Origami-inspired muscle augmentation

Abstract

This thesis explores the application of origami-inspired inflatable structured sheets to enhance muscle function for individuals with muscle impairments, specifically focusing on the biceps brachii muscle. These sheets induce muscle contraction through pneumatic pressure, aimed at facilitating forearm flexion by strategically incorporating patterns that create air pockets. These sheets hold significant potential for assisting individuals with conditions such as muscular dystrophy, cerebral palsy, or spinal cord injuries. Compared to traditional solutions, they offer less bulkiness and greater adaptability, promoting natural movement and improving limb mobility. Furthermore, these sheets can be customized to fit various muscle contours and integrated with mechatronics for real-time adjustments, enhancing stability and resilience in muscle support applications. The study begins with the development of a comprehensive test setup that simulates muscle extension and flexion, integrating mechanical and electrical components. This setup includes a silicone muscle model of the biceps brachii muscle, essential for evaluating sheet performance. Subsequent chapters delve into the evaluation of materials and patterns for the sheets. Materials such as PVC-film, TPU-film, PET-film, and Nylon are assessed for biocompatibility, flexibility, temperature sensitivity, and adhesion characteristics. Here, TPU-film emerges as the most promising material due to its durability and adhesive properties under pressure. For the evaluation of the patterns, a preliminary study is conducted to determine optimal patterns that effectively respond to pneumatic pressure for inducing muscle contraction. This study reveals that combinations of parallel lines and zigzag structures show the most promising results among the tested patterns. Building on these findings, various structured sheets are tested around the muscle model to assess their ability to activate and contract muscles. An optimal structure is selected that conforms closely to the contours of the muscle model, ensuring optimal airflow and maximizing the potential for effective muscle contraction. However, challenges such as leakage affecting pressure retention and muscle activation are identified, underscoring the need for further optimization to achieve practical muscle activation and flexion. In conclusion, while this research provides valuable insights into the feasibility of origami-inspired structured sheets for muscle augmentation, ongoing refinement is crucial to address practical challenges and optimize performance.