Lucas Gabryel Maciel dos Santos

Mr. Lucas Gabryel Maciel dos Santos

orcid

Research Focus & Metrics

Academic Career Length

2Years (2025-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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3 October 2025 in Agriengineering
Verified
Journal Article
Open access
PDF file
Lucas SantanaLucas Santana
Lucas Santana
LSLucas Gabryel Maciel dos Santos
Lucas Gabryel Maciel dos Santos
JSJosiane Maria da Silva
Josiane Maria da Silva
Aldir Carpes Marques FilhoAldir Carpes Marques Filho
Aldir Carpes Marques Filho
FRANCESCO TOSCANOFRANCESCO TOSCANO
FRANCESCO TOSCANO
MZMarco Antonio Zanella
Marco Antonio Zanella
Driving wheel slippage in agricultural tractors is influenced by soil moisture, density, and penetration resistance. These surface variations reflect post-tillage composition, enabling dynamic mapping via Remotely Piloted Aircraft (RPAs). This study evaluated ballast recommendations based on soil surface data and slippage percentages, correlating added wheel weights at different speeds for a tractor-reversible plow system. Six 94.5 m2 quadrants were analyzed for slippage monitored by RPA (Mavic3M-RTK) pre- and post-agricultural operation overflights and soil sampling (moisture, density, penetration resistance). A 2 × 2 factorial scheme (F-test) assessed soil-surface attribute correlations and slippage under varying ballasts (52.5–57.5 kg/hp) and speeds. Results showed slippage ranged from 4.06% (52.5 kg/hp, fourth reduced gear) to 11.32% (57.5 kg/hp, same gear), with liquid ballast and gear selection significantly impacting performance in friable clayey soil. Digital Elevation Model (DEM) and spectral indices derived from RPA imagery, including Normalized Difference Red Edge (NDRE), Normalized Difference Water Index (NDWI), Bare Soil Index (BSI), Green–Red Vegetation Index (GRVI), Visible Atmospherically Resistant Index (VARI), and Slope, proved effective. The approach reduced tractor slippage from 11.32% (heavy ballast, 4th gear) to 4.06% (moderate ballast, 4th gear), showing clear improvement in traction performance. The integration of indices and slope metrics supported ballast adjustment strategies, particularly for secondary plowing operations, contributing to improved traction performance and overall operational efficiency.

6 October 2025 in Eng
Verified
Journal Article
Open access
PDF file
Lucas SantanaLucas Santana
Lucas Santana
LSLucas Gabryel Maciel dos Santos
Lucas Gabryel Maciel dos Santos
JSJosiane Maria da Silva
Josiane Maria da Silva
LCLuiz Alves Caldeira
Luiz Alves Caldeira
MLMarcos David Lopes
Marcos David Lopes
Gabriel Araujo e Silva FerrazGabriel Araujo e Silva Ferraz
Gabriel Araujo e Silva Ferraz
Efficient irrigation management is crucial for optimizing crop development while minimizing resource use. This study aimed to assess the spatial variability of water distribution under conventional sprinkler irrigation, alongside soil moisture and infiltration dynamics, using multispectral sensors onboard Remotely Piloted Aircraft (RPAs). The experiment was conducted over a 466.2 m2 area equipped with 65 georeferenced collectors spaced at 3 m intervals. Soil data were collected through volumetric rings (0–5 cm), auger sampling (30–40 cm), and 65 measurements of penetration resistance down to 60 cm. Four RPA flights were performed at 20 min intervals post-irrigation to generate NDVI and NDWI indices. NDWI values decreased from 0.03 to −0.02, indicating surface moisture reduction due to infiltration and evaporation, corroborated by gravimetric moisture decline from 0.194 g/g to 0.191 g/g. Penetration resistance exceeded 2400 kPa at 30 cm depth, while bulk density ranged from 1.30 to 1.50 g/cm3. Geostatistical methods, including Inverse Distance Weighting and Ordinary Kriging, revealed non-uniform water distribution and subsurface compaction zones. The integration of spectral indices within situ measurements proved effective in characterizing irrigation system performance, offering a robust approach for calibration and precision water management.

29 January 2025 in Proceedings of the Indian National Science Academy
Verified
Journal Article
Closed access
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DSDaniela Fonseca Melo de Souza
Daniela Fonseca Melo de Souza
LSLucas Gabryel Maciel dos Santos
Lucas Gabryel Maciel dos Santos
MBMarcos Eli Buzanskas
Marcos Eli Buzanskas
JSJeanne Broch Siqueira
Jeanne Broch Siqueira
FIFabio Iared
Fabio Iared
TMThiago Vasconcelos Melo
Thiago Vasconcelos Melo

4 May 2026 in Journal of Food Measurement and Characterization
Verified
Journal Article
Open access
Lucas SantanaLucas Santana
Lucas Santana
JSJosiane Maria da Silva
Josiane Maria da Silva
Gabriel Araujo e Silva FerrazGabriel Araujo e Silva Ferraz
Gabriel Araujo e Silva Ferraz
MSMozarte Santos Santana
Mozarte Santos Santana
LSLucas Gabryel Maciel dos Santos
Lucas Gabryel Maciel dos Santos
GBGianluca Bambi
Gianluca Bambi
Coffee fruit drying is an essential step, as it directly affects the drink’s final quality. The presence of green fruits in this process significantly reduces the quality standard. Conventional characterization techniques are performed manually, are time-consuming, and lead to increased estimation errors. Thus, the objective was to identify green, red, and black fruits in the drying patio by digital classification of multispectral and RGB images. The data were obtained by remotely piloted aircraft during daily flights over coffee fruits for eight days of drying. The analyses involved color segregation techniques, supervised classification (Random Forest), and the application of thirty vegetation indices to RGB and multispectral images, utilizing Python, RStudio, and GIS to generate statistical models and maps, in conjunction with manual fruit estimation and monitoring of temperature and humidity. The use of aerial images proved effective in monitoring colors only during the first three days, due to rapid moisture loss. In all analyses, green fruits showed better spectral separation. Image segmentation proved to be the superior method, adequate up to the third day. Random Forest showed reduced performance due to shadows and color mixing and was only effective on the first day. Among the RGB indices, ExGR and MGRVI stood out, with high potential for detecting green fruits, while TGI indicated two classes of green, highlighting the efficiency of conventional sensors. For multispectral images, NDVI was effective on the first day, and NDWI was effective up to the third day, influenced by fruit of humidity reduction. The need to develop a specific vegetative index to standardize this monitoring is emphasized, based on green separation, considering humidity and robust quality indicators.

23 June 2026 in Agriengineering
Verified
Journal Article
Open access
PDF file
LSLucas Gabryel Maciel dos Santos
Lucas Gabryel Maciel dos Santos
Lucas SantanaLucas Santana
Lucas Santana
MLMarcos David Lopes
Marcos David Lopes
JSJosiane Maria da Silva
Josiane Maria da Silva
CSCarmem Lúcia da Silva Surmani
Carmem Lúcia da Silva Surmani
APAndrea Pagliai
Andrea Pagliai
Digital Elevation Models (DEMs) provide essential information for decision-making in precision agriculture. This study evaluated the altimetric quality of DEMs generated by Remotely Piloted Aircraft (RPA) platforms, the influence of flight direction, and the effect of mechanically disturbed soil surface conditions. We obtained data from a 900 m2 area. Flights were conducted under pre- and post-mechanization conditions using a reversible plow, with flights in both longitudinal and transverse directions. We processed images using Structure-from-Motion (SfM) techniques to generate dense point clouds and DEMs. Statistical analyses relied on raster statistics and elevation cross-section transects of microtopography, were evaluated via descriptive statistics, ANOVA, Tukey’s HSD tests, and spatialization with micro-variation classification. Significant differences emerged among the evaluated models (p < 0.001), with Phantom-derived DEMs showing systematically higher elevations than Mavic models (617.31 ± 0.16 m vs. 605.41 ± 0.23 m, respectively). Post-plowing longitudinal flights showed the least variation, indicating greater altimetric consistency after secondary soil preparation. Conversely, the pre-plowing transverse flight (Mavic Flight 2) produced the largest errors. Quantitative assessment of topographic profiles revealed high morphological correspondence between platforms, with Pearson correlation coefficients ranging from 0.84 to 0.96 after vertical normalization, confirming that terrain morphology was preserved despite systematic vertical offsets. The effect of flight direction was more pronounced before soil preparation; after harrowing (a homogeneous surface), the difference between directions decreased, but longitudinal flights maintained an advantage, while transverse flights (especially Mavic) tended to overestimate elevations spatially.