The second skin approach : skin strain field analysis and mechanical counter pressure prototyping for advanced spacesuit design

The primary aim of this thesis is to advance the theory of advanced locomotion mechanical counter pressure (MCP) spacesuits by studying the changes in the human body shape during joint motion. Two experiments take advantage of three-dimensional laser scan technology to measure the shape changes of the human body. The first experiment is an analysis of the surface area and volume of the thigh, knee, calf, and entire leg during knee flexion. The second experiment is an analysis of the full-field strain on the skin surface of the leg during knee flexion. A repeatable and quantitative technique for mapping the leg skin strain field is developed. The results of the algorithm indicate the magnitude of strain over the entire surface of the leg, as well as the direction of minimum leg skin stretching during knee flexion. For 88% of the leg surface, knee flexion causes skin strain between -0.3 and 0.3 (less than 30% contraction or extension). However, just below the patella, longitudinal strain is as high as 0.7, and at the knee hollow, it is as low as -0.6. Circumferential strain values are as high as 1.0 and 0.5 just below the patella and over the calf muscle, respectively, and along the anterior surface of the lower leg, they are as low as -0.7. The leg area, volume, and skin strain results lead to quantitative design requirements for highly mobile second skin spacesuits, and they inspire two prototype MCP leg sleeves: a hybrid urethane-foam bladder garment and a skintight nylon fiber lines of non-extension garment. These two prototypes are constructed and tested for mobility and skin surface pressure. Pressurization of the hybrid foam prototype inhibits leg mobility.

Department dc:contributor.department

Massachusetts Institute of Technology. Dept. of Aeronautics and Astronautics.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2005

Author dc:creator

• Bethke, Kristen (Kristen Ann)

Advisor dc:contributor.advisor

• Dava J. Newman.

• Aeronautics and Astronautics.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/32443

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/32443