Previous artificial lung surrogates used hydrogels or balloon-like inflatable structures without reproducing the alveolar network or breathing action within the lung. A physiologically accurate, air-filled lung model inspired by soft robotics is presented. The model, soft robotic surrogate lung (SRSL), is composed of clusters of artificial alveoli made of platinum-cured silicone, with internal pathways for air flow. Mechanical tests in conjunction with full-field image and volume correlation techniques characterize the SRSL behavior. SRSLs enable both healthy and pathological lungs to be studied in idealized cases. Although simple in construction, the connected airways demonstrate clearly the importance of an inflatable network for capturing basic lung behavior (compared to more simplified lung surrogates). The SRSL highlights the potentially damaging nature of local defects caused by occlusion or overdistension (present in conditions such as chronic obstructive pulmonary disease). The SRSL is developed as a potential upgrade to conventional surrogates used for injury risk predictions in trauma. The deformation of the SRSL is evaluated against blast trauma using a shock tube. The SRSL was compared to other conventional trauma surrogate materials and showed greatest similarity to lung tissue. The SRSL has the potential to complement conventional biomechanical studies and reduce animal use in basic biomechanics studies, where high severity protocols are used.
Keywords: biomechanics; image correlation; lung; soft robotics; trauma.