Historically, spacesuit mobility has been characterized by directly measuring both range of motion and joint torque of individual anatomic joints. The work detailed herein aims to improve on this method, which is often prone to uncertainly, lack of repeatability, and a general lack of applicability to real-world functional tasks. Specifically, the goal of this work is to characterize suited mobility performance by directly measuring the metabolic performance of the occupant. Pilot testing was conducted in 2013, employing three subjects performing a range of functional tasks in two different suits prototypes, the Mark III and Z-1. Cursory analysis of the results shows the approach has merit, with consistent performance trends toward one suit over the other. Forward work includes the need to look at more subjects, a refined task set, and another suit in a different mass/mobility regime to validate the approach

McFarland, Shane M.

Norcross, Jason R.

Tucson, ArizonaThe 44th International Conference on Environmental Systems was held in Tuscon, Arizona, USA on 13 July 2014 through 17 July 2014.Shane M McFarland, Wyle/NASA-Johnson Space Center, USAJason R. Norcross, Wyle/NASA-Johnson Space Center, USAHistorically, spacesuit mobility has been characterized by directly measuring both range of motion and joint torque of individual anatomic joints. The work detailed herein aims to improve on this method, which is often prone to uncertainly, lack of repeatability, and a general lack of applicability to real-world functional tasks. Specifically, the goal of this work is to characterize suited mobility performance by directly measuring the metabolic performance of the occupant. Pilot testing was conducted in 2013, employing three subjects performing a range of functional tasks in two different suits prototypes, the Mark III and Z-1. Cursory analysis of the results shows the approach has merit, with consistent performance trends toward one suit over the other. Forward work includes the need to look at more subjects, a refined task set, and another suit in a different mass/mobility regime to validate the approach

TTU DSpace Repository (Texas Tech University)

A Novel Method for Characterizing Spacesuit Mobility Through Metabolic Cost

NASA Technical Reports Server

Spacesuit mobility has historically been defined and characterized by a combination of range of motion and joint torque of the individual anatomical joints when performing isolated motions meant to drive that joint only in a given orthogonal plane. While this has been the standard approach for several decades, there are numerous shortcomings that suit designers and engineers would like to see rectified. First, the lack of a standardized method for collecting both range of motion and joint torque translates to many different test setups, procedures and methods of data analysis. Second, all of these previously used methods for data collection lack some degree of repeatability, even within the same test setup and the same conductor; in addition, attempts at higher fidelity data collection techniques require high overhead and cost with minimal improvement. Lastly, isolated motions in standard anatomical planes are not representative of realworld tasks that a crewmember would be performing during an EVA, be it microgravity or surface exploration based. To address these shortcomings, options are being explored within the Space Suit and Crew Survival Systems Branch to ascertain the feasibility of an alternative approach to defining mobility - one that is more repeatable, lower overhead, and more tied to functional EVA tasks. This paper serves to document the first attempt at such an alternative option - one that looks at the metabolic energycost of a spacesuit. In other words, can we objectively compare the mobility of a spacesuit by evaluating the metabolic cost of that suit to the wearer while performing a battery of functional EVA tasks

Norcross, Jason

McFarland, Shane

A novel method for characterizing spacesuit mobility through metabolic cost   
Author: Shane McFarland, Jason Norcross 
Spacesuit mobility has historically been defined and characterized by a combination of range of motion 
and joint torque of the individual anatomical joints when performing isolated motions meant to drive 
that joint only in a given orthogonal plane. While this has been the standard approach for several 
decades, there are numerous shortcomings that suit designers and engineers would like to see rectified. 
First, the lack of a standardized method for collecting both range of motion and joint torque translates 
to many different test setups, procedures and methods of data analysis. Second, all of these previously‐
used methods for data collection lack some degree of repeatability, even within the same test setup and 
the same conductor; in addition, attempts at higher fidelity data collection techniques require high 
overhead and cost with minimal improvement. Lastly, isolated motions in standard anatomical planes 
are not representative of real‐world tasks that a crewmember would be performing during an EVA, be it 
microgravity or surface exploration based.  
To address these shortcomings, options are being explored within the Space Suit and Crew Survival 
Systems Branch to ascertain the feasibility of an alternative approach to defining mobility – one that is 
more repeatable, lower overhead, and more tied to functional EVA tasks. This paper serves to document 
the first attempt at such an alternative option – one that looks at the metabolic energy‐cost of a 
spacesuit. In other words, can we objectively compare the mobility of a spacesuit by evaluating the 
metabolic cost of that suit to the wearer while performing a battery of functional EVA tasks? 
https://ntrs.nasa.gov/search.jsp?R=20140004043 2019-08-29T14:22:53+00:00Z


A Novel Method for Characterizing Spacesuit Mobility Through Metabolic Cost

Abstract

Similar works

Full text

Available Versions

TTU DSpace Repository (Texas Tech University)

NASA Technical Reports Server

NASA Technical Reports Server