{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,1,17]],"date-time":"2026-01-17T08:30:39Z","timestamp":1768638639491,"version":"3.49.0"},"reference-count":21,"publisher":"MDPI AG","issue":"2","license":[{"start":{"date-parts":[[2024,1,17]],"date-time":"2024-01-17T00:00:00Z","timestamp":1705449600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"National Natural Science Foundation of China","award":["62003345"],"award-info":[{"award-number":["62003345"]}]},{"name":"National Natural Science Foundation of China","award":["62173330"],"award-info":[{"award-number":["62173330"]}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Although the formation control of multi-agent systems has been widely investigated from various aspects, the problem is still not well resolved, especially for the case of distributed output-feedback formation controller design without input information exchange among neighboring agents. Using relative output information, this paper presents a novel distributed reduced-order estimation of the formation error at a predefined time. Based on the proposed distributed observer, a neural-network-based formation controller is then designed for multi-agent systems with connected graphs. The results are verified by both theoretical demonstration and simulation example.<\/jats:p>","DOI":"10.3390\/s24020589","type":"journal-article","created":{"date-parts":[[2024,1,17]],"date-time":"2024-01-17T07:41:28Z","timestamp":1705477288000},"page":"589","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":2,"title":["Distributed NN-Based Formation Control of Multi-Agent Systems: A Reduced-Order Appointed-Time Observer Approach"],"prefix":"10.3390","volume":"24","author":[{"given":"Yuting","family":"Feng","sequence":"first","affiliation":[{"name":"Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Shuai","family":"Sun","sequence":"additional","affiliation":[{"name":"Beijing Institute of Control Engineering, Beijing 100190, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Yuezu","family":"Lv","sequence":"additional","affiliation":[{"name":"Advanced Research Institute of Multidisciplinary Sciences, Beijing Institute of Technology, Beijing 100081, China"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Changhao","family":"Sun","sequence":"additional","affiliation":[{"name":"Qian Xuesen Laboratory of Space Technology, China Academy of Space Technology, Beijing 100094, China"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2024,1,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"424","DOI":"10.1016\/j.automatica.2014.10.022","article-title":"A survey of multi-agent formation control","volume":"53","author":"Oh","year":"2015","journal-title":"Automatica"},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"2283","DOI":"10.1109\/TAC.2014.2303213","article-title":"Cooperative control design for time-varying formations of multi-agent systems","volume":"59","author":"Seuret","year":"2014","journal-title":"IEEE Trans. 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