Mechanical & Materials Engineering, Department of


First Advisor

Carl A. Nelson

Date of this Version

Spring 5-2022


Pusnik, Zvonimir (2022). Design of Path Correction for Improved Gait Rehabilitation, MS thesis, University of Nebraska-Lincoln, May 2022.


A THESIS Presented to the Faculty of The Graduate College at the University of Nebraska In Partial Fulfillment of Requirements For the Degree of Master of Science, Major: Mechanical Engineering and Applied Mechanics, Under the Supervision of Professor Carl A. Nelson. Lincoln, Nebraska: May, 2022

Copyright © 2022 Zvonimir Pusnik


Following a serious neurological injury or disease, such as a spinal cord injury or multiple sclerosis, many patients develop impaired gait (the ability to walk). There are many different pieces of equipment to help rehabilitate people with impaired gait, ranging from over ground walking with exoskeletons to treadmills with partial bodyweight support. Since the 1990s and 2000s, elliptical trainers have entered the rehabilitative field as a machine with low impact forces and gait-like motion. This led researchers at Madonna Rehabilitation Hospitals to collaborate with the University of Nebraska-Lincoln to create the Intelligently Controlled Assistive Rehabilitation Elliptical (ICARE).

While the ICARE is currently used in rehabilitating patients, its motion patterns tend to deviate from normal gait at more distal joints. In order to correct these deviations and further improve the ICARE’s performance, a four-bar mechanism was created to attach to the ICARE while assisting a patient in rehabilitative exercise. The kinematic synthesis input for this problem specifically focused on the gait of the right foot centroid. Both traditional kinematic synthesis techniques and modern synthesis software were utilized in the process of creating a solution to this synthesis problem. It was observed that the designed mechanism greatly improved the horizontal and vertical displacements of the foot centroid with milder improvements for the angular displacement.

Advisor: Carl A. Nelson