Drone-Based Fluorescence Lidar for Agricultural Applications

We developed ultracompact fluorescence LiDAR for agricultural applications. To minimize the device, we used laser diode (wavelength 405 nm and power consumption 150 mW) and minispectrometer with wavelength range from 350 nm to 810 nm. We used single board computer to control LiDAR instrument. Small size (10×15×5 cm) and low weight (310 g) of the LiDAR make it possible to install it on a commercial unmanned aerial vehicle (UAV). Maize field have been sensed by LiDAR to distinguish healthy and plants under stress. Due the measurement we constructed field maps in different wavelengths of fluorescent radiation

Drone-Based Fluorescence Lidar for Agricultural Applications

We developed ultracompact fluorescence LiDAR for agricultural applications. To minimize the device, we used laser diode (wavelength 405 nm and power consumption 150 mW) and minispectrometer with wavelength range from 350 nm to 810 nm. We used single board computer to control LiDAR instrument. Small size (10×15×5 cm) and low weight (310 g) of the LiDAR make it possible to install it on a commercial unmanned aerial vehicle (UAV). Maize field have been sensed by LiDAR to distinguish healthy and plants under stress. Due the measurement we constructed field maps in different wavelengths of fluorescent radiation

Improving Calibration Strategy for LIBS Heavy Metals Analysis in Agriculture Applications

A new calibration procedure, known as mapping conditional-calibration laser-induced breakdown spectroscopy (LIBS), has been suggested to improve analysis results for heterogeneous samples. The procedure is based on LIBS elemental mapping, followed by signal conditioning in every sampling spot to skip signal outliers, then by finalizing the calibration curve construction. The suggested mapping conditional calibration procedure was verified for zinc analysis in soybean grist samples. The laser parameters correspond to those of the hand-held LIBS instrument in order to estimate the influence of sample surface heterogeneity under on-site analysis conditions. The laser spot (60 μm) was equal to or smaller than the typical size of grist particles (40–500 μm) but laser crater dimensions were significantly greater and varied widely (150–450 μm). The LIBS mapping of different spectral signals (atomic and ionic lines for major and minor components) was achieved. Elemental maps were normalized to achieve signal maps that were conditionally spotted to skip signal outliers. It was demonstrated that the suggested mapping conditional-calibration LIBS provided 15 ppm RMSECV for zinc determination in heterogeneous samples, which is typical for agricultural products

Fluorescence Mapping of Agricultural Fields Utilizing Drone-Based LIDAR

A compact and low-weight LIDAR instrument has been developed for laser-induced fluorescence spectroscopy sensing of maize fields. Fluorescence LIDAR had to be installed on a small industrial drone so that its mass was <2 kg and power consumption was <5 W. The LIDAR instrument utilized a continuous wave diode laser (405 nm, 150 mW) for inducing fluorescence and a small spectrometer for backscattered photons acquisition. For field testing, the LIDAR instrument was installed on a quadcopter for remote sensing of plants in a maize field in three periods of the plant’s life. The obtained fluorescence signal maps have demonstrated that the average chlorophyll content is rather non-uniform over the field and tends to increase through the plant vegetation cycle. Field tests proved the feasibility and perspectives of autonomous LIDAR sensing of agricultural fields from drones for the detection and location of plants under stress

Smartphone Based Fluorescence Imaging for Online Control of Cattle Fodder Preparation

A simple and cost-effective technique has been suggested for online monitoring of grist concentration in fodder. The technique is based on fluorescence imaging with grow light lamp excitation and a consumer CMOS camera (DSLR or smartphone) for photo capturing. A prototype instrument has been developed and tested in the laboratory for quantitative express determination of rapeseed grist concentration in fodder. In situ measurement of grist concentration during cattle food preparation has been demonstrated, and the perspectives were discussed. The developed instrument has the potential to ensure more accurate preparation of individual cattle diets compared to currently available methods, which will improve the efficiency of the cattle food production

Fossil Plant Remains Diagnostics by Laser-Induced Fluorescence and Raman Spectroscopies

Fossilized plant remains have been studied simultaneously by laser induced fluorescence and Raman spectroscopies, to reveal the prospective methods for onsite or/and laser remote sensing in future extraterrestrial missions. A multiwavelength instrument, capable of fluorescence and Raman measurements, has been utilized for the study of isolated plant fossils, as well as fossils associated with sedimentary rocks. Laser-induced fluorescence spectroscopy revealed that plant fossils and rocks’ luminosity differed significantly due to chlorophyll derivatives (chlorin, porphyrins, lignin components etc.); therefore, fossilized plants can be easily detected at rock surfaces onsite. Raman spectroscopy highly altered the fossilized graphitic material via the carbon D and G bands. Our results demonstrated that combined laser-induced fluorescence and Raman spectroscopy measurements can provide new insights into the detection of samples with biogenicity indicators such as chlorophyll and its derivatives, as well as kerogenous materials. The prospects of multiwavelength LIDAR instrument studies under fieldwork conditions are discussed for fossils diagnostics. The method of laser remote sensing can be useful in geological exploration in the search for oil, coal-bearing rocks, and rocks with a high content of organic matter

Using Fluorescence Spectroscopy to Detect Rot in Fruit and Vegetable Crops

The potential of the method of fluorescence spectroscopy for the detection of damage and diseases of fruits and vegetables was studied. For this purpose, the spectra of fluorescence of healthy and rotten apples and potatoes have been investigated. Excitation of samples was carried out using a continuous semiconductor laser with a wavelength of 405 nm and a pulsed solid-state laser with a wavelength of 527 nm. Peaks in the region of 600–700 nm in rotten samples were shifted towards shorter wavelengths for most samples in both modes of spectroscopy. The differences in the fluorescence spectra of a healthy and rotten apple surface have been revealed to be in the spectral range of 550–650 nm for 405 nm continuous excitation. When exposed to a laser in a pulsed mode (527 nm), the contribution of the 630 nm peak in the spectrum increases in rotten samples. The observed differences make it possible to use this method for separating samples of healthy and rotten fruits and vegetables. The article paid attention to the influence of many factors such as sample thickness, time after excitation, contamination by soil and dust, cultivar, and location of the probing on fluorescence spectra

Using Fluorescence Spectroscopy to Detect Rot in Fruit and Vegetable Crops

The potential of the method of fluorescence spectroscopy for the detection of damage and diseases of fruits and vegetables was studied. For this purpose, the spectra of fluorescence of healthy and rotten apples and potatoes have been investigated. Excitation of samples was carried out using a continuous semiconductor laser with a wavelength of 405 nm and a pulsed solid-state laser with a wavelength of 527 nm. Peaks in the region of 600&ndash;700 nm in rotten samples were shifted towards shorter wavelengths for most samples in both modes of spectroscopy. The differences in the fluorescence spectra of a healthy and rotten apple surface have been revealed to be in the spectral range of 550&ndash;650 nm for 405 nm continuous excitation. When exposed to a laser in a pulsed mode (527 nm), the contribution of the 630 nm peak in the spectrum increases in rotten samples. The observed differences make it possible to use this method for separating samples of healthy and rotten fruits and vegetables. The article paid attention to the influence of many factors such as sample thickness, time after excitation, contamination by soil and dust, cultivar, and location of the probing on fluorescence spectra