Design of an Ankle Foot Orthotic - PowerPoint Presentation

Slide1

Design of an Ankle Foot Orthotic

Christopher SullivanSlide2

Outline

What is Foot Drop?

Overview of gait cycle

Different kinds of existing AFOs

Actuator Selection

Timeline

BudgetSlide3

Why do People Need Ankle Foot Orthotics?

Foot Drop

inability to Dorsiflex the foot during the Gait Cycle

Foot Drop is a Symptom associated with:

List conditions from next slide here

Figure

1 http://sports.jrank.org/article_images/sports.jrank.org/dorsiflexion.1.jpgSlide4

Who does Drop Foot Effect?

Foot Drop is a lasting symptom to a variety of neurological conditions.

S

troke

C

erebral Palsy

Multiple SclerosisPolioDirect injury to the Peroneal NerveFigure 2 http://upload.wikimedia.org/wikipedia/commons/9/9d/Gray832.pngSlide5

The Gait Cycle

Over the years the Gait Cycle has been meticulously measured.

Periods

Initial Double-Limb Support

Single-Limb Stance

Second Double-Limb Support

Initial Swing

Mid-Swing

Terminal Swing

Foot Strike

Opposite Toe-Off

Opposite Foot Strike

Toe-Off

Foot Clearance

Tibia Vertical

Foot Strike

Stance

Swing

% of Cycle

0%

62%

100%

 Slide6

2-D kinematics of leg during walking

Svensson W, Holmberg U. Ankle-Foot-Orthosis Control in Inclinations and Stairs. 2008 21-24 Sept. 2008. p 301-306.Slide7

2-D kinematics of leg during walking

θ

P

= Angle of the Pelvis relative to the ground

θ

H

=Angle of the Upper Leg relative to the PelvisθN=Angle of the Lower Leg relative to the Upper Leg

θ

A

= Angle of the Ankle relative to the Lower Leg

BSlide8

2-D kinematics of leg during walking

Free Body Diagram Created

Simple Q

uasistatic Analysis Done

Dynamic Analysis

Still needs to be Done

BSlide9

What is an Ankle Foot Orthotic?

Commercially Available

Hard Plastic AFO

Electrical Stimulation

Recently investigated

i-AFO

Variable Dampening AFO for Inclined SurfacesAFO with Air MusclesPneumatic Power Harvesting AFO

An orthopedic brace meant to repaired lost function in the foot and ankle.Slide10

Hard Plastic AFO

Passive support of the Foot

Molded to fit patient’s leg

Rigidity can cause problems

Prefabricated Ankle-Foot

Orthosis

.

(

n.d.

). Retrieved from ANKLE-FOOT

ORTHOSIS: http

://www.orthomerica.com/products/anklefoot/ankle_foot.htmSlide11

Electrical Stimulation

Bioness

Stimulates the

Peroneal Nerve

Expensive

Unable to use if you have Pacemaker

Heart ConditionsRecent fracture or dislocationperoneal nerve locationSilberstein, N. (2008, November 2).

Foot Drop

. Retrieved from

Pt

Products Online: http://www.ptproductsonline.com/issues/articles/2008-11_02.aspSlide12

Variable Dampening AFO for Inclined Surfaces

Created in 2008 at Halmstad University in Sweden

Uses Magneto Rheological Damper

Very Unique

Too bulky to fit in shoe

The power supply is never specified

Svensson W, Holmberg U. Ankle-Foot-Orthosis Control in Inclinations and Stairs. 2008 21-24 Sept. 2008. p 301-306

.Slide13

i-AFO

Constructed in 2010 at Yamagata University in Japan

Uses Rotary braking system

Untethered

Too bulky to fit in shoe

Kikuchi T, Tanida S,

Otsuki

K, Yasuda T,

Furusho

JYM. Development of third-generation intelligently Controllable ankle-foot orthosis with compact MR fluid brake T2 - Robotics and Automation (ICRA), 2010 IEEE International Conference on. Robotics and Automation (ICRA), 2010 IEEE International Conference on 2010.Slide14

AFO with Air Muscles

Created in 2005 at the University of Michigan

Uses Air Muscles to produce

Plantarflexion

Too bulky to fit in shoe Tethered

to an external air supply

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.Slide15

Pneumatic Power Harvesting AFO

Created in 2009

at University of Illinois at

Urbana-Champaign

Used a simple Pneumatic Linear Actuator

Generated its own powerToo bulky to fit in shoe

Chin R, Hsiao-Wecksler E, Loth E, Kogler G,

Manwaring

S, Tyson S, Shorter K, Gilmer J. A pneumatic power harvesting ankle-foot

orthosis

to prevent foot-drop. Journal of

NeuroEngineering

and Rehabilitation 2009;6(1):1-11.Slide16

Actuator Selection

Gomis-Bellmunt

O, Campanile LF. Actuator Design Analysis. Design Rules for Actuators in Active Mechanical Systems: Springer London; 2010. p 29-78.Slide17

Actuator Selection

Gomis-Bellmunt

O, Campanile LF. Actuator Design Analysis. Design Rules for Actuators in Active Mechanical Systems: Springer London; 2010. p 29-78.Slide18

Actuator Selection

Gomis-Bellmunt

O, Campanile LF. Actuator Design Analysis. Design Rules for Actuators in Active Mechanical Systems: Springer London; 2010. p 29-78.Slide19

Next Steps

Before Design work can truly commence

Interviews must be held

A dynamic model must be created

Proof of concepts prototypesSlide20

Time Line Winter Spring (2010-2011)

Goals

Initial Literature Search Begun

Finish

Literature Search

Finish and present Thesis ProposalModeling of the Foot

Course LoadWinterACTSystem DynamicsRapid PrototypingSpringThermal Fluids Lab 2Intro To BiomaterialsDynamics Of MachinerySystem ModelingComp Imp FEMSlide21

Time Line Summer (2011)

Goals

Co-Op

working on

project

Interviews Finish Modeling the Foot

Proof of Concept prototypes created Systems level designDetailed Design Building AFO StartedWriting ThesisCo-op40 hr/wkSlide22

Time Line Fall (2011)

Goals

Finish

Building AFO

Bench Testing

Writing Thesis

Course LoadControl SystemsSenior Design 1Math 1Slide23

Time Line Winter (2011-2012)

Goals

Finish

Bench Testing

Clinical Testing

Compile WorkWriting Thesis

Submit paper to IMECE or SBCCourse LoadInter. Control SystemsSenior Design 2Math 2Slide24

Time Line Spring (2012)

Goals

Finish

Clinical Testing

Finish Writing Thesis

Thesis Defense

Course LoadAdvanced Control SystemsSlide25

Budget

Part Time Work

10 hr/wk for 3

qtrs

Full Time Summer Co-Op

40 hr/wk

Prototype$1000 for parts and testing suppliesSlide26

Important Mile Stones

Getting Approval to talk to patients

Interviews

Design Reviews

Presentation

Bench TestingClinical Testing ApprovalSlide27

Summary

The goal of this project will be to create an Ankle Foot Orthotic

The difference between our project and any of the mentioned projects, is the way that the problem will be attackedSlide28

Questions?Slide29

References

Silberstein, N. (2008, November 2).

Foot Drop

. Retrieved from

Pt

Products Online: http://www.ptproductsonline.com/issues/articles/2008-11_02.asp

New Device Helps Stroke Patients suffering from 'foot drop'. (2010, September 17). Retrieved from Healthlink: . http://www.nwcn.com/news/health/New-device-helps-stroke-patients-suffering-from-foot-drop-103150749.htmlRoşca, I. C., & Radu, C. (2008, April 24-26 ). On the Design of the Analitycal Ankle – Foot Model . 6th International DAAAM Baltic Conference

.

Sutherland DH,

Olshen

R, Cooper L, Woo SL. The development of mature gait. J Bone Joint

Surg

Am 1980;62(3):336-53.

Whittle MW. Clinical gait analysis: A review. Human Movement Science 1996;15(3):369-387.

Pandy

MG. Models for understanding the dynamics of human walking 1987.

Pandy

MG,

Berme

N. Synthesis of human walking: A planar model for single support. Journal of Biomechanics 1988;21(12):1053-1060.

Vaughan CL, Davis BL, O'Connor JC. Dynamics of human gait. Champaign, Ill.: Human Kinetics Publishers; 1992.

Prefabricated Ankle-Foot Orthoses. (n.d.). Retrieved from ANKLE-FOOT ORTHOSIS: http://www.orthomerica.com/products/anklefoot/ankle_foot.htm

Sohn RH, Park SW, Hwang SH, Ko AR, Lee YH, Lee SH,

Ryu KH, Kim YH. A Potable System for Foot-Drop Correction using Electrical Stimulation.259-260.Contraindications for Use of the NESS L300 Foot Drop System. (2010). Retrieved from Bioness

: http://www.bioness.com/Canada_-_English/Contraindications.phpKikuchi T, Tanida S, Otsuki K, Yasuda T, Furusho

JYM. Development of third-generation intelligently Controllable ankle-foot orthosis with compact MR fluid brake T2 - Robotics and Automation (ICRA), 2010 IEEE International Conference on. Robotics and Automation (ICRA), 2010 IEEE International Conference on 2010.Svensson W, Holmberg U. Ankle-Foot-Orthosis Control in Inclinations and Stairs. 2008 21-24 Sept. 2008. p 301-306.

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.

Chin R, Hsiao-Wecksler E, Loth E, Kogler G, Manwaring

S, Tyson S, Shorter K, Gilmer J. A pneumatic power harvesting ankle-foot orthosis to prevent foot-drop. Journal of NeuroEngineering and Rehabilitation 2009;6(1):1-11.Gomis-Bellmunt O, Campanile LF. Actuator Design Analysis. Design Rules for Actuators in Active Mechanical Systems: Springer London; 2010. p 29-78.Huber, E. J, Fleck, A. N, Ashby, F. M. The Selection of Mechanical Actuators Based on Performance Indices. London, Royaume-uni: Royal Society of London; 1997. 21 p.

Tavakoli M, Marques L, de Almeida AT. A comparison study on Pneumatic Muscles and electrical motors. 2009 22-25 Feb. 2009. p 1590-1594.Tsagarakis N, Caldwell DGY. Improved modeling and assessment of pneumatic muscle actuators T2 - Robotics and Automation, 2000. Proceedings. ICRA '00. IEEE International Conference on. Robotics and Automation, 2000. Proceedings. ICRA '00. IEEE International Conference on 2004.

Sauer P, Kozłowski K, Morita Y,

Ukai H. Ankle Robot for People with Drop Foot – Case Study.443-452.Blaya JA, Herr H. Adaptive control of a variable-impedance ankle-foot orthosis to assist drop-foot gait. IEEE Trans Neural

Syst Rehabil Eng 2004;12(1):24-31.

Chu TT. Biomechanics of ankle-foot orthoses: past, present, and future. Top Stroke Rehabil 2001;7(4):19-28.

Ohata K, Yasui T, Tsuboyama T, Ichihashi N. Effects of an ankle-foot orthosis with oil damper on muscle activity in adults after stroke. Gait Posture. Volume 33. England: 2010 Elsevier B.V; 2011. p 102-7

.