Optical fiber sensors for detecting spraying drift in drone agricultural applications
Chemical pesticides drone spraying is becoming increasingly available due to its advantages such as autonomy and fast operation. A major consideration that currently limits widespan application of the technique is the undesirable drift of the spraying cloud in neighboring areas. Herein we propose the use of optical fiber long period gratings (LPGs) of extended length (~9cm) as line sensors for tracing spraying droplet distribution. Preliminary results indicate a linear trend between particle density and LPG wavelength shift and extinction ratio change. Indicatively, for a coverage of 3.9 droplets/mm2 the corresponding LPG strength and wavelength changes are 1.3dB and 65pm, respectively.
Foundation for Research and Technology-Hellas (Greece)