Pressure characterization between the upper body and space suit during mission-realistic movements

Gas-pressurized space suits are incredibly well engineered tools allowing astronauts to perform critical duties. However, current gas pressurized space suits have an inherent stiffness, causing fatigue, unnecessary energy expenditure, and in some instances injury. Prior to this research effort there was no technology allowing the human-space suit interface to be measured internally. We quantify and evaluate human-space suit interaction with a novel pressure sensing tool, focusing on the arm under different loading regimes. An experiment was performed inside the Mark III space suit at NASA Johnson Space Center. One highly experienced male subject was asked to perform a series of mission-realistic movements for planetary exploration: kneel and recover, boot tighten, and prone and recover. These motions were performed in conjunction with an upper-body motion experiment to assess human-space suit interaction during controlled movements. The subject was asked to perform these mission-realistic tasks to determine the utility of the pressure sensing system in experiments not intentionally directed at loading the sensors. Loading over the upper forearm for each task was compared against experimental video to determine motion induced loading on the subject's body and gave insight into how the system could be used to index the person's body inside the suit and determine how motion occurs and the nature of that motion. We propose future improvements for the characterization of human biomechanics and injury mechanisms inside the space suit.