Show simple item record

dc.contributor.authorHerrmann, Christineen_US
dc.description.abstractThe purpose of this investigation is to propose a method for determining resultant joint moments from a Biodex System 3 isokinetic dynamometer. Previous investigations using a dynamometers determined that measured moments from a dynamometer do not equate to the moment applied by the joint. Using Biodex System 3 dimensions and equipment, the proposed method corrects for gravity, acceleration and inertia moments, and relative angular movement between the dynamometer and the joint axis of rotation for the knee and ankle. The current method includes gravitations correction using a 3rd order polyfit method to a 4°/s passive trial, and inclusion of inertial moments from the dynamometer arm and limb segment. A method is also proposed to correct for gravitational moments, acceleration and inertia moments, and distal joint moments while testing the hip.

Previously proposed methods are then compared to the proposed method in isometric and isokinetic exertions. The comparison to a known moment concluded that the results for the isometric exertion are accurate for the proposed method. If the torque measurements from the dynamometer are independent of the velocity, as reported by the manufacturer, the validation of the proposed method for isometric testing holds true for isokinetic as well. The results from isokinetic testing show reasonable results for determining the resultant joint moments.

The proposed method can be simplified for clinical or experimental testing. If inertial and acceleration moments are not of concern, than using the propsed gravitational correction will account for the COM (Center of Mass). No additional measurements of the limb segement and dynamometer attachment are needed. The proposed method is recommended for Biodex System 3 isokinetic dynamometer correction in obtaining resultant joint moments at the knee, ankle, and hip.

dc.publisherVirginia Techen_US
dc.rightsI hereby certify that, if appropriate, I have obtained and attached hereto a written permission statement from the owner(s) of each third party copyrighted matter to be included in my thesis, dissertation, or project report, allowing distribution as specified below. I certify that the version I submitted is the same as that approved by my advisory committee. I hereby grant to Virginia Tech or its agents the non-exclusive license to archive and make accessible, under the conditions specified below, my thesis, dissertation, or project report in whole or in part in all forms of media, now or hereafter known. I retain all other ownership rights to the copyright of the thesis, dissertation or project report. I also retain the right to use in future works (such as articles or books) all or part of this thesis, dissertation, or project report.en_US
dc.titleEstimating Joint Torques on a Biodex System 3 Dynamometeren_US
dc.contributor.departmentMechanical Engineeringen_US
dc.description.degreeMaster of Scienceen_US of Scienceen_US Polytechnic Institute and State Universityen_US Engineeringen_US
dc.contributor.committeechairMadigan, Michael L.en_US
dc.contributor.committeememberNussbaum, Maury A.en_US
dc.contributor.committeememberGranata, Kevin P.en_US

Files in this item


This item appears in the following Collection(s)

Show simple item record