Full Content is available to subscribers

Subscribe/Learn More  >

Comparison of Cylindrical Wrapping Geometries to Via Points for Modeling Muscle Paths in the Estimation of Sit-to-Stand Muscle Forces

[+] Author Affiliations
Valerie Norman-Gerum, John McPhee

University of Waterloo, Waterloo, ON, Canada

Paper No. DETC2013-13437, pp. V07AT10A011; 8 pages
  • ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference
  • Volume 7A: 9th International Conference on Multibody Systems, Nonlinear Dynamics, and Control
  • Portland, Oregon, USA, August 4–7, 2013
  • Conference Sponsors: Design Engineering Division, Computers and Information in Engineering Division
  • ISBN: 978-0-7918-5596-6
  • Copyright © 2013 by ASME


To better understand the complexities of rising from a seated to a standing position, a model of the human has been created. Sit-to-stand kinematics as well as ground reaction forces were measured experimentally and are used in an inverse dynamics analysis to estimate nine muscle forces during motion.

Calculated muscle forces are sensitive to assumptions made when modeling muscle paths. Changes in the line of action of a muscle due to interaction with anatomical constraints are often accounted for by including fixed via points in a model. Here an alternate approach of representing anatomical constraints using three-dimensional cylindrical geometries is derived and presented. In this mathematical model the course of the muscle is determined as the minimum-length path where the muscle is allowed to wrap freely over the surface of the cylinder.

Muscle forces are estimated for sit-to-stand by resolving net joint torques using an objective function giving preference to solutions minimizing both muscle stresses and abrupt changes in muscle forces. This is the first time muscle forces have been presented for sit-to-stand using a musculoskeletal model with included anatomical constraints represented using cylindrical wrapping geometries alone. A comparison of calculated muscle force patterns using fixed via points and wrapping points versus three-dimensional wrapping surfaces is made with reference to electromyographic phase data. For the sit-to-stand motion, the inclusion of anatomical constraints as three-dimensional cylindrical geometries results in calculation of muscle forces more true to the experimental data and more consistent with the belief that gradual motions are created by gradual changes in muscle force over time.

Copyright © 2013 by ASME
Topics: Modeling , Muscle



Interactive Graphics


Country-Specific Mortality and Growth Failure in Infancy and Yound Children and Association With Material Stature

Use interactive graphics and maps to view and sort country-specific infant and early dhildhood mortality and growth failure data and their association with maternal

Citing articles are presented as examples only. In non-demo SCM6 implementation, integration with CrossRef’s "Cited By" API will populate this tab (http://www.crossref.org/citedby.html).

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In