Mechanical & Materials Engineering, Department of


First Advisor

Dr. Carl Nelson

Date of this Version

Fall 10-19-2017


Ashish Shinde (2017) "Cam-Based Pose-Independent Counterweighting for Partial Body-Weight Support in Rehabilitation," University of Nebraska-Lincoln


A Theis 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: December, 2017

Copyright (c) 2017 Ashish Shinde


This thesis presents the design and testing of a body weight support system for gait training in a two-dimensional workspace. Extension of the system to a three-dimensional workspace is not within the scope of this thesis.

Gait dysfunctions are changes in normal walking patterns, often related to a disease or abnormality in different areas of the body. There are numerous body weight support (BWS) systems present in the market which are applied to rehabilitation scenarios in mobility recovery like in gait training. But most of these BWE systems are costly and generally are stationary devices. A major drawback of such devices is the lack of degrees of freedom for free ambulation. While some multidirectional body weight support systems do exist, these devices are equipped with sensors and control systems which increase the cost of the product.

In this thesis, we introduce a new partial body-weight support system for, and apply this to, a rehabilitation scenario in mobility recovery. The idea behind the research is the development of a low-cost weight-offload system which is easy to operate, flexible in its installation footprint, and requires little to no electromechanical input. We propose a cable-based body-weight support system which allows the user to move in a two-dimensional workspace with a uniform supporting force throughout that workspace. This is achieved by coupling the cable displacements to the counterweight displacements using mechanical programming via cams. There will be two identical sets of cams, gear boxes, and counterweights to support uniform force on the payload. The system functionality is demonstrated in a prototype embodiment and tested in the lab.

Advisor: Carl Nelson