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Expert Laser
Scanning Saves Time by Creating Ready-to-use Data in One Iteration
The Company
 The
company produces rugged cases for electronics products such as cell
phones, PDAs, iPods®, and other portable devices made by the leading
manufacturers for the active customer and harsh work environments. The
hard-shell cases provide shock mitigation, water resistance, and dust
and dirt protection, while allowing access to all buttons, dials, ports,
and other device features. Customers
include military personnel, construction workers, police and
firefighters, EMT/healthcare workers, and others whose professions
require extra protection in extreme and hazardous conditions. Business
professionals, technology enthusiasts, frequent travelers, and outdoor
adventurers also appreciate the strong cases that protect their valuable
electronics in every environment.
The Challenge
 In
developing protective cases for large OEM companies’ products, the
company creates an attractive value-added accessory for the end customer
using off-the-shelf technology. Their current project involved
designing a case for a Blackberry® cell phone. However, in order to
design the case, designers needed an accurate CAD model of the device.
The design mechanical engineer heading up the project explains,
“Basically, we needed a 3D model to help create our case for a new
Blackberry® smartphone called the Pearl.”
The challenge in
designing OEM cases is a variation on a theme: making an extremely
accurate case quickly without having finalized CAD data. When the
company’s engineers begin to design a case, the base model may exist
only in CAD and is not yet a physical part. Sometimes the item may be
in the prototype or first-run stage, so the dimensions are not yet hard
and fast. Other times the OEMs are protecting proprietary data and
release only the skin CAD to the designers. All of these situations
make it difficult to create a fully functional case for the product.
According to the project design engineer, “When this type of data has
been used to develop the case model, it takes up to one week of an
engineer’s time to create a usable file with smooth, edited data because
our company is not set up to do this type of work.”
 At
first, the company tried another solution to generate a CAD model. They
used a desktop scanner to make a 3D model, but quickly found that the
scan was of inferior quality. The machine had no built-in logic and no
processing capability, so every wrinkle and bump in the data was
manifest in the physical 3D model. The resulting data file took too
much time to edit and clean up to obtain the quality necessary for case
production.
The preferred
method for initiating the case design process is using a real part
(rather than a CAD file from the OEM) which insures that the scan is
representative of the actual physical device as it is manufactured.
However, if the engineers must wait for a production part, they must be
extremely quick in their response time. Their custom-fitted case must
be released as close to the device product launch as possible. Quick
turnaround is imperative and phenomenal accuracy is essential. Most of
the device’s exteriors are injection molded, but also
 include
assemblies such as connectors, sheet metal, cast parts, stamped, metal,
or machined parts, that add complications to a scanning setup. For
example, spring-loaded buttons cannot be measured with touch probes
because they depress the buttons, thereby destroying the real profile
shape.
The project design
engineer discovered that “it is more cost effective and much faster to
have an actual production part scanned by an expert shop that can
provide us with ready-to-use clean files.” The design team found GKS
Inspection Services, a division of Laser Design, Inc., through a web
search and made first contact with Service Bureau Manager Larry Carlberg
when he realized that the 3D desktop scanner’s results were unusable.
The Solution
The discussion
about scan requirements with Carlberg was short. The project design
engineer emailed photos of the case to GKS with the critical areas
marked. He recalled, “Larry knew just what to do.”
 With
over 25 years in the business, GKS metrologists have experience with all
kinds of projects involving small electronic devices. “Over the years we
have developed an awareness of what needs to be captured for this type
of scan,” Carlberg explained. “This company needed a detailed, extremely
accurate rendering of the device’s exterior skin so they could design a
shell that conformed to the shape with a designated clearance. Their
shell must preserve full functionality of the device, which means that
all the openings for spring-loaded buttons, ports, connectors, the
battery case, and possibly a camera lens and microphone must be in
exactly the right place. They design around the keypad, speaker, and
microphone openings, so having a precise 3D model is essential.
Non-contact laser scanning is perfect for this application because it
does not distort the shape of the spring-loaded buttons and other
delicate features.”
Laser scanning
systems project 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 with holes such as the smartphone. 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.
 To
scan the Pearl device, Carlberg used Laser Design’s Surveyor DS-2020
system with the high accuracy RPS-120 laser probe to insure high density
coordinates. The setup also included an Aerotech rotary stage so that
multiple orientations of Pearl device could be captured quickly and
accurately and merged into a single “point cloud” of data using the
Surveyor Scan Control (SSC) software. The SSC software finds redundant
data points and matches their positions to create a whole 3D model
automatically. GKS’s modeler then created a parasolid 3D model. The
advantage of parasolids is that they are continuous surfaces and have no
untrimmed edges, which prevent software from working with a model.
Carlberg explained, “The resulting files that we sent to the case-making
company were not only extremely accurate, but usable without further
processing, thus saving them precious time to market. They were
thrilled with the results.”
The Results
“The data from GKS
was very high quality, very usable CAD,” the project design engineer
affirmed. “Having GKS perform this laser scan decreased our lead time by
about a week. To create this type of data any other way is labor
intensive if you do not have access to the final line CAD files from the
OEMs. GKS’s files needed no further processing so we were able to start
creating exterior surfaces from them immediately.” Turnaround time was
a mere 3-4 days which included obtaining the purchase order and shipping the part to GKS.
By relying on the
excellent results from GKS, the design engineers were assured of
accurate boundary layers and strategic locations of buttons, ports, and
LEDs, and the geometric size and shape. GKS 3D models are accurate to
within a few thousands of an inch, saving the designers time by not
having to redo projects due to errors in the prototype phase or to do
multiple design iterations. The project engineer commented, “GKS’
scanning service allows us to finish projects more efficiently.
 Since
this scan job was a first step in the development of a totally new
product, the process is still in progress. However, based on his
initial examination of the scan data, the design engineer concludes,
“GKS gave us turnkey results. Larry nailed it on the first scan; he
understood what we were after right away. We have everything we need
in hand with the resulting files. They were beautiful.”
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,
contact GKS Inspection Services at 952-252-3433 or by email
at:
measure@gks.com
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