Case Study on the Additive Manufacturability of Printed Soft-Robotic Bending Actuators

In order to flexibly handle products with varying shapes and materials, soft robotic pneumatic network actuators (pneunets) have been proposed due to their compliant behavior. Pneunets are manufactured with manual casting or with additive manufacturing (AM). In this work, the four AM technologies fused filament fabrication (FFF), stereolithography (SLA), selective laser sintering (SLS) and polyjetting (PJ) are compared for manufacturing pneunets. Results are analyzed regarding manufacturability, deflection behavior and airtightness. SLS and FFF show best results and least manufacturing restrictions for thermoplastic polyurethane pneunets. SLA and PJ lead to manufacturing specific deficits and critical material failures during pneunet operation.