Industrial passive exoskeletons are used to assist workers in performing repetitive and physically demanding tasks, in fields such as manufacturing. These devices aim to reduce biomechanical stress on specific joint or anatomical regions, with the ultimate goal of reducing the risk of work-related musculoskeletal disorders. Among the various joints subjected to overwork, the shoulder joint presents a unique challenge due to its high degrees of freedom (DOF) and wide range of motion (ROM), which make it difficult to design support mechanisms that do not interfere with physiological movements. This thesis focuses on the biomechanical analysis and functional enhancement of a passive upper-limb exoskeleton prototype which employs two Pneumatic Artificial Muscles (PAMs).