through the federal and insurance-industry test programs, but the energy absorption characteristics of heavy commercial vehicles are far less available. This paper presents a methodology using video image analysis, validated against a NHTSA full scale frontal barrier test and then extended to other test videos, to derive stiffness coefficients for heavy commercial vehicles.

• Accident reconstruction

Tractor-Semitrailer Stability Following a Steer Axle Tire Blowout at Speed and Comparison to Computer Simulation Models

Cornetto, A., Bayan, F., Dunn, A., Tanner, C., et al.

SAE Technical Paper

This paper documents the response of a tractor-semitrailer following a sudden air loss in a steer axle tire at highway speed. An instrumented left steer axle blowout test was performed at approximately 55 mph on dry concrete with the vehicle at one half payload, recording roll, yaw, pitch, accelerations, lateral and longitudinal speeds, and steering wheel angle. The test data are compared against the SIMON model within the HVE environment and against a modified TruckSim model, which carries no blowout model of its own.

• Accident reconstruction
• Testing and instrumentation

Brake Characteristics for a Bobtail Vehicle

Bayan, F., Cornetto, A., Dunn, A., Wahba, R., et al.

SAE Technical Paper

Published bobtail testing data are limited, and the difference in deceleration between a bobtail configuration and a tractor-trailer had not been fully evaluated. This paper presents braking characteristics from full scale instrumented testing of a bobtail vehicle at 30 and 60 mph on dry concrete, and compares them both to testing of the same tractor configured with a trailer at different loads and to results published in the literature.

• Accident reconstruction
• Testing and instrumentation

A Comparison Between a Real World Crash Test, HVE Simulation and 3D Scanning

Suway, J., Cornetto, A., Swanson, J., Bayan, F., Wahba, R., Cipriani, A.

Collision: The International Compendium for Crash Research, Volume 7, Issue 2

• Accident reconstruction
• Photogrammetry and mapping

NHTSA’s Test Procedure Evaluations for Small Overlap/Oblique Crashes

Saunders, J., Craig, M., Suway, J.

22nd International Technical Conference on the Enhanced Safety of Vehicles, Paper 11-0343

After concluding that poor structural engagement — corner impacts, oblique crashes, impacts with narrow objects, and heavy vehicle underrides — was the primary cause of continuing frontal-crash fatalities, NHTSA began investigating crash test protocols that replicate real-world injury potential in small overlap and oblique frontal offset impacts. The test program compared vehicle-to-vehicle results against moving deformable barrier-to-vehicle and pole tests using the same baseline vehicles, first on vehicle crash metrics — pulse, change in velocity, and interior intrusion — and then on injury assessment.

• Accident reconstruction
• Testing and instrumentation

Glancing and Stopping Behavior of Motorcyclists and Car Drivers at Intersections

Muttart, J., Peck, L., Guderian, S., Bartlett, W., et al.

Transportation Research Record 2265:81–88

A study compared the intersection behavior of an experienced group of motorcyclists when riding a motorcycle against their behavior driving a car over the same low-volume open roads, wearing eye-tracking equipment with both vehicles instrumented with an accelerometer and GPS. Participants were more likely to make last glances toward the direction of the most threatening traffic before turning when driving than when riding, and motorcyclists were less likely to come to a complete stop at a stop sign. The results suggested that threat-response and delayed-apex techniques should be added to the training curriculum.

• Motorcycle
• Human factors

Influence of Riding Experience on Glance Behavior, Brake Response Time and Deceleration Rates by Drivers and Motorcyclists

Muttart, J., Fisher, D., Kauderer, C., Bartlett, W., Peck, L., et al.

Driving Assessment Conference 6:461–468

The performances of 23 participants were analyzed while they drove a car and rode a motorcycle over the same low-volume open roads, wearing eye-tracking equipment with both vehicles instrumented with an accelerometer and GPS, and braking to a stop when an LED mounted in front of them was illuminated. Motorcyclists spent less time glancing toward the road ahead and made fewer last-glances toward the most threatening traffic before turning than they did when driving; their response times were similar, but they decelerated less sharply.

• Motorcycle
• Human factors

Dynamic Failure Properties of the Porcine Medial Collateral Ligament-Bone Complex for Predicting Injury in Automotive Collisions

Peck, L., Billiar, K., Ray, M.

The Open Biomedical Engineering Journal 4:77–84

The goal of this study was to model the dynamic failure properties of ligaments and their attachment sites to support more realistic dynamic finite element models of the human lower extremities for automotive collision simulation. Twelve porcine medial collateral ligament-bone complexes were held in a custom fixture in a drop tower to apply axial impulsive impact loads at strain rates from 0.005 to 145 per second. Failure loads ranged from 384 N to 1184 N and increased with the applied strain rate, and 75% of the ligaments failed by tibial avulsion.

• Biomechanics

Validation of a New Finite Element Model for Human Knee Ligaments for Use in High Speed Automotive Collisions

Silvestri, C., Peck, L., Billiar, K., Ray, M.

ASME 2009 Summer Bioengineering Conference

A finite element model of the human knee ligaments was developed and validated to predict occupant injury potential in high speed frontal collisions. Dynamic failure properties measured from porcine medial collateral ligament-bone complexes at strain rates up to 145 per second, where failure load depended on ligament geometry and applied strain rate, were integrated into the model, which was then validated against knee ligament dynamic tolerance tests in the literature.

• Biomechanics

Analyzing the Trip-Phase of Soft-Soil Rollovers

Grimes, W., Balasa, J., Hunter, E., Stevens, D.

SAE Technical Paper

Rollover collisions sometimes involve a vehicle sliding and plowing on a soft-soil surface, and little has been published on the deceleration rates involved. Previous tests of a 4-door sedan sliding sideways and plowing through soft soil were modeled in HVE and SIMON with the plowing forces represented by a series of friction multipliers, and an SUV was simulated crossing the same surface. The results indicate that the average deceleration rate for either vehicle sliding sideways on this surface may be approximated by the vehicle’s static stability factor.

• Accident reconstruction

Extracting Tire Modal Parameters from Test Data

Grimes, W., Balasa, J., Hunter, E., Vadnais, T.

SAE Technical Paper

Computer models used to study crashes require reliable vehicle information, and tire parameters are usually the hardest to obtain — analysts routinely fall back on default or typical values. In 1999 Engineering Dynamics Corporation conducted a tire test series to address this. This paper presents an overview of that test data and a technique for extracting the tire parameters simulation models require from the raw collected data.

• Accident reconstruction
• Testing and instrumentation

Extracting Tire Model Parameters from Test Data

Grimes, W., Hunter, E.

HVE White Paper WP-2001-4

Tire parameters are difficult to obtain and analysts routinely use default or typical values instead. Engineering Dynamics Corporation conducted a tire test series in 1999 to produce data for studying motor vehicle performance; this paper describes extracting cornering stiffness, lateral force versus slip angle tables, and friction parameters from that raw data for use in the HVE tire database.

• Accident reconstruction
• Testing and instrumentation