Search

A Brain–Computer Interface (BCI) processes and converts brain signals to provide commands to output devices to carry out certain tasks. The main purpose of BCIs is to replace or restore the missing or damaged functions of disabled people, including in neuromuscular disorders like Amyotrophic Lateral Sclerosis (ALS), cerebral palsy, stroke, or spinal cord injury. Hence, a BCI does not use neuromuscular output pathways; it bypasses traditional neuromuscular pathways by directly interpreting brain signals to command devices. Scientists have used several techniques like electroencephalography (EEG) and intracortical and electrocorticographic (ECoG) techniques to collect brain signals that are used to control robotic arms, prosthetics, wheelchairs, and several other devices. A non-invasive method of EEG is used for collecting and monitoring the signals of the brain. Implementing EEG-based BCI technology in home automation systems may facilitate a wide range of tasks for people with disabilities. It is important to assist and empower individuals with paralysis to engage with existing home automation systems and gadgets in this particular situation. This paper proposes a home security system to control a door and a light using an EEG-based BCI. The system prototype consists of the EMOTIV Insight™ headset, Raspberry Pi 4, a servo motor to open/close the door, and an LED. The system can be very helpful for disabled people, including arm amputees who cannot close or open doors or use a remote control to turn on or turn off lights. The system includes an application made in Flutter to receive notifications on a smartphone related to the status of the door and the LEDs. The disabled person can control the door as well as the LED using his/her brain signals detected by the EMOTIV Insight™ headset.

The purpose of prosthetic devices is to reproduce the angular-torque profile of a healthy human during locomotion. A lightweight and energy-efficient joint is capable of decreasing the peak actuator power and/or power consumption per gait cycle, while adequately meeting profile-matching constraints. The aim of this study was to highlight the dynamic characteristics of a bionic leg with electric actuators with rotational movement. Three-dimensional (3D)-printing technology was used to create the leg, and servomotors were used for the joints. A stepper motor was used for horizontal movement. For better numerical simulation of the printed model, three mechanical tests were carried out (tension, compression, and bending), based on which the main mechanical characteristics necessary for the numerical simulation were obtained. For the experimental model made, the dynamic stresses could be determined, which highlights the fact that, under the conditions given for the experimental model, the prosthesis resists.

This paper describes the transition towards a composite structure, with the same overall aerodynamic characteristics, for a tail rotor blade of an IAR330 helicopter. The newly proposed structure of the composite blade is made of a carbon-roving spar embedded with epoxy resin, a hexagonal-cell honeycomb core manufactured by fused deposition modelling, and an outer skin made of multiple carbon-fibre-reinforced laminae. The blade was manufactured by the authors using the hand lay-up method at a scale of 1:3 with respect to the real one, and all stages of the manufacturing process are extensively described in the paper. The experimental tests were performed on an Instron 8872 testing machine by applying a bending force on its free edge, similar to the testing methodology employed by various composite blade manufacturers. A three-dimensional numerical model of the tail rotor blade was conceived, analysed using the finite element method, and validated by comparing the numerical and experimental values of the maximum bending force. Further, the model was used for a complex finite element analysis that showed the very good behaviour of the proposed composite blade during flight and emphasized the main advantages brought by the proposed composite structure.

In realizing a high-performance composite material, it is important to take into consideration all the factors that influence the structural response of the component when exposed to service conditions. Thus, in the case of the laminar skin of a composite tail rotor blade, the study of the stress distribution on each lamina is important, so that the optimal design can be chosen. The ACP Post module of the Ansys Workbench finite element software offers the possibility of visualizing the stress distribution on each lamina of the skin, as well as the value of the safety factor for multiple failure criteria.

The main objective of the paper is dimensioning of the impact energy absorption elements and verification of their mechanical strength in the case of a rail transport vehicle. The calculation consisted in optimal setting of the inside diameter, wall thickness and cylinder height. In the calculations, the standard for cold drawn pipes EN 10216: 2002 has been taken into account so that the chosen dimensions correspond to those delivered by the industrial suppliers. Based on the calculations presented in the paper, a numerical model will be developed, analyzed using the finite element method and validated experimentally.

This paper presents the Fuzzy Logic method in order to evaluate the performance of a real flow-line. The flow-line comprises a number of machines that are arranged in series and the flow of products is continuous. The objective of this paper consists in the production rate prediction of a manufacturing system using the Fuzzy Logic method through ANFIS SUGENO and FIS MAMDANI. Input data are processed in ANFIS SUGENO to view the construction mode of the input membership functions in order to achieve our own model of FIS MAMDANI. Input variables' membership functions are modified by removing the values which exceed the representation range, after which the inference rules and the representation range of the output variables are to be established. The forms of membership functions are very important because they influence the prediction accuracy. A case study is carried out to demonstrate the performance and flexibility of the proposed approaches.

This paper deals with the use of three alternative methods in order to modelling, simulation and estimation of the production rate. The methods for evaluating the analytical performances are based on stochastic modelling of the production systems flows. Processes that imply random phenomena have traditionally been modelled through the use of statistical distributions. The paper shows that the Fuzzy Logic methods are able to achieve similar solutions to conventional methods. The objective of this work is to implement the main contributions brought in the industrial engineering field by modelling, simulating and estimation of the production rate, in a real case-study.

Petroleum drilling rigs are used for identifying geologic reservoirs and for creating wells for extraction. The mud pumps of drilling rigs are operated at high mud rates to make possible the drilling process. The durability of the mud pump valves to erosive wear, due to the action of abrasive drilling fluid containing solid particles, depends on their constructive form and on the mud flow velocity. This paper analyzes a few methods of increasing the wear resistance of mud pump valves.

The housings of satellite's electronic units have been traditionally made of aluminum. However, as it has been shown in other aerospace applications, the use of composite materials could potentially lead to large mass savings. With the high costs of sending a unit mass of payload into orbit, the mass should be minimized. Composite materials may be able to meet the multiple performance requirements set for the housings, and also carbon fiber-reinforced plastics (CFRP) due to their higher specific stiffness and strength can obtain an important mass saving over aluminum. The main objective of the study is the design and finite element analysis of a composite housing for electronics in a satellite that meets the structural requirements of an existing equipment unit made by aluminum.

In order to compensate the centrifugal force that appears in railway vehicles during running in curves, overwidening of the track and superelevation of the external rail are executed. In this paper, we analyze the influence of the cruising speed on the stress state in the frames of the bogie, in a turn with a radius of 500 m of an Eacs car, equipped with Y25 Cs bogies.

The main aim of this article is to present a fatigue cycle counting program for a given application. The application is an example from a given case presented in the literature, with the analytical solution discussed herein. Cycle counting for irregular fatigue spectra is important to evaluate for various given load cases, in different industries. Such evaluations are difficult to make without dedicated computer programs. Several specific methods are available in the technical literature to evaluate irregular fatigue spectrums. For this study, one of the most well-known and used methods was chosen, the rainflow-counting algorithm. This method extracts the number of cycles from an irregular fatigue recording which, in turn, is used in the Palmgren-Miner rule to evaluate the fatigue damage for the examined application, considering that the Wohler curve is given. The developed program is written in the Python programming language. The theoretical background is presented for the application and the use of it with the program algorithm.

The primary objective of this study was to investigate the compressive behavior of 3D-printed specimens made of a thermoplastic polyurethane filament, specifically colorFabb varioShore TPU, which incorporates a foaming agent. The foaming technology makes it possible to manipulate 3D prints' properties by adjusting process parameters that affect the level of expansion, such as printing temperature, printing speed or flow ratio. This capability opens new possibilities for 3D-printed personalized foot orthotics or for static comfort-oriented applications by tailoring the stiffness of the print based on the application requirements. Since infill density and infill pattern also affect the compressive characteristics of 3D prints, this research took these two parameters into account as independent variables, alongside the printing temperature. Thus, the specimens with printing temperatures set at 190 °C, 220 °C, and 240 °C, gyroid and honeycomb patterns, and infill variations from 10 % to 35 % in 5 % increments were experimentally investigated in compression testing. The evaluation was conducted to determine the influence of these factors on the stiffness of prints at 10 % and 20 % strains, in accordance with established standard. The findings had an important practical value as they provide data for adjusting the variable stiffness based on peak plantar pressure measurement data when developing tailored foot orthoses (insoles), which was the second objective of the research. The most influential factor affecting the compressive strength was the printing temperature, followed by infill density and pattern type. The difference in compression modulus between 10 % and 20 % strains did not exhibit statistical significance. Moreover, the main effects plots indicated minimal variations in compression modulus effects at 220 °C and 240 °C, whereas an important difference was observed at 190 °C printing temperature, which was confirmed by scanning electron microscopy investigations showing foamed layers at 220 °C and unfoamed layers at 190 °C. Furthermore, interaction plots revealed no significant interaction effect among the studied variables. Additionally, a comparison of samples’ sizes and densities before and two months after testing indicated no observable modifications When applied to custom orthotics (five pairs of insoles were customized and tested), the experimental findings documented variations in the reduction and distribution of peak plantar pressure based on the infill variability.

The main objective of this paper is to describe the creation and use of a fatigue analysis program written in VBA, designed for the preliminary sizing of metallic structural components used in aerospace applications, subjected to one or multiple fatigue loading cases. The VBA programing language was chosen because of its direct control over the most common spreadsheet computational program, Microsoft Excel. Metal fatigue analysis is an important type of analyses for modern structures. Fatigue failure accounts for around 80-90 percent of common structural failures, and therefore, a quick and reliable analysis is necessary so as to evaluate the structure’s bearing capacity to fatigue load. Due to the nature of the fatigue load and the importance of the structural component, such an analysis can be very time consuming, starting from the finite element model preparation and going through the actual analysis; thus, there is a need for a tool that can evaluate the stress data from

The purpose of these article is the evaluation of the influence of the components of a multilayered honeycomb composite material, about the load caring capacity, when the material is subjected to a complex static loading , in the linear elastic domain. The numerical simulation approach was used for these study, and the results were validated experimentally.

The goal of this article is to study the behavior of sandwich structures with honeycomb core during and after an impact. In this purpose, a test program was created and afterwards was applied. It consists in the application of multiple impact energies over the multi-layered structure. Impacted specimens are subjected to a compression test in order to determine the load capacity after impact. The results are summarized at the end of the paper in a graph that shows the loading capacity of multi-layer structure depending on the impact energy.