{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,6]],"date-time":"2026-02-06T03:02:00Z","timestamp":1770346920735,"version":"3.49.0"},"reference-count":39,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2025,4,14]],"date-time":"2025-04-14T00:00:00Z","timestamp":1744588800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Funda\u00e7\u00e3o para a Ci\u00eancia e a Tecnologia (FCT)"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The increasing use of Unmanned Aerial Vehicles (UAVs) demands enhanced flight safety systems. This study presents the development of an affordable and efficient Sense and Avoid (S&amp;A) system for small fixed-wing UAVs, typically under 25 kg and fly at speeds of up to 15 m\/s. The system integrates multiple non-cooperative sensors, two ultrasonic sensors, two laser rangefinders, and one LiDAR, along with a Pixhawk 6X flight controller and a Raspberry Pi CM4 companion computer. A collision avoidance algorithm utilizing the Vector Field Histogram method was implemented to process sensor data and generate real-time trajectory corrections. The system was validated through experiments using a ground rover, demonstrating successful obstacle detection and avoidance with real-time trajectory updates at 10 Hz.<\/jats:p>","DOI":"10.3390\/s25082460","type":"journal-article","created":{"date-parts":[[2025,4,14]],"date-time":"2025-04-14T06:18:36Z","timestamp":1744611516000},"page":"2460","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":3,"title":["On the Development of a Sense and Avoid System for Small Fixed-Wing UAV"],"prefix":"10.3390","volume":"25","author":[{"given":"Bruno M. B.","family":"Pedro","sequence":"first","affiliation":[{"name":"IDMEC, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9399-7967","authenticated-orcid":false,"given":"Andr\u00e9 C.","family":"Marta","sequence":"additional","affiliation":[{"name":"IDMEC, Instituto Superior T\u00e9cnico, Universidade de Lisboa, 1049-001 Lisboa, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2025,4,14]]},"reference":[{"key":"ref_1","unstructured":"Fahlstrom, P.G., Gleason, T.J., Sadraey, M.H., Belobaba, P., Cooper, J., and Seabridge, A. (2022). Introduction to UAV Systems, Wiley. [5th ed.]."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"11004","DOI":"10.1051\/shsconf\/202112911004","article-title":"The Global Drone Market: Main Development Trends","volume":"129","author":"Kapustina","year":"2021","journal-title":"SHS Web Conf."},{"key":"ref_3","unstructured":"Lee, H.C. (November, January 30). 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