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Many researchers are interested in using natural fibres to treat due to recent advancements in polymer characteristics. The mechanical properties of three types of bars are studied in this paper: Cotton Fibre-Reinforced Polymer bars, Cotton/Carbon Fibre-Reinforced Polymer bars, and Cotton/Glass Fibre-Reinforced Polymer bars. The goal of the paper was to create low-cost bars with comparable mechanical performance and corrosion resistance to steel reinforcement. The bars were made using two methods: fibres immersed in polymer and fibres coated with polymer by repeated tension and relaxation of fibres. The second method produced better results in terms of the tensile strength of Cot.CFRP, Cot.GFRP, and Cot.FRP bars, which were 688, 477, and 284 MPa, respectively, and the stress–strain curve revealed brittle behaviour for all bars and modulus of elasticity of 43, 31 and 22 GPa. When sand was put on the bar's surface, the bars demonstrated a good connection with the concrete. It also showed good resistance to moisture, alkaline solutions and acids, as well as heat resistance at temperatures below 200°C. [ABSTRACT FROM AUTHOR]

The high specific stiffness materials are used to design the space payload components. These components should sustain the extreme environmental condition throughout their life cycle without failure. The prerequisites of future space missions need lightweight materials which must be mechanically strong and high thermal and electrically conductive. The Carbon Nanotubes (CNTs) are efficient filler material in composite or metal matrix to enhance greater electrical and thermal conductivity. The quality of the CNT nano composite relies upon several parameters like the types of CNTs, its purity, aspect ratio, amount of loading, alignment, and interfacial adhesion between the nanotube and polymer. The performance of the CNT-CFRP composite depends on the successful execution of the processing technique. This review paper intends to highlight the enhancement of the mechanical, thermal, electrical properties of the composite, and the challenges to achieving it. This review paper helps to optimise the process parameters to fabricate Space Payload Components, required to replace existing high-density Space Qualified Materials. This review paper should help optimize the process parameters to fabricate Space Payload Components, which can be excellent alternatives to the existing high-density Space Qualified Materials without making any compromise on the performance index. [ABSTRACT FROM AUTHOR]

This paper presents a thermal error model for a lathe CNC machine using temperature on moving parts, which is usually a difficult measurement. Different working conditions are performed to obtain temperature and thermal displacement of the machine. A multi-linear regression model is applied for modelling relationship between temperatures and thermal errors. Data of two constant working conditions are implemented to find out the fitting function. Through analysis, it shows that thermal errors for X- and Z-axes can be estimated based on only four temperature points (T2, T3, T10 and T12 for the X-axis and T4, T6, T7 and T11 for the Z-axis). Results reveal that using movable part temperature data (T12), the average and maximum error in the predicted thermal displacement of the X-axis can be reduced about 1/3 and 2/5 compared to without using T12, while the movable temperature point on Z-Screw (T8) has a tiny effect on the average and maximum error of predicted thermal displacement of the Z-axis. Results herein can provide useful information to develop a thermal compensation for the CNC lathe machine. [ABSTRACT FROM AUTHOR]

This paper presents an analysis of stress developed in flex-gear (FG) cup with conventional strain wave generating (SWG) cam and split-cam SWG in strain wave gear/harmonic drive (HD), using initial load distribution by tooth pairs as a boundary condition in finite element method (FEM). The initial load distribution by tooth pairs is achieved with the assembly of ring gear (RG) and deformed FG before the application of any external load. A closed-form solution to the analytical method describes the exact initial load distribution by tooth pairs in the presence of secondary contacts. However, with spit-cam SWG the phenomenon of secondary contact is completely eradicated. Therefore, the load is distributed by contacting tooth pairs that lie only in the line of action and the tooth pair that lies along the major axis of split-cam SWG experiences maximum load compared to conventional SWG. The strain developed in FG cup based on the load distribution with both SWG cams obtained from FEM is verified with the experiment. The comparison shows a rise of 44 microns in circumferential strain around the major axis of deformed FG, when RG is assembled. This testifies the presence of initial load, which is distributed among all interfering tooth pairs before applying external load. [ABSTRACT FROM AUTHOR]

The lifting permanent magnet is a new type of magnetic transport device consisting of a mechanical driving mechanism and a permanent magnet system. It can reduce power consumption as opposed to lifting electromagnet. However, the single-drive mechanism could not be used in the inclined condition, and how to calculate the balance working point of the magnetic circuit with several permanent magnet limits its application and development. In this paper, an anti-inclined mechanism with double drive mechanism was designed and implemented. The concentric shafts and the reversing gear were adopted to realise synchronous rotation. For the permanent magnet system, the iteration method for multi-magnets balance working point analysis is proposed and implemented. Based on the prototype experiment, the anti-inclined lifting permanent magnet hoisted a 1 ton weight workpiece successfully at an inclination angle of 30 degrees. And the measurement experiment proved that the iteration method is more precise than the conventional isolated method and is a better preparation for analysing the magnetic force and residual magnetic field strength. [ABSTRACT FROM AUTHOR]

A new generation of advanced composite materials has recently emerged through the use of Carbon Nanotubes (CNTs) as the reinforcing constituent in polymer matrix. In this paper, the dynamic response of polymer sandwich beams with functionally graded face sheets subject to two successive harmonic moving loads has been studied. Three different patterns of CNT's distributions for the face sheets have been investigated: Uniform Distribution (UD), Symmetrically Functionally Graded (SFG) distribution, and Unsymmetrically Functionally Graded (USFG) distribution. A thorough study on the effects of velocity, position, excitation frequency, and the phase angles of loads has been carried out using the Radial Point Interpolation Meshfree (RPIM) method based on the 2D theory of elasticity. The SFG is found to result in the highest stiffness of all three distribution patterns. Increasing the volume fraction of the reinforcement is seen to have resulted in an increase of around 33% in the flexural rigidity of the SFG beam. Also, decreasing the frequency is seen to have suppressed the deflection of the USFG type up to 90%. The current research presents a reliable computational framework to help provide an insight into the design of an optimum sandwich structure subject to a complicated state of loading. [ABSTRACT FROM AUTHOR]

Thermal Barrier Coatings (TBCs) have been the topic of scientific research and development in surface engineering. TBCs provide effective surface protection onto the hot components of gas turbines and aero engines, enabling them to operate at high inlet gas temperatures. This paper aims to present state-of-the-art research contributions to strengthen the understanding of growth and development in the ever-increasing field of TBCs. The paper emphasises and consolidates major research progress and contributions carried out in the literature and briefly surveyed in the two most promising research categories, viz. growth and development in deposition techniques for TBC and exploration of TBC materials. A review will help the research community to understand the existing deposition processes and their contribution to future needs. [ABSTRACT FROM AUTHOR]

Recently, solar thermal energy has been considered the main type of renewable energy used widely to provide heat energy and produce electrical power. Evacuated tube solar collectors (ETSCs) are used in various weather circumstances such as clear, cloudy, windy, hot, and cold weather, and their efficient system supplies latent heat storage fluid with higher temperature and lower heat energy loss compared to the flat-plate solar collectors (FPSCs). This review paper is considered an investigation on adding nanofluid particles to the evacuated tube solar collector-PCM, indicating future evacuated tube solar collector designs and predicting the suitable high- or low-temperature PCM for various types of applications. Also, three main types of ETSCs, heat pipe, Thermosyphon, and U-pipe, with their applications are reviewed, and the factors that influence the collector performance and efficiency are discussed. Moreover, the properties that affect the selection of the PCM and the usage of various types, sizes, and volumetric concentrations of nanofluid as a working fluid for each ETSC are investigated with their enhancements for each type. Lastly, this paper provides future ideas for using additive nanofluid materials as a working fluid to improve the performance and efficiency of ETSCs. [ABSTRACT FROM AUTHOR]

Autonomous robots are designed to support humans in diverse ways including companionship and assistance, as technology evolves, the burden of physical tasks which were performed by humans in the past are getting reduced. Autonomous guidance and navigation are popular fields that use mobile robots to replace humans. These robots are widely used in space, defence, education, and industry and require navigating safely through different environments. A significant aspect of Autonomous Robot Navigation is an obstacle and pedestrian avoidance. Most of the outdoor guiding robots follow the concept of SLAM (Simultaneous Localisation and Mapping) for moving from the initial point to the goal point. Moreover, image processing plays a vital role in the detection and recognition between humans and objects. The existing methodology comprises implementing autonomous tour guide robots are based in embedded systems which has a high degree of recognition accuracy. This paper provides a comprehensive review of the existing autonomous campus and tour guiding robots. This paper is steered at providing a satellite view of these existing assemblies and the advances made with them. [ABSTRACT FROM AUTHOR]

Friction stir processing (FSP) is used to enhancing the hardness, tensile strength, corrosion and wear resistance of the substrate by changing the microstructure and through reinforcing the surface with hard-particles. In this paper, the available literatures have been carefully scrutinised and systematically categorised into FSP process and its resulting effects on the different grades of aluminium-based metal matrix composites (AMMCs). The effect of various reinforcements on AMMCs is also discussed. The objective of this paper is to review the various FSPed AMMCs fabricate at different operating conditions under various FSP parameters and summarise their effects on the microstructure and final properties of surface composites. Improvement in mechanical properties, corrosion resistance and wear resistance were observed. Fine grains of 100 nm to 400 nm in size were obtained in AA7075-T6 matrix after multi-pass FSP with rapid cooling. In AA7075/9 wt% TiB2 SCs, the grain size reduces from 335 µm (cast AA7075) to 6.3 µm, UTS increased to ~237%, hardness increased to ~246% and wear rate reduced to ~47% as compared to cast AA7075. This review paper will be helpful to new researchers working in the field of FSP, as it comprises significant knowledge related to AMMCs through FSP. [ABSTRACT FROM AUTHOR]

This paper investigates the effectiveness of feed rate, depth of cut, and cutting speed on material removal rate (MRR) and surface roughness (SR) of CNC lathe machines on AL6061 Materials. A combined use of Taguchi, Response Surface Methodology (RSM), and Genetic Algorithms (GA) is proposed to study and optimise turning processes. Firstly, the RSM with a fractional factorial design is implemented to indicate the significance and influence of process parameters on RSM and MRR. With the achieved data, regression models are formulated to present the relationship between control factors and the responses and are proven reliable in predicting through statistical analysis and validating experiment results. Further, a multi-objective genetic algorithm (GA) was used to obtain a Pareto solution set with multiple combinations of factors for optimal MRR and SR. Then, the best trade-off between process parameters is analysed to achieve desired quality outcomes. The results indicate that the proposed approach provides an effective solution for CNC Turning machines and can extend to similar problems in various fields. [ABSTRACT FROM AUTHOR]

Large pulsation and impact occur during the working process of hydraulic rock drill, which has a negative influence on the system. Aiming at this phenomenon, the related characteristics of hydraulic fluid inertia are studied in this paper. The dynamic model of impact and reversing mechanism of rock drill is established. Through the parameter analysis of the model, the concepts of hard parameter quantity and soft parameter quantity are proposed. The influence coefficient C of the initial section of crevice flow including the influence of fluid inertia is deduced, and the comprehensive factors such as hydraulic oil velocity, unstable flow and friction resistance are analyzed, The value of soft parameter quantity ζ is (ξ+1) ~ (ξ+ 1.5)。The pressure test of the working chamber is designed and 7 groups of data are obtained. Through data analysis, the influence of C on the simulation results is obtained, which has a great influence on the reversing valve. The deviation of simulation data of left and right valve chamber pressure is increased from ± 8% to ± 3%. It has a certain impact on the impact piston. The deviation of simulation data increases from ± 5% to ± 3%, and has little impact on the accumulator. The deviation of simulation data increases from ± 4% to ± 3%. [ABSTRACT FROM AUTHOR]

This paper presents the effect of an inclined casing groove on the aerodynamic performance of a single-stage transonic axial compressor, NASA Stage 38, using three-dimensional Reynold-averaged-Navier-Stokes equations with the k-ε turbulence model. The research was carried out to examine the effects of four casing groove parameters: angle, width, depth, and location. Validation of a numerical model for a single-stage transonic axial compressor was conducted to evaluate the computational fluid dynamics method. Most of the simulations showed positive results with an increase in stall margin, adiabatic efficiency, and total pressure ratio, in which the maximum stall margin, adiabatic efficiency, and total pressure ratio can be raised by 87.09%, 0.13%, and 1.57%, respectively, as compared to the smooth casing case. [ABSTRACT FROM AUTHOR]

This paper presents a comparative performance study of cooling techniques based on air-assisted water spray and jet impingement for heated moving metallic plates. To achieve the heat transfer characteristics of spray and jet cooling methods, an experimental setup was developed to accommodate the spray (SIC) and jet impingement cooling (JIC). The temperature at different locations of the plate was taken by K-type thermocouples embedded therein and attached to CHINO-make data acquisition system. The cooling curves obtained were utilised for computing the cooling rates. Experiments were conducted by varying the parameters, e.g. pressure of air and water, distance between plate and nozzle tip and speed of plate as per Taguchi design of experiments. The results revealed that SIC has great advantage over the JIC method under the same thermal conditions. There was a fall of cooling rate with increase in plate thickness for both SIC and JIC. The requirement of shorter length of run-out table (ROT) in case of SIC has established the cost effectiveness of using SIC compared to JIC. The cooling process played a critical role in steel manufacturing industry where the determined cooling rates evaluated the setup costs during planning phase of the project. [ABSTRACT FROM AUTHOR]

Since last few decades, a lot of work has been done on the evolutionary techniques to solve the optimisation problems. With the time passes, these techniques were modified, and also new algorithms were introduced to improve the performance. These techniques had been used by many researchers in synthesis of mechanisms to get the optimum results with minimum design errors. Improved harmony search (IHS) algorithm is developed from harmony search technique by improvising the harmony in HS algorithm. This technique is inspired by searching the best state of harmony in musical process in which a jazz musician make practice after practice to find the same. In this paper, IHS algorithm is utilized to synthesize four-bar path generation mechanism. A mathematical model was derived using vector loop closure equation, wherein the error function, representing positional error between actual and desired points, was considered for forming objective function. The penalty function was used to prevent violation of structural constraints corresponding to Grashof's criteria and input crank angle sequence. Three different cases were studied with ten, fifteen and eighteen precision points with and without prescribed timings. The results obtained from the study, compared with other evolutionary techniques from literature, and found significant competition. [ABSTRACT FROM AUTHOR]

This paper presents static modelling and simulation of a spherically-shaped hyperelastic balloon actuator subjected to an angular rotation with an internally applied air pressure. These actuators are extensively used in soft robotics because its safe and flexible nature. The balloon actuator is a pneumatic-type actuator made of a polymeric material. A continuum mechanics-based analytical modelling and Finite element method-based simulation are performed to predict the response of the actuator for a given angular rotation with internally applied air pressure. The proposed modelling framework is subsequently utilised to perform the parametric studies for varying pressure, thickness, and rotational speed of the actuator. Various elastic instability curves are also obtained to examine the critical inflation of the rubber balloon actuator. The analytical findings agree well with the FEM simulations. [ABSTRACT FROM AUTHOR]

Vehicle active safety system is the hotspot of current research and development, and the road adhesion coefficient is one of the essential parameters in the development of automobile active safety system, which plays a pivotal role in automobile safety. To improve the real-time performance and accuracy of the road adhesion coefficient, this paper proposes different control methods and compares and analyzes them. To accurately estimate the road adhesion coefficient in real-time, an eight-degree-of-freedom vehicle model was adopted in this paper. According to the tire torque and wheel speed, the adhesion coefficient was estimated based on the second-order nonlinear extended state observer. The experimental data, such as slip rate, using the improved tire model, is based on the recursive least squares method with forgetting factor and fuzzy logic algorithm real-time of tire-road friction coefficient estimation. The results show that the observer can effectively observe utilisation adhesion coefficient, and both control algorithms can estimate the road adhesion coefficient in real-time, effectively and quickly. On different roads, the use of the recursive least squares algorithm resulted in higher estimation accuracy, better robustness, and better control effect than using a fuzzy logic algorithm. [ABSTRACT FROM AUTHOR]

In the third industrial revolution (IR), mechatronics engineering has emerged, which is the merger of mechanical and electronics engineering along with information technology to an extent. In the current industrial revolution (fourth), the amalgamation of mechanical with Artificial intelligence (AI) has been used to simulate human behaviour in machines. In the earlier decades, the application of AI in mechanical engineering has expedited and the increased volume of related research papers is a proof of this fact. The broad domain of mechanical engineering has a lot of potential for machine learning applications in order to detect errors, minimise rejection, improve product quality, optimise a system, and so on, as it has not been intensely explored although. This article’s goal is to give a structured evaluation of works that employ vision systems and to attract researchers to analyse its potential integration with machine learning (ML) techniques from the industry 4.0 viewpoint. Current trends and research gaps in the area of manufacturing in collaboration with ML are also discussed at appropriate places. A general procedure to carry out research in the field of mechanical engineering is also presented. The results of various studies highlighted in this paper confirm that the implementation of AI in ME has provided an optimum solution to many mechanical problems that improved product quality and minimised the associated cost. Finally, the authors have led a direction to empower researchers in order to explore various areas in mechanical engineering from Industry 4.0 and AI perspective and enable possible topics for future research. The article concludes by providing challenges that may be faced in the coming future about the use of machine learning in mechanical engineering problems. [ABSTRACT FROM AUTHOR]

In the above paper five errors have been found. [ABSTRACT FROM AUTHOR]

The present paper proposes a method for evaluating the change in the kinematic free response for a torque pulse input in mechanisms and mechanical systems. Therefore, two generic four-bar mechanisms were analysed, doing the initial flywheel sizing based on the energy variations in one revolution of the system by a developed method of integration and stipulating a coefficient of fluctuation in the recommended intervals. The changes in the angular velocities were obtained by the power spectral density (PSD) with Welch's method, varying the number of points of the fast Fourier transform (NFFT), evaluating the magnitude (PSD) and frequency changes by a created C-coefficient, considering both. For coefficients close to the natural, no relevant frequency change was observed, compared with the magnitude changes, also noting that the C-coefficient changes exponentially when it is distant from the natural value, without flywheel. Significant changes were computed showing the sensitivity of the method, stabilising with the increase of the NFFT. For the integration method for flywheel sizing, a good result was obtained with small angle steps and small torque curves, obtaining an error of 0.00001 in the case of study. [ABSTRACT FROM AUTHOR]

In this paper, the performance characteristics of an ejector-expansion refrigeration cycle using six low GWP alternative refrigerants for R134a are presented through the first and second laws of thermodynamics. The ejector is modelled by assuming a constant-mixing pressure. The investigated refrigerants are compared based on the optimum ejector area ratio, discharge temperature, volumetric cooling capacity (VCC), coefficient of performance (COP) and exergy efficiency (ηex). The drop-in analysis is considered based on the same operating/designing parameters, and the VCC, COP and ηex improvements over the conventional refrigeration cycle are presented. The improvements in COP and VCC are between 7.914%–18.46% and 5.712%–22.82%, respectively, for the investigated range of evaporating and condensing temperatures. These values are higher than that of R134a by about 21% and 16%, respectively. The VCC using R1234yf is very close to R134a with a maximum reduction of 6.5%. Therefore, R1234yf refrigerant appears to be the best alternative to R134a in an ejector-expansion system with an appreciable COP and ηex devaluation. R152a outperforms R134a in terms of COP and ηex, thus it is a suitable alternative to R134a except for safety. [ABSTRACT FROM AUTHOR]

This paper presents an experimental study of the effectusing LPG instead of gasoline fuel on single-cylinder spark-ignition engine characteristics. The experiments were carried out at different engine loads and variable engine speed of (2400–3600) rpm. Significantreductionin brake specific fuel consumption by (5.42%)when LPG fuel was used as compared to gasoline. The use of LPG leads to a decrease in volumetric efficiency and brake thermal efficiency. The concentration CO and CO2 emissions is decreased by (11.54%, 14.4%) respectively with LPG compared to gasoline, except for the concentration of NOx, which increases by (10.8%) due to higher cylinder pressure and temperature in the case of LPG fuel compared to gasoline. The obtained results are validated with the same case study numerically with the help of simulation software Diesel-rk as well as with the results of other researchers. [ABSTRACT FROM AUTHOR]

The miniaturisation of systems has widely attracted researchers to contribute to the thermal performance enhancement utilising efficient heat transfer devices. Pulsating heat pipe (PHP) is an inimitable passive two-phase energy conversion/transport device capable of transferring extensive heat energy by oscillating liquid slugs and vapour plugs from hot to cold areas suitable for the management of generation of heat in electronics. Several theoretical, experimental and visualisation studies are made on PHP to understand operational mechanisms and to arrive at optimal conditions. Although PHP has potential application in the field of heat management, its effective utilisation is limited due to complex operational mechanisms.It is observed that PHPs are effective and reliable devices for utilisation in numerous energy systems. It is observed that PHPs are effective and reliable devices for utilisation in numerous energy systems. Advanced research is directed towards numerical simulations on the evaluation of PHP performance with non-conventional working fluids. It is found that the use of ternary hybrid nanofluid in PHP has scope for research work. The objective of this paper is to review the existing methodologies for enhancing the PHP overall performance and its applications. [ABSTRACT FROM AUTHOR]

In this paper, surface roughness prediction models are developed for turning of Inconel 718 using untreated and cryogenically treated inserts by using Dimensional Analysis, Response Surface Methodology (RSM) and Artificial Neural Network (ANN). Performance of untreated and treated tools is analysed using SEM, Energy-dispersive X-ray analysis, Vicker hardness test and electrical conductivity. For the established surface roughness models by dimensional analysis, RSM and ANN, the mean absolute errors for confirmation tests are 5.32%, 8.28% and 4.15% for untreated inserts and 4.95%, 6.01% and 4.20% for treated inserts, respectively. The effect of cutting parameters on surface roughness is analysed using the main effect plot and 3D surface plots. Based on correlation coefficient (R2) values, ANN modelling technique (R2 = 99.68%) is more accurate for predicting surface roughness. Thus, it can be an effective tool for analysing machining responses. The study also noted that while cutting at v= 60 m/min, f= 0.1 mm/rev and d= 0.5 mm, surface roughness and flank wear values are 0.5 µm and 0.45 µm and 0.777 mm and 0.627 mm for untreated and treated inserts, respectively. The use of treated tools resulted in 10% and 19% improvement in surface quality and tool life than the untreated tools. [ABSTRACT FROM AUTHOR]

Modern industrialisation and the need for low-density material initiated the up-gradation of material for the necessity of sustainability, and the same goes for engineering materials as well. Right from ancient times, composites have an important place in the field of engineering materials, but now demand for such materials, especially fibre-reinforced polymer (FRP) composites, proliferates just to improve the quality of materials as well as the quality of life. The present work provides a comprehensive literature review on hybrid FRP composites, techniques involved in its fabrication, machining and variation in mechanical properties due to hybridisation. The main focused fibre-reinforced composite are glass fibre, carbon fibre, basalt fibre and Kevlar fibre-reinforced polymeric composites. The paper includes recent work that showcases the hybridisation behaviour and their field of application. [ABSTRACT FROM AUTHOR]

The purpose of this research is to demonstrate the use of a new and highly efficient population-based algorithm, known as Heat Transfer Search (HTS), for optimisation of an active magnetic bearing (AMB) system. In this research paper, the HTS algorithm is employed to minimise the overall bearing volume, considering turns per pole pair, the maximum required current, pole width, and coil length as the design variables. Constraints are imposed on the maximum flux density, current density, winding space, and maximum magneto-motive force. It is found that, for the operating conditions considered herein, the Heat Transfer Search algorithm yields around 23% lower bearing volume as compared to that obtained using more popular optimisation techniques such as Genetic Algorithms (GA) and Pattern Search (PS). Finally, a comparative study on the impact of magnetic core material presented herein reveals that Supermendur yields the best results. This is the first attempt to integrate the impact of magnetic core material on the optimisation of the AMB system. [ABSTRACT FROM AUTHOR]

The lock valve plays an important role during normal shift and power failure in heavy-dutyautomatic transmissions. A new kind of lock valve was designed in this paper, and the main purpose of this paper is to improve the working performance of the lock valve. Firstly, the AMESim simulation model of the lock valve was built based on the analysis of the working circuit of the lock valve, and the influence of several design parameters on the lock valve working performance were analysed, which provided a reliable theoretical basis for the subsequent optimisation research. Additionally, thecomplete second-orderresponse surface model between design parameters and output oil pressure response time and control oil pressure fluctuation is established based on ISE and ITAE criteria. Finally, the particle swarm optimisation(PSO) algorithm and Box-Behnkenresponse surface methodology were applied to the optimisation of the mathematical model. The optimisation results have shown that the two optimisation methods can significantly improve the output oil pressure response speed of the lock valve, but the optimisation results of Box-Behnkenresponse surface methodology are more stable than the PSO algorithm in the control oil pressure, and the growth fluctuation is smaller. [ABSTRACT FROM AUTHOR]

This paper presents a four-fingered robotic hand, designed to carry out grasping operations along with different object manipulation tasks. The design of this hand resembles a human hand which is the perfect dexterous robotic gripper. In this paper, the forward kinematics of the designed hand is carried out using the Denavit-Hartenberg (D-H) parameters, to calculate the position and orientation of each of the fingertips. Inverse kinematics of the hand is formulated to compute the different joint angles for different fingertip configurations. Kinematic simulations are realised to estimate the workspace of the four finger robotic hand using the MATLAB interface. All possible fingertip trajectories are plotted in joint space to determine the motion constraints of the developed hand model. The results obtained confirm that the hand is suitable for grasping objects of variable geometry and materials within its workspace. The motion of the fingers is flexible enough for different object manipulation. These analysis shows that this hand is capable to perform the desired tasks successfully. [ABSTRACT FROM AUTHOR]

Abrasive water jet machining (AWJM) is an unconventional cutting method used in different industrial applications. The motive of this paper is to investigate the effect of traverse speed on surface roughness for a particular workpiece thickness. Three different plates of AISI 1030 steel as work-piece with thicknesses 4 mm, 6 mm and 8 mm are used to evaluate surface quality of cutting. Three response models for respective thicknesses are generated and checked on the basis of their prediction ability. It showed 8.71%, 8.11% and 7.83% error for surface roughness for three different thicknesses, respectively. Post validation, desired surface roughness values are placed in the response models for prediction of respective traverse speeds for three different thicknesses and represented in a graphical manner. This paper will help the AWJ machining operator to find out the precise cutting speed for achieving desired surface roughness. [ABSTRACT FROM AUTHOR]

This paper presents a hybrid method, validated through a series of experiments for balancing of rigid and flexible rotors at a constant rotational speed. Unlike existing balancing methods, this hybrid method combines the benefits of the 4-runs method and the Influence Coefficient (IC) method without requiring a response phase measurements to estimate three correction weights so as to minimise rotor balancing errors. The proposed method requires three trial runs without phase measurements to localise the position of unbalance using the centroid concept. Then, calculating the phase angles of each trial run to apply, three times, the IC balancing method. Finally, estimating the overall corrective weight from these three correction weights. A comparative study was used to verify the reliability of this hybrid method as a contrast test. Additionally, two experimental cases were designed to evaluate the method in two different operating environments. Experimental analyses show that the proposed method presents acceptable results, despite the use of a modest instrument such as the smartphone to acquire the vibration signal of the unbalanced rotor. In this context, this paper highlights the opportunities behind smartphones, which can be a reliable tool to perform professional operations such as field balancing for rotating machinery. [ABSTRACT FROM AUTHOR]

Transient stress and deformation analysis of a functionally graded rotating cylinder made of Al-Sic with short length under thermal and mechanical loads is studied in this paper. It is assumed that the cylinder is located on a friction bed and is subjected to an external torque. The material property is assumed to be variable along the radial direction based on volume fraction distribution. Thermal conductivity equation with time parameter is solved to obtain temperature distribution by Finite Difference Method. First-order shear deformation theory is used to derive kinematic relations. The governing equations are derived using minimum total potential energy and Euler relations. These governing equations are solved using the method of Eigenvalue and Eigenvector. The physical and loading boundary conditions are applied to obtain unknown coefficients. As the main result of this paper, it is concluded that the radial displacement is uniform at the middle of a cylindrical shell and is decreased to zero with an increase of axial coordinate. [ABSTRACT FROM AUTHOR]

Artificial intelligence (AI) techniques are a reality in the most diverse engineering research and, intuitively, the same is true for automotive development. Meanwhile, driver-in-the-loop (DiL) simulation allows researchers to develop and test different vehicles and correlated systems without the need to build physical prototypes. Considering the increasing goal of reducing cost, project time, and most importantly the impact on the environment, the advantages of DiL simulation become even higher. In this scenario and given the growing need for analysis of considerably large sets of data obtained especially by the use of simulators, the present work undertakes a literature review regarding the use of artificial intelligence in driver-in-the-loop simulations. To do so, some keywords are defined as some boundary conditions also are, e.g. how old the paper is aiming not to consider outdated tools and technologies. Passing through three eliminatory revision steps, the full text of the final selected works is read with the aim to define where the research that uses IA and DiL simulation is aimed. The findings suggest that most of the works use the aforementioned tools to develop autonomous vehicles and their correlated systems. Finally, a discussion about this result is proposed and then a guideline for amplifying the reach of the present literature review is suggested. [ABSTRACT FROM AUTHOR]

In view of the current design idea of elastic rubber gasket of shield tunnel segment jointsbased on experience, a numerical simulation method is proposed.By adjusting the area and position of the circular hole,the reasonable deformation of gasket holes under compression,the stress concentration at weak parts,the amplitude and distribution of contact stress under the maximum opening amount,the pressure amplitude when the gasket is fully compressed into the groove and the compression deformation curveare analysed comprehensively, and finally three improved sections are obtained.The results show that both the composite section improved by section 1 and the single section improved by section 3 have good waterproof ability.However, considering the adverse factors, such as the quality difference of water swellable rubber due to water absorbent resin and other swellable materials in practical use, the decrease of elastic deformation property of base materials after swelling and the dissolution of swelling agents, the improved section 3 witha single type has a wider applicability.The originality of this paper lies in systematically discussing the improved schemes of elastic rubber gaskets by combining stress state and reasonable deformation. [ABSTRACT FROM AUTHOR]

Turning is a drastically favoured machining process for producing cylindrical components with required dimensions. Prediction of chip formation is essential when damages caused by chips are into consideration during machining. A high amount of residual stresses are generated in the machined component due to a large number of forces and temperature distribution during machining. The scope of this paper is to investigate the percentage of residual stresses induced in a component during the dry micro turning process. Hence, in this work, Inconel 718, A2024-T351, and AISI D2 (62HRC) are selected as a workpiece materials and WC as tool material, simultaneously comparison studies of chip morphology have been carried out. Also, cutting speed and power consumption were investigated experimentally by opting varied tool rake angles (positive, negative, and zero) and a depth of cut. Residual stresses, nose wear, and chip morphology were found experimentally while machining Inconel 718. From the simulation and experimental results obtained, one can adopt a suitable tool rake angle to minimise power consumption during the micro turning process which leads to a sustainable machining process. [ABSTRACT FROM AUTHOR]

This paper presents the machining characteristics of AA6061/(0–9 wt%) ZrB2+ ZrC aluminium metal matrix composites using polycrystalline Diamond(PCD). In the present investigation, AMCs were fabricated by in situ reactions between K2ZrF6, KBF4 and SiC particles. The electric stir casting furnace was used to fabricate the AMCs under a controlled environment. X-ray diffraction patterns (XRD) and field emission scanning electron microscope (FESEM) were used to ascertain the formation of ZrB2 and ZrC particles in the AMCs. FESEM micrographs confirmed the uniform distribution of ZrB2 and ZrC particulates along with good interfacial bonding with matrix aluminium alloy. The effect of varying wt% of ZrB2+ ZrC along with cutting speed, feed and depth of cut on machining forces and surface roughness were analysed. FESEM was used to study the morphology of cutting tool, machined surface and chip formation. It was observed that cutting forces reduce with increase in cutting speed due to decrease in built-up edge (BUE) formation and deprivation of dislocation density. The tool wear increased with increase in cutting speed, depth of cut and ZrB2 + ZrC content due to the increase in abrasive action of ceramic particles and reduction of stable BUE. [ABSTRACT FROM AUTHOR]

This paper aims to determine the effect of contact geometry on temperature distribution and thermal buckling in an in-wheel brake system. Numerical analysis is conducted to investigate the variation of temperature field distribution on the brake disc a different cover angles of the pad while maintaining the same moment of friction. Also, different positions of the pads on the disc are considered. To verify the simulation results, an analytical solution is derived. The results show that, for the same work done by the pads on the disc, the resulting temperature field distributions have various effects on the disc. Moreover, certain contact geometry was found to cause the braking temperature to exceed the critical temperature, leading to thermal buckling of the disc during braking. [ABSTRACT FROM AUTHOR]

The performance of the aircraft fuel tank inerting system is influenced by multiple factors which are strongly coupled. It is a time-consuming process to analyse and evaluate the performance of the system through experiments, and it is difficult to analyse the effects of various factors through limited experimental data. An efficient numerical method is significant for the preliminary design and optimisation of inerting products. In this paper, a generic mathematical model of the hollow-fibre-membrane module (HFMM) was established and the accuracy of the numerical results was verified using experimental data. Based on this mathematical model, a simulation model of the aircraft fuel tank inerting system was developed through cosimulation of AMESim and Matlab/Simulink. The accuracy and applicability of the simulation model for this inerting system were verified using experimental test data. Using this simulation model, the effect of nitrogen-enrich air (NEA) flow rate and aircraft flight altitude on the performance of the inerting system were investigated. The results show that increasing the NEA flow rate contributes to a shorter time for the oxygen concentration to reach a steady state while with a higher stabilised value. The use of a high NEA flow mode is effective in improving the inerting performance during the rapid descent stage. [ABSTRACT FROM AUTHOR]

In this paper, free vibration analysis of truncated conical shells reinforced with graphene nanoplatelets (GNPs) is studied. The composite shell is considered to be composed of epoxy reinforced with GNPs distributed along the thickness direction based on the various patterns. The shell is modelled based on the first-order shear deformation theory and effective material properties are calculated based on the Halpin-Tsai model along with the rule of mixture. The set of governing equations and boundary conditions are derived using Hamilton's principle and are solved numerically using generalised differential quadrature method for all possible combinations of clamped, simple and free conditions. Convergence and accuracy of the presented solution are confirmed and influences of various parameters on natural frequencies of the shell are investigated including boundary conditions, semi-vertex angle, circumferential mode number and also total mass fraction, width, thickness and distribution pattern of GNPs. Due to excellent mechanical and thermal properties of GNPs and wide application of conical shells in modern industries such as pressure vessels, aerospace structures and piping, results of this paper can be valuable and useful. [ABSTRACT FROM AUTHOR]

The purpose of this paper is to predict the maximum pressure of journal bearing using ANN. The maximum pressure values are analysed using FEM and predicted using ANN. The FEM analysis is performed for micropolar lubricated hybrid journal bearing, and the results are used for training and testing the ANN model. Feedforward backpropagation algorithm is used for ANN model development. The externally applied load and rotational speed of the journal are considered as input parameters for performance predictions. ANN predictions are made within and outside the prescribed range of input parameters. This approach shows better predictions for journal bearing performance. Results obtained from FEM and ANN are in close agreement with each other. The percentage error less than 0.5 is observed for training and testing of the ANN model. The prediction error is in the range of −0.6% to 0.48%. In this paper, a mathematical model is established using FEM. The performance predictions obtained using ANN are very useful because much time can be saved which would be otherwise consumed in the experimental or theoretical bearing analysis. [ABSTRACT FROM AUTHOR]

The main aim of this research is to increase a low water flow rate of 1 l/m up to a minimum of 6 l/m using a TapBoost pump. This pump will be used to support poor domestic flow rates in the UK & ROI. TapBoost was developed without the need for mechanical seals by using wet rotor technology making it the most efficient water boosting pump in Salamander’s pump range. The various stages of design, testing and development of the TapBoost pump are reported in this paper. TapBoost is an inexpensive solution to improve the water flow rate given from a trickling single outlet anywhere in a domestic setting. TapBoost has been specially designed to be easily installed onto any existing or new water mains pipework. The main conclusions are as follows: i) the TapBoost was successfully designed, manufactured, tested and launched in March 2022, meeting the specification requirements given by Salamander Pumps to develop and launch this new product, ii) The results showed that the pump delivers a boosted water flow rate of 6.75 l/m compared to the original water flow rate, without the use of the pump, of just 1 l/m, iii) The performance of the TapBoost is better than the leading competitor in the market. [ABSTRACT FROM AUTHOR]

This paper presents a numerical investigation of the three-dimensional dynamics of droplet impact on a thin liquid substrate using the lattice Boltzmann method (LBM). The LBM solver is employed to simulate the fluid dynamics of the droplet-substrate interaction and the subsequent formation of waves on the substrate surface. The study specifically focuses on the influence of Weber number on the collision dynamics between the droplet and substrate, as well as the resulting wave patterns. The simulation results provide insights into the behaviour of the droplet-substrate interface, including the formation of a ‘neck’ region and the fluid recirculation around it. Moreover, the study examines the impact of Weber’s number on the amplitude and frequency of the resulting waves. This research holds significant implications for applications in microfluidic and microelectromechanical systems (MEMS*), where a thorough understanding of droplet impact dynamics is crucial for the design and optimisation of inkjet print heads and other droplet-based systems. By offering an in-depth understanding of the droplet-substrate interaction, this study contributes to the development of more efficient and precise droplet production systems. [ABSTRACT FROM AUTHOR]

The herringbone gear power-split transmission is widely used in high-speed and heavy-load transmission systems, and its dynamic analysis is becoming increasingly important. The characteristic sensitivity of a gear transmission system indicates the influence of the dynamic parameters on the natural frequency of the gear transmission system, and it functions as an important theoretical reference value in the dynamic design of a herringbone gear power-split transmission system. In this paper, the dynamic equations of a herringbone gear power-split transmission system for a ship are presented, and the natural frequencies and modal shapes are calculated based on the free torsional vibration differential equation. Subsequently, the modal shapes were classified into the coupling vibration model and the branch vibration model. The characteristic sensitivity was studied using modal analysis, and the characteristic sensitivity calculation equations for single and double root of natural frequency were deduced, and the characteristic sensitivity of the natural frequencies to the mesh stiffness was computed. Finally, the relationship between the modal strain energy and the characteristic sensitivity was analysed, and the physics essence of the characteristic sensitivity was revealed. [ABSTRACT FROM AUTHOR]

Base pressure is a crucial component in the measurement of flow parameters in a high-speed aerodynamic flow. In this paper, the microjets impact as a control mechanism is experimentally tested for the nozzles with abrupt expansion at supersonic Mach in an axisymmetric conduit. The flow regulation mechanism is placed at a 90-degree interval in the shape of an orifice of 0.5 mm in radius along the nozzle's exit diameter, which generates jets at sonic Mach numbers. The flow constraints studied are inertia level (Mach number), expansion level (NPR), and the geometric parameters considered are the pipe's length (L/D). These three relevant parameters were selected for design of experiments (DOE). In the management of base pressure, this analysis's primary objective is to evaluate the parameters influencing the flow. The experiments were carried out in two ways: without and with microjets. For the DOE, an L27 orthogonal series, polynomial expression, analysis of variance, and predicted plots were carried out to test the experimental findings. The established prototypes are statistically appropriate and achieved when making precise projections for all the cases. According to the present results, the L/D ratio for a given parameter is the most critical parameter influencing the maximum increase or decrease in the base pressure. [ABSTRACT FROM AUTHOR]

The brake system of a mine hoist is the key component and the last barrier to ensure the safe operation in a mine. Based on the vibration and the sound signals of a test brake system, this paper studied the characteristics of the signals and the relationship between both the signals and tries to propose a new fault diagnosis method for the brake system. First, the vibration and sound signals of the test set-up under different braking conditions at different brake disc rotation speeds were collected. Then, the vibration and sound signals were filtered and reduced by the wavelet packet, and the reconstructed signal eigenvalues were extracted. The results showed that the characteristics of vibration and sound signals in fault state and normal state can be drawn. It shows the combined fault diagnosis method based on vibration and sound signals can see a wide application to the fault diagnosis for mine hoist brake system. [ABSTRACT FROM AUTHOR]

The current paper deals with the exact solution of vibration analysis of functionally graded (FG) annular plate elastically restrained boundary conditions and resting on Winkler foundation. Hamilton's principle has been applied to derive the motion equations of FG annular plate and associated boundary conditions based on the classical plate theory (CPT). It is assumed that the material properties have been graded through the direction of plate thickness according to power law distribution. The effects of some key system parameters such as normalised inner radius, non-dimensional foundation stiffness, non-dimensional transverse and rotational spring constants of the elastic boundary, volume fraction index and number of nodal diameters on the frequency parameter have been assessed in tabular and graphical forms. The accuracy of the present work has been validated by comparing the present results with those computed by previously published literatures. [ABSTRACT FROM AUTHOR]

This paper uses the principles of polarisation to calculate the Stokes component of the polarisation image. It designs the spatial weighted fusion algorithm, focusing on the research and evaluation of the accuracy and time complexity of the spatial weighted fusion algorithm in the polarisation image fusion processing. The spatial weighted image fusion algorithm is used to fuse the polarisation degree image, the polarisation angle image, and the light intensity image. Finally, the algorithm function is realised through software programming to verify the effect and accuracy of the algorithm. Experimental results show that the spatial weighted fusion algorithm can keep the pixel value of the polarisation source image unchanged, avoid image distortion, artefacts and ringing effects algorithm is stable and efficient, with low time complexity. [ABSTRACT FROM AUTHOR]

This paper investigates free vibration of cracked single-walled carbon nanotubes modelled as Timoshenko nanobeams under axial thermal load. The main objective of this work is a deep, true, and precise formulation to analyse truly the thermal effects on the Timoshenko nanobeam model. Nonlocal elasticity theory is applied to Timoshenko beam model. It is assumed that a crack divides the beam into two segments. The crack is modelled by a torsional spring connecting the beam segments to each other. The thermal load acts as an axial force on the nanobeam. Galerkin's method is used to solve the partial differential equation of motion. The effect of the crack location, crack severity, thermal load, and nonlocal parameter on the frequencies are examined. As the crack severity increases, the frequencies decrease except the modes in which the crack locates at one of their nodes. All mode frequencies decrease at the high temperatures and increase at the low temperatures. Increasing the nonlocal parameter causes a reduction in the frequencies at any temperature. The nonlocal parameter effect on the frequencies increases at high or elevated temperatures. [ABSTRACT FROM AUTHOR]

Heat exchangers have found extensive applications in the engineering sector owing to the crucial need for heat transfer and temperature regulation in the process industry. The performance analysis of a heat exchanger can either be investigated experimentally or utilizing computational fluid dynamics (CFD). The simulation of flow conditions based on CFD principles is considered as a contemporary approach for conducting performance analysis and design optimization of the heat exchanger. The paper aims to present how the performance optimization parameters of shell and tube heat exchanger effect its performance in terms of the extent of heat transfer achieved and fall in the shell outlet temperature. A standard model (Model 1) was initially defined, and seven subsequent models were created with one varying parameter as compared to Model 1 to carry out the comparative analysis. The results showed that decrease in inlet velocity, increase in thermal conductivity of the heat exchanger material, reduction in baffle spacing and use of triangular tube bundle arrangement has significant influence on the reduction of the condensate temperature. The effects of the same parameters on the temperature distribution and heat transfer rate have also been discussed. [ABSTRACT FROM AUTHOR]

In this paper, based on Euler-Bernoulli beam theory, the vibration of a helicopter blade is studied. In this regard, the partial differential equation of motion is obtained and solved for a clamped beam numerically. The aerodynamic forces are introduced in terms of the pilot parameters included the collective pitch, lateral cyclic, longitudinal cyclic, and built-in twist on the blade deformation. Moreover, the effects of the blade rotational angular velocity, flight altitude, the blade length, and induce velocity on the blade deflection are studied. The results show that the blade deformation will be oscillating in terms of time and it is very sensitive to the control parameters, its geometry, and the environmental conditions. Moreover, it is observed that the pilot coefficients have more effect on the blade deformation in comparison with other parameters. [ABSTRACT FROM AUTHOR]

The paper explores the potential study of artificial neural network (ANN) for prediction of response surface roughness (Ra) in face milling operation with respect to cryogenic approach. The model of Ra was expressed as the main factor in face milling of spindle speed, feed rate, depth of cut and coolant type. The ANN is trained using four various back propagation algorithms (BPA). The emphasis of the paper is to investigate the performance and the accuracy of the attained results depicts the effectiveness of the trained ANN in identifying the predicted Ra. The incorporated various BPA in predicting the Ra. The performance comparative study is made among statistical (Response Surface Methodology (RSM)) and ANN (BPA – training algorithm) methods. The various incorporated BPA algorithms are Gradient Descent (GD), Scaled Conjugate Gradient Descent (SCGD), Levenberg Marquardt (LM) and Bayesian Neural Network (BNN). Afterwards the best suitable BPA is identified in predicting Ra for AISI 316 in face milling operation using liquid nitrogen (LN2) as cutting fluid. The outperformed BPA is identified based on the attained deviation percentage and time required for the training the network. [ABSTRACT FROM AUTHOR]