A new medical device monitors human body functions
wirelessly in a fit-and-press assembly that requires no adhesives or mechanical
Called ViSi Mobile, the wireless device is currently under
development by DD Studio in concert with its client and manufacturer Sotera
Wireless Inc. of San Diego, CA. It was unveiled at Canon Communications' MD&M East show in
New York City this week.
Sensors attach to a patient's arm to monitor vital signs,
such as blood pressure and heart rate so that clinicians can remotely monitor
patients' information. The system also includes an eight-port charging station.
One of the benefits of the device is the ability to capture continuous blood
pressure measurement for ambulatory patients without the need for frequent cuff
inflation. The system is compatible with standard Windows-based operating
"When Sotera Wireless approached us with this medical-device
design concept, it wanted the look and feel of a small, user-friendly consumer
product, but had a number of specific demands. The device had to be chemical-resistant,
durable, easy to clean and submersible. We weren't sure the design was
possible," says Michael Swartz, growth strategist, DD Studio.
The device's lens, housing, printed circuit board assembly
and connectors are made with Eastman Tritan co-polyester MX711. The
cold-swaging capability of Tritan allows for fit-and-press
assembly of the device, offering a tight, smooth, continuous fit between parts.
The co-polyester also provides resistance to chemicals used
in disinfectants and cleansers without cracking or crazing. The material also exceeded
To protect the device from water and fluids found in the
hospital environment, it had to meet IPX7 requirements (International
Protection Rating) of withstanding water submersion for 60 minutes at a depth
of 1 meter. DD Studio relied on compatibility samples and testing results from PolyOne
to select GLS Versaflex OM 3060 TPE, which adheres to the co-polyester
substrate to seal the device housing, including speaker port and microphone,
from water seepage and protect internal electronics.
The housing components use a two-shot injection molding
process, combining Versaflex TPE with the Eastman co-polyester substrate. In
addition, insert-molded Versaflex is used to hold cables in place on the four
device connectors. This material provides firm adhesion to the cable assembly
and strain relief properties.
DD Studio and the product development team worked with
Phillips Plastics Corp. to ensure the manufacturability of the design. Phillips Plastics Corp. of Hudson,
WI took the designs DD Studio created and conducted a detailed DFM exercise and
created market-entry prototype tooling.
Clinical testing on the device, which will be used in
hospitals and homes, is now being conducted.
Wireless, which changed its name from Triage Wireless in 2009, recently secured
$10.75 million of a $15 million round of venture funding to develop its
wireless monitoring technology. Investors in the company are Qualcomm Ventures,
Intel Capital, Sanderling Ventures and Apposite Capital.
technology for monitoring all of the vital signs will be a valuable safety net
for seniors and people suffering from chronic diseases who want to live independently,
but be connected to their doctor if there is a problem," says Gary West,
founder and chairman of the West Wireless Health Institute (WWHI) in La Jolla,