Evaluating gloved hand performance based on the mechanical properties of the applied material.

The hands are the most complex organs of the body for performing various activities. Therefore, it is critical to protect them against dangers. Protective gloves can reduce or prevent injuries, but they can downgrade hand performance in various aspects, including tactile sensitivity, strength, grip force and hand dexterity. In this study, eight protective gloves with different designs and materials were made. The study investigated the influence of the number of layers and several characteristics, e.g., mass per square meter, thickness, bending stiffness and compressibility, on the gloved hand performance regarding protection ability, tactile sensitivity, strength capability and manual dexterity. The results indicated that despite the improving effects of increasing layer thickness, weight, bending energy and compressibility on protection ability, the gloves diminish tactile sensitivity, grip and pinch force, and manual dexterity. Therefore, it is necessary to select an optimum design to ensure a satisfactory trade-off between protection and performance.

Characterization of the effect of fabric's tensile behavior and sharp object properties on the resistance against penetration.

In this study, the penetration procedure of sharp objects with various geometries in the fabric was considered. To this end, five objects consisted of two single edged knives, a double edged knife and two spikes were employed. Tests were performed on fabrics with different applications such as shirting, worsted, elastic denim, artificial leather and tarpaulin. The fabric's tensile behavior and the tools geometry were probed. Then, the stab resistances of fabrics against mentioned devices were examined and their penetration force, depth and energy were considered. Outcomes illustrated that tool's geometry has a determinant influence on the stabbing parameters. Fabrics with lower tensile modulus extend easily; therefore, higher penetration depth was obtained and this fact postponed the penetration phenomenon. In addition, the increase in the fabric's strength resulted in higher penetration force. A direct relation was achieved between sharp tool's geometry and fabrics destruction, in a way that damages obtained by knives are straight and slim line with cut yarns and fibers in the cross-section; however, the penetration of spikes makes damage with a circle shape and torn and protruded fibers are observed in the cross-section.