Center for Human Modeling and Simulation

Document Type

Conference Paper

Date of this Version

June 2002


Postprint version. Published in Proceedings of the Digital Human Modeling Conference, June 2002, pages 217-228.


We are working on modeling a deformable human arm to improve the accuracy of constrained reach analysis. This work is a part of the project "Crew Task Simulation for Maintenance, Training, and Safety". Crewmembers are performing constrained reaches with arm and body for both intra- and extra-vehicular activity (IVA and EVA). They tolerate a certain level of tissue deformation when compressed against a solid object such as an obstacle or the joint in an extravehicular mobility unit (EMU). We have created a deformable arm segment by measuring skin indentation as a function of applied load. In order to populate the model with reasonable tissue properties we have built a simple but effective measuring device to acquire the non-linear force-depth relation from numerous sample points on an arm surface. Given an obstacle, our goal is to determine the reachable space under a certain level of tolerable contact force. We use a finite element method based on living tissue properties and the measured force-depth relations. This work will be applied to estimate the increase in reachable volume of a crewmember an EMU for EVA operation as well as for shirt-sleeved IVA operations.



Date Posted: 11 July 2007

This document has been peer reviewed.