Modelling fruit surface temperature by means of LiDAR 4D point clouds

During the last years, the occurrence of marked heat waves has increased as a consequence of climate change.
Such temperature hot spots can lead to sunburn at fruit surface.
By using remote sensing techniques, real-time fruit monitoring in orchards has proven to be a data source in adapting measures against triggers of heat damage, thus creating opportunities for risk models in orchard management.
Thereof, light detection and ranging (LiDAR) scanning provides geometric and radiometric information at fruit level by means of 3D point clouds.
By merging LiDAR scanning and thermal imaging, 4D point clouds including temperature annotation can describe the spatial temperature distribution.
Local temperature at the surface of the scanned apples was assessed by using a geometric modelling approach based on Fourier series expansion, thus expressing the apple geometry as a 2D surface in spherical coordinates.
The applicability of fruit data for constructing a heat transfer model to predict fruit surface temperature is discussed using LiDAR derived fruit information at given climate conditions and growing stage.
Influences due to direct and diffuse radiation at the fruit surface were observed as an increase in fruit surface temperature at specific locations in the orchard.

II International Symposium on Precision Management of Orchards and Vineyards

N. Tapia-Zapata, M. Zude-Sasse

4D point clouds, conduction, convection, heat transfer, LiDAR, radiation

https://doi.org/10.17660/ActaHortic.2024.1395.57