{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T18:12:08Z","timestamp":1780337528894,"version":"3.54.1"},"reference-count":19,"publisher":"MDPI AG","issue":"12","license":[{"start":{"date-parts":[[2012,11,28]],"date-time":"2012-11-28T00:00:00Z","timestamp":1354060800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/3.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>The operation and test of a multi-spot digital sun sensor for precise sun-line determination is described. The image forming system consists of an opaque mask with multiple pinhole apertures producing multiple, simultaneous, spot-like images of the sun on the focal plane. The sun-line precision can be improved by averaging multiple simultaneous measures. Nevertheless, the sensor operation on a wide field of view requires acquiring and processing images in which the number of sun spots and the related intensity level are largely variable. To this end, a reliable and robust image acquisition procedure based on a variable shutter time has been considered as well as a calibration function exploiting also the knowledge of the sun-spot array size. Main focus of the present paper is the experimental validation of the wide field of view operation of the sensor by using a sensor prototype and a laboratory test facility. Results demonstrate that it is possible to keep high measurement precision also for large off-boresight angles.<\/jats:p>","DOI":"10.3390\/s121216451","type":"journal-article","created":{"date-parts":[[2012,11,28]],"date-time":"2012-11-28T11:03:39Z","timestamp":1354100619000},"page":"16451-16465","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Digital Sun Sensor Multi-Spot Operation"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-6353-5219","authenticated-orcid":false,"given":"Giancarlo","family":"Rufino","sequence":"first","affiliation":[{"name":"Department of Aerospace Engineering, University of Naples \u201cFederico II\u201d, Piazzale Tecchio 80, 80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michele","family":"Grassi","sequence":"additional","affiliation":[{"name":"Department of Aerospace Engineering, University of Naples \u201cFederico II\u201d, Piazzale Tecchio 80, 80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2012,11,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"975","DOI":"10.1016\/S0094-5765(03)00079-1","article-title":"Design, development and test of the attitude control subsystem for an earth observation microsatellite","volume":"52","author":"Pastena","year":"2003","journal-title":"Acta Astronaut"},{"key":"ref_2","doi-asserted-by":"crossref","unstructured":"Accardo, D., Rufino, G., Esposito, F., Pitter\u00e0, T., and Grassi, M. (2009, January 6\u20139). Design and Development of a Facility for Real-Time Tests of Star Tracker Algorithms. Seattle, WA, USA. Paper AIAA-2009-1835.","DOI":"10.2514\/6.2009-1835"},{"key":"ref_3","doi-asserted-by":"crossref","unstructured":"Rufino, G., Grassi, M., Esposito, F., and Paltro, D. (2009, January 6\u20139). Real-Time Performance Analysis of the Unina APS-Based Micro Sun Sensor. Seattle, WA, USA. Paper AIAA-2009-1838.","DOI":"10.2514\/6.2009-1838"},{"key":"ref_4","unstructured":"Liebe, C.C., Mobasser, S., Bae, Y., Wrigley, C.J., Shroeder, J.R., and Howard, A.M. (, January March). Micro Sun Sensor. Big Sky, MA, USA."},{"key":"ref_5","unstructured":"Enright, G., and Enright, J. (2006, January 7\u201310). Optimization of a Sun Sensor Illumination Pattern Using Genetic Algorithms. Ottawa, ON, Canada."},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"2494","DOI":"10.1088\/0957-0233\/17\/9\/017","article-title":"Digital sun sensor based on the optical vernier measuring principle","volume":"17","author":"Chen","year":"2006","journal-title":"Meas. Sci. Technol"},{"key":"ref_7","doi-asserted-by":"crossref","unstructured":"Xie, N., Theuwissen, A.J.P., Wang, X., Leijtens, J., Hakkesteegt, H., and Janse, H. (2008, January 26\u201329). A CMOS Image Sensor with Row and Column Profiling Means. Lecce, Italy.","DOI":"10.1109\/ICSENS.2008.4716697"},{"key":"ref_8","unstructured":"Monnini, E., Procopio, D., Alison, B., Ogiers, W., Innocent, M., Pritchard, A., and Airey, S. (2008, January 2\u20135). System on Chip Development for Attitude Sensors. Tralee, Ireland."},{"key":"ref_9","unstructured":"Agostara, C., Dionisio, C., Di Salvo, A., and Guarrera, G. (, January December). MIOSAT Mission Analysis and Scenario Definition. Darmstadt, Germany."},{"key":"ref_10","doi-asserted-by":"crossref","unstructured":"Grassi, M., Rufino, G., and Rolfi, D. (2006, January 2\u20136). Unina Micro Sun Sensor as Technology Demonstration Payload. Valencia, Spain. Volume 7.","DOI":"10.2514\/6.IAC-06-C1.P.2.01"},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1016\/j.actaastro.2004.09.006","article-title":"Aps-based miniature sun sensor for earth observation nanosatellites","volume":"56","author":"Bonocore","year":"2005","journal-title":"Acta Astronaut"},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"4503","DOI":"10.3390\/s90604503","article-title":"Multi-aperture CMOS sun sensor for microsatellite attitude determination","volume":"9","author":"Rufino","year":"2009","journal-title":"Sensors"},{"key":"ref_13","unstructured":"Rufino, G., Grassi, M., and Rolfi, D. (October, January 29). Calibration Results of a Novel Micro Sun Sensor for Nanosatellite Attitude Determination. Glasgow, Scotland, UK."},{"key":"ref_14","unstructured":"Rufino, G., Perrotta, A., and Grassi, M. (2004). Laboratory Test of an APS-Based Sun Sensor Prototype, European Space Agency. (Special Publication) ESA SP (554),."},{"key":"ref_15","doi-asserted-by":"crossref","unstructured":"Rufino, G., Grassi, M., Pulcino, V., and Degtyarev, A. (2005, January 4\u20138). A Micro Sun Sensor for Earth-Observation Nanosatellites Flying in Formation. Berlin, Germany.","DOI":"10.1515\/9783110919806.353"},{"key":"ref_16","doi-asserted-by":"crossref","unstructured":"Rufino, G., Grassi, M., and Rolfi, D. (2008, January 18\u201321). Preliminary Calibration Results for a High-Precision CMOS Sun Sensor. Honolulu, HI, USA. paper AIAA 2008-7319.","DOI":"10.2514\/6.2008-7319"},{"key":"ref_17","unstructured":"Rufino, G., and Grassi, M. (October, January 27). Mission-oriented Micro-Sun-Sensor Laboratory Testing in Real-Time Operation Mode. Prague, Czech Republic."},{"key":"ref_18","unstructured":"Rufino, G., and Grassi, M. (2012, January 19\u201321). Micro Sun Sensor Perfomance Validation in Ground Reproduced Orbital Conditions. Porto, Portugal."},{"key":"ref_19","unstructured":"(2010). Neural Network Matlab User Guide, 2010 Version, The MathWorks, Inc."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/12\/16451\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T21:53:53Z","timestamp":1760219633000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/12\/12\/16451"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2012,11,28]]},"references-count":19,"journal-issue":{"issue":"12","published-online":{"date-parts":[[2012,12]]}},"alternative-id":["s121216451"],"URL":"https:\/\/doi.org\/10.3390\/s121216451","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2012,11,28]]}}}