{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,29]],"date-time":"2026-04-29T14:53:28Z","timestamp":1777474408185,"version":"3.51.4"},"reference-count":36,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2019,6,12]],"date-time":"2019-06-12T00:00:00Z","timestamp":1560297600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100003725","name":"National Research Foundation of Korea","doi-asserted-by":"publisher","award":["NRF-2018R1A2A1A05078628"],"award-info":[{"award-number":["NRF-2018R1A2A1A05078628"]}],"id":[{"id":"10.13039\/501100003725","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>In this paper, we propose PPAP, an augmented reality platform with an actuated projector for dynamic user-perspective projection. In PPAP, a stationary camera is used jointly with a pan\u2013tilt motorized projector-camera unit. With the servo control of the steerable pan\u2013tilt system, the system is able to continuously orient itself to match the user\u2019s view center of the projection-mapped surface. This provides users with greatly widened viewing angles in the augmented scene, when compared to the stationary projection. Through user studies, in which users judged the size and distance of a projected virtual object, we verified that the perspective projection with the actuated projector helps users better understand the spatial relationship of the virtual object in the augmented scene in terms of depth perception.<\/jats:p>","DOI":"10.3390\/s19122652","type":"journal-article","created":{"date-parts":[[2019,6,12]],"date-time":"2019-06-12T10:55:19Z","timestamp":1560336919000},"page":"2652","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["PPAP: Perspective Projection Augment Platform with Pan\u2013Tilt Actuation for Improved Spatial Perception"],"prefix":"10.3390","volume":"19","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-1248-292X","authenticated-orcid":false,"given":"JungHyun","family":"Byun","sequence":"first","affiliation":[{"name":"Department of Computer Science, Yonsei University, Yonsei-ro 50, Seodaemun-gu, Seoul 03722, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Tack-Don","family":"Han","sequence":"additional","affiliation":[{"name":"Department of Computer Science, Yonsei University, Yonsei-ro 50, Seodaemun-gu, Seoul 03722, Korea"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2019,6,12]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","unstructured":"Bimber, O., and Raskar, R. 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