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Automated production and assembly lines can be considered a crucial factor in accelerating the production processes and achieving the maximum financial savings. In particular, specialized single-purpose machines can significantly reduce production or assembly time. The submitted article presents a design of a single-purpose device that is used for the automated assembly of a roller bush with a screw. These components are then used for construction and agricultural vehicles to attach other components. Naturally, the design of this specific device is more demanding in terms of time consumption, precision, detail and initial investment than similar less complicated all-purpose devices. Nevertheless, single-purpose devices turn out to be a better option in the sense of quality and profit both in the long-term and high-capacity projects, such as automotive industry, agricultural and construction machinery. The best alternative was selected from several proposals using the evaluation method. The assembly machine was designed and optimized using Computer Aided Design systems and Finite Element Method analyses. The resulting equipment was used in practice, where it significantly increased the productivity and production efficiency.

This article presents a study of the amount of harmonic gear system backlash. The study shows a method for an effective measuring of the amount of backlash in harmonic gear systems. Given that this calculation tasks demand a lot of iterative operations, this article introduces a new method for creating 2D and 3D models of a harmonic gear system. At the same time, this study presents a new way of generating the geometry of a wave generator with a parametrically modified geometry. Introduction of the parametric model of a wave generator allows a rapid optimization of construction parameters, thus securing correct dimensioning and evaluation of the amount of backlash. When creating the computational model, operational characteristics were taken into consideration, therefore, the 2D and 3D computational models were created to correspond with real operation conditions to the greatest extent possible. The results of the analysis imply that the suggested method of examining the design parameters of the wave generator due to the harmonic gear system backlash is effective and correct. The benefit of this article is mainly to introduce a new dynamic computational model of a harmonic gear system and to optimize the construction parameters of the wave generator in line with the amount of backlash, which is manifested in the higher accuracy of the harmonic gear system. In the conclusion of this article we state our recommendations and acquired knowledge.

The main goal of the article is to describe the development and production of a prototype of an additional system for wheel motor bearing protection using additive technologies. These technologies include rapid prototyping and vacuum casting. These technologies greatly facilitate and speed up the whole process of developing a new component. Before the development itself, it was necessary to digitize the wheel hub using reverse engineering technology. Using a 3D scanner, a part model was created, based on which an additional system for wheel bearing protection was designed for the CAD system. The dimensional analysis of the produced prototypes was performed. Prototypes of the protection system made of different materials will be tested in common operation conditions.

Nowadays detection of deterioration of electrical motors is an important topic of research. Vibration signals often carry diagnostic information of a motor. The authors proposed a setup for the analysis of vibration signals of three-phase induction motors. In this paper rotor fault diagnostic techniques of a three-phase induction motor (TPIM) were presented. The presented techniques used vibration signals and signal processing methods. The authors analyzed the recognition rate of vibration signal readings for 3 states of the TPIM: healthy TPIM, TPIM with 1 broken bar, and TPIM with 2 broken bars. In this paper the authors described a method of the feature extraction of vibration signals Method of Selection of Amplitudes of Frequencies – MSAF-12. Feature vectors were obtained using FFT, MSAF-12, and mean of vector sum. Three methods of classification were used: Nearest Neighbor (NN), Linear Discriminant Analysis (LDA), and Linear Support Vector Machine (LSVM). The obtained results of analyzed classifiers were in the range of 97.61 % – 100 %.

This article presents the correct adjustment of the mower’s blade movement relative to the forward movement of the mower. Everywhere around us are gardens, parks and meadow, which gives us reason to solve issues with mowing. The first part of this article shows agricultural machines, which are used today and the principle of correct cut of grass stalks. The next part shows the method of adjusting the mower’s blade speed. Design of a simple model was done with the use of Solid Edge Premium CAD. For computation, MSC Adams was used and post-processing was done with the use of Matlab. The connection between MSC Adams and Matlab was created by co-simulation.

Diabetic retinopathy (DR) is a diabetes disorder that disturbs human vision. It starts due to the damage in the light-sensitive tissues of blood vessels at the retina. In the beginning, DR may show no symptoms or only slight vision issues, but in the long run, it could be a permanent source of impaired vision, simply known as blindness in the advanced as well as in developing nations. This could be prevented if DR is identified early enough, but it can be challenging as we know the disease frequently shows rare signs until it is too late to deliver an effective cure. In our work, we recommend a framework for severity grading and early DR detection through hybrid deep learning Inception-ResNet architecture with smart data preprocessing. Our proposed method is composed of three steps. Firstly, the retinal images are preprocessed with the help of augmentation and intensity normalization. Secondly, the preprocessed images are given to the hybrid Inception-ResNet architecture to extract the vector image features for the categorization of different stages. Lastly, to identify DR and decide its stage (e.g., mild DR, moderate DR, severe DR, or proliferative DR), a classification step is used. The studies and trials have to reveal suitable outcomes when equated with some other previously deployed approaches. However, there are specific constraints in our study that are also discussed and we suggest methods to enhance further research in this field.

[EN] Electric motors use about 68% of total generated electricity. Fault diagnosis of electrical motors is an important task, because it allows saving a large amount of money and time. An analysis of acoustic signals is a promising tool to improve the accuracy of fault diagnosis. It is essential to analyze acoustic signals to assess the state of the motor. In this paper, three electric impact drills (EID) were analyzed using acoustic signals: healthy EID, EID with damaged rear bearing, EID with damaged front bearing. Three angle grinders (AG) were analyzed: healthy AG, AG with 1 blocked air inlet, AG with 2 blocked air inlets. The authors proposed a method for feature extraction: SMOFS-NFC (Shortened Method of Frequencies Selection Nearest Frequency Components). Acoustic features vectors were classified by the nearest neighbor classifier and Naive Bayes classifier. The classification accuracy were in the range of 89.33¿97.33% for three electric impact drills. The classification accuracy were in the range of 90.66¿100% for three angle grinders. The presented method is very useful for diagnosis of bearings, ventilation faults and other mechanical faults of power tools. It can be also useful for diagnosis of similar power tools., This work was supported in part by Generalitat Valenciana, Conselleria de Innovacion, Universidades, ' Ciencia y Sociedad Digital, (project AICO/019/224).

This article deals with the kinematic analysis of trapezoidal suspension. Specifically, it focuses on the behaviour of the chassis when obstacle crossing was monitored. Our team is developing an autonomous mountain vehicle that will be equipped with different working adapters such as a cutter bar and a picker. The device was designed for work on slopes, hence, must be able to overcome certain natural obstacles. This implies the need to analyse the wheel suspension kinematics. The vehicle was built on a trapezoidal suspension, which has proven to be the most suitable option with respect to operating conditions. From the results obtained, it was possible to analyse the driving characteristics of the obstacle, track the rollover limits and overall safety of operation.

The article is focused on braking simulation of automated guided vehicle (AGV). The brake system is used with a disc brake and with hydraulic control. In the first step, the formula necessary for braking force at the start of braking is derived. The stopping distance is 1.5 meters. Subsequently, a mathematical model of braking is created into which the formula of the necessary braking force is applied. The mathematical model represents a motion equation that is solved in the software Matlab by an approximation method. Next a simulation is created using Matlab software and the data of simulation are displayed in the graph. The transport speed of the vehicle is 1 〖m.s〗^(-1) and the weight of the vehicle is 6000 kg including load. The aim of this article is to determine the braking time of the device depending from the input data entered, which represent the initial conditions of the braking process.

The Internet of Things (IoT) is an emerging technology in underwater communication because of its potential to monitor underwater activities. IoT devices enable a variety of applications such as submarine and navy defense systems, pre-disaster prevention, and gas/oil exploration in deep and shallow water. The IoT devices have limited power due to their size. Many routing protocols have been proposed in applications, as mentioned above, in different aspects, but timely action and energy make these a challenging task for marine research. Therefore, this research presents a routing technique with three sub-sections, Tri-Angular Nearest Vector-Based Energy Efficient Routing (TANVEER): Layer-Based Adjustment (LBA-TANVEER), Data Packet Delivery (DPD-TANVEER), and Binary Inter Nodes (BIN-TANVEER). In TANVEER, the path is selected between the source node and sonobuoys by computing the angle three times with horizontal, vertical, and diagonal directions by using the nearest vector-based approach to avoid the empty nodes/region. In order to deploy the nodes, the LBA-TANVEER is used. Furthermore, for successful data delivery, the DPD-TANVEER is responsible for bypassing any empty nodes/region occurrence. BIN-TANVEER works with new watchman nodes that play an essential role in the path/data shifting mechanism. Moreover, achievable empty regions are also calculated by linear programming to minimize energy consumption and throughput maximization. Different evaluation parameters perform extensive simulation, and the coverage area of the proposed scheme is also presented. The simulated results show that the proposed technique outperforms the compared baseline scheme layer-by-layer angle-based flooding (L2-ABF) in terms of energy, throughput, Packet Delivery Ratio (PDR) and a fraction of empty regions.

This article presents a model of the geometry of teeth profiles based on the path of contact definition. The basic principles of the involute and convex&ndash, concave teeth profile generation are described. Due to the more difficult manufacturing of the convex&ndash, concave gear profile in comparison to the involute one, an application example was defined that suppressed this disadvantage, namely a planetary gearbox with plastic-injection-molded gears commonly used in vehicle back-view mirror positioners. The contact pressures and the slide ratios of the sun, planet, and ring gears with both teeth profile variants were observed and the differences between the calculated parameters are discussed.

This article is focused to design of vacuum chamber for deep drawing machine working by high temperatures. The high temperatures are demanding because of use of molybdenum sheet, which should be drawn by temperatures approx. 300 °C. The thermal analysis is important for the correct design of the deep drawing machine for two reasons: The first is the correct temperature of the molded material—molybdenum sheet and the second is the temperature around the seals of vacuum chamber. The simulation forms the basis for selecting the appropriate type of seals. The result of the simulation is a thermal field of working components: the punch, the die, the blank holder, the working plate, and the working table. The second important analysis result is the temperatures of components, which are in contact with seals in particular places.

This article presents a brief overview of weighing systems and devices designed to facilitate fluent and safe road traffic. The number of vehicles on roads is perpetually on the rise, resulting in increased wear of road surfaces. This is why weight check gates have widely been implemented to check the speed and weight of a vehicle against what is permitted by law. A cheaper, albeit more time-consuming, traffic weighing alternative would involve weighing points using weighbridges or mobile axle scales. The second part of this article examines the development of an axle scale. The design and calculation works were performed with the use of the Creo Parametric CAD system and the ANSYS Workbench FEM system.

The maritime transport is particularly exposed to danger due to the environment of its operations. These are the threat dependent and independent of human e.g. environmental, safety health and life of humans or belongings. In spite of attempts to limit the risk of danger, it is impossible to completely eliminate it. The article presents some aspects of the state of transportation safety in the Baltic Sea from Statistical Yearbook of Maritime Economy and Helcom as well as attempt the undertaken to analyses the security state of this sea area in 2009 to 2015.

Large demand for bulk of sapphire optical products, which are widely used as illuminators, optical windows in aviation and aeronautics etc., generates the inquiry of effective production of high quality industrial crystals. The technology of crystal growth with the horizontal single crystal sapphire crystallization method is based on putting the crystal seed into the front of the crucible resistant to temperatures up to 2150°C. Without encompassment of the production technology of this special container made from thin molybdenum sheet is not realistic to consider the productive exploitation of horizontal crystallization systems in engineering practice. This paper presents the analysis of the possibility of the molybdenum sheet local resistance heating by its deep drawing to obtain better drawing properties by increased blank temperature.

This article is about a vehicle model which is created in software Matlab Simscape Driveline. In this model the motor is created like a subsystem by Simulink blocks and input data were measured by single roller dynamometer for cars (SRD). Measured data are the input into the model by Lookup Table block. The vehicle model is made by gear, differential, tire and vehicle body blocks. We studied the forces on tires, the vehicle velocity and the slip.

The subject of this article is an introduction of the concept of a device for deep drawing in extreme conditions. In this case, extreme conditions represents drawing process in vacuum by high temperatures required by molybdenum sheets forming. The first part of the paper is about the functional, structural, economical, technological, operational, safety, environmental, legal and design requirements. The second part of the article deals with description of possible variants of the mechanism structure. The paper describes also the results of the research work by evaluating the variants. The variants scores were rated by parameters, which are essential for properly work of the mechatronic system.

The article describes modeling and simulation of the vehicle physical model. The vehicle model is simplified and it is made up of body and 4 tires. The model contains elementary information of the vehicle geometry - dimensions and center of gravity position. These information about the vehicle are sufficient for mathematical description of vehicle. The model is made of basic elements like engine, gearbox, differential and tires, which are represented by blocks. The model includes also other blocks, which are used to show measured outputs and control blocks, that make the vehicle mechatronic systems controllable according the driver model inputs. There are also studied the forces on tires and the engine speed of the vehicle model.

Natural disasters not only disturb the human ecological system but also destroy the properties and critical infrastructures of human societies and even lead to permanent change in the ecosystem. Disaster can be caused by naturally occurring events such as earthquakes, cyclones, floods, and wildfires. Many deep learning techniques have been applied by various researchers to detect and classify natural disasters to overcome losses in ecosystems, but detection of natural disasters still faces issues due to the complex and imbalanced structures of images. To tackle this problem, we propose a multilayered deep convolutional neural network. The proposed model works in two blocks: Block-I convolutional neural network (B-I CNN), for detection and occurrence of disasters, and Block-II convolutional neural network (B-II CNN), for classification of natural disaster intensity types with different filters and parameters. The model is tested on 4428 natural images and performance is calculated and expressed as different statistical values: sensitivity (SE), 97.54%, specificity (SP), 98.22%, accuracy rate (AR), 99.92%, precision (PRE), 97.79%, and F1-score (F1), 97.97%. The overall accuracy for the whole model is 99.92%, which is competitive and comparable with state-of-the-art algorithms.