Volume 15, Issue 1 by Collision Publishing

ollision C

Volume 15 Issue 1

The International Compendium for Crash Research

Comparison of Occupant Stress in Frontal Collisions with varying degrees of seat belt use

Crash-Induced Yaw Motion on Airbag Control Module Delta-V

Legal Challenges

Regarding EDR Data In Testimony includes “Mock Deposition”

Corrections to Off-axis Delta-V Measurements from Event Data Recorders

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Crash site evidenCe

A 2010 Chevrolet Equinox SUV attempted to make a left turn in front of a 2003 Dodge Ram pickup. The pickup was in the middle northbound lane when it struck the left-rear side of the SUV, causing both vehicles to rotate CCW to their final rest positions. The right-rear passenger in the SUV suffered significant facial injury, but there was no physical evidence on the back of the right front seat. How did the facial injury occur?

For more information on the capabilities of HVE please visit edccorp.com

HVE directly answers the following questions using Newton’s laws of motion:

Questions

Answers

Impact Speeds

SUV: 22 – 25 mph Pickup: 42 – 45 mph

Peak Impact Force

SUV: Fx= -37,850 lb, Fy= 66,350 lb, Fz= -1,560 lb Pickup: Fx= -71,400 lb, Fy= -26,700 lb, Fz= 1,880 lb

Peak Impact Acceleration

SUV: 18 – 23 g Pickup: 12 – 15 g

Peak Angular Velocity

SUV:

~ -340 deg/sec

PDOF

SUV:

~ -61 deg

Occupant Analysis (Right-Rear)

Seat Belt Status: Unbelted General Motion of Occupant: Left/Forward Facial Contact Detected: Left Front Seat Headrest

Required Technologies

SIMON 3-D Vehicle Dynamics Simulation Model DyMESH 3-D Collision Model GATB 3-D Occupant/Pedestrian Simulation Model

Other software may claim to answer these questions. Have you closely evaluated their claims and the basis for their results?

To learn more about HVE and all of the available tools for crash investigators, call 503.644.4500 or visit www.edccorp.com. Our professional sales staff will help you get started using HVE today!

Knowledge = Power 7096-0820

15.1-FrontCover.indd 2 Rear Occupant

Engineering Dynamics Company, LLC • 550M Ritchie Hwy #128, Severna Park, MD 21146 USA • Phone 503.644.4500 • www.edccorp.com

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Contents

Volume 15 Issue 1

inside

Letter From the Editor (Survey Results)

Collision Magazine Info and Advertiser Index

features 6

Corrections to Off-Axis Delta-V Measurements from Event Data Recorders

by Bob Scurlock, Andrew Rich, and Kyle Poe

Aftermarket ECU’s for Crash Reconstruction in a Growing UTV Market by David Carr

An Overview of the Subaru Eyesight Advanced Driver Assistance System by Shawn Harrington

Crashology: Validation of Ford SG3v1 Speeds Acquired and Derived with Berla iVe by Wesley Vandiver and Robert Anderson

Legal Challenges Regarding EDR Data in Testimony by James Norris and David A. Chapman

Crash-Induced Yaw Motion Effects on Airbag Control Module Delta-V by Micky Marine and Steve Werner

Comparison of Occupant Stress in Frontal Collisions with Varying Degrees of Seat Belt Use by Annika Kortmann

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Corrections to Off-Axis Delta-V Measurements from Event Data Recorders Bob Scurlock, Ph.D., ACTAR

ntroduction

Andrew Rich, BSME, ACTAR

In this article, we derive a mathematical transformation which corrects ∆v measurements from event data recorders at arbitrary positions in a vehicle to the equivalent values at the center-of-gravity. The method is illustrated using staged collision data. We also demonstrate the method’s consistency with simulation.

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Kyle Poe

Use of EDR Data It has become increasingly common for event data recorders (EDRs) to play a central role in accident reconstruction analyses. Both pre-crash speed data as well as acceleration and change-in-velocity (CG) data can provide extremely valuable constraints for the analyst’s calculations and corresponding opinions. Though it is common for event data

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recorders to be located very near a vehicle’s CG, this is not always the case. The analyst must be aware of how an EDR’s distance from a vehicle’s CG can cause inaccuracies to be introduced into an analysis if not properly corrected for. 1,2 Even when near or at the center-of-gravity, it is important for the analyst to be aware of how EDR-based results may be affected by issues such as large rotational velocities. Below, we develop a mathematical transformation to correct for EDR displacement from the CG.

Position of Points in a Moving Reference Frame

Mathematical Development of Transformation Equations

where is the position vector of the moving reference is the frame’s origin with respect to the inertial frame, position of point P with respect to the moving reference frame, and is the position of point P with respect to the inertial frame (Figure 1).

We begin with a rigorous derivation of the equations needed for our inverse transformation from EDR measured at the center-of-gravity based on classical to equivalent mechanics. For a thorough review of classical mechanics, we refer the reader to reference. 3

The position of an arbitrary point, P, can be specified with respect to an inertial frame (Earth frame), O, as the vector sum of P’s position with respect to a moving reference frame, O', and the position of the moving reference frame’s origin with respect to the inertial frame. That is,

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Aftermarket ECU’s for Crash Reconstruction in a growing David Carr UTV market Impact Collision Forensics

rash/Event Data Recorder (CDR/EDR) technology has become an integral part of modern traffic crash reconstruction. Many non-automobiles that are involved in on-road and off-road crashes do not come equipped with stock or OEM electronic recording capability. However, the discovery process described in this case study ultimately revealed that recording capabilities can be an aftermarket addition for vehicles such as UTV’s, ATV’s, Motorcycles, Street Racing Imports, and even boats. These aftermarket components are becoming affordable and easier to program without specialized equipment and training.

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I would also argue this data is just as useful, if not more useful than, automobile CDR/EDR data we have traditionally seen for crash reconstruction. Motorcycles and street racing have remained popular, but Utility Terrain Vehicle (UTV) sales have exploded in recent years. People have been interested in powersports recently, due to its ability to offer affordable and fun outdoor recreation. In 2018 the powersport industry has trended upward and is not showing any signs that it will stop. There were Eleven Billion dollars in UTV sales in 2018.

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With the COVID 19 restrictions sales have spiked even higher. People are spending their money on UTV’s and outdoor equipment instead of going on cruises and travelling vacations. With UTV sales spiking, combined with the “Do It Yourself ” (DIY) movement, there has been solutions for consumers seeking custom options and creating high performance vehicles on a family budget. The ECU Master Black and ADU Display (Figure 1) adds recording capabilities in a UTV which exist even without any dashboard displays or other visible clues. This can make an investigators job very difficult because it doesn’t look like the vehicle has been modified. ECU Master Black and the Advanced Display Unit (ADU) displays shown on Figure 1- above, offer affordable and easy to program CAN bus solutions for modern spark control engines. It offers access to and control over several analog and digital inputs. The ADU display alone has GPS and CAN connections that may contain data, and often are overlooked during inspections (they look like a typical digital speedometer). The GPS and CAN connections are in the rear of the ADU and can only be seen if the unit is removed from the dashboard. Owners with these setups are now able to control wheel speeds and creating ABS or traction control for vehicles not equipped from the factory with these options. You can

control and monitor pressures, temperatures and more. Customers are now fully customizing these vehicles for their specific applications. Many available accessories and control panels allow for a customizable experience and full tuning control. All programming needs are available on the manufacturer’s website. You can download a free software, read the manual, and watch “YouTube” videos to set up the system from start to finish. Another popular use for ECU Master is data logging and track positions. This is also an advantage over typical EDR Data stored in vehicles after an event that causes a record to be stored. This data logging is live and constant for the entire trip of the vehicle. The ADU can use a CAN connection and may be equipped with a GPS connection. The EMU is using a CAN connection with installed inputs. These systems record data that includes speed, acceleration, throttle position (%), gear position, engine pressures, RPM, and angular rates on three planes. These systems record each at their own specific rates, I have found them to typically be from 5 HZ to 25 HZ. The upper sampling limit of the system is set at 500 samples per second. The plug and play adapters allow this unit to connect to a variety of manufactured motors and vehicles on and off the road. These units may even be installed in the next Domestic or Import motor vehicles you inspect after a collision on the road. You might not know they exist under the damaged hood of the next Honda or Muscle car you inspect.

Figure 1: ECU Master Black, EMU and ADU www.collisionmagazine.com

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An Overview of the Subaru Eyesight Advanced Driver Assistance System

ntroduction What reconstructionist wouldn’t want a set of dual color cameras in the front seat of the collision they are investigating? With the development in the North American market of a stereo camera Advanced Driver Assistance System (ADAS) known as EyeSight in 2013, Subaru has officially piqued the datahungry curiosity of the accident reconstruction community. The main question vexing reconstructionists: is there any data contained within this camera-based Subaru EyeSight system that can be accessed and analyzed by investigators?

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Shawn Harrington Forensic Rock

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Along with determining the ultimate answer to this question, this article will investigate the history of the Subaru EyeSight system, present testing analyzing automatic cruise control, establish gap definitions, and evaluate the automatic emergency braking functionality of the system. In addition, a novel approach to develop a more costeffective (i.e. DIY “cheaper”) methodology for creating a build-your-own ADAS vehicle separation system will be presented.

History and Explanation of Subaru EyeSight in North America The first-generation Subaru EyeSight system was introduced in Subaru’s home country of Japan in 2008. After the success of the system in Japan, Subaru introduced the EyeSight system into the Australian market in December 2011.

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crash·ol·o·gy THE SCIENCE OF CRASHES Wesley Vandiver

Robert Anderson

Collision Forensics, Inc.

Biomechanics Analysis

Validation of Ford SG3v1 Speeds Acquired and Derived with Berla iVe

or collision reconstructionists, the ability to retrieve digital evidence of vehicle speed around the time of particular incident can yield key evidence in an investigation. The acquisition of vehicle speed data from Event Data Recorders (EDRs) has become commonplace and is a routine item on the checklist for those investigating vehicular incidents. Much has been written about the accuracy of EDR data from a multitude of vehicle tests involving actual crashes, simulated crashes, hard acceleration, hard braking, etc. In summary, nearly all experts agree that EDR data is tremendously valuable, but should always be considered alongside the other physical evidence and a properly-done analysis of that evidence as part of a situationally complete reconstruction.

the data acquired and derived from the SG3v1 module under these conditions.

During this testing, the Mustang was driven on a closed highway in Tampa, Florida and subjected to high speeds, hard acceleration, and hard braking. The purpose of this testing was to assess the accuracy of

eled between the points and the time interval. For the purposes of the distance measurement, the iVe software uses the Great Circle Methodology, which is used to calculate the distance between two points

The testing of data from EDRs goes back approximately 20 years. In this time, the collision reconstruction industry has had the opportunity to observe and learn about the limitations of EDR data, including issues such as 1) relationship of impact time to Time Zero values or Time -1 second values, and 2) the effects of wheel slip or yaw on the accuracy of recorded speeds.

The SG3v1 module examined in this research records vehicle speed at 10 Hz, which is sourced from the vehicle CAN bus. This is similar to the way in which a typical EDR sources its speed values. However, the difference lies in the time associated with the speed More recently available to the reconstructionist than readings. A typical EDR assigns a time value to each EDR data is Vehicle System data acquired using Berla recorded speed that is approximately the time before iVe. The focus of this research is Vehicle System data an impact/event. The CAN bus speed recordings in acquired and derived from a Ford SYNC Generation the SG3v1 module are timestamped with the local 3 Version 1 (SG3v1) module in a 2018 Ford Mustang system time and displayed in a Velocity Log within GT that was subjected to instrumented testing. The the iVe software, as seen in Figure 2. SG3v1 module, referred to as the Accessory Protocol The second type of speed data available from this Interface Module (APIM) by Ford, is part of the Mus- system is actually derived from the recording of GPS tang’s infotainment/telematics system and only one track points. The SG3v1 system records the location of the many Electronic Control Units (ECUs) in the of the vehicle at 1 Hz intervals. Therefore, GPS coMustang that has recording capability. This research ordinates are recorded for the vehicle location every is limited to the speed data acquired and derived from one second. With this data, the average vehicle speed the SG3v1 module. An example of an SG3v1 module between track points is derived (calculated) within is depicted in Figure 1. the Berla iVe software based upon the distance trav-

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termined and verified, which is valuable in hit-and-run investigations. Among the numerous ECUs from various manufacturers that are supported by Berla iVe, the SG3v1 is, thus far, unique in that it records CAN bus speed data. Many ECUs record GPS data from which speed can be derived. But, to date, only the SG3v1 module is known to record GPS data alongside CAN bus speed data. This provided an opportunity in this research to compare both GPS-derived speeds and recorded CAN-bus speeds to instrumentation data.

Figure 1: Ford SYNC Generation 3, Version 1 Module on the surface of a sphere. An example of the track point organization within the iVe software is depicted in Figure 3. As can been in Figure 3, derived speeds are listed with their associated timestamps and GPS coordinates. The iVe software can display the recorded track points on various map views. The track points depicted in Figure 4 are for the test data examined in this research with all before-and-after track points hidden from view. These two sources of speed data can provide valuable evidence to an investigator. These may be used to corroborate other speed data from an EDR or results of a traditional evidence-based collision analysis. Furthermore, this data could be the only available evidence of the vehicle location and/or speed if the incident did not involve an impact or did involve an impact that failed to reach the required threshold for recording an EDR event. This phenomenon is now commonplace in collisions involving pedestrians and cyclists. Given that the GPS data is timestamped, the historical whereabouts of the vehicle can also be de-

The testing model for this case was taken from SAE International Technical Paper 2018-01-1442. Included in this publication was a testing protocol for assessing the accuracy of speed data from Ford SYNC Generation 2 and Generation 3 systems acquired by the Berla iVe System. For the testing in this case, the same instrumentation was used. The reference instrument used to collect GPS data was the Racelogic VBOX Sport. The specifications for the VBOX Sport are as follows: •

•

• •

Velocity • Accuracy: 0.1 kph (averaged over 4 samples) • Update rate: 20 Hz • Minimum velocity: 0.1 kph • Maximum velocity: 1800 kph • Resolution: 0.01 kph Acceleration • Accuracy: 0.5 % • Maximum: 4 G • Resolution: 0.01 G Heading • Resolution: 0.01° s • Accuracy: ±0.2° s Position • 2D Position: ±5m 95% CEP * • Height: 5 Metres 95% CEP * *95% CEP (Circle of Error Probable) means 95% of the time the position readings will fall within a circle of the stated radius

Figure 2: The Velocity Log for the CAN bus speeds reported in the SG3v1 module

The test data examined in this paper includes approximately 5 minutes of driving involving continually-changing speeds. The speed range examined is between zero MPH up to approximately 118 MPH with several periods of hard acceleration and hard braking. The analysis was done by comparing each speed recording/calculation by way of its timestamp. The VBOX instrumentation data utilized timestamps based upon Coordinated Universal Time (UTC). For

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Legal Challenges Regarding EDR Data in Testimony James Norris, P.E.

Parham Engineering Consultants, Inc

David A. Chapman, Esq. Lewis Thomason, P.C.

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EDR Summit 2020: The Expert Deposition From David Chapman As part of the 2020 EDR User's Summit in Houston, Texas, accident reconstruction expert James Norris and I conducted a mock deposition in which we presented a series of attorney questions and witness responses based on several different scenarios involving EDR data. The transcript of the mock deposition forms the basis for this article. Unlike physicians, accident reconstruction experts are not immune from subpoenas requiring live testimony at trial in most states. This means that in most circumstances, the expert will testify in a “discovery” deposition before he or she takes the witness stand at trial. A discovery deposition is so named because, in theory, it is the opportunity for attorneys for the other parties in a case to “discover” the opinions held by the expert. Discovery depositions are therefore designed to simply prevent a party from being “ambushed” at trial with the previously undisclosed or unexplored opinions of an expert. In practice; however, the discovery deposition of an expert is more often used by an opposing attorney to “test” the expert and to experiment with different types of examination questions to see which ones may prove most effective at trial. Thus, if an attorney discovers that the expert handles questions regarding certain issues effectively, it is unlikely that he or she will give the expert the opportunity to duplicate that success in front of a judge or jury “when it counts.” See In re NC Swine Farm Nuisance Litig., No. 5:15-CV-00013-BR, 2016 U.S. Dist. LEXIS 89074, *159 (E.D.N.C. July 7, 2016) (citing Polozie v. United States, 835 F. Supp, 68, 72 (D. Conn. 1993) (noting distinction between an attorney's questioning of an expert for discovery purposes versus crossexamination at trial; "Attorneys presumably know what the purpose of a trial deposition is, and they will be mindful of the fact that they will not have another chance to develop fully the testimony of the witness. In cases www.collisionmagazine.com

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involving expert testimony this is particularly the case, and the Court must bear in mind that after taking a discovery deposition the attorney fully expects to examine the expert witness again at trial."). Accordingly, discovery depositions of experts often do not entail actual disagreements regarding the content or meaning of EDR data or numerous other elements of an accident reconstruction analysis. Instead, the deposition often focuses on the attorney’s attempt to make the expert’s methodology appear incomplete or imprecise, and thus, unreliable. Such were the questions posed to James Norris at the 2020 EDR Summit. Readers should keep in mind that the deposition was presented to a live audience, and thus there were multiple instances in which James and I addressed the audience outside the context of the deposition to pass on tips for effective testimony. The “exhibits” to the deposition were a series of slides that accompanied the presentation and that played during the examination. From James Norris: David and I greatly appreciated the opportunity to conduct this mock deposition at the 2020 EDR Summit. The mock deposition expounded upon our presentation titled “Legal Challenges Regarding EDR Data” from the 2018 EDR Summit. As with that presentation, our goal was to get attendees thinking about the potential areas and issues regarding EDR data that they could be confronted with during testimony. Many times, those areas can be addressed with proper training, documentation, and policies/procedures. As an expert witness, testimony is the culmination of our work throughout the lifetime of a case. My personal belief is that we begin preparing for that testimony from Day 1 of a case. We must think comprehensively about our data collection, analysis, and opinions and how to support and defend them in the future. As David mentioned, the deposing attorney will be testing the expert, so we should prepare as such. We hope you enjoy our examples and that it may help in your own development. Collision Magazine - Volume 15 Issue 1 61

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Crash-Induced Yaw Motion Effects on Airbag Control Module Delta-V Micky Marine P.E.

Steve Werner, Ph.D. P.E.

SSi, Phoenix Inc.

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Exponent, Inc.

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ntroduction If one were to examine the velocity change data plot and table of the Crash Data Retrieval (CDR) report shown in Figure 1, without additional knowledge of the event in which the vehicle was involved, it might seem that the event was a very minor one. This would certainly seem to be the case as far as the longitudinal component is concerned as the recorded longitudinal change in velocity (delta-V) is of small amplitude and duration.

Alternatively, if one were to examine the velocity change data plot and table of the CDR report shown in Figure 2, without additional knowledge of the event, it would seem reasonable to consider it to be something more than a minor event and that the delta-V monotonically increased over the 300 millisecond recording time might seem curious. Interest might be piqued regarding the accident mode that resulted in such an exceptionally long pulse duration; one in which a significant delta-V has developed but not yet reached a maximum after 300 milliseconds. Despite the substantial differences between the CDR reports of Figures 1 and 2, they were both imaged from the airbag control modules (ACMs) of the struck (target) vehicle of two very similar two-moving-vehicle impacts. The general impact configuration of these two collisions is depicted in Figure 3. These collisions were eccentric impacts that induced large target vehicle yaw rates. The differences that exist between the CDR reports of Figures 1 and 2 occur because, in collisions that result in significant vehicle yaw rate and heading angle change, the location of the ACM within the vehicle is an eminently important factor. The reason for this is that the response measured by an accelerometer strongly depends on its location within the rotating vehicle. To gain further understanding of this effect, we will review the kinematic equations that govern the response of an accelerometer at a given position in an automobile. Acceleration of a Point on a Rigid Body The kinematic equations that describe the absolute velocity and acceleration at a point of interest on a rigid body are developed through a general analysis of the motion of that point relative to a reference system that is translating and rotating relative to a space-fixed reference system. In Figure 4 the position of a point P on the body is defined with vectors rP (position of point P relative to fixed system), rB (position of a base point B on the body relative to fixed system), and rP/B (position of point P relative to the translating and rotating coordinate system at point B) [throughout this article boldface type will indicate a vector quantity]. www.collisionmagazine.com

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Figure 17: Velocity and delta-V vectors for the T1 target vehicle at 100 milliseconds after initial contact

•

[yellow arrow = initial velocity; red arrow = velocity at 100 ms; green arrow = delta-V • at 100 ms] [green arrow = corrected delta-V vectors; cyan arrow = directly integrated delta-V vectors]

•

Accelerations measured at different locations within a vehicle experiencing crash-induced yaw motion may vary significantly. The variance is strongly dependent on the location at which an accelerometer is installed within the vehicle. Though the acceleration experienced at a given ACM installation location will be accurately measured, and a direct-integration technique properly performed, inaccurate delta-V components can be produced if the vehicle has undergone significant impact-induced yaw motion.

These inaccuracies occur because the vehicle (and therefore the ACM) rotation relative to a space-fixed coordinate system is not accounted for with a direct integration of the accelerometer data.

An accident analyst attempting to interpret ACM data from a vehicle that has experienced crash-induced yaw motion should take care in assessing the delta-V components indicated by the ACM and in using this information for occupant kinematics purposes.

References

1. Greenwood, D., “Principles of Dynamics, 2nd Edition”, Prentice-Hall, Inc., 1988. 2. Society of Automotive Engineers Surface Vehicle Recommended Practice J211-1, “Instrumentation for Impact Test – Part I – Electronic Instrumentation,” Revised July 2007.

3. Marine, M., and Werner, S., “Delta-V Analysis from Crash Test Data for Vehicles with Post-Impact Yaw Motion,” Society of Automotive Engineers, Paper 980219, 1998.

4. Wirth, J., Marine, M., and Thomas, T., “An Analysis of a Staged Two-Vehicle Impact,” Society of Automotive EngiFigure 18: Differing delta-V vectors for the neers, Paper 2000-01-0464, 2000.

T1 target vehicle at 100 milliseconds after 5. Bready, J., Nordhagen, R., Perl, T., and James, M., “Methods impact (green arrow = corrected delta-V vecof Occupant Kinematics Analysis in Automobile Crashes,” Sotors; cyan arrow = directly integrated delta-V ciety of Automotive Engineers, Paper 2002-01-0536, 2002. vectors) 92 Collision Magazine - Volum 15 Issue 1

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Accident Reconstruction ACTAR Accredited Biomechanics CDR / EDR Crush Analysis Drones Forensic Mapping Human Factors Motorcycles Vehicle Systems Visibility The Crash Hub is the leading online Accident

and more ..

Reconstruction Expert Directory. Crash Experts vary by experience, rate and specialties. When evaluating the right expert for your case, make sure you search, review and connect with the expert that best matches your case needs.

www.TheCrashHub.com

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Comparison of occupant stress in frontal collisions with varying degrees of seat belt use Dipl.-Phys. Annika Kortmann

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he biomechanical stress on an occupant in a head-on collision is not only linked to the cabin acceleration of the passenger compartment. Where an airbag is activated, the seat belt and the airbag work together to reduce the relative forward motion of the occupants in the vehicle and minimize the risk of an impact with the vehicle interior. What stress such an impact has on the head, chest, and hips of a passenger and to what extent the improper use of the seat belt affects the biomechanical stress has not yet been tested and examined by accident reconstruction experts. For this reason, a series of experiments were conducted in which a Ford Focus traveling at 50 kph had a head-on collision with a tree and the acceleration sequence of the driver upon collision was measured using a biofidelic dummy fitted with measurement instruments. A total of three tests were performed, in the first test the dummy was not wearing a seat belt, in the second test the chest strap was worn just under the left shoulder and in the final test the three-point safety belt was used correctly. The results obtained are discussed and compared depending on the degree of use of the seat belt. Introduction

A common issue in the reconstruction of accidents is the determination of the biomechanical stress on occupants during a vehicle collision. Known studies (see for example 1,2,3,4,5,6, carried out in cooperation with medical experts showed a connection between the cabin acceleration or change in velocity of the passenger compartment as a result of the collision and the biomechanical stress on the passengers. Tests on volunteers were used to test low-impact rear, front and side collisions. In practice, the load on the occupants was determined by technical experts, who calculated, for example, the vehicle’s average cabin acceleration or the corresponding change in velocity upon collision so that medical experts could use this information to interpret the risk of injury. The actual acceleration of the head, chest, or hips of the occupant is not taken into account in most cases as the rate of cabin acceleration was determined from the vehicle damage. In the case of low-impact collisions, the average cabin acceleration was then correlated with the injuries suffered by the passengers involved in the voluntary tests. In contrast, there are almost no comparable tests using volunteers for high-impact collisions, such as www.collisionmagazine.com

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those that activate the airbag, as the risk of injury is too high. It has only recently become possible to use biofidelic dummies in accident reconstruction, which, in addition to their humanoid physiognomy and comparable movements, can also be equipped with measurement instruments. The acceleration is recorded through triaxial accelerometers in the head, chest and hips, which record at 20,000 Hz (Figure 1). A separate accelerator compares the cabin acceleration of the passenger compartment and records these values synchronously with those of the sensors in the dummy. Was the passenger wearing the seat belt properly? In high-impact frontal collisions (e.g., impact with a tree at 50 kph), the question regularly arises, especially before the courts, as to whether the occupant was wearing their seat belt correctly and, if not, which injuries still would have been suffered had the occupant been wearing their seat belt properly. If experts have access to photos of the vehicle involved in the accident, they may be already able to make a statement about the occupant’s seat belt usage from the position of the seat belt or the deformation of the steering wheel. A seat belt that is firmly locked on the B pillar might indicate that the seat belt was not on at the time of impact and the seat belt pretensioner had locked the seat belt to the B pillar when the ignition was turned. According to Walter 7, an investigation of the seat belt itself in combination with the change in velocity determined to have resulted from the collision also offers an indication of whether the seat belt was used. If such photos are not available or if they are inconclusive, medical experts would have to evaluate the severity of passenger injuries to determine whether the seat belt was used. From a technical perspective, it would therefore be beneficial to have some publicly available test results comparing head-on collisions that occur under the same conditions (collision speed, type of vehicle, impact configuration, etc.) where the only difference on the movement of the occupants and the resulting stress was the use of the seat belt (seat belt used/seat belt not used). This would make it possible to directly compare the effect of a collision on an occupant who was wearing a seat belt and one who was not. Unfortunately, no such tests were available.

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4N6XPRT StifCalcs® 4N6XPRT StifCalcs puts the NHTSA Crash Test database on YOUR 32 or 64 bit MS-Windows computer PLUS calculates A-B-G values and Test Specific Crush Factors based on the NHTSA test data, with no need for you to get on the internet, all for the price of only $700.00*! Can you do this yourself “for free”?? Only if you value YOUR time at $0.00!!

4N6XPRT BioMeknx is designed as a collection of the Biomechanical data of importance to the Accident Investigator into one easily accessible reference location. It is designed as a program to be useful to ALL accident investigators, not just the Biomechanical expert. The program includes: 1. Over 65 printable illustrations and charts 2. 10 Separate categories or sections of information related to forensic biomechanics 3. Information on walking speeds of people from 17 months to > 65 years 4. Calculation modules for: - segment length from total body height, - segment weights and Centers of Mass (CoM) based on total body weight, - Predicted Maximum Walking Speed based on total height 5. Information was obtained by review of over 65 scientific texts, several of which are now "out of print"

www.4n6xprt.com/4n6bm.htm PROGRAM ORDER FORM (Please Print) Contact Name: ________________________________________________ Company: ____________________________________________________ Street: ______________________________________________________ City:____________________ State:____ Zip:__ __ Country: __________ Phone: (_____) _______________ Fax: (_____) ___________________ E-Mail: ______________________________________________________ Expert AutoStats® 4N6XPRT BioMeknx™ Expert Qwic Calcs® 4N6XPRT Ped & Bike Calcs® 4N6XPRT StifCalcs® Expert VIN DeCoder® (pkg) Expert TireStuf® Order Processing

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- 8.50%

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Search for vehicles by entering Year, Make, and Model, or by any combination of: Length, Wheelbase, Weight, Body Style, Make, Model, and Impact location

Enclosed is:

Print out data and stiffness for single tests, or a Test Summary Stiffness Report when more than one test meets your search criteria

Card Number: _______________________________________________ Name on Card: _______________________________________________ Signature: ________________________________________________

For more information, program order form, and sample printouts please visit our web site at http://www.4n6xprt.com. You may also call us at (619) 464-3478 M-F, 9a-5p (PST), if you have specific questions.

www.4n6xprt.com/4n6sc.htm

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Please Make Checks*/Purchase Orders Payable to:

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bosch C DR pr o to o l k it The Bosch CDR Tool is a reliable, versatile, and increasingly powerful industry standard platform that retrieves EDR data from the vast majority of modern vehicles. The CDR Tool software generates a detailed report that has become a vital part of investigations conducted by insurance claims adjusters and Special Investigative Units (SIUs). They are also routinely used by law enforcement agencies and accident reconstructionists. EDR data translated by the Bosch CDR Tool is admissible in court as the CDR reports are used to verify insurance claims and assess vehicle and driver input in the moments leading up to, and during, a crash.

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The CDR Pro Kit is the heart and soul of the Bosch CDR Tool. This package contains all of

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Schedule a webinar or product demo today www.crashdatagroup.com 15.1-BackCover.indd 1

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