P15001: Soft Ankle-Foot Orthotic


Top Row: Geni Giannotti, Megan Ehrhart, Noah Schadt, Tyler Leichtenberger Bottom Row: Jared Green, Adam Podolec

Top Row: Geni Giannotti, Megan Ehrhart, Noah Schadt, Tyler Leichtenberger Bottom Row: Jared Green, Adam Podolec

Project Name
Active Ankle Foot Orthotic: Untethered Flexible Exoskeleton Air Muscle
Project Number
Project Family
Biomedical Systems and Technologies Track
Start Term
2141 (Fall 2014)
End Term
2145 (Spring 2015)
Faculty Guide
Mr. Edward Hanzlik, echeee@rit.edu
Primary Customer
Dr. Elizabeth DeBartolo, eademe@rit.edu

Project Overview

Our senior design project is an active ankle-foot orthotic (AFO). This is an assistive walking device that is utilized by individuals with Foot Drop condition. Current AFO’s are bulky, rigid, and disrupt the user’s natural gait by providing assistance at all times, regardless of need.

Device Overview:
An active AFO will provide users with assistance only during appropriate times in the gait cycle through the use of an air muscle. This timing will be determined using a Heelstrike sensor to measure gait and a distance sensor to distinguish terrain. The air muscle will be filled with compressed air from an air tank; this will make the AFO untethered, a feature that has not been completed by a senior design team at RIT.

This device is not a replacement for medical treatment- it is simply a device to assist someone with walking.

Customer Requirements: How the System Addresses the Need:
Hold foot up when stepping forward

Increased Dorsiflexion Mobility with Air Muscle

Last for full day without recharging

Muscle can provide correct number of flexes for target demographic

Fit into clients existing shoe

Adds only 0.12 inches to clients foot

Adapt to different terrain

Manual switch added to provide desired support up stairs

Utilizes a McKibben muscle

Muscle used and designed for needed deflection and number of flexes

The device must be soft and flexible rather than rigid

Device is machine washable and more aesthetically pleasing than previous project

System Design
The design of the AFO was split into two pieces, an upper component and a lower component.
The lower component is comprised of the soft orthotic, the McKibben muscle with lower and upper attachments, the lower component housing with the sensor PCB board and IR sensor, the heel sensor, and the toe sensor.
The upper component consists of a small backpack that contains a compressed air tank with a regulator, a solenoid valve, a printed circuit board (PCB), and batteries. A pressurized air hose, power cable, and signal wiring are tethered together in a mesh sleeve and routed from the backpack to the lower component.


Home Planning & Execution Problem Definition Systems Design Subsystems Design Detailed Design Gate Review
Build Preparation Build & Test Integrate & Assemble System Validation System Verification Final Review