Denis Stajnko

Estimation of number and diameter of apple fruits in an orchard during the growing season by thermal imaging

Abstract A new method for estimating the number of apple fruits and measuring their diameter in the orchard was developed and tested. A thermal camera captured images of apple trees five times during the vegetation period June–September 2001. Each time 120 images of twenty apple trees were recorded late in the afternoon to achieve a temperature gradient between fruits and their background. Recorded images were processed using several image processing algorithms. Correlation coefficients R 2 from 0.83 to 0.88 were established between the manually measured fruit number and the estimated number based on a fruit detection algorithm. According to fruit development and the established growing curve, the value of the correlation coefficient, R 2 , increased during the ripening period. For measuring the fruits diameter values of R 2 between 0.68 and 0.70 were established. These slightly increased according to the fruits colour and size development during the ripening period.

Programmable Ultrasonic Sensing System for Targeted Spraying in Orchards

This research demonstrates the basic elements of a prototype automated orchard sprayer which delivers pesticide spray selectively with respect to the characteristics of the targets. The density of an apple tree canopy was detected by PROWAVE 400EP250 ultrasound sensors controlled by a Cypress PSOC CY8C29466 microcontroller. The ultrasound signal was processed with an embedded computer built around a LPC1343 microcontroller and fed in real time to electro-magnetic valves which open/close spraying nozzles in relation to the canopy structure. The analysis focuses on the detection of appropriate thresholds on 15 cm ultrasound bands, which correspond to maximal response to tree density, and this was selected for accurate spraying guidance. Evaluation of the system was performed in an apple orchard by detecting deposits of tartrazine dye (TD) on apple leaves. The employment of programmable microcontrollers and electro-magnetic valves decreased the amount of spray delivered by up to 48.15%. In contrast, the reduction of TD was only up to 37.7% at some positions within the tree crown and 65.1% in the gaps between trees. For all these reasons, this concept of precise orchard spraying can contribute to a reduction of costs and environmental pollution, while obtaining similar or even better leaf deposits.

Design and testing of an automated system for targeted spraying in orchards

The research aims to demonstrate the basic system elements of a prototype automated orchard sprayer, which can deliver pesticide spray selectively with respect to the characteristics of the targets. The shape of the apple tree canopy was detected by a machine vision system using an RGB camera and appropriate image analysis. Information captured by RGB camera and processed by specific software was fed in real-time to a spraying arm, with three individually controlled sections, which adapt the pesticide spray flow to the canopy shape. The system allows variation in the liquid flow rate and volume of chemicals by means of controlled electric valves, whereby the amount of spray depends on the shape of the tree crowns. The current project focuses on developing the critical elements for spraying an individual tree and evaluates them in independent field experiments with the use of water sensitive papers (WSP). The demonstrated concept of precise application of pesticide sprays supports decreasing of the amount of delivered spray, thereby reducing both costs and environmental pollution.ZusammenfassungDie Untersuchungen sollen grundlegende System-Elemente des Prototyps eines automatisierten Sprühgerätes darstellen, das geeignet ist, Pflanzenschutzmittel gezielt auf Zielobjekte auszubringen. Als Entscheidungs- und Steuerungselement wurde ein „Machine-vision-system” mit RGB-Kamera und nachfolgender Bildanalyse entwickelt und eingesetzt. Die Bildinformationen wurden in Echtzeit genutzt, um die drei verstellbaren Sprüheinheiten individuell hinsichtlich Ausbringmenge entsprechend der Kronenform zu steuern. Das System ermöglicht durch elektromagnetisch gesteuerte Ventile die Ausbringmenge entsprechend der Baumkronenform anzupassen. Das Projekt konzentrirt sich auf die Enwicklung der kritischen Elemente des Sprühgerätes zum Besprühung von einzelne Silhouetten in der Baumreihe. Das vorgestellte Konzept der genauen Anwendung von Pestiziden direkt auf die Baumkronen ist geeignet, die ausgebrachte Produktmenge und damit gleichzeitig auch Kosten und Umweltbelastungen zu reduzieren.

Development of alternative plant protection product application techniques in orchards, based on measurement sensing systems

Sustainable application is a way to reduce harmful influence to the living environment.The establishment of an appropriate PPP dose expression in crop protection.Sensing systems for electronic canopy characterization.Decision-making models for controlling the dosage of PPP with the use of special algorithms. The development of alternative plant protection product (hereinafter PPP) application techniques in recent decades has been based on various principles of sprayer operation. So far, several researchers have tried with partial success to find a compromise (a uniform standard) to ensure continuous PPP application to selected tree canopies in an orchard. Researchers have offered certain solutions for controlling dosage rates of PPP, based on special measurement systems and decision-making models to optimize the dosage rate of PPP. With sensing systems for electronic canopy characterization, which originally functioned on the basis of ultrasound waving and later on the principle of spectral reflection, characteristics of tree canopies in an orchard could be adequately estimated. However, attention must be paid to the fact that discrepancies in the original measurement systems were too large, owing to imprecise operation of various sensor components. Nevertheless it is necessary to underline that advanced spectral laser technology is a strong tool for developers of alternative PPP application techniques, and with it, tree canopy properties are sensed in real time. So it is no longer a major problem in the precise application to establish the tree canopy properties, but to control artificial intelligence actuation, which in the future will properly direct the air flow and the dosage rate of PPP per tree canopy in the orchard.

Polar Sport Tester for Cattle Heart Rate Measurements

Well-being and health status of the animal in relations to achieving optimal production, become a standard when grading intensive livestock systems. Heart rate and body temperature have traditionally been used as parameters for different animal species health assessment, since they can indicate a problem with the animal. Also, interest for stressrelated research increased in the last decades, resulting in many available techniques, but as stated by (Janczarek, 2009) the simplicity and practical applicability for the average user should be taken into account. According to (Hopster, 1998; Janzekovic, 2005; Aerts et al., 2008) the change of heart rate can be a relevant parameter, when studying the response of the animal to stress. This is in correlation with findings in the humane medicine that variability of the heart rate serves as an important mechanism of the adaptation capability. Reaction of heart is viewed as an objective way of representing the autonomous responses of the nervous system to psychological stressors, associating increased and decreased heart rates with the predominant influence of sympathetic or parasympathetic nervous systems. Challenges of the environment activate both branches of the autonomous nervous system. This induces changes in the frequency of the heart rate, which is viewed as the index of the psychological influence of outside events (Herd, 1991). Recent findings also demonstrated direct hard-wired linkage between control of cardiac function and animal response (Lefcourt et al., 1999). Most important stimuli for variations in heart rate generally are excitement, stress, exercise, or some kind of altered physical homeostasis. Because of this, focus in research has always been to investigate and monitor changes in the mentioned parameters, aiming to get a strong correlation with health status. This resulted in invention of special devices which rely on heart rate as certainly the most practical means for judging animal’s status. Heart rate monitors have been developed for purpose of fitness in human and equine athletes, but have evolved into modern health status measuring devices. This equipment became recommended and highly advocated tool in illness, disease, or stress diagnostics. Because of accuracy of measurements with Polar Sport Tester (best accuracy in comparison with ECG) (Macfarlane et al., 1989; Hopster & Blokhuis, 1994; Lefcourt et al., 1999) the said finding was taken into account to a greater extent in the analysis of the data of our test.