Last generation instrument for agriculture multispectral data collection

Abstract

In recent years, the acquisition and analysis of multispectral data are gaining a growing interest and importance in agriculture.  On the other hand, new technologies are opening up for the possibility of developing and implementing sensors with relatively small size and featuring high technical performances.  Thanks to low weights and high signal to noise ratios, such sensors can be transported by different types of means (terrestrial as well as aerial vehicles), giving new opportunities for assessment and monitoring of several crops at different growing stages or health conditions.  The choice and specialization of individual bands, within the electromagnetic spectrum ranging from the ultraviolet to the infrared, plays a fundamental role in the definition of the so-called vegetation indices (eg. NDVI, GNDVI, SAVI, and dozens of others), posing new questions and challenges in their effective implementation.  The present paper firstly discusses the needs of low-distance-based sensors for indices calculation and then focuses on development of a new multispectral instrument, namely MAIA, specially developed for agricultural multispectral analysis.  Such instrument features high frequency and high resolution imaging through nine different sensors (1 RGB and eight monochromes with relative band-pass filters, covering the range from 390 to 950 nm).  The instrument allows synchronized multiband imaging owing to integrated global shutter technology, with a frame rate up to 5 Hz, and the exposure time can be as low as 1/5000 s.  An applicative case study is eventually reported on an area featuring different materials (organic and non-organic), to show potential of the new instrument.