Active Ankle Foot Orthotic Tester

Stephen Rugg

Ankle foot orthotics are used by individuals who have foot drop syndrome

Foot drop syndrome is the inability to flex your foot up while walking

Background

Source (4)

Christopher Sullivan did research on terrain detection to try and improve ankle foot orthotics

Currently 2 MSD teams are designing active ankle foot orthotics to implement his terrain detection technology

Background

Source (1)

Source (2)

Customer Need # Importance* DescriptionCN1 1 Adjusted for different sized orthoticsCN2 1 Support the active ankle foot orthoticCN3 1 Move along the path a human leg follows while walkingCN4 1 Physically similar to the action of someone's foot who has foot dropCN5 1 Have foot impact the surfaceCN6 1 Easily adjust the settings of the leg motion.CN7 1 Last for 3 years of testingCN8 1 Be able to adjust to a flat, inclined, and declined surfaceCN9 1 Able to move the entire device

CN10 1 Have diognostic capabilitiesCN11 1 Output and display the critical parametersCN12 2 Be able to adjust the walking speedCN13 2 User interface is easy to useCN15 3 Aesthetically pleasing

Customer NeedsDeliverable: Testing mechanism that will accurately mimic the motions a leg makes while walking

Potential Concepts

Motion of a Leg

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1-50

-40

-30

-20

-10

0

10

20

30

40Angle of Lower Leg Rotation Throughout Level Walking Cycle (Adult)

Ang

le (

degr

ees)

Fraction of Walking Cycle

Normal

Extra Slow

SlowMedium

Fast

0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 10.5

1

1.5

2Different Walking Paths from IR Perspective

Period

Vol

tage

(V

)

Level Walking

Down RampUp Ramp

Budget

4 Mechanical Engineers◦ Structural Design◦ LabView Programming◦ Matlab Programming◦ Control System Design◦ Vibrations◦ GD&T

Staffing

2 Electrical Engineers◦ Control Systems◦ Signal Processing◦ Motor Selection◦ Data Collection

1. Gordon KE, Sawicki GS, Ferris DP. Mechanical performance of artificial pneumatic muscles to power an ankle-foot orthosis. Journal of Biomechanics 2006;39(10):1832-1841.

2. http://www.freemanmfg.com/product_info.php?products_id=424&osCsid=7a2e25fe5bc3acab82b7901458b59053

3. Sullivan, Christopher. Design of a Terrain Detection System for Foot Drop. RIT Master’s Thesis. 2012

4. http://www.ctoplp.com/products.html

References