Monolithic Soft Fibrous Valves Capable of Generating Air Pressure Cutoff, Maintaining, and Oscillation for Pneumatic Systems

Abstract Soft pneumatic robotics are designed for safe and compliant interaction with the environment or humans. However, the pneumatic systems used for actuation and protection are still relatively bulky and rely on rigid components such as solenoid valves and pressure regulators. This study presents the design and analysis of soft fibrous valves (SFVs) with internal tiny channels and external helical structures, which could be used in soft pneumatic systems. Made from soft material, SFVs demonstrate unique capabilities in controlling pressure by partial expansion under specific pressure. Three types of SFVs are designed: 1) SFV‐C is designed to protect soft pneumatic actuators by cutting off airflow under excessive pressure; 2) SFV‐M maintains pressure in actuators when the input pressure abruptly drops, preventing potential damage to the operated object; 3) SFV‐O produces oscillating pressure output without electronic control supplied by constant pressure source. Theoretical modeling and experimental validations are conducted to investigate the performance of the SFVs under various stretching, twisting, and pressure conditions. Furthermore, fully flexible SFVs are designed to enhance their compliance and resistance to external impacts. Overall, the SFVs offer promising solutions for pressure control and protection in soft pneumatic systems, enabling safer and more effective operations in various scenarios.