The senior design poster that my team presented to our adviser and sponsor in Winter 2014.

1. EXISTING OTOSCOPES
Figure 1. The cost of the Welch Allyn otoscope ranges from
$150-$350 (left) while Dr. Mom’s costs approximately $50 (right)
REQUIREMENTS
CONCLUSIONS
Inexpensive - The primary goal of this project is to design
a more affordable otoscope
Self-Contained Operation – The otoscope must be
operated without any external sources of electricity
Appropriate Lighting and Magnification – The
otoscope must provide adequate viewing of the tympanic
membrane so that otitis media can be properly diagnosed
Easily Sanitized - The otoscope must be easy to sanitize
and reuse so all patients may be safely examined
Durability - The long-term reliability of all components of
the otoscope must be considered Our LED otoscope can be used to effectively diagnose
otitis media, is more affordable than otoscopes available on
the market, and fulfills all of the customer requirements.
INTRODUCTION FINAL DESIGN CONCEPTUAL DESIGN
Background:
• Otitis media, also known as an ear infection, affects
11% of the population in some developing countries
• An otoscope is a medical device used to inspect and
diagnose otitis media
Problem Statement:
• Many developing countries have inconsistent power
supplies and insufficient medical funding to utilize and
afford an otoscope
Goal:
• To develop an LED-based, inexpensive, and self-
contained otoscope that can effectively diagnose otitis
media
Inexpensive LED-Based Otoscope
Brooks, Andrew; Chiu, Michael; Winnewisser, Scott
Advisor: Professor David Laiho Sponsor: Dr. Lily Laiho
CRANK-POWERED
MECHANISM
SPECULA
3-LED RING AND LENS
Figure 2. Final design of our otoscope
Figure 6. SolidWorks model of the otoscope
Figure 3. Acrylic LED ring with glass lens
Figure 4. Crank-powered flashlight
Figure 5. Silicone mold (left) and polyurethane plastic specula (right)
• The 3-LED ring and 5x magnification glass lens
provide comparable brightness and viewing to Dr.
Mom’s otoscope
• Manufacturing Process:
• Laser-cut the ring from acrylic plastic
• Utilized a mill to cut angled holes for the LEDs
TEST RESULTS
Impact Resistance:
• Our otoscope frame remained intact after dropping
it ten times from 7 ft. above a concrete floor
Brightness:
• Our otoscope was charged for 15 seconds
• A lux meter was used to measure the brightness for
30 seconds
Visibility:
• Dr. Slishman verified that our otoscope can
adequately view the tympanic membrane
Cost: Table II. Total material cost
Device Brightness Range
Dr. Mom
(1 AA Battery)
580-597 Lux
Our Otoscope
(Crank-Powered)
543-614 Lux
Table I. Brightness Test Results
Component Cost
Crank-Mechanism $6.82
Lens $1.23
LED Ring $0.12
LEDs (3x) $0.66
Resistor $0.03
PVC Head/Body $0.13
Specula $0.07
TOTAL $9.06
The final design incorporates a polyvinyl chloride housing, crank-powered mechanism, LED ring, glass lens, and specula
• The specula allows for direct illumination
of the tympanic membrane
• The specula can easily be removed and
sanitized
• Manufacturing Process:
• Utilized rapid prototyping to create a
silicone mold
• Produced a specula using polyurethane
plastic
• With the crank-powered mechanism, the otoscope
is self-contained and independent of external
electricity
• Sufficient power for inspecting the eardrum
requires only 15 seconds or less of charging
• Manufacturing Process:
• Rewired the flashlight to power the LED ring