Shear‐Isolating Actuation System for Exosuit Using Movable Pulley With Webbing‐Driven Mechanism

Tendon‐driven soft exosuits offer a lightweight solution for physical assistance but pose a critical safety concern: skin chafing induced by relative motion between the tendon and the wearer.Existing mitigation strategies, such as intermediate protective layers, often fail to fully isolate shear forces or to avoid introducing additional bulk that compromises usability. We propose a shear‐isolating actuation system that substantially reduces skin chafing through kinematic decoupling. By integrating a movable pulley with flat‐profile webbing, the proposed mechanism reconfigures the tendon path into a stationary shield layer and a moving driving layer, thereby relocating most of the relative motion at the skin interface into internal sliding between the tendon layers. The developed actuator achieves a compact form factor (109 cm 3 , 145 g) while generating a high assistive force of 150 N. Comprehensive evaluations, including benchtop abrasion tests using bio‐mimetic skin surrogates and dynamic walking experiments, demonstrate the system's improved interface safety. These results indicate that the proposed mechanism shows strong potential to improve skin safety and reduce chafing without additional protective garments.