title: Digital sun sensor multi-spot operation.
abstract: 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.
authors: Department of Aerospace Engineering, University of Naples "Federico II", Piazzale Tecchio 80, 80125 Naples, Italy. giancarlo.rufino@unina.it
authors: Giancarlo
authors: G
authors: Rufino
authors: Michele
authors: M
authors: Grassi
mesh_terms: D006801:Humans; D007091:Image Processing, Computer-Assisted; D011856:Radiographic Image Enhancement; D016082:Solar System; D013472:Sunlight