The paper presents a surface flatness control system designed for installation on a production line. Such a system allows the control of all blanks leaving the production line in terms of measuring ...flatness made in the conditions prevailing on the production line. The article discusses 3D imaging methods enabling the construction of a surface image. An analysis of imaging parameters for each method is presented. For the selected imaging method, an analysis of the imaging resolution is presented. An example of flatness measurement for a selected element after a welding operation is shown. The flatness measurement algorithm is discussed, and the results of measurements are presented. The results of measurements for selected two product groups are presented.
It is known that the use of alternative fuels leads to changes in the operating parameters of internal combustion engines, and the nature of the changes in most cases is not known. Therefore, the ...question of researching the main operating indicators of the internal combustion engine supplied with RME B100 biodiesel fuel is important, and the results will help to eliminate or reduce negative factors that can lead to the deterioration of the operational and technical indicators of the internal combustion engine. The purpose of the research was to develop an experimental research facility using appropriate equipment and to study the main operational and technical parameters of the air-cooled D21A1 diesel engine on RME B100 biodiesel fuel. To reach the goal, the following tasks were formulated: the development of a test facility and research on the main technical and operational performance indicators of the D21A1 diesel engine on RME B100 biodiesel fuel. The authors’ previous research results were applied in the setting of the D21A1 test engine in the process of RME B100 biodiesel research; namely, to achieve maximum fuel combustion efficiency, the injection moment was increased by 6°. The results ensured the maximum efficiency of using RME B100 biodiesel in engines without making changes to the design of the latter. System analysis and the comparison method were used during the research. In the process of using RME B100 biodiesel fuel on the air-cooled D21A1 engine, we found a decrease in engine torque of 6.5%; a decrease in effective power of 6.7%; a growth in specific effective fuel consumption of up to 22.3%; and an increase in hourly fuel consumption of 14.1%. This is because the use of RME B100 fuel requires changes in the engine design that improve the mixture formation process.
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The meaningful problem of improving crane safety, reliability, and efficiency is extensively studied in the literature and targeted via various model-based control approaches. In recent years, crane ...data-driven modeling has attracted much attention compared to physics-based models, particularly due to its potential in real-time crane control applications, specifically in model predictive control. This paper proposes grammar-guided genetic programming with sparse regression (G3P-SR) to identify the nonlinear dynamics of an underactuated crane system. G3P-SR uses grammars to bias the search space and produces a fixed number of candidate model terms, while a local search method based on an l0-regularized regression results in a sparse solution, thereby also reducing model complexity as well as reducing the probability of overfitting. Identification is performed on experimental data obtained from a laboratory-scale overhead crane. The proposed method is compared with multi-gene genetic programming (MGGP), NARX neural network, and Takagi-Sugeno fuzzy (TSF) ARX models in terms of model complexity, prediction accuracy, and sensitivity. The G3P-SR algorithm evolved a model with a maximum mean square error (MSE) of crane velocity and sway prediction of 1.1860 × 10−4 and 4.8531 × 10−4, respectively, in simulations for different testing data sets, showing better accuracy than the TSF ARX and MGGP models. Only the NARX neural network model with velocity and sway maximum MSEs of 1.4595 × 10−4 and 4.8571 × 10−4 achieves a similar accuracy or an even better one in some testing scenarios, but at the cost of increasing the total number of parameters to be estimated by over 300% and the number of output lags compared to the G3P-SR model. Moreover, the G3P-SR model is proven to be notably less sensitive, exhibiting the least deviation from the nominal trajectory for deviations in the payload mass by approximately a factor of 10.
The article presents the problems of determining the mass efficiency of a rotary feeder depending on the selection of design parameters of the device, such as outer diameter, number of blades and ...rotational speed of the rotor. The hitherto theoretical methods of calculating the feeder efficiency were presented, as well as a new method of determining the device operation parameters was proposed. For this purpose, the numerical Discrete Element Method was used, which allowed simulating the transport of limestone powder in a cell feeder with various design variants. The results of the tests showed that the above design parameters affect the instantaneous efficiency of the feeder and thus impact the distribution of the dosed material during the operation of the device. Depending on the design solution, the simulation results gave information on the fill factor of the feeders. The study showed a significant potential of DEM simulation in the design of circular feeders intended for dosing bulk materials.
The paper discusses the designing process of screw conveyors, with regard to the determination of the exploitation parameters of such devices with the use of the Discrete Element
Method (DEM). The ...influence of the chosen model input parameters on the results of the
simulations was examined. The key parameters which determine the exploitation characteristics of a screw conveyor were identified as follows: the size of a DEM particle, coefficients
of internal and external friction. Experimental measurements of the laboratory screw conveyor provided the actual exploitation characteristics of a device used for the transportation
of a limestone powder. The comparison of the results of the simulations and experiments
gave satisfactory results. For this reason, DEM simulations were identified as an effective
tool for determining and optimization of the construction and exploitation parameters of the
screw conveyors
Identification of an accurate and simple model of a complex underactuated crane dynamics for varying operational conditions is a crucial step towards designing and implementation of real-time ...monitoring and control systems to enhance crane safety and operational efficiency. This paper considers a non-parametric data-driven identification of an overhead crane dynamics using symbolic regression techniques to find compromise between model complexity and predicted output accuracy. A grammar-guided genetic programming (G3P) combined with l0 sparse regression is applied with two different variants of grammar to automatically construct a nonlinear autoregressive exogenous (NARX) model of different forms, termed extended and polynomial models. The proposed method is compared with a linear parameter-varying ARX (LPV-ARX) model. Identification is performed on experimental data obtained from a laboratory-scale overhead crane. The identified models are compared in terms of prediction accuracy, model’s complexity measured using number of model terms, and execution time. The regularized G3P method outperformed the LPV-ARX model in terms of model predictive output accuracy. The G3P with the extended grammar resulted in more accurate crane velocity prediction models than the models with the polynomial grammar. The payload sway prediction model with the polynomial grammar was less complex in all measured metrics while there was no statistical significance in the accuracy when compared to the models with extended grammar.
Analytical methods for calculations of the transport machinery are often insufficient especially when untypical granular materials are considered. Discrete Element Method (DEM) is a very useful ...numerical tool supporting designing and optimization of the
transport equipment. However, to obtain reliable DEM simulation results an accurate set of input parameters values is needed.
The most common calibration approach is to make use of a procedure where laboratory tests are performed and then the same
experiments are numerically replicated in DEM. The article presents calibration of the DEM input parameters on the example of
perlite D18-DN Based on the performed calibration, the model of perlite transport in a screw conveyor has been shown.
The article presents the results of research aimed at developing the construction of an ESP (electrostatic precipitator), as well
as the performance and selection of operating parameters of the ESP ...for household applications. The object of the experiment
was the ESP prototype, designed and made by the authors, assigned to be placed in a gas pass of a detached house. A simulation
of dustiness caused by burning solid fuels has been done. The experiment has been carried out for two different degrees of dust
concentration at the ESP inlet, by controlling the given voltage. The results proved that the proposed constructional solution of the
ESP significantly limits low emission PM2.5 and PM10 dust emitted during the process of burning solid fuels: coal and/or biomass
in boilers and fireplaces used in households or in small local boiler houses.
The Jerusalem artichoke (Helianthus tuberosus) is a high-yield crop, and a great source of fermentable sugars, which gives the plant the potential to be used as raw material for economical fuel ...alcohol production. In this article, the authors focus on the technological aspect of the biofuel manufacturing process and its properties. First, the fuel alcohol manufacturing process is described, afterwards assessing its characteristics such as kinematic viscosity, density and octane number. The amount of fuel alcohol obtained from 10 kg of biomass equals to 0.85 L. Afterwards, the mixtures of gasoline and obtained fuel alcohol are prepared and studied. Optimal alcohol and gasoline mixtures are determined to obtain biofuels with octane ratings of 92, 95 and 98. The kinematic viscosity of obtained mixtures does not differ significantly from its values for pure gasoline. The obtained biofuel mixture with 25% alcohol content yielded a decrease of sulfur content by 38%, an increase of vaporized fuel amount by 17.5% at 70 °C and by 10.5% at a temperature of 100 °C, which improves engine startup time and ensures its stable operation in comparison to pure gasoline. The alcohol obtained can be successfully used as a high-octane additive for gasolines.
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