On Friday October 16, ATA Associates, Inc. conducted low speed automobile crash tests for an audience of invited guests in the high bay of the ATA facilities near the Johnson Space Center in Houston, Texas. Four in-line crashes were staged in which a "bullet" vehicle struck a stationary "target" vehicle in the rear. Bullet vehicle speeds ranged from 5.1 mph to 10.2 mph. In the first two tests, a 1996 Ford Taurus 4-door sedan (curb weight 3,330 lbs) served as the target and was struck by a 1992 Ford Escort 2-door hatchback (curb weight 2,400 lbs). In the final two tests, the vehicles' bullet and target roles were reversed, and the Escort was struck by the Taurus.
In all four tests, a 3-axis accelerometer set, mounted on the floorboard of the Taurus just ahead of the front seat, monitored the collision-induced accelerations and decelerations of that vehicle. In addition, an instrumented live subject in the driver's seat of the Taurus provided data on the inertial reactions of the human body to the collision impacts. Jody Haselbarth, an experienced motion picture stuntwoman and a veteran of several previous tests at ATA, wore a 3-axis accelerometer set on her chest and a second 3-axis accelerometer set on her head to provide the body response data.
The tests were documented on video from multiple camera angles. After each test, ATA's guests, which included attorneys, safety professionals and law enforcement officers were provided with an immediate review of the data and video that had just been recorded.
According to CEO Bob Swint, "Testing is an important part of what we do as scientists and experts. Testing helps us answer difficult questions and provide solid answers for our legal and industrial clients. ATA's facility is unique in the Houston area. With our 7,500-sq. ft. high bay, ten-ton overhead crane, and 10,000-pound capacity vehicle lift, we are well equipped to perform all manner of testing."
A card game in which the players bet on the top card of the dealers
deck; a game of chance based on guessing and luck. Ironically, FARO
Technologies, Inc., a high tech company in Lake Mary, Florida, has
developed a hybrid measurement tool that gives its users the ability
to record nearly perfect measurements.
Originally designed for assisting surgeons in precision location
of tumors during brain surgery, this highly accurate device uses
analog/digital rotary transducers to measure exact angles and dimensions.
Known as the FARO “arm” because of its appearance, the
device allows for 6 degrees of freedom with a hemispheric measuring
envelope that ranges from 6-12 feet. The FARO arm has developed
to include a wide range of end users. From Boeing, which uses the
arm to measure and inspect jet engines, to General Motors whose
application involves accurately identifying and correcting variations
in their manufacturing procedures.
More recently, FARO has found it’s way into the market of
accident reconstruction with the need to accurately measure crushed
vehicles involved in accidents. Traditionally, vehicle crush measurement
has been a time consuming procedure. Data results generally are
hand written coordinates or measurements generated with tape measures
and documented with photographs. The investigator may leave the
vehicle with an accurate listing of coordinates of the vehicle crush,
but they are only coordinates. Someone now has to take these coordinates
and photographs and create an engineering drawing from them. Depending
on the fidelity of the end product, this could be a long and expensive
task. Using this technique to generate a 3d-surfaced model of a
crushed vehicle simply isn’t practical.
a single point accuracy as low as .0001” and a process that
allows for virtually an endless range, the FARO arm gives the operator
a precise measurement of the entire vehicle in a relatively short
time frame. The procedure consists of:
Setting up the arm next to the vehicle and establishing a coordinate
2. Extending the probe to surface of the object and selecting your
points by pressing a button and,
3. Moving the arm to the next position and starting over again at
step number one.
the data points are selected the computer software builds a surface
between the data points in real time. Points can be taken one at
a time or in a streamline technique that allows for a user set increment.
After taking enough points, you begin to see the 3d-vehicle computer
model beginning to take shape. The investigator walks away with
a highly accurate 3d-computer model of the vehicle. This model can
be used by engineers to measure the amount of crush deformation,
analyzed by biomechanics for passenger biokinematics, and or used
within computer crash simulation or animation of the accident.
Having a computer model of the vehicle preserves it’s current
state and in some instances allows the owner to make repairs and
put the vehicle back into service. Feedback is virtually instantaneous.
Depending on the amount of deformation and if the interior needs
to be captured, most vehicles can be digitized in 2-3 hours.
The application is obviously not limited to just cars. Trucks, tractors,
trailers, boats and just about any component or part that may be
important to a case can be digitized. The unit comes with a very
robust carrying case, which allows for portability of the arm.
Downsides to the FARO arm are minimal but need to be addressed.
Weather can be a factor. The arm cannot be used in the rain. Also,
after setting up the arm, the operator needs to allow approximately
15 minutes for temperature compensation (if there has been a change
in temperature). The probe must touch the surface you are digitizing
to take an accurate point. In some instances, the configuration
of the arm may not allow you to reach an area and hand measurements
may be an alternative.
If you have the money to spend, N Vision in Dallas, Texas makes
a laser attachment to the FARO arm that would allow you to capture
virtually any area of the object. If you do run into a problem,
however, you’ll be glad to know that purchasing a FARO arm
also entitles you to lifetime customer support.
the name suggests, FARO Technologies 6 degrees of freedom digitizer
takes the guesswork out of vehicle crush measurement. If accuracy
is critical to your case, and you need to generate a computer model
of your vehicle or component in a short time frame then you should
consider this reliable and precise FARO arm as an option.
Dynamics Analysis Handbook
Associates is proud to announce the publication of Vehicle Dynamics
Analysis: Handbook of Charts and Tables- with CD-ROM.
The Handbook is a complete reference tool that is a composite of
engineering data expressed in formulas, charts, tables and graphs.
Approximately 80 pages, the Handbook was specifically designed as
a supplement to traditional textbooks. The Handbook covers basic
formulas, acceleration, braking, deceleration, stopping, speed,
maneuvering and curves. It is the ideal resource for those initiated
in the basics of accident reconstruction.
The accompanying CD-ROM contains an application that lets the user
make their own calculations and charts
The Handbook was written for accident reconstructionists, attorneys,
claims adjusters, consulting experts and investigating officers.
While an understanding of physics is helpful in using the Handbook,
it is not absolutely necessary.
variety of expertise contributed to the production of the Handbook.
Authors of the Handbook include Robert Swint, Barry Richard, John
Sweatt and Marvin Larson.
Swint is the CEO and a technical, graphics and animation consultant
at ATA. A former NASA engineer, Mr. Swint has worked in the field
of accident reconstruction for over 20 years. He has lectured in
both the public and private sectors in the capacities of educator,
expert witness and trainer.
Richard is the President of ATA Associates and a Certified Safety
Professional. He teaches graduate courses in safety engineering
and accident investigation at the University of Houston, Clear Lake.
Sweatt is a Technical Associate with ATA and a retired 22 year veteran
of the Houston Police Department. Mr. Sweatt worked extensively
in the Hit and Run Accident Detail and Accident Investigation Division
and is a licensed private investigator in the state of Texas.
Larson, former manager of the production department at ATA, is currently
working as a freelance computer consultant, programmer and web page
designer. Mr. Larson developed the CD-ROM which accompanies the
Handbook is available May 1999. Call Lawyers and Judges Publishing
Company at (800) 209-7109 for more information.
Expands Test Capabilities
sure that most of our long time clients are aware of our test capabilities
and experience. The list includes, for example:
- Boat performance and handling,
- Automobile and truck crashes,
- Automobile and truck braking,
- Trailer under ride guards,
- Automobile braking systems performance,
- Automobile electrical systems,
- Seat belts,
- Seats, and
- Consumer products from power saws to toilets
however, we took a step toward larger scale laboratory testing when
we designed and had constructed two new pieces of equipment to serve
as test beds for our Houston Technology Center.
first is a 10 foot by 5 foot rigid table for conducting structural
tests. The table weighs 3800 pounds and has a top made from a single
sheet of 1 inch steel plate. The table provides a stable base on
which to mount articles to be tested so that variations in data
due to attachment structure flexing are greatly reduced and our
data is more scientifically accurate.
second, and more recent acquisition is a flying bridge lifting frame
designed to allow us to lift a vehicle and put it in unusual positions.
The fixture operating envelope will support positions in 360 degrees
of roll and yaw and plus or minus 35 degrees of longitudinal pitch
. Greater pitch angles up to 55 degrees can be achieved with supplemental
stabilizing devices. This allows us to:
- Test seat belt performance and determine precise lock trip points
for seat belt actuators in a true 3-dimensional environment.
- Determine other vehicle system performance such as fuel system
shut-off switches in adverse situations.
- Study occupant kinematics by performing occupant movement and
position analysis in actual unusual position situations to determine
seat belt support limits and characteristics, body movement and
roof crush clearance in rollover situations.
- Determine vehicle weight and balance within certain parameters
(we are working to refine this.
- Perform more detailed vehicle inspections with vehicles in post
- Improve the quality, accuracy and perspective of photography of
the underside of vehicles.
device is unique to ATA and expands our test capabilities well beyond
what other accident reconstruction firms are doing to test the validity
of accident causation hypotheses.
addition of these two new tools to support our capabilities adds
significantly to the range of services we can provide our clients
and experts and stays with our philosophy of high technology approaches
to the scientific analysis of accidents.
Asked Questions About On - Board Diagnostics
Environmental Protection Agency has regulations in place establishing
requirements for On-Board Diagnostic (OBD) systems on light duty
vehicles, light-duty trucks as well as heavy trucks beginning with
the 1994 model year. The purpose of the OBD system is to assure
proper emission control system operation for the vehicle's lifetime
by monitoring emission-related components and system operation for
deterioration and malfunction.
is an OBD system and how does it work?
engines in today's vehicles are largely electronically controlled.
Sensors and actuators sense the operation of specific components
(e.g., the oxygen sensor, ABS) and actuate others to maintain optimal
engine control. An on-board computer, known sometimes as a "power
train control module" or an "engine control unit,"
controls all of these systems. With proper software, the on-board
computer is capable of monitoring all of the sensors and actuators
to determine whether they are working as intended. It can detect
a malfunction or deterioration of the various sensors and actuators,
usually well before the driver becomes aware of the problem through
a loss in vehicle performance. The sensors and actuators, along
with the diagnostic software in the on-board computer, make up what
is called the On-Board Diagnostic (OBD) system.
the OBD system retain malfunction codes post accident?
and no. Most vehicle manufacturers used the early OBD-1 system,
dated 1985-1996. This early system is not capable of retaining codes
if power has been cut off. Some vehicle manufacturers, however,
have had the second generation of OBD systems in use. This generation
is called OBD-2. With each new year vehicle manufacturers are installing
better faster systems. For example, a 1997 GM with the OBD-2 system
will be limited in the amount of retrievable data compared with
the 1999 GM. The OBD-2 system will retain malfunction codes as long
as they have not been cleared. If, for example, there was a code
41 in the computer and the battery was destroyed during the accident
there is a very good chance the code would be recoverable. If, to
use another example, emergency crews had to cut a main wire harness
(door) the chances of recoverable codes lessens. This information
has to be assessed on a case by case basis.
ATA Associates, we use the Mastertech Global 2 for collecting and
reading OBD data. We are very pleased with the Mastertech's performance
and are excited about using this data in and for accident reconstruction.
GM Recorded Automotive Crash Event Data
Motors (GM) airbag-equipped production cars have, since 1974, recorded
airbag status and crash severity data for impacts that cause a deployment.
The data-recording feature utilizes fuses to indicate when a deployment
command was given and stores the approximate time the vehicle has
been operated with the warning lamp illuminated.
1990, a more complex Diagnostic and Energy Reserve Module (DERM)
was introduced with the added capability to record closure times
for both the arming and discrimination sensors, as well as any fault
codes present at the time of deployment.
the 1994 model year GM vehicles, GM replaced the multiple electromechanical
switches previously used for crash sensing with a combination of
a single solid state analog accelerometer and a computer algorithm
integrated into a Sensing and Diagnostic Module (SDM). The SDM also
computes and stores the change in longitudinal vehicle velocity
?(V) during the impact to provide an estimate of crash severity.
selected 1999 model-year and 2000-year GM vehicles, the capability
to record vehicle systems status data for a few seconds prior to
an impact has been added. Vehicle speed, engine RPM, throttle position,
and brake switch on/off status are recorded for the five seconds
preceding a deployment or near-deployment event. It is reported
that almost all GM vehicles will add that capability over the next
GM uses a proprietary Event Data Retrieval Unit (EDRU) that interfaces
with a standard Tech 1 scan tool to download through the vehicle
diagnostic connector. The data is displayed in a hexadecimal format.
The data is viewed by General Motors as protected and requires their
direct involvement to be analyzed.
make the EDRU data available to interested researchers, GM is developing
software and interfacing cables allowing the data to be downloaded
to commonly used laptop computers. Data useful to researchers (such
as ?V, seatbelt use, pre-impact data, etc.) will be stored and displayed
in a standard format using engineering units, while data requiring
expert knowledge to interpret will continue to be stored in a hexadecimal
format. The kits and software are expected to be available during
the second quarter of 2000.
has purchased the equipment, and is waiting for software to be released.
Call ATA to understand further how this information can be of use
The Technology of Crash Data Retrieval
the mid 1990's the majority of GM vehicles have been equipped with
SDMs (Sensing and Diagnostic Modules). These modules record and
save crash data related to abnormal operating conditions and air
bag deployment. The gathering of this data has become a specialized
field that aids accident investigators and reconstructionists.
first step in any vehicle crash data recovery is looking at the
vehicle to determine:
Did the airbags deploy?
- What systems/computers are on board?
- Where is the SDM or Ford's EDR (Event Data Recorder)?
- Can you recover availab1e data from the vehicle's systems?
this sounds relatively simple, locating and gaining access to the
crash data recorder, event data recorder, ABS computer, or any other
system is about two-thirds of the job.
can I expect to see in the vehicle data?
year vehicle manufacturers have increased their capability to collect
data, and monitor systems. Today, General Motors' products are leading
the way in vehicle crash data systems and in the way it is recovered.
Collecting such items as:
Vehicle speed 5 seconds before impact.
- Engine speed 5 seconds before impact.
- Brake status 5 seconds before impact.
- Throttle position 5 seconds before impact .
- State of driver's seat belt switch (on/off).
- Passenger's airbag enabled/disabled - (on/off).
- SIR warning lamp status- (on/off).
- Time from vehicle impact to time of airbag deploy.
- Ignition cycle count at event time and investigation.
- Max. ?V for near deployment ?V vs. Time for frontal airbag deployment.
- Time from vehicle impact to time of max. ?V.
- Time between near deployment and deployment events if within 5
are three types of files stored in the vehicles' SDM, also known
as, the Black Box. The first file, in most cases, is called the
Near Deployment File. This file opens when the vehicle has a severe
event that "wakes up" the sensing algorithm but not severe
to deploy the air bag(s). It contains pre-crash and crash data.
SDM can store only one near deployment event. This event can be
overwritten by an event that has a greater SDM recorded velocity
change, or after the ignition has been cycled 250 times.
second type of file is a deployment event. It also contains pre-crash
and crash data. The SDM can store up to two different deployment
events, if they occur within a five seconds of one another. The
first will be stored in the deployment file, the event that deployed
the air bag(s), and the second deployment event will be stored in
the near deployment file.
third file in the SDM is called the hexadecimal data. This information
is not shown on a typical download, though contained in the hexadecimal
data, is information concerning times between algorithm enable (wakeup)
and actual deployment of the air bag. This is data can only be interpreted
by manufacturers at this time.
is important to note that deployment events can not be overwritten,
changed, or cleared from the SDM. Once the vehicle's airbag(s) have
deployed, the SDM must be replaced. Note, with Crash Data Recorders,
vehicle battery loss will not affect the recovery of data.
Why-do manufacturers collect this data?
are approximately 18,000 tow-away crashes in the United States everyday.
This is real time free data. With the average cost of a crash test
running between $25K-30K, it makes good business sense to collect
this information when possible. The California Air Resources Board
(CARB) mandated in the early 1980's, that vehicle manufacturers
begin to monitor emissions. With this requirement, the computer
became a valuable tool for monitoring various related systems. With
each passing year, they have gone from the most simple engine controls
to highly sophisticated crash data recording systems, such as General
Motors' SDM and Ford's EDR.
vehicles can tell you a great deal of valuable information, and
in some cases it might be all you have to determine what transpired.
urges investigators and experts to look for valuable scientific
information early in the case process.
Mike Ennor has been in the automotive industry for over twenty (20)
years. He has been trained in Crash Data Retrieval by the Vectronics
Corporation and is among the few certified technicians in the country.
Business of Testing
Associates is a unique organization dedicated to supporting all
types of product testing and evaluation. Although our core business
is accident reconstruction, we have a qualified staff of engineers
and safety experts that can investigate any type of failure analysis
on just about any object. CEO and owner Robert “Bob”
Swint has put together a team of investigators that take pride in
their ability to produce thorough testing protocol. Recently, The
Expert ran a ten (10) part series called Testing, written by the
president of ATA, Barry Richard. This series is part of the extensive
guidelines that governs all the testing done at our facility.
testing capabilities are endless. We have a fully equipped laboratory
with state-of-the-art microscopic viewing equipment. Also, the technology
center, located in Houston, Texas, is equipped to handle any type
of road vehicle, watercraft, or small aircraft. The video and imaging
equipment used by the ATA staff is professional quality that produces
professional comprehensive reports.
Failure analysis is a crucial part of any type of accident investigation.
Consumer products experience many types of part failures that require
personnel specialized in different types of investigative principles.
ATA has access to some of the most qualified chemists, metallurgists,
and material science experts. We also employ, on staff, aeronautical,
mechanical, and electrical engineers and safety professionals. The
techniques used by our staff and consultants adhere to published
In addition to on site testing, The ATA rapid response team can
be dispatched to any location to perform tests, collect data, and
gather evidence. All testing protocol in the field provides the
same high standards of professionalism that can be achieved in the
most difficult of situations. On-site testing, performed immediately
after an accident, can often be the difference between finding a
cause or not. Crucial evidence and changing environmental conditions
degrade an accident site over time. Quickly introducing qualified
experts into a scene can eliminate costly recreations.
technical nature of quality testing should always be the very first
priority of any investigative team. ATA Associates has assembled
this team and has provided them with the very latest technology
to produce infallible results.
interactive informational CD is available by request. It outlines
the many capabilities of the ATA testing team and describes the
many options available. Please Contact ATA Associates at (281) 480-9847
or visit our website at www.ataassociates.com.
Up – The Brake Analysis
equipped with spring brakes are approximately 98 percent of all
off and on highway trucks. Manually measuring the stroke length
on these brakes can be a time consuming job. There is also the chance
of different interpretations when reading a manual scale in confined
areas. It is now possible to test five (5) pairs of brake stroke
length at once, in a minimal amount of time.
Brake Analyst is a testing device designed to determine slack adjuster
travel on vehicles equipped with S-cam air brakes. It can also determine
if there is excessive wear in the s-cam bushings, broken brake shoe
return springs, broken parking brake chamber springs, and broken
brake chamber return springs.
On a normal class 8 tractor trailer, as seen on today’s highways,
the tractor trailer is equipped with ten separate brakes, one located
at each wheel. The normal adjustment of the slack adjuster is in
the 1 to 1.5 inch range. The re-adjustment point is at 2 inches
for most brakes.
Brake Analyst measures the slack adjuster travel. It accomplishes
this by a purpose built string potentiometer that is attached to
the brake chamber push-rod by a small pair of locking pliers. The
cable from the string potentiometer is magnetically attached to
the face of the brake chamber. A secondary pressure transducer records
air pressure being supplied to the service brake system electrical
cables are routed from the equipment to the control panel. The cables
connect to a laptop computer through a PCM-CIA card. The information
is then fed from the remote sensors into the data acquisition software
that analyzes the information and presents it in a graphical and
tabular form on the computer screen.
Recap and Update
GM’s model year 1989, some form of crash data has been recorded
by the vehicle’s onboard computers (EDR - event data recorder).
By March of 2000, private sector consulting reconstructionists were
given access to the vehicle’s computer via a tool called the
Crash Data Retrieval Kit produced by Vetronix Corporation in cooperation
with General Motors and recently Ford Motor Corporation. Generally,
the older the vehicle is, the more limited the crash data available.
Until 1994, the computer that stored crash information would give
delta-v (change in velocity during a crash) postimpact data, but
no pre-impact data. No information regarding braking or throttle
is available for older model cars. As time passes, more and more
information is stored in the computer that is accessed by the CDR.
Today, most GM vehicles offer five seconds of pre-crash information
about speed, throttle position, brake position (on/off), seatbelt
use for both driver and front seat passenger, and about 300 ms of
post crash data which captures delta-v over time in 10 ms increments.
None of the Ford computers capture pre-crash data; however, post-crash
data is more extensive than GM vehicle computers. Like GM, Ford
computers also indicate seatbelt use.
The number of GM and Ford vehicle models available for download
continue to grow. In the not too distant future, accident reconstructionists
can expect to gather such information as seat position, cruise control
status, ABS braking status, Stabilitrak indication, steering angle,
yaw rate, lateral acceleration, tire pressure, traction control,
door locked/unlocked, PDOF (principal direction of force), etc.
Also promised to become available to the public soon is Toyota model
vehicle data. Heavy Trucking Crash Data Like passenger and light
trucks, tractor engines such as Detroit, Cummins, Caterpillar, and
International have data that potentially can be retrieved after
a crash. The accident reconstruction community has access to this
data, but at a much higher cost than the Vetronix kit. There is
no “universal” kit like Vetronix in the heavy truck
world. One must purchase individual decoders from each manufacturer.
The information from heavy trucks is potentially large. I say potentially
due to the fact that the settings for recording the information
may be changed. Also, the data may be erased and the computers may
be re-used, unlike in passenger vehicles. Some of the information
available, depending on the manufacturer of the engine, includes
vehicle speed, engine RPM, throttle position, brake application,
clutch use, cruise control status, and time duration of up to 120
seconds. Other computers may be found on heavy trucks that record
data such as date, time and odometer readings.
Actions - Past, Present & Future
1997, the National Transportation Safety Board (NTSB) and Jet Propulsion
Laboratory (JPL) issued recommendations to NHTSA (National Highway
Transportation Safety Administration) that they should pursue manufacturer
installed sensor data during their crash testing programs. In November
1999, the NTSB issued recommendations for NHTSA to mandate installation
of EDRs (electronic data recorders) on motor coaches and school
buses and gave specific requirements for the data collection and
survivability of the devices. An EDR is an electronic device that
detects a crash and records certain information for several seconds
of time before, during and after a crash. For instance, an EDR may
record pre-crash data, such as impact speed, forces on the vehicle
during the crash, safety belt use and air bag performance and allow
activation of an automatic collision notification to emergency medical
of the approximately 200 million light vehicles in the U.S., NHTSA
estimates that 15 percent of these vehicles are equipped with EDRs
that can be read, and that between 65 and 90 percent of new light
vehicle models will be equipped with EDRs.
1997, NHTSA’s EDR-related effort has been multi faceted. In
2000, NHTSA purchased EDR data retrieval tools for all its investigation
teams, including Special Crash Investigations (SCI), National Automotive
Sampling System - Crashworthiness Data System (NASS-CDS), and Crash
Injury Research and Engineering Network (CIREN). Recently, NHTSA
modified its crash data bases to capture EDR data. As of mid 2002,
NHTSA had investigated about 300 crashes where EDRs were read.
June (2004), NHTSA proposed standard requirements for EDRs that
manufacturers choose to install in light vehicles. The proposed
rule would not require the installation of EDRs.
is proposing, beginning in September 2008, to: (1) require that
the EDRs voluntarily installed in light vehicles record a minimum
set of specified data elements useful for crash investigations;
(2) specify requirements for that data; (3) increase the survivability
of the EDRs and their data by requiring that they function during
and after front, side and rear crash tests; (4) require vehicle
manufacturers to make publicly available information that would
enable crash investigators to retrieve data from the EDR; and (5)
require vehicle manufacturers to include a brief, standardized statement
in the owner’s manual indicating that the vehicle is equipped
with an EDR and describing the purposes of EDRs. NHTSA will accept
comments on this notice of proposed rulemaking for the next 60 days.
Written comments concerning it should be sent to the DOT Docket
Facility, Attn: Docket No. NHTSA 2004-18029, Room PL-401, 400 Seventh
St., S.W., Washington, D.C., 20590-0001, or faxed to (202) 493-2251.
The notice also will be available for viewing on the NHTSA website:
Quick Response Teams have the capability to secure complete, accurate
and prompt collection of site evidence. Our experienced accident
survey teams are ready to travel anywhere in the country within
hours. They know what to look for, what evidence to preserve, and
how to collect and record evidence using photography, video-graphy
and state-of-the-art site mapping technology.
of Quick Response:
Preservation of Scene
Collection of Evidence
Document Key Witness Information
response services include:
Black Box Download
DOT Level V Inspections
Cargo and Loading
Site Survey Measurements
Secure Accident Debris
Tire and Gouge Marks
utilizing Quick Response capabilities is supplied to ATA’s
reconstructionists, case managers and graphics department, providing
clients with seamless, integrated litigation support.
Smart companies, big and small, have a plan that anticipates events
such as accidents. For motor carrier companies, it is especially
important to set policy in order to be prepared for traffic accidents
involving their trucks. Quick Response is an action plan for what
needs to be done both before and after an accident occurs. This
plan would answer questions such as:
When and who does our driver call if he gets into an accident?
• What company personnel should go to the scene?
• What do they need to do when they get there?
• What if the police report is wrong?
• Are our driver qualifications records up to date?
• Have we kept our vehicle maintenance records up to date?
• What is our company’s safety policy? The list goes
accident reconstruction experts, we are interested in the protection
of evidence. Because evidence deteriorates rapidly, it is important
to gather as much information as possible as early as possible.
Accident scene photography and videography is the fastest way to
get the most evidence recorded. Using proper techniques for taking
still photographs ensures that the scene is well documented. Without
a good understanding of the scene evidence, it may be difficult
to properly understand the accident.
Associates’ experienced professionals will take the time to
discuss the issues addressing emergency response planning and evidence
gathering techniques. Just give us a call.
in Accident Reconstruction
from a Detroit Diesel heavy truck engine can be quite extensive.
The complete report is on the order of 40 pages. Of main interests
to accident reconstructionists are the data contained in the “Last
Stop Record,” the two “Hard Brake Records,” and
three diagnostic records. But how is that data related to an accident?
There is no label in the printout that will say, “impact occurred
here” or “the vehicle traveled so many feet prior to
impact,” etc. In fact, the data can be misleading when it
comes to the reported speeds.
In order to relate the data to the accident scene, careful study
of the data and understanding of the anomalies that can occur in
the data must be understood. In the example chart, the time when
impact occurs is not 0:00 seconds as one may think. Time equals
0:00 is when final rest occurs. The system for recording a hard
brake record is usually set at a point, which will typically trigger
when a deceleration rate of 7 mph/sec is achieved. From the chart,
one can determine that impact occurs at -0:07 seconds.
Looking down the vehicle speed column, notice the speed is reported
at 42 mph at minus 14 seconds and 5.0 mph at minus 13 seconds. This
is not physically possible. One of many reasons for this could be
due to the vehicle yawing (the tires are rotating at a different
rate than the vehicle’s overall speed). Another reason for
such an anomaly is the sensor picking up the ABS braking, which
locks the wheel up to two times per second, thereby fooling the
sensor that monitors vehicle speed. Notice the engine speed dropped
from 875 to 117 rpm. This is more likely than not, a correct reading.
Also notice the throttle percentage which drops to zero as the brakes
are applied. One must be aware that in the case of brake application,
a “Yes” is recorded even if the brakes are just lightly
When the above data is examined and understood, vehicle positions
can be plotted on a scale diagram with tire mark evidence, at each
time step in order to build the story of what happened on the road.
ATA Testing Supports Expert Testimony
Rulings by the U.S. Supreme Court in the 1990's raised the standards for expert testimony. Prior to those rulings, anyone with knowledge of a subject greater than that of the average person was usually regarded as an expert on the subject and could testify based upon experience. That changed with the Court's ruling in the case of Daubert v. Merrell Dow Pharmaceuticals, Inc. in 1993.
The Daubert ruling established factors judges were obliged to consider in determining the admissibility of testimony from scientists. Among those factors was whether the testimony was based on theory alone, or if it was also supported by the results of testing that had been conducted using methods accepted by the scientific community. A ruling in Kuhmo Tire v. Carmichael in 1999 extended the applicability of the Daubert standards to the testimony of engineers and other technical experts.
In showing a preference for testimony based on testing over testimony based solely upon theory, the Daubert and Kuhmo rulings effectively made testing a necessary foundation for much expert testimony. Following the Court's lead, ATA Associates, which had always offered testing as part of its services, made testing a principle focus of the company's efforts. In the years since Daubert and Kuhmo, ATA has become well known for providing the personnel, expertise, equipment, and facilities needed to conduct tests in a variety of technical areas. An abbreviated discussion of some of ATA's testing capabilities follows.
ATA's testing experience includes dramatic full-scale re-enactments of automobile collisions and rollovers and numerous recreational boating mishaps resulting from steering system malfunctions. ATA has also tested the stability and braking performance of a variety of motor vehicles using standard government and industry test protocols.
ATA has tested the stability of tow vehicle/travel trailer combinations at highway speeds; the dynamics of roller coaster cars; and heavy truck behavior following a steer axle tire blowout. ATA has measured the inertial loads experienced by riders on energetic amusement park rides and the inertial forces routinely experienced by passengers on public transportation buses and trains.
In less dramatic but equally important testing, ATA has measured the visibility of stationary and moving vehicles under various night-time illumination conditions; the effectiveness of confined space ventilation in mitigating carbon monoxide hazards; the forces exerted by garage door openers in various operating situations; and the normal and anomalous cycling of electric water heater control circuits.
As a part of its services, ATA documents test results through written reports and appropriate electronic data and photos or video recordings. In conducting tests, ATA typically follows previously established testing protocols such as may be found in Federal Motor Vehicle Specifications. However, in unusual circumstances where no established peer-reviewed testing protocol exists, as happened in tests that used sandbags to model passenger ejection from an amusement park ride, ATA will prepare an appropriate written protocol to document the test method in detail, so the test may be repeated independently.
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