{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,11,28]],"date-time":"2025-11-28T12:23:54Z","timestamp":1764332634740,"version":"build-2065373602"},"reference-count":23,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2018,6,30]],"date-time":"2018-06-30T00:00:00Z","timestamp":1530316800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Algorithms"],"abstract":"<jats:p>Classical fractional order controller tuning techniques usually consider the frequency domain specifications (phase margin, gain crossover frequency, iso-damping) and are based on knowledge of a process model, as well as solving a system of nonlinear equations to determine the controller parameters. In this paper, a novel auto-tuning method is used to tune a fractional order PI controller. The advantages of the proposed auto-tuning method are two-fold: There is no need for a process model, neither to solve the system of nonlinear equations. The tuning is based on defining a forbidden region in the Nyquist plane using the phase margin requirement and determining the parameters of the fractional order controller such that the loop frequency response remains out of the forbidden region. Additionally, the final controller parameters are those that minimize the difference between the slope of the loop frequency response and the slope of the forbidden region border, to ensure the iso-damping property. To validate the proposed method, a case study has been used consisting of a pick and place movement of an UR10 robot. The experimental results, considering two different robot configurations, demonstrate that the designed fractional order PI controller is indeed robust.<\/jats:p>","DOI":"10.3390\/a11070095","type":"journal-article","created":{"date-parts":[[2018,7,2]],"date-time":"2018-07-02T10:56:52Z","timestamp":1530529012000},"page":"95","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":12,"title":["Experimental Validation of a Novel Auto-Tuning Method for a Fractional Order PI Controller on an UR10 Robot"],"prefix":"10.3390","volume":"11","author":[{"given":"Cristina I.","family":"Muresan","sequence":"first","affiliation":[{"name":"Department of Automation, Technical University of Cluj-Napoca, Memorandumului Street, No. 28, Cluj Napoca 400020, Romania"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5880-6275","authenticated-orcid":false,"given":"Cosmin","family":"Copot","sequence":"additional","affiliation":[{"name":"Department of Electromechanics, University of Antwerp, Op3Mech, Groenenborgerlaan 171, 2020 Antwerp, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Isabela","family":"Birs","sequence":"additional","affiliation":[{"name":"Department of Automation, Technical University of Cluj-Napoca, Memorandumului Street, No. 28, Cluj Napoca 400020, Romania"},{"name":"Department of Electrical Energy, Metals, Mechanical Constructions and Systems, Ghent University, Research Group on Dynamical Systems and Control (DySC), EEDT Group, Member of Flanders Make, Technologiepark 914, 9052 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Robin","family":"De Keyser","sequence":"additional","affiliation":[{"name":"Department of Electrical Energy, Metals, Mechanical Constructions and Systems, Ghent University, Research Group on Dynamical Systems and Control (DySC), EEDT Group, Member of Flanders Make, Technologiepark 914, 9052 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Steve","family":"Vanlanduit","sequence":"additional","affiliation":[{"name":"Department of Electromechanics, University of Antwerp, Op3Mech, Groenenborgerlaan 171, 2020 Antwerp, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7685-035X","authenticated-orcid":false,"given":"Clara M.","family":"Ionescu","sequence":"additional","affiliation":[{"name":"Department of Automation, Technical University of Cluj-Napoca, Memorandumului Street, No. 28, Cluj Napoca 400020, Romania"},{"name":"Department of Electrical Energy, Metals, Mechanical Constructions and Systems, Ghent University, Research Group on Dynamical Systems and Control (DySC), EEDT Group, Member of Flanders Make, Technologiepark 914, 9052 Ghent, Belgium"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2018,6,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Vilanova, R., and Visioli, A. 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