Reusable Casting
Apparatus
for Custom Orthotics
Group Members:
Ryan Cook, Keegan Compton,
Michelle Sauer
Advisors:
Matt Moore - Sole Supports Inc.
Dr. Paul King - Vanderbilt University
Sole Supports Inc.
• MASS Position Theory
– Maximum Arch Subtalar Supination
• Full Contact Orthotic
Red- Neutral Position
Gray- MASS Position
Casting Technique
• Foam Casting Box
– Captures foot in three dimensions
• Foot Introduced Sequentially
– Heel to Forefoot
– Mimics gait cycle
• Floor Used as Plane of Reference
– Heel, fifth and first metatarsal head
brought down to floor
• Semi-weight bearing
– Maintains maximum arch supination
Problem
• Sole Supports Inc. pays over $500,000
annually to ship foam casting boxes to
their clients
• Foam casting box is not reusable and
poses a threat to the environment
Previous Work
• 2006 Vanderbilt Senior
Design Project
– Low Cost Scanner
• Sole Supports Inc. has tried
other materials and casting
techniques
– Want fresh eyes to look at
the problem
Project Objectives
• Find a Reusable Material
– Maintain Sole Supports Inc.
Casting Method
– Cost Effective
– Environmentally Friendly
– Easily returns to original
shape
Potential Solutions
•
•
•
•
•
Mud-like substances
Modeling Clay
Play-Doh
Pinart 3-D Impressions
Gels (ceramic powders and
solvents)
• Mattress Material (Memory
Foam)
• Temperature Dependent
Materials
Idea #1: Pin-Art 3D
• Advantages:
– Easily reusable
– Instant reset: flip and
go again!
– Utilized by other
orthotic companies!
(neutral)
Problems with Pin-Art 3D
• Only utilizes the z-direction
• Resolution requirements would mean
very small pins
• Imaging
– Holes between pins would lead to problems
– Solution would require shortening the gaps
– Time Cost
Idea #2: Shape Memory Alloy
• Metal that returns to its original shape when
acted upon by temperature
• Advantages
– Easily returns to original shape
• Problems
– Expensive
• (Custom Made)
– Temperature Range
• (400-500 ºC)
Idea #3: Latex/Memory Foam
• Using memory foam to capture the footprint and
latex as the exterior barrier, a check valve will
allow air to escape as pressure is added to the
top, but not allow it to come back in.
• Pros:
– Hooking it back to an air hose makes it easily
resetable and reusable
• Cons:
– Three point test for coplanar accuracy may not be as
easy to take with latex exterior
• Memory Foam (beige) would have an airtight latex
barrier (dotted line) so that the air from the foam would
only escape through the check valve (black hole). The
dimensions planned currently are the same as the
dimensions of the current pink foam used (36.5 cm x 15
cm x 6 cm).
Memory Foam Testing
• Initial tests to measure certain properties
– Retraction time
– Temperature
• Hot
– Heating lamp, hot plate, heating pad
• Cold
– Cold pack, freezer, ice bucket
–
–
–
–
Applied Force & Time of Applied Force
Shape of Material
Addition of Liquid
Foam Density
• May not even need latex exterior if the properties of the
foam allow us to safely interact with it above glass
transition temperature
Memory Foam Testing
• Time of Applied Force
and Retraction Time
40
Retraction Time
(seconds)
– Using Wooden Blocks
Block and Book Weights
30
Pink
20
Green
10
Yellow
0
0 10 20 30 40 50 60 70
Depression Tim e (seconds)
Memory Foam Testing
– Using a Foot
Ryan's Foot and Body Weight
Retraction Time
(seconds)
• Time of Applied Force
and Retraction Time
80
60
Pink
40
Green
20
Yellow
0
0 10 20 30 40 50 60 70
Depression Tim e (seconds)
Memory Foam Testing
• Temperature and Retraction Time
Foam Type
Green
Green
Yellow
Yellow
Pink
Pink
72°F
47°F
72°F
49°F
72°F
NA
Reaction Time (sec)
(Depression Time 30 (sec))
9
6.6
6.5
11
31
NA
Reaction Time (sec)
(Depression Time 60 (sec))
9
3
8
8.8
33
NA
Temperature
Completed Work
• Met with Matt Moore at Sole Supports Inc.
• Toured Sole Supports Inc.
• Received instruction in Sole Supports Inc.
casting techniques
• Learned limitations of current casting
process
• Established goals for project
• NCIIA proposal
More Completed Work
•
•
•
•
Researched Shape Memory Alloys
Researched Pin Art
Researched Memory Foam
Met with Dr. Sung to Discuss
– Biomaterials
– Memory shape polymers
•
•
•
•
•
Researched Material Costs
Ordered Memory Foam
Established Timeline the Rest of the Semester
Performed Memory Foam Testing
Built Scaled Down Prototype
Current Work
•
•
•
•
Memory Foam Testing
Prototype Testing
Setting Dates for Testing at Sole Supports
Developing Website
Future Work
• Build Workable Prototype
• Create Standard for Comparison using
Sole Supports Current Methods
• Test Prototype at Sole Supports