french institute of science and technology for transport ... - Ifsttar

3_APPLICATION OF RESEARCH FINDINGS, TIES WITH INDUSTRY AND EXPERT APPRAISALS
A major French manufacturer asked IFSTTAR’s Experimental
Testing Unit (UNEX) to perform two tasks: to design “biorealistic”
qualification protocols for body armour and to
specify scientifically-based performance criteria.
The method developed by UNEX was original in that
it consisted of testing the body armour on crash
test dummies fi tted with special sensors in body
positions frequently used during law enforcement
actuvutues.
The dummies were fitted with protection then impacted
at various points with various levels of energy
by impactor heads that simulate the most common
weapons: baseball bats, axes and picks.
The criteria for evaluating the armour were based on fracture
criteria obtained from biomechanical studies in the areas of
motor vehicles and rail passenger transport.
UNEX’s work has led AFNOR to set up a working group (GP3.1)
in order to develop a standard.
This working group consists of users, public sector purchasers,
manufacturers, experts and doctors. UNEX is active as a
scientific expert and in drafting the standard.
This standard will provide a reference for public sector purchasers
when issuing calls for tenders..
@ CONTACT
patrick.joffrin@ifsttar.fr
Optical metrology test sets
The BOCCA and BIRD simulators
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Numerical simulation considerably reduces the time and
resources that are required to validate new detection
systems based on videocameras and image processing
software.
To perform this validation it is necessary to characterize
the videocameras used and the objects that are created in the
simulation with a high degree of precision. To this end, the
LEMCO unit has built two optical metrology test sets, BOCCA
and BIRD.
BOCCA (Optical test set for characterizing videocameras) is
based on image analysis of an optical structure that has been
calibrated under controlled lighting. BIRD (BIdrectional Reflectance
Distribution) measures the distributions that characterize
how materials reflect light under different angles of
illumination.
The equivalent of BOCCA has been created in the Pro-Sivic
simulation software in order to calibrate the simulated sensors
that have been developed for this software. The simulation
model could thus replicate the characterized cameras remarkably
faithfully. BOCCA has mainly been used to determine the
camera’s physical and optical defects which makes it possible
to simulate detection systems.
The nature of the environment in which the sensor is placed
is also of prime importance. Its second test set has allowed
LEMCO to build up a large number of measurements of different
types of material that make up the sensor’s environment.
A paper given at the Transport Research Arena 2012 on
BOCCA won first prize in the Safety category.
@ CONTACT
melanie.grapinet@ifsttar.fr
The BOCCA
metrological test set.
ifsttar French institute of science and technology for transport, development and networks