SOLID-STATE SMART MATERIAL
BASED PROSTHETIC ARM
Advisor: Dr. Onur Bilgen (MAE)
Mechanical Subgroup Members:
● Gordon Clark ● Brad Ketterer
● Megan Guzman ● Mark Levenstein
● Paul Jelenek
● Daniel Park
● Can Karaoz
● Stephanie Vasquez
Electrical Subgroup Members:
● Jared Gongloff ● Michael Pollard
● Brett Lefebvre ● Theodore Teates
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
1
•
•
BACKGROUND
Approximately 6,000 upper extremity amputations per year in the U.S.
30% to 50% of upper limb prosthetic users avoid wearing their prosthetic due to its
weight [1].
•
•
Many current prosthetics are still based on designs from the 1950s [2]
Highly functional prosthetics range anywhere from $3,000 - $30,000, making them
unaffordable for many amputees [3].
•
. . . a modern solution is needed.
References:
[1] Price et al., Smart Mater. Struct. 16, 1401 (2007)
[2] Cupo et al., J. Rehabil. Res. Dev. 35, 431 (1998)
[3] Turner, Disabled World, 2009, <http://www.disabled-world.com/assistivedevices/prostheses/prosthetics-costs.php>.
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
2
OBJECTIVES
Our goal is to develop a lightweight, composite upper limb
prosthesis that utilizes Shape Memory Alloy (SMA) wires for high
force-to-weight actuation.
•
•
•
•
Prototype for trans-humeral amputees
Muscle-like fluid movement
2 DOF (degrees-of-freedom)
No motors, linkages, gears, etc.
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
3
ORGANIZATION
Solid-State Prosthetic Arm
Electrical
Components
Mechanical
Components
1
2
Skeleton
/FEA
3
Composites
& Rapid
Prototyping
4
Smart
Material
Integration
Actuation
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
5
Sensing
Control
Algorithm
4
Bicep
Triceps
Elbow
Plate
Inner Elbow/
SMA Wire
Intersection
SMA Wire
Bundle
Wrist
Forearm
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
Outer Elbow/
SMA Wire
Intersection
5
(1) FINITE-ELEMENT-ANALYSIS MODEL
Location of
Constraints
15 lb Force
• Elbow Joint
Modulus of Elasticity: 198 ksi
Poisson’s Ratio: 0.1
Density: 0.0578 lb/in^3
Max Displacement
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
6
(2) COMPOSITES
Carbon Fiber
Glass Fiber
Weave
1K x 3K 3.5 oz
7725 9 oz
Density
122.8 oz/in3
178.3 oz/in3
Elasticity
195.5 ksi
172.02 ksi
Price/yd
$59.95
$9.65
Benefits
Strength
Layer
Manipulation
Clamp
Material
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
Load
Ruler
Clamp
7
(2) MOLD
3-D printed Male Mold
Upper Arm
Recessed Elbow
Forearm
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
8
(3) SINGLE SMA WIRE TESTING
Load Cell – Computer
Connection
Retrieved
Data To
LabView
Power Supply
Fixed Voltage
(10V)
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
Variable
Voltage
9
(3) SMA ARTIFICIAL MUSCLES
Shoulder
Screw
End Caps
End Cap
SMA/Silicone Muscle
Weld Nut
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
10
(3) SMA RIBBON FABRICATION
Loop configuration for
equal pre-tension
SMA wire wound
from loops to posts
Posts
Liquid
Silicon
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
11
Ribbon prototype
(0.0015 inch
SMA wire)
(3) WIRE FRAMING RIG
Old Frame
Space for
end-caps
New Frame
(longer &
slimmer)
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
12
(4) ACTUATION AND SENSING
4 Strain Gage
circuit connection
(350 OHM SG)
6 MOSFET
Conditioning Circuit
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
13
(5) CONTROLS
• Arduino Mega 2560
• Open/Closed loop manual (button) control
• Optimal progression towards EMG control
Taken from Peerdeman et al., J. Rehabil. Res. Dev. 48, 719 (2011) DOI:10.1682/JRRD.2010.08.0161
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
14
(5) CONTROLS
• Neural Network
• Gradient Descent Algorithm
Desired
Trajectory
creator
NN
controller
Wij = ηei xj − WijT ei
http://www.hindawi.com/journals/cin/2011/289398/fig1/
Plant
T
(1)
𝑇
𝑒𝑖 = 𝐼𝑖 + 𝑊𝑖𝑖𝑇 𝑊𝑦𝑖
𝑒𝑦
(2)
𝑖 = 𝑊𝑖𝑖 𝑖 + 𝑊𝑖𝑥 𝑥
(3)
𝑦 = 𝑊𝑦𝑖 𝑖 + 𝑊𝑦𝑥 𝑥
(4)
Solid state prosthetic senior design team 2013-2014
15
GANTT CHART
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
16
THANK YOU FOR YOUR TIME
QUESTIONS OR COMMENTS?
SOLID STATE PROSTHETIC SENIOR DESIGN TEAM 2013-2014
17