{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,21]],"date-time":"2026-01-21T17:23:54Z","timestamp":1769016234538,"version":"3.49.0"},"reference-count":23,"publisher":"MDPI AG","issue":"13","license":[{"start":{"date-parts":[[2021,6,30]],"date-time":"2021-06-30T00:00:00Z","timestamp":1625011200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Applied Sciences"],"abstract":"<jats:p>This paper presents a legged-wheeled hybrid robotic vehicle that uses a combination of rigid and non-rigid joints, allowing it to be more impact-tolerant. The robot has four legs, each one with three degrees of freedom. Each leg has two non-rigid rotational joints with completely passive components for damping and accumulation of kinetic energy, one rigid rotational joint, and a driving wheel. Each leg uses three independent DC motors\u2014one for each joint, as well as a fourth one for driving the wheel. The four legs have the same position configuration, except for the upper hip joint. The vehicle was designed to be modular, low-cost, and its parts to be interchangeable. Beyond this, the vehicle has multiple operation modes, including a low-power mode. Across this article, the design, modeling, and control stages are presented, as well as the communication strategy. A prototype platform was built to serve as a test bed, which is described throughout the article. The mechanical design and applied hardware for each leg have been improved, and these changes are described. The mechanical and hardware structure of the complete robot is also presented, as well as the software and communication approaches. Moreover, a realistic simulation is introduced, along with the obtained results.<\/jats:p>","DOI":"10.3390\/app11136116","type":"journal-article","created":{"date-parts":[[2021,7,1]],"date-time":"2021-07-01T02:44:39Z","timestamp":1625107479000},"page":"6116","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Design, Modeling, and Control of an Autonomous Legged-Wheeled Hybrid Robotic Vehicle with Non-Rigid Joints"],"prefix":"10.3390","volume":"11","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7840-0333","authenticated-orcid":false,"given":"V\u00edtor H.","family":"Pinto","sequence":"first","affiliation":[{"name":"FEUP\u2014Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Campus of FEUP, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2631-9493","authenticated-orcid":false,"given":"In\u00eas N.","family":"Soares","sequence":"additional","affiliation":[{"name":"FEUP\u2014Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-3411-4802","authenticated-orcid":false,"given":"Marco","family":"Rocha","sequence":"additional","affiliation":[{"name":"FEUP\u2014Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7902-1207","authenticated-orcid":false,"given":"Jos\u00e9","family":"Lima","sequence":"additional","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Campus of FEUP, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"CeDRI\u2014Research Centre in Digitalization and Intelligent Robotics, School of Technology and Management, Polytechnic Institute of Bragan\u00e7a, Santa Apol\u00f3nia Campus, 5300-253 Bragan\u00e7a, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5499-1730","authenticated-orcid":false,"given":"Jos\u00e9","family":"Gon\u00e7alves","sequence":"additional","affiliation":[{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Campus of FEUP, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"CeDRI\u2014Research Centre in Digitalization and Intelligent Robotics, School of Technology and Management, Polytechnic Institute of Bragan\u00e7a, Santa Apol\u00f3nia Campus, 5300-253 Bragan\u00e7a, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4846-271X","authenticated-orcid":false,"given":"Paulo","family":"Costa","sequence":"additional","affiliation":[{"name":"FEUP\u2014Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"},{"name":"CRIIS\u2014Centre for Robotics in Industry and Intelligent Systems, INESC TEC\u2014Institute for Systems and Computer Engineering, Technology and Science, Campus of FEUP, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"10822","DOI":"10.3182\/20080706-5-KR-1001.01833","article-title":"BigDog, the Rough-Terrain Quadruped Robot","volume":"41","author":"Raibert","year":"2008","journal-title":"IFAC Proc. 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