Utilizing Finite Element Analysis (FEA) to Predict Fit and Performance of an EVA Lower Arm Assembly Pressure Garment

Digital human modeling (DHM) is a developing field of study that has proven useful in human systems engineering to analyze how the design of space systems are influenced by human factors and anthropometrics. The overarching benefit of this analysis is the ability to predict human performance of a design prior to fabrication, which also reduces prototype building and testing costs. Specific to space suit systems, DHM is currently being used to interface 3D scans of human subjects with CAD models of the new Exploration Extravehicular Mobility Unit (xEMU) to determine preliminary sizing of hard components that will accommodate the full anthropometric range of crewmembers. While extensive work has been done to model the influence of hard pressure garment components (i.e. hard upper torso and waist-brief-hip assemblies), little research exists that analyzes the influence of the multi-layered fabric components of pressure garments on human fit and performance after pressurization. Since finite element analysis (FEA) tools have been utilized extensively to model inflatable fabric pressure vessels for space habitats and other applications, similar FEA tools were applied to a pressurized EVA suit arm (using the EMU as a model). The results of this paper evaluate the effects of the location, number, and size of convolutes on the location of the presumed suit elbow buckle, force and torque required for bending at the elbow, and contact pressures experienced on the arm. The goal of this FEA research is to provide a first step in the modeling framework required to predict and analyze fit and performance for the multilayered �soft� pressure garments. Additionally, the creation of these models will help to better understand which design factors of soft space suit components have the greatest influence on pressure garment fit and predicted performance.