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Laser Scanning Creates Online Virtual Museum for Researchers Worldwide
Institution:
Marshall University is a state-supported
university with 2-year and 4-year undergraduate and
graduate programs located in Huntington, WV. It is
accredited as an institution of higher learning by
the Commission on Institutions of Higher Education
of the North Central Association of Colleges and
Schools.
Dr. Suzanne Strait of the Biological
Sciences Department specializes in vertebrate
paleontology. She has been creating research
projects with funding from the National Science
Foundation (NSF) for over 10 years.
Project:
Dr. Strait first became interested in scanning
technologies while writing her thesis on the
comparative anatomy of fossil mammal teeth. She
used an electron microscope to make 2D scans of her
specimens. This rudimentary scanning method took
enormous amounts of time and did not provide the
three-dimensional data necessary for researchers to
manipulate the objects and see the 3D shapes or take
realistic measurements for comparisons and study.
 In order to
advance her research, Dr. Strait kept abreast of the
new scanning technologies being developed in
industry. When she heard about 3D laser scanning,
she knew it would be ideal for her purposes: faster,
more accurate, easier to do, non-contact, and in
3D. She envisioned creating a website as an online
virtual museum for researchers to view fossils in 3D
and download functions so they could manipulate,
measure, and compare them. “Fossils are a rare
commodity, each one unique and housed in widely
dispersed museums around the world, so access is
very limited,” noted Dr. Strait. Having an online
museum that displayed lifelike, virtual images would
be a valuable research tool for paleontologists and
other scientists, giving them access to many objects
without having to travel to remote locations.
Dr.
Strait’s groundbreaking project, first funded by the
NSF in 1997, allowed
her to research laser scanning technologies and
purchase the Laser Design Surveyor RE-810 3D laser
scanning system in 2000.
Laser Design, Inc., based
in Minneapolis, MN, has been the leading supplier of
ultra-precise, 3D laser scanning systems and
services for over 20 years.
The RE-810 is an affordable desktop 3D scanning
system with the European CE Mark that is well suited
for scanning small, highly-detailed fossils and
artifacts like bones and teeth, and therefore
popular with anthropologists, archeologists, and
paleontologists in museums and universities. The
system scans parts from all orientations and easily
merges the data into a common coordinate system
known as a “3D point cloud”. The rotary stage
automates the scanning process making it even easier
and faster.
 Further
NSF funding (nearing the $2 million mark) for
projects spanning the years 2002 until 2009 has
allowed Dr. Strait to continue building on her
original project using the Laser Design Surveyor
system to scan fossils obtained from North American
dig sites and post them on the interactive virtual
museum website.
The fossils in
question are from the Paleocene-Eocene boundary era,
approximately 55 million years ago, which the most
pronounced period of global warming during the
entire period that mammals dominated the earth. Many
mammals which first migrated to North America at the
beginning of this period dispersed during the warm
interval. This “Paleocene-Eocene Thermal Maximum”
period impacted terrestrial and marine ecosystems
worldwide. The fossil record provides understanding
into the consequences of climatic change on Earth’s
modern plant and animal species and gives us
indicators as to what the effects of our present-day
human induced climate change will be in the future.
 At the outset of
the research project, over 3000 early Eocene mammal
specimens were unearthed in the southeastern Bighorn
Basin of Wyoming. The recovered specimens along
with others borrowed from museums around the world
will be laser scanned and documented in Paleoview3D
(http://paleoview3d.marshall.edu),
the online database/museum. Creating a database of
this type is unique and provides a model for
institutions on how to make their collections easily
accessible and useful to researchers everywhere.
The project also allows students to participate in
the research in a very hands-on way. By learning to
scan and catalog specimens, they are exposed to
modern field methods and high-end, state-of-the-art
technology.
Method:
PaleoView3D is an
interactive 3D model library that will eventually
display over 700 fossil specimens from 20 museums.
So far 37 are available online. Dr. Strait and her
students started scanning fossils in 2000 on the
Laser
Design Surveyor 3D laser scanning system. At the
time of purchase, the system was still running the
original Laser Design proprietary data collecting
and editing software in UNIX. Since the system
“operators” were biology undergraduate students, not
computer scientists, the software was cumbersome and
hard to work with. However, soon thereafter, the
system was updated with the new Surveyor Scan
Control (SSC), the Windows version of the software
with enhanced functionality and ease-of-use, so the
scanning and modeling processes became much easier
for the students to perform. SSC
controls the scanning motions, manages the laser
probe settings, and contains advanced automation
features.
The
Surveyor 3D laser scanning system’s
patented laser probe technology dramatically reduces
scanning time by collecting data significantly
faster and more accurately than with other
technologies. 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 is much like spray painting the part with
points, moving back and forth until the complete
part is captured. The system measures fine details
and captures complex freeform 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 generating
huge numbers of data points without the need for
templates or fixtures.
The Surveyor system’s laser, a high
accuracy RPS-120 probe with a high scan density, is
ideal for small and medium-sized specimens with fine
detail features.
Oftentimes, the fossil
specimens to be scanned were very small; for example
some teeth were only 1-2 mm². “We require excellent
precision to scan such small artifacts. The
resolution level of the probe is very good. It
produces a very dense point cloud of coordinates
(.001”, .025 mm) so our measurement data is very
accurate,” commented Dr. Strait.
The RPS
laser probe features a Class II rating with a
visible beam, for safe and easy-to-see operations
and a long standoff to prevent crashes during
dynamic part scanning, which is very important when
inexperienced student operators are performing the
scans.
Many of the
specimens included in the virtual research museum
are teeth and bone fragments. Dr. Strait continued,
“Isolated elements, such as a tooth or femur, are
easier to scan. Bone groups, such as a jaw bone
with teeth, are more challenging to scan and require
multiple scans to gather enough 3D data to create an
accurate, detailed 3D model. Most of the fossils are
tiny, less than 1 mm, and have lots of undercuts.”
Scanning free-form detailed shapes, however is
non-contact laser scanning’s forte, and the student
operators easily pick up scanning techniques. Since
the objects are relatively small in size, the
scanning process can be completed in less than an
hour even though the specimens must be scanned from
several orientations. After scanning, the data is
merged and edited, then converted into surface
models, or reverse engineered, in
Raindrop Geomagic Studio 7.0,
which takes more time,
usually a few hours, to complete.
Results:
The PaleoView3D database
currently focuses on North American late Paleocene
and early Eocene mammals . Further expansion is
planned to include more species and time periods.
Ideally, every “type” of animal fossil from the
period will be represented in the future, so
researchers can contrast and compare the online
models with other fossils for identification
purposes and further study.
The data
collected by the Laser Design Surveyor system are
extremely detailed. Many of the technical
specifications listed with the specimens come
directly out of the laser scans and the Laser Design
SSC software used to create them. The surface
models are high resolution images that can be viewed
in 3D, magnified and rotated. Simple measurements
(i.e., linear distance, circumference, and arcs) of
each model can be made directly on the web-site with
a basic point-and-click feature. Each image can also
be downloaded as a data file so that more
sophisticated 3D measurements can be made using CAD,
GIS, or 3D measurement software.
The PaleoView 3D
website database is rich in many types of
information regarding the specimens, such as
specimen number in the original museum and pertinent
hyperlinks and reference lists, detailed locality
and age of fossil, skeletal element, descriptive
narrative of the species, and year collected, to
name a few.
The website also
details the technical aspects of the laser scanning,
such as number of scans performed, number of
coordinate data points, exposure or the probe CCDs,
and linear spacing of the scan lines.
“We have made
amazing progress on the PaleoView3D database thus
far. With the remaining two years of project
funding, we will be able to make it a truly useful
tool for researchers all over the world,” concluded
Dr. Strait. “We hope to be a leader in what will be
an explosion of online databases, an innovation
possible because of the advancements in the field 3D
laser scanning found in our Surveyor system from
Laser Design.”
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.
For
further information, contact Rick Passek, by phone (952-252-3412), fax
(952-884-9653), via email to
sales@laserdesign.comm or visit Laser Design’s web site at
http://www.laserdesign.com |
