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GM/Ford ATD Verification
and Inventory Management System
A comprehensive PC-network based solution for verification
and inventory management of Anthropomorphic Test Devices
(Crash Test Dummies) was developed for both Ford Motor
Company and General Motors. This solution involves seamless
integration of DIAdem with Visual C++, ASP and Oracle.
DIAdem™ Crash routines handled all data analysis
and plot generation aspects of the application. Routines
written in the supported VBS language, comply with NHTSA,
SAE and ECE regulations.
The application provides a complete genealogy of how
the ATD’s were built up for the test. Real time
status was made available as the ATD’s were built.
Typically between 100 and 250 transducers are integrated
into the ATD for a full vehicle crash. The system collects
the response of each transducer and compares it to corridors
determined by regulatory institutions and the data put
into a detailed report that is automatically generated.
The system was architected to be data driven which permits
convenient addition of new routines or modification of
existing routines. The system allows users to run verification
tests on several test stands that are, in turn, connected
to a database server storing ATD test and part related
information. A web-based interface is used to conveniently
view reports and status of the inventory as well as producing
new report based on multiple automotive regulatory and
development standards.
Anthropomorphic Test Devices (ATDs) or crash test dummies
are an integral part to running automotive safety tests.
ATDs require periodic dynamic verification and certification
tests to ensure they are responding as designed prior
to use in a vehicle crash test. In safety test laboratories,
ATD certification has to be completed efficiently and
reliably. For high volume safety testing, a PC based software
package was required to conduct and manage ATD certification
tests efficiently.
This paper outlines a modular application that performs
the following functions: conducting ATD verification tests,
processing test data, generating certification reports,
and managing dummy inventories and scheduling. The application
seamlessly integrates off-the-shelf software with visual
C++, ASP, and Oracle.
INTRODUCTION
The ATD certification lab operates as a service provider
to the Safety Laboratories by delivering customized ATD
configurations based on engineer vehicle crash test requests.
ATD labs are responsible for certifying that ATDs delivered
to the crash tests meet industry and government verification
standards. The system solution to effectively accomplish
the ATD certification process was designed to be modular
in functionality so as to meet the requirements of different
laboratories.
The entire system is broken down into two main software/hardware
components - 1) A thick client application used by technical
operators in a quasi-configurable production-like environment
to effectively execute the individual ATD verification
tests with instantaneous pass/fail results, and 2) A thin
client application capable of generating web based executive
level reports for monitoring the efficiencies and everyday
operations of the ATD labs. The two applications are linked
in the back-end by a common database configuration that
allows efficient communications about individual tests
so as to create comprehensive tracking reports both from
a real time and historical viewpoint.
The modular system was designed to accommodate different
components for future upgrades that would give minimum
ripple effect on the existing software interface. The
modular components were identified as i) data acquisition/data
input, ii) data analysis algorithms, iii) graphical reporting
and certification results, iv) database and related platform
independencies, v) web-based reporting utilities.
ATD types, verification test parameters, and the associated
analysis algorithms are usually defined in government
and industry test procedures, and are thus rarely modified.
However, the application has to allow for the occasional
change to the verification test corridors or algorithms
as well as the addition of a newly developed ATD type.
ATD CERTIFICATION
Certification includes inspection of ATD components and
the collection of verification tests of various part assemblies.
Verification tests are the individual dynamic tests used
to verify the dynamic mechanical responses of certain
key ATD parts. ATDs are designed to mimic the human response
in crash tests, thus certain parts need to be checked
with a known energy input to verify their performance.
ATD part assemblies may be directionally tested depending
on whether a crash test involves frontal impact or side
impact. Examples of individual verification tests are:
head drops, neck pendulum tests (flexion and extension),
thorax pendulum impacts, torso flexion tests, hip range
of motion tests, and knee pendulum impacts. A typical
verification test involves the following steps:
1. Mount part assembly to be tested to appropriate fixture.
2. Setup data acquisition equipment and acquire data.
3. Analyze data: Calculate various parameters from measurements
and compare against pre-defined limits (corridors). Test
passes if all parameters are within corridors.
4. Generate summary report and plots.
5. Update information into database.
ATD TYPES
ATDs come in various shapes and sizes to mimic the humans.
For example, the 'CRABI-6' ATD represents a 6-month old
infant, whereas a 'Hybrid III 95th %' ATD represents a
large male adult. Other types of ATDs generally fall in
between the two. The proposed application can manage an
unlimited number of dummy types, but a typical laboratory
may need to manage 20 or more different dummy types. Some
ATD laboratories may also categorize their ATD population
based on their usage in crash tests. For example, some
individual dummies may be used with no instrumentation
just to simulate occupant ballast during a crash test.
Other instrumented dummies may be used exclusively for
government certification tests, and others may be used
for non-certification crash tests. The usage of the dummy
may dictate the level of instrumentation and the types
and frequency of verification tests performed. The proposed
application needs to manage not only the ATD type but
it usage category as well.
ATD CERTIFICATION APPLICATION To realize the core
functionality of the ATD Certification Application, it
would be helpful to understand the 'life cycle of an ATD'.
Figure 1 and Figure 2 below show the usage flow diagram
of an ATD. The process outlined is only an example and
not necessarily exactly followed by all ATD certification
labs.
APPLICATION FRAMEWORK
Figure 3 below shows the different modular components
of the application. The primary test executive (thick
client) is written in Microsoft's Visual C++ (VC++). All
test conditions, business rules, test object definitions
and test results are stored in a database. National Instruments'
DIAdem is used as the analysis engine. Reports are stored
electronically in Adobe's Portable Document Format (PDF).
The thick client has the following main features:
1. Setup Configuration
2. Pre-Test Procedures · Changing ATD Category
· Editing Corridor Standards
· Associating ATD Type to Corridor
· Viewing Current Work Log
3. Running Tests
4. Post-Test Operations
· Current Part Trending
· Reviewing Test Data
5. Tracking ATDs, and
6. Managing ATDs and their components.
ATD lab personnel access status reports on ATDs from anywhere
in their LAN via an ASP-based thin client component. All
information is pulled off the same database accessed by
the thick-client component. Data integrity is preserved
as information is only read from the database. Types of
reports available with the thin client:
1. ATD Entity Status Reports
2. ATD Usage Statistics Reports
3. Certification Reports
4. ATD Crash Test Reports
5. Inventory Management Reports, and
6. Log of Completed Verification Tests.
The following sections provide more detail on each of
the thick and thin client components.
THICK CLIENT
Setup Configuration
This module is used to set up the main application run-time
parameters. It is also used to set the location of the
default ATD directory, log files and type of tests to
be done. This module also has the login and logoff sub
items
Pre-Test Procedures
This module is used for setting up the environment prior
to testing.
Changing ATD Category
This window is accessed when the user wishes to change
the usage category of specific ATDs.
Editing Corridor Standards
This feature is used to edit the pass/no pass criteria
(corridors) for verification tests.
Associating ATD Tests to Corridor
ATD labs use different regulatory criteria for verification
tests depending on the requirements of the crash test:
NHTSA - Final Rule, NHTSA - NPRM, European, SAE, custom,
etc. For example, if a verification test for a particular
ATD Type is to be checked for European standards compliance,
the authorized user would use then use this feature to
update the settings.
Viewing Current Work Log
This feature allows ATD lab personnel to get a quick look
into pending verification tests for certifying different
types of ATDs. This feature also displays passed and failed
verification tests.
Running Tests
This module is used for running verification tests. It
is also used for re-processing raw data. This is the main
and most-often used module of the thick client. The module
is user-friendly in the sense that it drives the user
to perform tasks in a particular order. When this GUI
launches, only the 'ATD Type' control and 'Cancel' are
enabled.
When the user selects an ATD type, the ATD number box
gets populated and enabled with a list of those ATDs that
belong to the selected ATD type and have pending verification
tests. When user selects a particular ATD number, tests
that are pending for that ATD are shown in 'Test Type',
and this control is enabled. Upon selecting a test, the
'Sub Test' box is populated and enabled, if applicable.
Once an appropriate sub-test selection is made, the user
is permitted to either 'Review Last Test' or 'Run Test'.
If the user enters an existing raw data file, then the
user has the ability of processing tests rather than performing
a complete run including data acquisition.
Post Test Operations
This module is used for post test operations like current
part trending and reviewing test data.
Current Part Trending
This feature allows ATD lab personnel to review the performance
of ATD parts. In this module, when the user selects a
particular ATD part, results of all past verification
tests using that part are displayed. This allows the user
to predict whether a part is likely to pass during the
next verification test.
Reviewing Test Data
This feature allows ATD lab personnel to review past verification
tests. Only authorized users can change the pass/fail
status of a test; and when doing so, they are required
to enter appropriate reasons.
Tracking ATDs
This module is used by ATD lab personnel to enter the
status of an ATD. Based on the usage flow diagram above,
the ATD can be in one of the following states:
· In the storage vault
· Being built (prepared for the crash test)
· In a crash test
· Being inspected (following the crash test), and
· In the ATD lab, undergoing certification
Managing ATDs and Their Components
From time to time, ATD labs may purchase new ATDs, change
parts on ATDs, or send ATDs out on loan. This module is
used to keep track of such activities. The module also
has a component inventory management feature that allows
users to set flags when the stock of ATD components goes
below a user-selected minimum and alert them to order
a user-selected number of spares.
THIN CLIENT APPLICATION
ATD Entity Status Reports
ATD entity status reports are used to track individual
ATDs. Reports may be filtered by ATD category, location,
status or type.
ATD Usage Statistics Reports
These reports are used to determine the percentage utilization
of different ATDs for a selected date range.
Certification Reports
These reports are used to list all certifications for
crash testing. Certification reports are available for
individual ATDs. A list of certification reports can also
be generated by entering a date range.
ATD Crash Test Reports
These reports provide information about ATDs used in crash
testing. A report may be generated on the basis of a selected
date range or an individual ATD. Another type of crash
test report that may be generated lists all ATDs assigned
to a particular crash test.
Upon selecting a particular ATD and a date range, users
can also generate a report of verification tests run on
that ATD.
Inventory Management Reports
These reports are used to track ATD component information.
Log of Completed Verification Tests
This report permits users to review all verification tests
run in the ATD lab during a particular time span.
CONCLUSION
In conclusion, we have described an application that was
created to help ATD labs certify, manage, and deliver
ATDs for crash testing using an efficient and traceable
methodology. The system is capable of integrating into
the IT backplane of different organizations. It was developed
at a high level of specification to allow for modularity
in data acquisition equipment, evolution of ATD types
and test algorithms, and integration with different database
platforms. Reports and associated lower level testing
details can all be accessed by authorized users via a
web-based application for monitors to view both executive
level summaries and individual test results in an easily
portable format. In summary the above described ATD application
and testing methodology can effectively help high-volume
ATD labs deliver certified ATDs in an efficient and reliable
manner.
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