Ankle Rotator Design

Summary

As part of a research project in collaboration with the Shirley Ryan Abilitylab I designed a prototype clinical device for measuring ankle stiffness. Many people that suffer ankle injuries develop chronic ankle instability which leads to more injuries. This research proposes that ankle stability is directly dependent on ankle stiffness. The design work I did on this project will lead to a device that can accurately quantize ankle stiffness in order to provide better insight for ankle treatment.

Proposal

All the work here was done to contribute to the research of Dr. Daniel Ludvig of the Shirley Ryan Abilitylab. His research is focused on investigating neuromuscular motor control of the limbs. The long term goal is to develop individualized treatment plans that will eliminate chronic ankle instability. As a first step the central hypothesis is that the main factor for ankle stability is the mechanical stiffness of the joint.

My specific contribution to his research is a design for a prototype clinical device that will actuate a patients ankle in two/three degrees of freedom. The device should actuate oscillations on the ankle in the frontal plane and in the sagittal plane. A stretch goal is for the device to be compliant to patient actuation in the vertical direction to act as a simulated stepping motion. The point of rotation on the device should be at the patient’s ankle. Force and torque measurements will be gathered through a 6 degree of freedom load cell on the device in order to characterize ankle stiffness and stability.

The proposed specifications for the device are shown in the table below. !!!! SPECS TABLE HERE !!!!