Abstract
Large animal models, while valuable, are expensive, time-consuming, and limited to discrete interventional or terminal timepoints, while existing benchtop models do not offer an accurate representation of the esophageal environment. Moreover, current pre-clinical models cannot effectively simulate swallowing dysfunction (dysphagia), restricting progress in understanding motility disorders like achalasia and hindering evidence-based dietary recommendations. In response, we present RoboGullet, a biomimetic soft-robotic model with independent localized longitudinal and circumferential muscle actuation, enabling, for the first time, simulation of both normal and diseased esophageal motility. We further enhance realism with a biohybrid variant, RoboGullet + , incorporating porcine esophageal mucosa/submucosa. We demonstrate this platform’s versatility through three key applications: assessing stent migration, simulating achalasia I-III within clinical diagnostic criteria, and analyzing bolus swallowing. Our findings reveal that: (1) stent migration increases over fivefold when incorporating longitudinal muscle movement versus isolated circumferential; (2) using a viscous non-Newtonian bolus improves high-resolution manometry diagnostic sensitivity of Achalasia III through increasing the Distal Latency diagnostic metric by 20.83%; and (3) stirring Greek-style yoghurt (common non-Newtonian dietary recommendation) significantly improves bolus transit versus unstirred for Achalasia Types I-II patients. This establishes RoboGullet+ as a powerful translational tool, advancing our understanding of esophageal motility and its therapeutic interventions.
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The authors declare that the data supporting the findings of this study are available within the paper and its supplementary information files. Any additional requests for information can be directed to the corresponding author. Source data is provided with this paper. Source data are provided with this paper.
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Acknowledgements
The authors thank Dr. Gang Shen for support with frictional testing. N.A.P. gratefully acknowledges the Visiting Professor position in the MIT Department of Mechanical Engineering during his academic leave from Northwestern University in Fall 2023 and Winter 2024. S.K. acknowledges Mark Fitzmaurice and Sword Medical Ltd. for the loan of equipment. Funding Taighde Éireann— Research Ireland grant GOIPG/2023/3917 (SK) Taighde Éireann—Research Ireland grant 13/RC/2073_P2 (E.D.O’C.) Karl van Tassel (1925) Career Development Professorship (GT) Department of Mechanical Engineering, MIT (GT) Division of Gastroenterology, Brigham and Women’s Hospital (GT).
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Conceptualization: S.K., W.W.C., G.T., and E.D.O.’C. Methodology: S.K., G.T., N.A.P., and E.D.O.’C. Investigation: S.K. Funding acquisition: S.K., G.T., and E.D.O.’C. Project administration: G.T. and E.D.O.’C. Supervision: G.T. and E.D.O.’C. Writing—original draft: S.K. Writing—review & editing: S.K., N.A.P., W.W.C., G.T., and E.D.O.’C.
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Kilroy, S., Patankar, N.A., Chan, W.W. et al. A Soft-Robotic Biomimetic Benchtop Model for Esophageal Motility Simulation. Nat Commun (2026). https://doi.org/10.1038/s41467-026-70260-2
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DOI: https://doi.org/10.1038/s41467-026-70260-2
