🤖 AI Summary
This study addresses the ongoing challenge of fabricating complex soft pneumatic actuators that simultaneously achieve geometric fidelity, compliance, structural integrity, and airtightness. The authors systematically evaluate the suitability of various fabrication methods—including heat-shrink forming, silicone casting, powder- and photopolymer-based additive manufacturing, and fused deposition modeling (FDM)—through iterative stages of process screening, baseline fabrication, failure analysis, and optimization to distinguish inherent limitations from correctable defects. A design-for-manufacturing approach is proposed, revealing that airtightness depends not only on wall thickness but critically on extrusion path architecture, and underscoring the importance of support-free geometries in scenarios where internal post-processing is constrained. Results demonstrate that FDM offers the greatest adaptability, with its primary shortcomings effectively mitigated through targeted process refinements, thereby providing practical guidance for developing high-performance soft pneumatic actuators.
📝 Abstract
Manufacturing complex soft pneumatic actuators remains challenging because geometric fidelity, compliance, structural integrity, and airtightness must be achieved simultaneously. This study presents a manufacturing-focused evaluation of several fabrication routes for complex pneumatic structures, including heat-shrink forming, silicone casting, powder- and liquid-based additive manufacturing, and fused deposition modeling (FDM). The processes were assessed through process screening, baseline fabrication, failure analysis, and process improvement to distinguish inherent process limitations from correctable manufacturing defects. Heat-shrink forming was limited by geometric conformity, casting by mold accessibility and bonded interfaces, powder-based methods by residual material trapped within enclosed passages, and digital light processing by the material properties and post-processing requirements of the investigated system. FDM provided the most adaptable route because its dominant defects could be progressively reduced through process optimization. The results further showed that airtightness depends not only on nominal wall thickness but also on extrusion-path architecture, while support-free geometry is important when access for internal post-processing is limited. These findings establish a practical design-for-manufacturing approach in which process selection is guided by the compatibility between actuator architecture and manufacturing constraints. The proposed approach provides practical guidance for developing complex, flexible, and airtight soft pneumatic actuators for soft robotic applications