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Institution and
Research:
 Brooklyn
College, part of the City University of New York (CUNY), is a well
respected institution of higher education offering over 60 undergraduate
and graduate majors in the humanities, sciences, performing arts, social
sciences, education, and the professions. With over 16,000 students
from more than 100 nations worldwide, Brooklyn College is as ethnically
diverse as the city it serves. Faculty members are active researchers
in their fields as well as teachers and mentors for students.
 The
Department of Anthropology and Archaeology, led by Dr. Arthur Bankoff,
an archaeologist with long experience in the Near East, is developing a
new research area in the study of ancient cylinder seal impressions and
clay tablets bearing cuneiform inscriptions, an early form of writing.
Dr. Alfred Rosenberger, a biological anthropologist in the Department
whose main area of research is the evolution of nonhuman primates, has
used the Laser Design Surveyor three-dimensional laser scanning system
in the past to scan primate fossils and precisely document their shapes.
Using the LDI laser scanning system to scan ancient tablets seemed like
a natural transfer of the technology and good use of departmental
resources to delve into the etiology of the cuneiform artifacts. Bankoff
and Rosenberger, partnering with Dr. Rudi Mayr, who has spent his
professional lifetime studying cuneiform tablets, applied for and
received a grant from the National Endowment for the Humanities in 2006
for this project called “Cuneiform Forensics – 3D digital analysis of
cuneiform tablet production.”
Project:
 The
pilot research project investigated the feasibility of using laser
scanning and 3D quantification and analysis of the cuneiform signs on a
series of tablets to provide a new, high-tech way of studying and
learning from ancient artifacts. As the team
member with the most experience in using the LDI 3D laser digitizing
system, Dr. Rosenberger became the project co-director in charge of
scanning the clay tablets, managing the technical aspects of the
scanning operation, and quality control of the 3D models, as well as the
database development and outreach elements. Students assisted in
performing scans in accordance with the Department’s practice of
encouraging interdisciplinary studies and hands-on research in the lab
and in the field.
The project sought to
give archaeologists another tool for understanding and postulating ideas
about a culture and people that lived about 4,000 years ago in
Mesopotamia, in the region of modern-day Iraq and Iran, by using the 3D
laser scanner to create authentic, accurate digital models of the
cuneiform tablet artifacts. The artifacts were scanned with the LDI
laser scanning system and a digital model was created. The models were
measured so that each cuneiform sign was accurately described by digital
data.
 The
ultimate goal is to develop a battery of robust techniques and methods
that will make “cuneiform forensics” possible. This involves analyzing
the shapes of the signs as if they were handwriting and developing a
database of the precise 3D measurements to study meanings of the
physical elements as well as the linguistic and language elements.
Detailed analysis of the cuneiform tablet properties could give
researchers some idea about literary abilities of the people of the
communities that used this form of writing. We know that a class of
professional scribes existed, but is there reason to believe that even
people without extensive scribal training could read and write? How
many people in the society were able to write? Were writing skills
based on class distinctions? Were only the rich, priestly, or scholarly
able to write, or was a larger segment of the population involved?
In the field of
Mesopotamian archaeology and cuneiform studies, this project is the
first time that laser-based shape-capture techniques have been combined
with digital tools for capturing three-dimensional micro measurements
and statistical tools for studying shape. It is one of the first times
that cuneiform tablets have been studied with an anthropological
approach, explicitly looking at the tablets as artifacts carrying clues
to their own culturally determined production and use, and bearing
information beyond what was specifically written on them.
The dataset used was
a sample of 30 tablets, which will eventually be deposited in the large
collection belonging to the Department of Near Eastern Studies at
Cornell University. These well-preserved tablets were written within two
months of one another, possibly by the same scribe. A homogenous sample
of tablets from the same time and place provides a better base from
which to make scientific inferences and postulate anthropological
theories about the population. Recognizable patterns and stylus
techniques are likely to emerge.
Method:
Scanning, modeling,
and analyzing the data from the cuneiform artifacts took about a year to
complete. A final report will be presented to the National Endowment for
the Humanities and an interdisciplinary panel of experts for their
evaluation. Based on positive feedback from the reviewers, the Brooklyn
College Anthropology Department plans to follow up and garner subsequent
NEH funding for further studies.
The scanning process
brings a dead writing technique back to life. Cuneiform is written in
the form of symbols and signs inscribed into soft clay with a stylus in
specific patterns, much as our modern languages are handwritten today.
Interestingly, no styli have been found, which leads to the conclusion
that they must have been made of biodegradable material, such as wood or
reed.
Because of their
small size, each cuneiform tablet, an approximately 1½” handmade
equilateral triangles of clay, required only one or two scan passes to
create an accurate, detailed 3D model. Each tablet contained a few lines
written in the Akkadian language, including a date by month and day. A
seal "closes" the envelope, much like what a modern notary public does
to prevent alterations of the contents of a message.
 The
details captured from the surface of the tablets are used for analysis
on many different levels. The data record the precise characteristics
of each wedge (length, breadth, depth, and volume), and the spatial
relationships between and among wedges (average horizontal distance from
an adjacent stroke and distance between whole symbols derived from
calculating spatial centers of the symbols).
“Scanning the tablet
in three dimensions gives us information that we cannot get from the
language itself,” commented Dr. Rosenberger. “Not only does each sign
have a meaning, but each may carry the personal touch of the person who
made them. How that person held the stylus, how deeply he or she
pressed it into the wet clay, placed the ends of lines and arranged the
crossing points of the tic-tac-toe like symbols - all of this can be
analyzed. Precise 3D measurements will allow us to create a database to
study the meanings of things other than the linguistic symbols, such as
how the symbols were made and possibly by whom. The laser scanning
provides us with a way to collect the inherently three-dimensional data
to perform the equivalent of a forensic analysis of conventional
two-dimensional handwriting.”
Scanning free-form
detailed shapes, especially undercuts and miniscule changes in surface
texture like those on the cuneiform tablets, is ideally suited to
non-contact laser scanning. Because the laser scanning system projects
a line of laser light onto surfaces while cameras continuously
triangulate the changing distance and profile of the laser line as it
sweeps along, the problems of missing data on an irregularly shaped
surface is eliminated. This laser line moves back and forth over the
part until the complete surface is captured. The system measures fine
details and complex free-form geometry so that the object can be exactly
replicated digitally. Laser scanners measure articles quickly, picking
up tens of thousands of points per second, and generate huge numbers of
data points without the need for templates or fixtures.
Originally purchased by Brooklyn College
in January of 2004, the affordable Laser Design RE-1208 desktop scanning
system is equipped with an RPS-120 laser probe, LDI’s highest accuracy
probe for scanning small to medium-size objects with fine details. The
RPS probe’s accuracy is excellent, +/-.00025” (.00635 mm) per point with
averaging, generating very dense point cloud coordinates (.001”, .025
mm). The laser probe features a Class II rating with a visible beam,
for safe and easy-to-see operation and a long standoff to prevent
crashes during dynamic part scanning, which is very important when
inexperienced student operators perform the scans.
LDI’s proprietary software, Surveyor Scan
Control (SSC),
controls the scanning motions, manages the laser probe settings, and
contains advanced automation features. The rotary stage allows the
system to automatically scan parts from all orientations and then easily
merge the data into a common coordinate system.
After scanning the object, the scan data
was processed further with Geomagic Raindrop software to quickly make
surface models, in essence reverse engineering the tablets digitally.
The freeware software, “Landmark,” designed by computer scientists and
anthropologists as a measuring tool specifically for anthropological
studies, provided easy point-and-click coordinate identification and
measuring capabilities, as well as spatial dimension definition for
working with the scan data in this project.
 Scans
of the tablets were edited to isolate individual signs for easier
landmarking. The measured sample was composed of the data derived from
identical points taken on the same sign on each tablet. Isolation of
the signs allowed for exact placement of measurement points, using both
the tablet surface and the reverse side of the scan.
Results:
Once measurements
were made digitally on all the samples, analyses were run to determine
characteristic elements of the cuneiform writing, the seals, and the
tablets themselves. With this information, the archaeologists of
Brooklyn College’s Department of Anthropology and Archaeology eventually
hope to extrapolate their findings to tablets from other areas and time
periods, as well as other ancient artifacts, and develop a method of
“forensic analysis” for studying many types of objects. The final
report for the project to the NEH will be the basis for more research
and funding for applications of the non-contact 3D laser scanning
techniques that they have performed with Laser Design’s Surveyor
system.
In the future, the
Department of Anthropology and Archaeology plans to use the 3D scan data
to produce stereolithographic models of cuneiform tablets in various
sizes for use in the classroom. Thus, the scanning process will help
bring a dead writing technique back to life for students learning about
cuneiform from exact replicas.
The sample files form
the beginning of an archive of scanned Near Eastern tablets. Further
research will add other assemblages to this archive, allowing others
access to the data and providing more comparative data for “handwriting”
analysis. The Department will make available to the general public
manipulable 3D graphic models of the tablets on a website dedicated to
this project.
“The laser scanning
technology of the Laser Design 3D scanning system opened up a whole new
dimension in what we can explore, dimensions that we wouldn’t have
thought of before,” commented Dr. Rosenberger. “It allows us to look at
our artifacts in different ways and extract new kinds of meaning. Since
the non-contact laser scanning method does not touch or damage the rare
tablets, we can gather immense amounts of information from them in the
present while preserving their integrity for researchers to study in the
future.”
About Laser
Design:
Laser Design, Inc. has been the leading
supplier of ultra-precise, 3D laser scanning systems and services
for over 20 years. Used for capturing the 3D
shape of objects with complex geometries and free-form surfaces, Laser
Design’s Surveyor line of automated and portable scanning systems are
ideal for 3D scanning applications involving inspection and reverse
engineering of complex shaped plastic and metal parts. The company’s
patented laser line-probe technology dramatically reduces scanning time
by collecting data substantially faster and more accurately than
conventional metrology technologies. Laser Design integrates
Geomagic software with its laser scanners to provide complete solutions
for reverse engineering and inspection applications.
Headquartered in
Minneapolis, the company also has Regional Technical Services and
Support Centers in Seattle and Detroit, and distributors throughout
Europe, Asia, and North America. Laser Design also operates GKS
Inspection Services (www.GKS.com),
an in-house service bureau division offering complete 3D scanning,
reverse engineering, and dimensional inspection services.
For further
information, contact Rick Passek, by phone (952-252-3412), fax
(952-884-9653), via email to
sales@laserdesign.com, or visit Laser Design’s web site at
http://www.laserdesign.com. |
