Effects of EVA Glove on Hand Performance

The human hand is a very particular limb: it has a wide range of degrees of freedom, permitting to achieve a great variety of movements, and is also one of the most sensorized parts of the human body. These characteristics make it the most important tool for astronauts to perform extravehicular activity (EVA). However, mandatory EVA equipment strongly reduces hand performances, in particular as regards dexterity, tactile perception, mobility and fatigue. Several studies have been conducted to determine the influence of the EVA glove on manual capabilities, both in the past and more recently. This study presents experimental data regarding the performance decay which occurs in forces, fatigue and capability to execute tasks when wearing a non pressurized EVA glove, in comparison with bare-handed potential. Moreover, mechanical resistance of the glove has been measured and imposed pressure maps are presented. Results yield a deeper knowledge on how EVA gloves hinder human hand performance and how this is related to their stiffness.