Issuu

The International Compendium for Crash Research

In c

Volume 1 Issue 1

Collision: The International Compendium for Crash Research

ollision C Accuracy of Speed Recorded by an SDM & the Effects of Brake & Yaw Events Analysis of the GM Sensing & Diagnostic Module in 360 Degree Linear Momentum Collisions: Real Case Analysis CDR Data Presentation & Validation in Legal Proceedings

Case Study:

Crash Data Retrieval ro up

CDR Conference Proceedings sh

D at

Implementing Policy for CDR

Motorcycle Collinear Collisions Involving Motor Vehicles Equipped with EDRs

Event Calendar

Organization News

Incorporating CDR Services in an Existing Forensic Practice

Volume 1, Issue 1 - June 2006

A Review of Various ACM Module Types & Data Recorded

Premier Issue

Includes CD 2006 CDR User’s Conference

www.CollisionPublishing.com

Collision Safety Institute

Special Offer

The ARC Network is pleased to offer a FREE Collision Safety Institute CDR training course or a cash rebate when you purchase a new Vetronix CDR System through the ARC Network. Also included with your purchase is a FREE one-year membership to the ARC Network. at

In c

CDR

CDR Technician and Data Analyst Training series

Crush Computer not included

The Vetronix CDR System has fast become an indispensible tool of a complete crash reconstruction program. Police agencies, private reconstructionists, engineers, government agencies and other safety researchers have come to the realization that the data stored in the air bag control module and accessible using the Vetronix CDR System is an invaluable part of a complete and thorough crash reconstruction.

CDR System

“Whether for trial, research,

Computer

Air Bag Control Module

Collision Trauma Biomechanics

Pedestrian & Bicycle Reconstruction of Pedestrian or Bicyclist Involved Collisions

Human Factors Human Factors: Understanding Driver Response

D at

ro up

(not included)

Biomechanics

or any other crash related safety program, the CDR System has become an integral reconstruction tool”

Damage And Energy Applications for Collision Reconstruction (CRUSH)

For complete information please contact the ARC Network Toll Free: (866) 223-4984 Email: arc@accidentreconstruction.com

www.CollisionSafety.net

www.cdr-system.com

The Collision Safety Institute (CSI) is an independent traffic collision research, training and consulting organization. CSI’s mission is to provide state-of-the-art training and technology transfer to both public and private entities involved in the analysis and evaluation of motor vehicle collisions, provide technical support to professional associations and organizations in their training efforts and conduct testing and research on surface vehicle collision topics and related technology.

Contents june 2006

In c

of interest From the Editor

Calendar of Events

On The Cover

Organization News

20 (c )

Letter From NAPARS

Photo By: Scott Baker Taken at the Bremerton Race Track in Washington at the 2002 ARCCSI Crash Conference. This was approximately a 52 MPH collision. Trivia: This photo was used as the framework for the ARC-CSI logo.

features The Accuracy of Speed Recorded by an SDM and the Effects of Brake, YAW and other Factors

Analysis of the GM Sensing and Diagnostic Module in 360 Degree Linear Momentum Collisions

CDR Presentation and Validation in Legal Proceedings

A Review of Various ACM Module Types and Data Recorded

Rational Legislative and Organizational Policy for Automotive Event Data Recorders

Practical Ascpects of CDR Using the Vetronix System

Motorcycle Collinear Collisions Involving Motor Vehicles Equipped with EDRs

D at

ro up

Crash Data Case Study

Case Study Solution

case study 28

In c

Conferences & Training

The ARC Network and Collision Safety Institute host the annual premier crash conference, the (c )

ARC-CSI Crash Conference

This conference is designed to be topical, timely and a lasting learning experience for all involved. Every June in Las Vegas, NV you have the opportunity to witness live crash testing first hand, attend presentations by recognized leaders in their field, and leave the conference with crash data in hand including the video, photos, copies of presentations, and related documents.

There is no better opportunity for training. Anywhere.

ro up

The ARC Network and Collision Safety Institute along with Vetronix, CDR Tool User’s Group and other sponsors host the newest conference and training opportunity, the

D at

Crash Data Retrieval User’s Conference (c

This is a comprehensive conference held in Texas each February to publish CDR System related information in the form of peer-reviewed papers, data compendium and the like. It covers legal issues, current legislation, user applications and future updates and developments. Visit us on the Web

www.crashconferences.com

In c up ro G a at D sh ra C 06 20 (c )

Analysis of the GM Sensing and Diagnostic Module in 360° Linear Momentum Collisions

ro up

D at

Event Data Recorder technology is not new, just as airbag technology is not new. Event Data Recorders, (E.D.R.s), have been around in automobiles since the early 1970’s1 . However they have become prevalent in automobiles since the early 1990’s.

only a limited number of vehicles which included pre-crash parameters. Most of the vehicles in that original release included only delta-v data. This data is often ignored and placed in a case file used only for the seatbelt information, if that. However, this information can be very valuable, especially in linear momentum analysis of collisions. The delta-v data gives us information recorded at the time of the crash. This information can validate a reconstruction to an amazing degree. What could be more compelling to a jury than to have the event data recorder on the vehicle involved in the collision agree with the results of the reconstruction.

Event Data Recorder technology is becoming an ever present part of the reconstruction culture. The deltav data can be the most valuable data collected, especially in a linear momentum reconstruction. The purpose of this paper is to discuss how to evaluate a reconstruction and compare what the reconstruction indicates to the instruments on board the crash vehicle, with a primary focus on the delta-v data. The paper will discuss the application of this valuable data and compare it to real world crashes reconstructed utilizing linear momentum techniques.

NTRODUCTION

BSTRACT

- Weston H. Brown Scottsdale Police Department Vehicle Crimes and Reconstruction Unit

Vetronix is the first company to enter into a contract with automakers to create software and hardware capable of downloading this information available to the general public. The first release of the Vetronix Crash Data Retrieval software in 2000 included

Collision 17

CrAsh Data Case Study

(c )

In c

Knowing what to look for and where to find it

- Rusty Haight, Brad Muir eviewing crash data “downloaded” from an air bag control module using the Vetronix Crash Data Retrieval system can be at least confusing when one attempts to evaluate that data in the absence of an understanding of the normal components of a crash: the human, vehicle and environmental (H.V.E) components. At a minimum, a situationally complete* crash analysis needs to be done when one tries to make sense of the downloaded crash data.

both vehicles and photos of the involved vehicles. There are a series of issues offered for evaluation. These issues may or may not be the same from one instance to another but they are selected for discussion here and to give a more narrow focus to the case study at hand.

This case study is offered as an opportunity for the crash reconstructionist who is also trained as a Vetronix Crash Data Analyst to look at a set of case facts and evaluate some commonly encountered issues which often lead to confusion or misinterpretation. This case study is based on a documented crash test so there are “known quantities” involved. The issues and answers associated with this case study are appropriate for this case alone and may not be appropriate or applicable to another crash scenario given varying crash facts.

(1) There are two events recorded for the Cavalier, in what order did they occur?

n this instance, one should review the provided materials in an effort to address these points:

ro up

(2) What is the most probably reason for the first event recorded and displayed in the Cavalier’s download? What action or impact caused the first event recorded by the Cavalier? G

D at

(3) There is an apparent speed loss for the Cavalier over the period approximately 1 second to 2 seconds before “AE” where the reported speed appears to be 31mph then Here, the CDR system operator is given certain data ele- drop to 14 mph. There is a brake switch “on” indicaments from a 2 car crash. A 2001 Chevrolet Cavalier has tion at approximately 2 seconds before “AE” then “off” collided with a 2001 Chevrolet Lumina. One may review at about 1 second before “AE.” With those observations a scale crash scene diagram, data CDR downloads from in mind, what explanation can you give for the apparent * “Situationally complete” is used here to mean a crash analysis based on or which may be limited by (1) policy and/or procedure, (2) existing or available crash facts/evidence, (3) the existence of little or no visible roadway evidence, or (4) an individual analyst’s training and experience. Collision 28

speed loss over that second? One should explore possible explanations including: (3a) that there was “pre-crash data resampling (also know as “data buffering”)” for the “-1” samples and that speed is therefore under reported,

as “on,” the engine RPM is as high as some 3500RPM. What explanation can be offered for this apparent contradiction in the pre-crash data elements? (5a) Identify investigative steps which might be taken to evaluate and explain the apparent contradiction in the pre-crash data seen in topic “5” above.

(c )

In c

(3b) that the brake switch status is reported incorrectly (reversed) for certain Cavaliers including the 2001 year model and this case we’re dealing (6) Relative to the data downloaded from the 2001 Luwith a 2001 Cavalier, mina, there are two events recorded for the Lumina, in what order did they occur? (3c) there is actually braking pre-impact and that means the wheels on the Cavalier are locking and (7) The data downloaded from the Lumina does not discausing the speed to be under reported at the “-1” play any pre-crash data. Would this be an indication of a sample. “power interruption?” (8) The Lumina download shows a non-deployment event. That non-deployment event shows a delta-V of -1.1mph over about 34ms. For the sake of this case study, one may assume that the actual, total delta-V for the Lumina is about -10.3mph. As it relates to this case study, assume that this value may have been calculated as part of a reconstruction. Explain the difference in the calculated delta-V of -10.3mph and -1.1mph as reported in the Lu(5) One may assume for the sake of this study, that mina data report. “redline”on the Cavalier is about 6000RPM. In the Cavalier download report, for the entire time captured for There may be other interesting components or aspects of “pre-crash data,” one sees “0” (zero) for percent throttle; this event that one may want to evaluate but to limit the however, the engine speed captured is as high as more than focus of this particular case study, these are the points se5000RPM. Even when the brake switch status is reported lected. Solutions can be found at page 97.

D at

ro up

(4) The delta-V for the Cavalier appears to be about 15.6mph at what is marked as the “90ms” sample on the delta-V graph and table for the deployment event. After that, in the “100ms” and then “110ms” samples, the delta-V takes an “upturn”or appears to become relatively less severe. What explanation can be given for this apparent “upturn?”

Case study scale scene map

Collision 29

00 00 00 00 00 00 00 00 00 00 A5 A5 A5 A5 75 FD

(c )

In c

B7F0: B7F8:

D at

ro up

k n a bl rve t f le rese e c pa y to p t s s Thi ionall orma nt port f e t in re

2G1WL52J1Y1277477

Collision 42

Page 5 of 6

Printed on:

In c up ro G a at D sh ra C 06 20 (c )

MOTOR VEHICLE EVENT DATA RECORDERS Validation and Use of Data for Admission to the Court

NTRODUCTION

Data collected from vehicle Event Data Recorders (EDRs) has been accepted by courts as evidence to be presented at trial. The validity of the data has been established by testing which has been documented

in scientific, peer-reviewed literature. Technical literature and case studies are presented to demonstrate the accuracy and validity of the data, along with examples to describe the presentation of some critical information to respond to challenges.

Since 1994 data has been available to the accident reconstruction community from Event Data Recorders (EDRs) in certain General Motors automobiles. Since 2000 to 2001, data has also been available from some Isuzu and

BSTRACT

D at

ro up

Guy J. Barbera Olof H. Jacobson Bastiaan E. Cornelissen Christopher A. Thomas and Donald J. Anderson

Collision 43

C D at a ro up

G c

(c ) 06

20 sh

C a

D up

In c

- Sgt Chuck Veppert Ohio State Police

ro up

D at

- The historical progression from data recorded by the early SDMA and SDMB through the current SDMGF and SDMDW modules including a discussion of multiple deployment files in early modules, relatively low maximum deltas-V captured, where 300ms of delta-V vs 150ms may be captured and the apparent uniformity in relatively “early” modules. - Differences in data recorded in Deployment vs NonDeployment events - Cautions related to reviewing or storing events saved as pdf - An explanation of maximum delta-V recorded comparing actual maximum vs data limitations approximation - A discussion of the changing data points recorded over the different models - Data differences in the same module/different car line

The data for this research was collected from CDR downloads performed by the OSHP, from the CDR Yahoo Group website files, and by numerous other CDR users who responded to a request on the CDR Group forum. Each was opened and documented as to the Year/Make/ Model (using the vin if not identified). The data for each file was sorted by module type, with any interesting identifying numbers also noted. The event files submitted by private users for this project will be destroyed after final completion of the spreadsheet. The spreadsheets found on the data CD that comes with this issue of Collision should be considered a “work in progress” and are current to the research as of February 2006. Additional data is still being added to the spreadsheets as they’re found on the CDR User’s Group Yahoo site. 00

- Discussion on the variances observed in what data is recorded on the SDMGF (used in may 2002-2005 models) - Data on FORD RCMs is included, but limited due to the small supply of event files at the time this research was compiled.

s part of the CDR Conference, Ohio State Police Sgt Chuck Veppert presented his research relating to which specific air bag control modules are found in which vehicles currently accessible by the Vetronix CDR System. Sgt Veppert’s presentation was a review of a spreadsheet of the data contained in events files from 16 models of GM and 3 models of Ford ACMs including:

(c )

In c

A Review of Various ACM Module Types and Data Recorded

Collision 53

In c up ro G (c )

MAPSCENES SYSTEMS, THE FORENSIC MAPPING SOLUTION.

DESKTOP MAPPING

• Support for all total stations • View your data at the scene • Easy to use interface • Advanced measuring techniques • Easy linework • MicroSurvey Tracker evidence collector package available

• IntelliCAD drawing engine • Advanced data collector and total station support • Dynamic car builder • Symbol editing tools • Car crush tools • 3D modeling

D at

ro up

EVIDENCE COLLECTION

get yours today, “no strings attached.” www.mapscenes.com

1- 800 - 668 - 3312

MapScenes — the complete forensic mapping system. from certified training, to collecting evidence at the scene, to showing diagrams in court, mapscenes is the only product on the market that is a true system, seamlessly integrating all facets of an investigation into one easy and reliable package. visit our website today — mapscenes.com

evidence cOLLecTiOn sOfTware | desKTOP maPPing sOfTware

hardware

800.668.3312

mapscenes.com

- George J. Hall, P.E.

(c )

In c

Practical Aspects of Crash Data Retrieval Using the Vetronix System

D at

ro up

This paper was written to discuss practical issues for those who may be considering adoption of the Vetronix CDR technology, and provides some management background for those who already have. A decision to become a service provider for this new technology should be made based on consideration of all the costs and commitment required. The cost of adoption of the technology includes not only the direct monetary costs of NTRODUCTION the equipment, ancillary tools, trainMany ACMs write data to ing, hardware and software upgrades, an electronic file in the event but also the in-house labor costs reof a deployment or near-deployment quired to obtain and maintain techof the frontal airbags. Retrieval of nical proficiency. this data can be accomplished using dedicated hardware and software, and this process has come to be known 00

Many airbag control modules (ACMs) write data to an electronic file in the event of a deployment or near-deployment of the frontal airbags. Retrieval of this data can be accomplished using dedicated hardware and software, and this process has come to be known as “Crash Data Retrieval” or CDR. CDR is performed as one component of the reconstruction of a motor vehicle incident. The retrieved data can only be understood and/or interpreted properly when viewed in conjunction with the physical evidence, setting, and environment used to reconstruct the incident. The only way to verify the data obtained via CDR is to compare it against the actual physical evidence and the results from conventional solution techniques, and this can only occur at a point in the reconstruction process when the conventional reconstruction efforts are completed or substantially so. When such an approach is used, CDR becomes another tool in the kit for accident reconstruction, and both compliments and expands the capabilities of conventional reconstruction techniques. The initial costs include the expense

as “Crash Data Retrieval” or CDR. The Vetronix Corporation of Santa Barbara, California, manufactures and sells the only publicly-available equipment for retrieval of crash data from ACMs in General Motors, Ford, and limited models of Isuzu and Saab vehicles. The list of automobile manufacturers that can be accessed using the Vetronix equipment is expected to expand in the near future, and to continue expanding over time.

of the Vetronix CDR kit, ancillary tools, formal training, and overhead/ administrative costs. With regards to CDR technology, formal training is not an option; it should be viewed as a mandatory part of the “commitment” required to institute this service. In addition to the Vetronix kit, additional equipment is required to access the ACM and conduct a download, and a list of equipment is presented. The initial costs and continuing costs to acquire the equipment and develop and maintain technical expertise are discussed. Most technical support is provided via an online forum, and the operation of this forum is discussed. Management options that may help reduce the cost of participating in CDR are discussed. Finally, miscellaneous practical issues based on the author’s experience are also discussed.

BSTRACT

Collision 69

(c )

In c

Figure 32. CDR file for crash test #3: SDM recorded delta-v. (Left) Figure 33. Crash test #3 data from IST accelerometer and Stalker radar. (Right)

Figure 34. Crash test #3 data from IST accelerometer and Stalker radar. (Left) Figure 35. Crash test #3 data from IST accelerometer, Stalker radar, and SDM. (Right)

D at

ro up

Figure 36. Crash test #3 data from IST accelerometer, Stalker radar, and SDM. (Left) Figure 37. Crash test #3 data from IST accelerometer. (Right)

Collision 96

Case Study solution (c )

In c

Knowing what to look for and where to find it

his case study is based on a crash test conducted in Phoenix in July, 2005 for the Southwestern Association of Technical Accident Investigators (SATAI). The Lumina was parked off the road, beyond a curb up on a hard packed, dry (as one may imagine, it was, after all Phoenix in July!) dirt surface. The Cavalier was driven in an arced path leading to the curb, struck the curb then moved over the dirt, uphill to the flat surface and struck the Lumina.

“time between non-deployment and deployment events (sec).” In this instance, it reads “1 (one).” This tells us that the non-deployment preceded the deployment by about 1 second.

Once again the issues raised for discussion here may or may not be the same from one instance to another but they are selected for discussion in this context and to give a more narrow focus to the case study at hand. The issues and answers associated with this case study are appropriate for this case alone and may not be appropriate or applicable to another crash scenario given varying crash facts. Alright, having said that...some answers for the issues posed follow:

Solution: Unlike question #1 above, answering this question requires we know something about the crash itself. In this instance, we have a crash scene and photos of the crash scene that show the path of the Cavalier to a curb then beyond the curb to strike the Lumina. Looking at the data and distances involved, and knowing the non-deployment occurred before the deployment, we can deduce that the curb strike brought about the non-deployment then the collision with the Lumina caused the deployment. This deduction would be consistent with observations at the test and instrumentation used in the test as well and is an example of a situationally complete reconstruction. C

(1) There are two events recorded for the Cavalier, in what order did they occur?

D at

ro up

(2) What is the most probably reason for the first event recorded and displayed in the Cavalier’s download? What action or impact caused the first event recorded by the Cavalier?

Solution: Assume we know little about the event for the moment, the order of events is found described in the CDR report text itself. In this instance, the deployment record and the on-deployment record are both recorded for the same ignition cycle (8978). The key to this solution is to find the line in the deployment file that reads:

(3) There is an apparent speed loss for the Cavalier over the period approximately 1 second to 2 seconds before “AE” where the reported speed appears to be 31mph then drop to 14 mph. There is a brake switch “on” indication at approximately 2 seconds before “AE” then “off” Collision 97

warning lamp is “ON” at the time of the non-deployment (consistent with a previous deployment) and that the line that reads “A deployment was commanded prior to this event)” (“this event” meaning the non-deployment here) reads “YES.” (7) The data downloaded from the Lumina does not display any pre-crash data. Would this be an indication of a “power interruption?” Solution: No, not all modules capture what’s known as “pre-crash data.” In this case, the module was simply not capable of capturing “pre-crash” data.

In c

Solution: Looking back to issue/question 3b in this case study, we see that the car has a manual transmission. The answer is, in this case, that the transmission was down shifted harshly. As a function of that, there was engine braking (further complicating the answer to issue 3c above), the engine RPM revved high and the car was actually slowed. How would you know this in a “real world” case? You may not. You may have to surmise that based on the investigative steps you would take. What cannot be done is try to “tie” throttle and RPM together and draw conclusions from that alone. One must always remember “pre-crash” data is captured asynchronously and each data element is a stand alone, separate observation (c )

(5a) Identify investigative steps which might be taken to (8) The Lumina download shows a non-deployment evaluate and explain the apparent contradiction in the event. That non-deployment event shows a delta-V of -1.1mph over about 34ms. For the sake of this case study, pre-crash data seen in topic “5” above. one may assume that the actual, total delta-V for the LuSolution: The observations of witnesses hearing the en- mina is about -10.3mph. As it relates to this case study, gine revving may well guide the investigator to look at assume that this value may have been calculated as part of this as a possibility but determining what transmission a reconstruction. Explain the difference in the calculated the car has and looking closely at the pre-crash tire marks delta-V of -10.3mph and -1.1mph as reported in the Lumina data report. could help the investigator evaluate this possibility.

D at

ro up

(6) Relative to the data downloaded from the 2001 Lu- Solution: Now, it’s time for a more thorough analysis of mina, there are two events recorded for the Lumina, in the crash. We need to do a more thorough momentum analysis for impact and closing speeds, total delta-V and what order did they occur? then PDOF...but those are the clues. The more complete Solution: In this case, the ignition cycle count for the two answer in the next issue of COLLISION where the topic events points to the observation that the deployment oc- of this section turns to calculating closing speed! curred before the non-deployment. Further, in the nondeployment data section of the report, we see that the

Collision 100

Special Offer

CDR )2

CDR Technician and Data Analyst Training series (c

Crush

Human Factors Human Factors: Understanding Driver Response

Air Bag Control Module

Reconstruction of Pedestrian or Bicyclist Involved Collisions

Computer

(not included)

Pedestrian & Bicycle

ro up

“Whether for trial, research,

Collision Trauma Biomechanics

CDR System

Biomechanics

has fast become an indispensible tool of a complete crash reconstruction program. Police agencies, private reconstructionists, engineers, government agencies and other safety researchers have come to the realization that the data stored in the air bag control module and accessible using the Vetronix CDR System is an invaluable part of a complete and thorough crash reconstruction.

D at

The Vetronix CDR System

Damage And Energy Applications for Collision Reconstruction (CRUSH)

Computer not included

or any other crash related safety program, the CDR System has become an integral reconstruction tool”

In c

Collision Safety Institute

For complete information please contact the ARC Network Toll Free: (866) 223-4984 Email: arc@accidentreconstruction.com

www.CollisionSafety.net

www.cdr-system.com

In c

Collision: The International Compendium for Crash Research

ollision C The International Compendium for Crash Research

Volume 1 Issue 1

Accuracy of Speed Recorded by an SDM & the Effects of Brake & Yaw Events Analysis of the GM Sensing & Diagnostic Module in 360 Degree Linear Momentum Collisions: Real Case Analysis CDR Data Presentation & Validation in Legal Proceedings

ro up G a D at sh ra C 6 00 )2 (c

Volume 1, Issue 1 - June 2006

A Review of Various ACM Module Types & Data Recorded Implementing Policy for CDR Incorporating CDR Services in an Existing Forensic Practice Motorcycle Collinear Collisions Involving Motor Vehicles Equipped with EDRs

Premier Issue Case Study:

Crash Data Retrieval CDR Conference Proceedings Event Calendar Organization News

Includes CD 2006 CDR User’s Conference