{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,18]],"date-time":"2026-01-18T03:01:41Z","timestamp":1768705301066,"version":"3.49.0"},"reference-count":34,"publisher":"MDPI AG","issue":"21","license":[{"start":{"date-parts":[[2019,10,30]],"date-time":"2019-10-30T00:00:00Z","timestamp":1572393600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, fault detection and fault-tolerant control strategies are proposed to handle the issues of both actuator faults and disturbances in a hexacopter. A dynamic model of a hexacopter is first derived to develop a model-based fault detection system. Secondly, the altitude control based on a sliding mode and disturbance observer is presented to tackle the disturbance issue. Then, a nonlinear Thau observer is applied to estimate the states of a hexacopter and to generate the residuals. Using a fault detection unit, the motor failure is isolated to address the one or two actuator faults. Finally, experimental results are tested on a DJI F550 hexacopter platform and Pixhawk2 flight controller to verify the effectiveness of the proposed approach. Unlike previous studies, this work can integrate fault detection and fault-tolerant control design as a single unit. Moreover, the developed fault detection and fault-tolerant control method can handle up to two actuator failures in presence of disturbances.<\/jats:p>","DOI":"10.3390\/s19214721","type":"journal-article","created":{"date-parts":[[2019,10,31]],"date-time":"2019-10-31T05:18:26Z","timestamp":1572499106000},"page":"4721","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":48,"title":["Actuator Fault Detection and Fault-Tolerant Control for Hexacopter"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-5100-6264","authenticated-orcid":false,"given":"Ngoc Phi","family":"Nguyen","sequence":"first","affiliation":[{"name":"Department of Aerospace Engineering, Sejong University, Seoul 143-747, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5632-9399","authenticated-orcid":false,"given":"Nguyen","family":"Xuan Mung","sequence":"additional","affiliation":[{"name":"Department of Aerospace Engineering, Sejong University, Seoul 143-747, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sung Kyung","family":"Hong","sequence":"additional","affiliation":[{"name":"Department of Aerospace Engineering, Sejong University, Seoul 143-747, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,10,30]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"1335","DOI":"10.1016\/j.jfranklin.2013.10.021","article-title":"Quadcopter formation flight control combining MPC and robust feedback linearization","volume":"351","author":"Zhao","year":"2014","journal-title":"J. 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