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Laser Scanning
Automated Complex Measuring Process and Increased Accuracy
 The
Company
The company is a global provider of mobile multimedia devices. It makes
products that are unique in the areas of imaging, design and
applications, and uses the most advanced major mobile communications
technologies. The division involved in this project creates the hardware
used for cellular network testing in autos, taxi, and delivery trucks by
collecting network data inside an electronic box.
The Challenge
The company’s TEMS (Telecommunications Management System) Division was
developing a new unit used for cellular network testing which consisted
of a cellular phone placed inside an electronics enclosure and
interfaced with other specially designed electronic components while
maintaining the full functionality of the phone’s connectors. The
problem arose in measuring the phone’s complex, curvy geometry. The
mechanical engineer in charge had been painstakingly measuring the phone
by hand fairly successfully but the process took 3-4 days to complete.
He had to acquire many measurements to make sure they could faithfully
reproduce every part of the irregular and curved shape. The bracketry in
the enclosure needed to hold the cell phone securely, so that it would
neither bounce around nor compress, and accurately match the placement
of battery contacts.
The engineer had heard of laser scanning technology and knew it was a
much faster method for measuring freeform shapes and fine details. He
performed an Internet search and found GKS Inspection Services, a
division of Laser Design, Inc., at the top of the list. He called a few
of the companies returned by the search, but Larry Carlberg, GKS Service
Bureau Manager, responded quickly and quoted the best price for the job.
The Solution
 Carlberg
often performs scanning projects similar to the one proposed by this
company with great success. He commented, “Laser scanning is still
relatively unknown in the field. We hear from people who have a problem
with creating accurate, usable 3D data all the time. They have tried
many routes to solve their problem, including measuring with manual
instruments, and have come to many dead ends. The manufacturer is
usually frustrated and looking for a solution online when they find us.
We show them what we can do on a very truncated timeline which is
appealing since they have already wasted so much time in trying futile
approaches. Customers are ‘tickled’ to experience the results GKS
provides: tremendous cost savings, very fast and accurate scanning.”
With over 25 years
in the business, GKS metrologists have experience with all kinds of
custom projects. 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, eliminating
the problem of missing data on an irregularly shaped surface. The system
measures fine details and captures complex freeform geometry so that the
object can be exactly replicated. Laser scanners quickly measure
articles, picking up tens of thousands of coordinates per second, and
generating huge numbers of data points without the need for templates or
fixtures.
Carlberg explained
to the project engineer the approach he would take to address the issues
of the curved surfaces and the many connector site locations. GKS
maintains several Laser Design scanners, so the appropriate size and
resolution was readily available in house. Carlberg decided to use the
RPS-120 laser probe; it has an accuracy of ± .001 inch, about half the
thickness of a piece of paper, and a high scan density which made the
post-scan modeling task easier.
The cell phone was
mounted on the Aerotech rotary stage on the Laser Design Surveyor
DS-2030 system. Carlberg explained the need for the rotary: “The
rotary stage is used to capture the whole surface of the object, 360°
around. After completing the scan from one view, we rotate the part to
scan areas that were not visible before. Then the Surveyor Scan Control
(SSC) software used in scanning allows the operator to automatically
merge all the scan positions created on the rotary into a single ‘point
cloud’ of data"
The Results
To make the laser scanning results usable straight away, Carlberg knew
that the company’s engineers needed a solid model exported in a
parasolid format. The advantage of the parasolid model is that the
surfaces are knit together with no untrimmed edges that prevent editing
software from redrawing the part. All the surfaces are continuous. “We
deliver a tremendous value to product designers. Our experienced team is
able to send them completely usable data in only 3-4 days,” remarked
Carlberg. In addition to the creation of the parasolid model for the
customer, GKS also provided a method to check the created model against
the point data of the product scanned. This ensures the model is within
acceptable limits for the successful design application.
“The scan turned out well,” said the engineer. “We are using the scan
data on the first design iteration. The process saved us a lot of time
in measuring the phone. The details captured in the laser scan by GKS
are impossible to get with calipers. The measurements obtained from
calipers are close, but not exact. And the time savings translates into
dollar savings for the company.” Using laser scanning reduces variables
and errors, as well as time to market. The accuracies are good for the
application, better than those attainable by manual measurement methods.
Laser scanning by GKS saved the engineers from having to do a second
iteration to get the necessary level of detail for the assembly.
“It is nice to hit it right the first time instead of having to do
iterations that take up to two weeks,” the engineer continued. “The
scanned model saves us time and prevents the possibility of measurement
errors. Clean files allow us to create good assembly drawings and good
drawings create better documentation for our proposal process. At this
stage, the drawing already looks like a phone.”
About GKS
GKS Inspection Services has been a leading provider of dimensional
inspection, 3D laser scanning and terrestrial scanning services for over
25 years. The company’s Plymouth, MI lab (Detroit metro area) is
accredited by the A2LA for Mechanical Testing and Calibration and
features numerous CMMs, vision systems, 3D laser scanners, surface
analyzers and other inspection equipment. GKS also has U.S. offices in
Minneapolis and Seattle and international locations in India, Korea,
China, Taiwan and the Netherlands. The company’s metrologists and
engineers are experienced in the automotive, defense, electronics and
many other manufacturing industries.
More Information
For additional information about how GKS Inspection Services can improve
your manufactured product, save you money and decrease your development
time, call Larry Carlberg at 952-252-3432 or send email to
measure@gks.com
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