{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T01:05:14Z","timestamp":1760144714944,"version":"build-2065373602"},"reference-count":40,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2024,5,13]],"date-time":"2024-05-13T00:00:00Z","timestamp":1715558400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Robotics"],"abstract":"<jats:p>This paper is focused on the design and development of the Porcospino Flex, a single-track robot inspired by nature and featuring a meta-material structure. In the earlier version of the Porcospino, the main body was composed of a chain of vertebrae and two end sections linked by flexible joints, but the excessive use of materials in 3D printing and the resulting weight of the robot posed challenges, ultimately leading to a decrease in its overall efficiency and performance. The Porcospino Flex is manufactured through the fused deposition modeling process using acrylonitrile butadiene styrene and thermoplastic polyurethane, featuring a singular meta-material structure vertebral column. The adoption of a lattice structure in the main body of the Porcospino Flex leads to a substantial increase in performance, reducing its weight from 4200 g to 3600 g. Furthermore, the decrease in weight leads to a reduction in material usage and waste, making a substantial contribution to the sustainability of the robot. The discussion focuses on the testing results of the Porcospino Flex prototype, highlighting the enhancements observed compared to its prior version.<\/jats:p>","DOI":"10.3390\/robotics13050076","type":"journal-article","created":{"date-parts":[[2024,5,14]],"date-time":"2024-05-14T10:26:36Z","timestamp":1715682396000},"page":"76","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Porcospino Flex: A Bio-Inspired Single-Track Robot with a 3D-Printed, Flexible, Compliant Vertebral Column"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0003-2781-6774","authenticated-orcid":false,"given":"Shahab","family":"Nodehi","sequence":"first","affiliation":[{"name":"The BioRobotics Institute, Scuola Superiore Sant\u2019Anna, 56127 Pisa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5732-5541","authenticated-orcid":false,"given":"Luca","family":"Bruzzone","sequence":"additional","affiliation":[{"name":"Department of Mechanical, Energy, Management and Transport Engineering (DIME), University of Genoa, 16145 Genoa, Italy"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5680-1550","authenticated-orcid":false,"given":"Mohammadreza","family":"Lalegani Dezaki","sequence":"additional","affiliation":[{"name":"Department of Engineering, Nottingham Trent University, Nottingham NG11 8NS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5302-360X","authenticated-orcid":false,"given":"Ali","family":"Zolfagharian","sequence":"additional","affiliation":[{"name":"School of Engineering, Deakin University, Geelong, VIC 3216, Australia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0707-944X","authenticated-orcid":false,"given":"Mahdi","family":"Bodaghi","sequence":"additional","affiliation":[{"name":"Department of Engineering, Nottingham Trent University, Nottingham NG11 8NS, UK"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,5,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"513","DOI":"10.1007\/978-3-031-04870-8_60","article-title":"SnakeTrack, A Bio-inspired, Single Track Mobile Robot with Compliant Vertebral Column for Surveillance and Inspection","volume":"120","author":"Nodehi","year":"2022","journal-title":"Mech. 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