{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T18:13:14Z","timestamp":1780337594629,"version":"3.54.1"},"reference-count":23,"publisher":"MDPI AG","issue":"6","license":[{"start":{"date-parts":[[2009,6,9]],"date-time":"2009-06-09T00:00:00Z","timestamp":1244505600000},"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>This paper describes the high precision digital sun sensor under development at the University of Naples. The sensor determines the sun line orientation in the sensor frame from the measurement of the sun position on the focal plane. It exploits CMOS technology and an original optical head design with multiple apertures. This allows simultaneous multiple acquisitions of the sun as spots on the focal plane. The sensor can be operated either with a fixed or a variable number of sun spots, depending on the required field of view and sun-line measurement precision. Multiple acquisitions are averaged by using techniques which minimize the computational load to extract the sun line orientation with high precision. Accuracy and computational efficiency are also improved thanks to an original design of the calibration function relying on neural networks. Extensive test campaigns are carried out using a laboratory test facility reproducing sun spectrum, apparent size and distance, and variable illumination directions. Test results validate the sensor concept, confirming the precision improvement achievable with multiple apertures, and sensor operation with a variable number of sun spots. Specifically, the sensor provides accuracy and precision in the order of 1 arcmin and 1 arcsec, respectively.<\/jats:p>","DOI":"10.3390\/s90604503","type":"journal-article","created":{"date-parts":[[2009,6,9]],"date-time":"2009-06-09T11:37:43Z","timestamp":1244547463000},"page":"4503-4524","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":26,"title":["Multi-Aperture CMOS Sun Sensor for Microsatellite Attitude Determination"],"prefix":"10.3390","volume":"9","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 Federico II, 80 Piazzale Tecchio, 80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Michele","family":"Grassi","sequence":"additional","affiliation":[{"name":"Department of Aerospace Engineering, University of Naples Federico II, 80 Piazzale Tecchio, 80125 Naples, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2009,6,9]]},"reference":[{"key":"ref_1","unstructured":"Hales, J.H., and Pedersen, M. (, January August). Two-axes MOEMS Sun Sensor for Pico Satellites. Logan, UT, USA."},{"key":"ref_2","unstructured":"Liebe, C.C., Alkalai, L., Domingo, G., Hancock, B., Hunter, D., Mellestrom, J., Ruiz, I., Sepulveda, C., and Pain, B. (,  2002). Micro APS Based Star Tracker. Big Sky, MT, USA."},{"key":"ref_3","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, Montana, USA."},{"key":"ref_4","unstructured":"Enright, G., and Enright, J. (, January May). Optimization of a Sun Sensor Illumination Pattern using Genetic Algorithms. Ottawa, ON, Canada."},{"key":"ref_5","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_6","unstructured":"Xie, N., Theuwissen, Albert J.P., Wang, X., Leijtens, J., Hakkesteegt, H., and Janse, H. (, January October). A CMOS Image Sensor with Row and Column Profiling Means. Lecce, Italy."},{"key":"ref_7","unstructured":"Monnini, E., Procopio, D., Alison, B., Ogiers, W., Innocent, M., Pritchard, A., and Airey, S. (, January June). System on Chip Development for Attitude Sensors. Tralee, Ireland."},{"key":"ref_8","unstructured":"Agostara, C., Dionisio, C., Di Salvo, A., and Guarrera, G. (, January December). MIOSAT Mission Analysis and Scenario Definition. ESA\/ESOC, Darmstadt, Germany."},{"key":"ref_9","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":"Buonocore","year":"2005","journal-title":"Acta Astronaut."},{"key":"ref_10","unstructured":"Rufino, G., Grassi, M., Pulcino, V., and Degtyarev, A. (, January April). A Micro Sun Sensor for Earth-Observation Nanosatellites Flying in Formation. Berlin, Germany."},{"key":"ref_11","unstructured":"Rufino, G., Perrotta, A., and Grassi, M. (April, January March). Laboratory Test of an APS-based Sun Sensor Prototype. Toulouse, France."},{"key":"ref_12","doi-asserted-by":"crossref","unstructured":"Wertz, J.R. (1978). Spacecraft Attitude Determination and Control, D. Reidel Publishing Company.","DOI":"10.1007\/978-94-009-9907-7"},{"key":"ref_13","unstructured":"Chum, J., and Vojta, J. (, January December). Wide Angle Digital Slit Sun Sensor using CCD Linear Array. Toulouse, France."},{"key":"ref_14","unstructured":"Liebe, C.C., and Mobasser, S. (, January March). MEMS Based Sun Sensor. Big Sky, Montana, USA."},{"key":"ref_15","unstructured":"Pratt, W.K. (1991). Digital Image Processing, John Wiley & Sons."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"359","DOI":"10.1016\/0893-6080(89)90020-8","article-title":"Multilayer Feedforward Neural Networks are Universal Approximators","volume":"2","author":"Hornik","year":"1989","journal-title":"Neural Networks"},{"key":"ref_17","unstructured":"Dreyfus, G. (2005). Neural Networks. Methodology and Applications, Springer-Verlag."},{"key":"ref_18","unstructured":"Rufino, G., Grassi, M., and Rolfi, D. (, January August). Preliminary Calibration Results For a High-Precision CMOS Sun Sensor. Honolulu, Hawaii, HI, USA."},{"key":"ref_19","unstructured":"Available online: www.lot-oriel.com."},{"key":"ref_20","unstructured":"Available online: www.labsphere.com."},{"key":"ref_21","unstructured":"Available online: www.pi.ws."},{"key":"ref_22","unstructured":"Rufino, G., Grassi, M., and Perrotta, A. (, January July). Development and Validation of a Modern CMOS Digital Sun Sensor at UniNa. Riomaggiore, Italy."},{"key":"ref_23","unstructured":"Helfrick, A.D., and Cooper, W.D. (1990). Modern Electronic Instrumentation and Measurement Techniques, Prentice Hall Inc."}],"container-title":["Sensors"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/1424-8220\/9\/6\/4503\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,11]],"date-time":"2025-10-11T22:10:32Z","timestamp":1760220632000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/1424-8220\/9\/6\/4503"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2009,6,9]]},"references-count":23,"journal-issue":{"issue":"6","published-online":{"date-parts":[[2009,6]]}},"alternative-id":["s90604503"],"URL":"https:\/\/doi.org\/10.3390\/s90604503","relation":{},"ISSN":["1424-8220"],"issn-type":[{"value":"1424-8220","type":"electronic"}],"subject":[],"published":{"date-parts":[[2009,6,9]]}}}