John Paul Fallon
Auto-Adjustable Dynamic Ankle-Foot Orthosis
August 2024 – Present·Sanders Lab · UW Bioengineering·Ongoing

Auto-Adjustable Dynamic Ankle-Foot Orthosis

An instrumented, motor-driven ankle-foot orthosis that automatically adjusts its stiffness to match changing activity demands, eliminating the need for users to own separate devices for high-intensity and everyday walking.

BiomechanicsGait AnalysisHuman Subjects ResearchData AnalysisMedical DeviceRehabilitation EngineeringMechanical TestingOrthotics

Overview

The Problem

People with lower-limb disability who rely on dynamic ankle-foot orthoses typically need two separate devices: a stiffer one for high-intensity activity and a more compliant one for everyday community ambulation. This adds cost, inconvenience, and limits their ability to respond to varied terrain and activity demands.

The Solution

A motor-driven adjustable strut on the posterior of the orthosis modulates stiffness in real time. Users can adjust manually via a phone app, or engage an automatic mode that interprets embedded biomechanical sensor data to select the appropriate stiffness without user input.

Key Outcomes

  • Motor-driven adjustable stiffness strut design completed and validated through gait simulator testing
  • Human subjects trials on able-bodied participants completed; relationships between sensed variables and optimal strut settings characterized
  • Clinical trials completed on people with lower-limb disability, including a multi-day take-home study outside the lab

My Role

Research Engineer II
(Fabrication, Human Subjects Testing & Data Analysis)

Impact & Results

The project has progressed from mechanical validation and gait simulator testing through able-bodied human subjects trials and into clinical testing on people with lower-limb disability, including a multi-day take-home study outside the lab. Findings are being written up for publication. If the approach proves out, it provides a validated path toward a single, adaptive orthosis that replaces the two-device paradigm current DAFO users must navigate.

Device Validation

Validated through gait simulator testing and able-bodied human subjects trials, with clinical trials completed on people with lower-limb disability

Data Collection

Gait trials completed; sensor-stiffness relationships characterized across participants and activity conditions

Manuscript

Primary research paper in preparation, documenting findings from the human subjects study

Key Takeaways

  • Designing and executing IRB-approved human subjects gait studies for wearable medical devices
  • Processing and interpreting biomechanical sensor data in the context of clinical gait outcomes
  • Navigating the gap between lab prototype performance and the requirements of consistent clinical deployment
  • Contributing to scientific writing on an active research project

Skills Developed

BiomechanicsGait AnalysisHuman Subjects ResearchData AnalysisMedical Device DevelopmentRehabilitation EngineeringMechanical TestingScientific Writing

Interested in working together?