S-DOT: Soft Dot-Structured Surface Pattern for Enhanced Grip and Comfort in Exoskeleton Straps

In exoskeleton leg strap applications, maintaining a reliable and enhanced grip, particularly under varying conditions, remains an ongoing challenge. Conventional ethylenevinyl acetate (EVA) foam solutions, while offering some degree of comfort, often fail to provide consistent grip stability, especially when exposed to moisture or oil. To address this limitation, this study investigates an alternative solution using a combination of soft materials, such as silicone and surface pattern design. These patterns are meticulously crafted to optimize load distribution and minimize high-pressure points without compromising grip efficiency. Through comprehensive experiments and analysis under dry, moist, and oily conditions, we compare the performance of the proposed silicone-patterned straps against traditional EVA foam straps. The results reveal that the soft dot-structured surface pattern (S-DOT)—silicone with a dot pattern—significantly outperforms EVA foam, exhibiting the lowest slip distance (<10 mm) and showcasing its potential as a simple but effective anti-slip solution for enhanced exoskeleton wearability. The findings of this study suggest a promising future for patterned silicone-based techniques in improving force dispersion and enhancing exoskeleton wearability in real-world scenarios.