The effects of high-pressure abrasive water jet (AWJ) machining strongly depend on the dimensions and distribution of the abrasive grains. This study explores how abrasives break down during the generation of AWJ operations. Following formation in the cutting head, the abrasive material's grain size was measured, and the Folk and Ward technique was used to assess grain distribution. Grain distribution w (…)
This article addresses the problem of constructing an accurate and reliable navigation system for autonomous mobile robots (MR) operating in environments where Global Navigation Satellite System (GNSS) signals are unavailable. A hybrid approach is proposed, combining data from odometry, an electronic compass, and an active ultrasonic beacon system. Based on the technical specification for the developmen (…)
The increasing penetration of photovoltaic systems in modern power grids creates stability challenges caused by the low inertia of inverter-based generation. This leads to higher frequency deviations and reduced robustness during dynamic operating conditions. This paper proposes an enhanced adaptive Virtual Synchronous Generator control strategy combined with Particle Swarm Optimization for optimal tuni (…)
This paper addresses the problem of community detection (clustering) in self-organizing systems consisting of a large number of similar interacting elements. A three-dimensional neural network is chosen as a model example, where neurons act as elements and synaptic connections serve as edges of a weighted graph. An adaptation of the Louvain method, one of the most efficient algorithms for community dete (…)
A nondestructive optical method for determining the complex dielectric permittivity ε(ω) of silicon photovoltaic converters (PVC) surfaces modified with silver nanoparticles is developed and experimentally validated. The method is based on backscattered radiation analysis and enables reconstruction of both real and imaginary components without altering the structure of objects under study [Kuric 2022]. (…)
The article presents an experimental methodology for evaluating fluid muscle stiffness using a controlled linear drive and a measuring chain based on a strain gauge force sensor. The measuring assembly consists of a strain gauge sensor, a signal converter, a programmable logic controller, and an electric actuator ensuring precise positioning. The measurements were performed at a vacuum level of 95% and (…)
The work establishes a number of features regarding the mechanics of freezing wet quartz sands when manufacturing products of limited sizes from them. Products of limited sizes from frozen sand in foundry production are casting models used for manufacturing volumetrically closed and detachable casting molds using the SMS-process method, frozen casting molds and rods, etc. The work used quarry quartz san (…)
Among the known standardized bronze grades, there are currently no foundry structural bronzes that would simultaneously combine both non-magnetism and corrosion resistance, in particular, in tap water and seawater. The presence of bronze with such a list of preferential properties will allow not only to expand the boundaries of bronzes as a structural material using, but also to provide prospects for in (…)
Abstract: This paper deals with the kinematic analysis of multi-member mechanisms and robotic manipulators using MSC ADAMS simulation software. Attention is focused primarily on the analysis of trajectories, positions, velocities and accelerations of selected points of mechanisms, as well as the determination of the working space of manipulators. Analytical relationships and numerical calculations perfo (…)
This paper addresses the design and thermal–hydraulic analysis of a heat exchanger designed for cooling sampled process air from a fermenter prior to its transport to a mass spectrometric analyzer. Due to the high humidity of the sampled air, effective cooling is required to prevent unwanted condensation during transport over a distance of 200 m. A tube-in-tube counter-current heat exchanger was select (…)
The aim of the research is to assess the energy efficiency of proposed heat, electricity and hot water supply systems for apartment buildings. Schematic solutions of heat and power generating units based on liquid-vapor jet devices. The proposed schemes are improved solutions for mini-TPP and heat pump unit, and fundamentally new decisions have been developed, the so-called combined scheme of heat-&-ele (…)
Optimization methods play a key role in the design and control of modern powertrains in the current automotive industry. Emphasis is placed primarily on the implementation of optimization algorithms and predictive models that are used by engine control units. These are intended to ensure effective control of torque, fuel consumption and vehicle dynamics in real time depending on driving conditions and d (…)
Currently, emphasis is placed on the quality of production in connection with its efficiency. The emphasis is mainly on machining processes in which the material removal rate is low. These machining processes include wire electrical discharge machining (WEDM). This is a technology that allows material removal using cyclically repeated electrical discharges. It is characterized by high production quality (…)
This paper investigates the relationship between the physical properties of a controlled dynamic system and the optimal configuration of hyperparameters in the multi-objective evolutionary algorithm NSGA-II (Non-dominated Sorting Genetic Algorithm II). The aim is to determine whether, and to what extent, the optimal hyperparameter settings of NSGA-II change in response to physical modifications of the s (…)
Computational Fluid Dynamics (CFD) simulations are a valuable tool for hydrodynamic pump flow analyses. Recently, emphasis has been placed on the analyses of all pump modes such as turbine mode, pump mode, dissipative modes etc. Some regimes are very difficult to simulate numerically, especially transition states. These regimes must be analysed using multiple modelling approaches, considering differen (…)
This paper presents a method for robust tracking of multiple pendulums using video analysis under imperfect lighting conditions. The experimental setup consists of five pendulums recorded by a stationary camera at 30 frames per second. Object detection is performed using color-based segmentation in the HSV color space implemented in Python with the OpenCV library. Two approaches are compared: a baseline (…)
In milling, one of the main concerns is the tendency of introducing high magnitude tensile residual stresses in the machined surface, very harmful against fatigue. To assure a high surface integrity without postprocessing operations, a new approach is proposed: milling under an externally applied bending load. This article presents a simple fixture design to efficiently achieve this objective, and the e (…)
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