STATISTICAL EVALUATION OF ULTRASONIC SIGNAL DIFFERENCES DEPENDENT ON THE ANGLE OF TILT OF THE REFLECTING SURFACE

This paper deals with the statistical evaluation of the variation of amplitudes measured on ultrasonic transducers, which were parabolic displaced. The reflecting surface was used metal plate of dimensions 245x220x1 millimetres. The distance of the ultrasonic transmitter from the reflection normal was set conically to 190 mm. The distance of the ultrasonic of the transducers from the reflection normal was 900 mm. At the significance level of α = 0.05, it was shown that there is a statistically significant decrease in absolute amplitude with increasing angle of the reflection normal on the ultrasound transducers. The critical angle was set to be 30°, which supports the chosen angular limit at the -6 dB attenuation band for the ultrasonic transducer used. Significant differences in the amplitudes of the ultrasonic signals give an indication of the direction of tilt of the reflecting surface. The statistically observed differences between the ultrasonic signal amplitudes are more indicative than the attenuation criteria of -3 dB and -6 dB, respectively. The mean values of the signal amplitudes were determined by arithmetic averaging over four repetitions of the experiment. The normality of the distribution of the detected signal amplitudes was verified at a significance level of α = 0.05 by the Shapiro-Wilk test

INFLUENCE OF CONTROL ALGORITHM ON DRIVE CONSUMPTION OF WHEELED MOBILE ROBOT

In field of autonomous mobile robotics, the quality of control is a crucial aspect. Besides the precision of control, the energy consumption for motion is becoming an increasingly demanding characteristic of a controller due to the increasing costs of fossil fuels and electricity. We created a simulation model of a differential drive mobile robot motion in a vineyard row including robot dynamics for evaluating motion consumption and implemented commonly used PID, fuzzy, and LQ control algorithms. Their task was to navigate the robot through the middle of the vineyard row section by measuring distances from trellises on both sides of the robot. The comparison was carried out using MATLAB software and the best results both in terms of power consumption and control accuracy were achieved by LQI controller. The designed model for navigating the robot through the centre of the vineyard row and optimized controllers will be implemented in a real robot and tested in a real scenario

The Effect of Azimuth and Tilt Angle Changes on the Energy Balance of Photovoltaic System Installed in the Southern Slovakia Region

Energy balance of the photovoltaic system is influenced by many factors. In this article the effect of tilt and azimuth angle changes of the photovoltaic system energy production is analyzed. These parameters have significant impact on the amount of solar radiation which hits on the photovoltaic panel surface and therefore also on the energy absorbed by the module surface. The main aim of research was identification of the optimal position of photovoltaic system installation in the southern Slovakia regions. The experimental apparatus had two setups consisting of polycrystalline photovoltaic modules. The first setup was used for identification of the tilt angle changes in the range (0–90°). The second one was focused on the detection of the azimuth angle effect to the energy production. The measurement results were statistically processed and mathematically analyzed. Obtained dependencies are presented as two-dimensional and three-dimensional graphical relations. Regression equations characterize time relations between the tilt or azimuth angle and the energy produced by the photovoltaic system in Southern Slovakia. Obtained simplified mathematical model was verified by analytical model. Presented models can be used for the dimensioning and optimization of the photovoltaic system energy production

Nutritional, Antioxidant, Sensory, Energetic, and Electrical Properties of Enriched Pasta

The aim of the presented study was to determine the nutritional properties (dry matter, total protein, ash, and selected amino acid content), antioxidant properties (antioxidant activity; total polyphenol, flavonoid, and phenolic acid content; total carotenoid, chlorophyll, and anthocyanin), and sensory profile (general appearance, flavor, taste, aftertaste, overall acceptability) of pasta enriched with powdered nettle leaves, elderberry fruit, and carrot in additions of 3%. A control variant without the addition of plant material was prepared for comparison of the results. Two of our samples of pasta (with nettle and carrot) had lower calorific values by approximately 17%. However, the energy value of the pasta was not significantly affected by added substances. Electrical properties (resistance, impedance) were also measured, and resistivity was calculated. We found that impedance and resistivity were influenced by added components in pasta. In the frequency range from 20 kHz to 100 kHz, we were able to use the measured dependencies of the mentioned electrical properties to identify the type of addition to the pasta. Correlations exist between the electrical properties and nutritional properties of enriched pasta samples, and could be used to indetify value-added pasta in processing chain digitalization