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This book comprises select papers presented at the International Conference on Mechanical Engineering Design (ICMechD) 2019. The volume focuses on the recent trends in design research and their applications across the mechanical and biomedical domain. The book covers topics like tribology design, mechanism and machine design, wear and surface engineering, vibration and noise engineering, biomechanics and biomedical engineering, industrial thermodynamics, and thermal engineering. Case studies citing practical challenges and their solutions using appropriate techniques and modern engineering tools are also discussed. Given its contents, this book will prove useful to students, researchers as well as practitioners.

### Rigid Logged Coupling: An Improved Coupling with Less Material and Low-Stress Concentration

The paper is about a new coupling design that can be used to connect two shafts in the same line without any axial or angular misalignment. The goals of the new design are to reduce the amount of material required to produce other couplings and reduce the chances of failure due to different stress distribution patterns. Rigid flanged coupling is used as a reference for comparison. The design consists of mainly three parts body, pins and logs (strips of metal used to connect the body). The holes are done on outer surfaces of the hexagonal or a square prism of each body while one surface of each body faces each other. The logs are used to join the two bodies with the help of pins in the holes. The coupling is designed using Autodesk Fusion 360. Proper mathematical analysis of the couplings is done to get the difference in the material used. This design can be used to connect both, shafts with the same diameter or shafts with different diameters. The design has less stress concentration around holes and in whole design in general and is similar in the manufacturing process as the presently available couplings. For the safety of the operator or user, the coupling is covered with a protective case to avoid the failed parts (if any) to hit the operator or the user. The dimensions are found using stress analysis and considering the modes of failure for each section of the part. Shear and tensile failure have been considered at the parts of the assembly. The bending effect has also been considered for parts wherever adequate. The stress analysis results have also been found out using Autodesk Fusion 360. To observe the effects and results of stress analysis, similar working conditions have been simulated with the coupling designed in Autodesk Fusion 360.

Aniket Modak

### An Efficient Grey Water Stagnancy Handler

This work proposes the idea of “Human hair boom skimmer” in addition to the conventional flow grey water treatment. The conventional method of treating grey water doesn’t pose a promising solution in reducing the amount of oil content from it. Rather than discarding the human hair, it can be used to absorb the oil from the grey water. The oil adsorption capability of wasted hair fibers could produce valuable solutions for our prevalent and modern society. Our concept “An Efficient Grey Water Stagnancy Handler” concentrates on three major phases: Phase-1, deals with the drastic problem being faced by the surrounding environment with slip and falls due to the improper collection of grey water from the bathroom floors, Phase-2 address the eco-friendly and cost-efficient methodology to treat the grey water, Phase-3 tackles the dwindling water resources for crops cultivation by the diversion of processed water to the required place wherein immediate need of it. Thereby, the grey water from the bathroom sink is no doubt a valuable resource that can be used to alleviate the water shortage problems and increase water conservation in individual households. Therefore, an alternative eco-friendly method rather than the conventional method as mentioned above could pose a firm solution.

K. Banumalar, M. Aiswarya, M. Asvanthini Eswari, M. Karthika

### Experimental Design and Testing of Scale Development Reduction System in Domestic Water Geysers

The aim of this project is to reduce the extent of scale formation in domestic water geysers with minimal investment that is efficient in cleaning and can be commercialized for consumer use. Modern water geysers have the disadvantage of a life of maximum of one year due to formation of scales on the heating coil and the walls of the geyser thereby reducing the efficiency of boiler and decreasing the life of geyser. The geyser is to be fitted with a 3D printed polymer float bounded by a soft brush. The variation in level of water inside the geyser will cause up and down movement of the float, brushing the internal wall of the geyser removing any salt presence. A nozzle system will be activated during the manual cleaning phase to provide a more efficient cleaning for the internal parts of the geyser and to wash away the salts from the brushes while drain them through a separate pipe. A valve system controls the direction of flow of fluid during the cleaning. The testing was done for a period of 240 days. The results showed a significant improvement in the performance of the geyser and reduced the extent of scale formation.

Kabilan Sankar, Karthick Selvam, K. Joy Ashwin

### Transient Analysis of Rotor System

This paper introduces a transient vibration investigation of horizontal rotor system with three distinctive disk positions mounted on a shaft, for the simply supported case. The material properties of the shaft and disk are the same. A transient analysis is performed to obtain the amplitudes for three distinctive disk positions. A force is applied on the disk for a small time frame. Design a dynamic rotor structure; it is essential to decide the vibration parameter, i.e., natural frequency, critical speeds, and amplitudes. The transient analysis was performed by “ANSYS” parametric design tool. The results obtained from the analysis are helpful for the design of the rotor system.

D. S. Megharaj, Amit Malgol

### Investigating the Contact Load Capacity of Asymmetric Helical Gears

Gears are one of the machine elements used to transmit a torque from one point of application to another point of application of a mechanical system through the shaft. In many applications, the power flow is unidirectional. In this case, asymmetric gears preferred over the symmetric gears. The present work focuses on evaluating the contact stress through finite element analysis for the symmetric and asymmetric helical gears. To calculate the stress between the contact points of the gears the Lagrange multiplier algorithm is applied. Probable increase in the percentage of contact load capacity of asymmetric helical gear is measured and is duly compared with values obtained for symmetric helical gear.

P. Dinesh Babu, Swathi Balaji, P. Marimuthu

### Close-Proximity Dynamic Operations of Spacecraft with Angles-Only Rendezvous in a Circular Phasing Orbit

Through this paper, it is to assess a closed-loop guidance algorithm for the range of observability of angles-only by rendezvous position and proximity operation. The prominence and influence of Clohessy–Wiltshire dynamics (CWD) is an emerging area which deals with angles-only guidance coupling algorithm and relative position. Observability analysis of the of rendezvous at a low earth circular orbit, as opposed to one spacecraft remaining fixed in its orbit, and the implications for total times are expended. A closed-loop guidance design scheme is generally based on unscented Kalman filter (UKF) and coupling relationship. The proposed method is used in the analysis and the following results are obtained for an initial separation, initial state uncertainties, line-of-sight angles correctness and ΔV (change in velocity) from the navigation and guidance accuracy. The novelty of the approach is to minimize the delta-V for close-proximity operation in phasing spacecraft to the other.

Thangavel Sanjeeviraja, R. Santhanakrishnan, S. Lakshmi, R. Asokan

### Optimal Dimensional Synthesis of Rhombus Path Generating Adjustable Four-Bar Mechanism

Precise and continuous generation of rhombus path by adjustable four-bar mechanism is investigated and confirmed using Reconstructed Adjustable Parameter Curve (RAPC) technique. RAPC method is able to extract adjustable parameter value of intermediary path points along the path generation profile corresponding to uniformly incremented crank angle values. Harmonic Spacing (HS) algorithm is used to improve the precision points spacing along the perimeter of intended rhombus path. Optimal dimensional synthesis of adjustable four-bar mechanism makes use of these precision points. Simulation of motion of adjustable four-bar mechanism to generate profile path of rhombus is carried out to verify the dimensional synthesis of the linkage. Optimization combining Genetic Algorithm (GA) and Pattern Search (PS) is implemented to synthesize rhombus path generating mechanism. Results show the achievement of precise and continuous path generation with high accuracy for the selected rhombus path profile.

Ganesan Govindasamy, Rajakumar S. Rai, Gadudasu Babu Rao

### Sensor Fusion for Automotive Dead Reckoning Using GPS and IMU for Accurate Position and Velocity Estimation

In recent years, detecting the position of the vehicle is an important task. The goal of detecting the position of the vehicle can be achieved using Global Positioning System (GPS) technology by getting approximate position data of the ego-vehicle. For better and accurate positioning, automotive dead-reckoning can be used. Automotive dead-reckoning (ADR) technology is a high-end navigation system. In this paper, an ADR is used to calculate the position based on the distance and direction of the vehicle traveled from the last known location. This gives an accurate estimation of the 3-axis position and velocity components based on vehicle data retrieved from GPS and Inertial Measurement Unit (IMU) sensor. ADR not only allows full coverage in indoor car parking, tunnels, and underpasses but also effectively eliminates the impact of multipath effects in urban canyons. The vehicle is incorporated with sensors that record wheel rotation along with the steering direction and the sensors are allowed to take continuous measurements with the help of the last known location. The position and velocity shall be corrected even if quality GPS data is available. In case of partial GPS blockage, the estimation shall be done with different strategy/weightage factors. In case of complete GPS blockage, the prediction shall continue for some approximation time, with the help of vehicle and IMU sensor data. Finally, various experiments are conducted using Kalman filter and extended Kalman filter, and the prediction results are found to be satisfactory.

Lalith Prabu Nalla Perumal, Arockia Selvakumar Arockia Doss

### Optimal Dimensional Synthesis of Double-Semi-circle and Double-Semi-ellipse Path Generating Adjustable Four-Bar Mechanisms

Synthesis of adjustable four-bar mechanisms to generate continuous and precise path of double-semi-circle-straight-line (DSCSL) and double-semi-ellipse-straight-line (DSESL) path generation is investigated and verified. Harmonic spacing (HS) algorithm is used to improve precision points spacing along the intended profile paths. Bi-cubic interpolation is used to extract adjustable parameter value of intermediary path points along the profile of path generation conforming to uniformly incremented crank rotation value. Precision points are used in the synthesis to get dimensional values of link lengths and other parameters of adjustable mechanisms. Motion simulation of adjustable mechanism to generate intended coupler path profiles is carried out to verify the dimensional synthesis of the mechanisms. Pattern search (PS) is implemented in the synthesis of mechanism from the results of genetic algorithm (GA) as a hybrid method. Results demonstrate continuous and precise path generation of selected path profiles.

Ganesan Govindasamy, Gadudasu Babu Rao, Rajakumar S. Rai

### Effect of Interference on a Floating Axis Epitrochoidal Hydrostatic Unit

In the present work, the effect of inclusion of interference on the performance of an Epitrochoidal Hydrostatic Rotary Piston Machine, namely Orbit motor is studied by building its mathematical model and implementing the algorithm in MATLAB. In this approach, the rotor is rigid, rollers are elastic and interference between the rotor and the stator is provided by changing the roller radius, chordal thickness and the pitch circle radius. In an Orbit motor of interference-fit type, the contact points and the rotor center deviate from their original position as found in an Orbit motor of perfect-fit type. A corrective technique based on minimum potential energy of the system is used to obtain the rotor center of an interference-fit motor, starting from the geometrically obtained rotor center of a perfect-fit motor, correcting itself to its final position. For various positions of the output shaft, the forces and torque acting on the rotor are calculated. For positions other than those corresponding to that of maximum compression and maximum expansion of chambers, it is found that a net unbalanced torque acts on the rotor. This torque tends to bring the rotor back to the nearest position of maximum compression. Apart from the determination of the unbalanced torque, the variation of deformation and maximum contact pressure at the contact points between the rotor and the stator due to sole inclusion of interference, for the first two phases of the rotor rotation is also investigated.

Harish Ramachandran, Aditya Shriwastava, Abhijit Nag

### Design and Analysis of Rocker Arm Shaft in IC Engine Hino Series for Reduction of Assembling Dismantling Time

Nowadays, in automobile industries the major competition exists in the field of design and cost of any product. Automobile plays a vital role in our daily life. One of the important components of the automobile is the engine of the automobile. Assembling and dismantling of the engine are difficult and tedious process. It is considered as time-consuming process also. If it is in the case of any valve leak, valve bend or due to any abnormal combustion in the engine, then the total set-up of the engine is to be dismantled part by parts for reworking purpose. The engine involves the large number of parts, and it takes too much of time for removing them completely into individual part. For reducing the time consumption, “the replica of rocker arm shaft” is designed. By using this, whole cylinder head is dismantled from the engine without any major damage. The time consumption would be very less, comparing with the existing method. The ultimate aim of our project is to reduce the time consumption for dismantling and reassembling of engine, without any major damage to engine parts and other surrounding parts.

R. Iruthayaraj, S. Palani, R. Ajay Vishal, T. Living Rockson, K. Anand

### Kinematic Analysis and Dimensional Synthesis of Filleted-Rhombus Path Generating Adjustable Four-Bar Mechanism

Dimensional synthesis and kinematic analysis of adjustable four-bar mechanism to generate accurate and uninterrupted path of Filleted-Rhombus are investigated. Harmonic Spacing (HS) algorithm is used to improve the positioning of precision points along the intended profile path. Reconstructed adjustable parameter curve (RAPC) is employed to extract adjustable link length value of intermediary path points along the intended path conforming to an equally incremented crank rotation value. Simulation of motion of adjustable mechanism to generate the intended coupler path is carried out to verify the dimensions of the links and other parameters of the mechanism. Optimization employing Genetic Algorithm (GA) followed by Pattern Search (PS) is implemented using MATLAB codes in the synthesis of mechanism. Results show precise and continuous coupler path to generate filleted-rhombus profile and variation of kinematic parameters versus crank angle.

Ganesan Govindasamy, Clinton Wilson, K. Neeraj

### Experimental Investigations of Initial Push Forces on an Industrial Trolley

Manual material handling using push-pull trolleys in small- and medium-scale enterprises is an inevitable activity. A study carried out on a push-pull trolley using push-pull force gauge, surface electromyography, electro-goniometer, and heart rate monitor helped the researchers to find an appropriate handle height of a trolley for industrial use. Central composite design, a response surface methodology, was used for designing experiments. These experiments were carried out in a laboratory using five subjects with stature 1650, 1730, 1740, 1750 and 1820 mm, at 125 kg load under five different heights of handle, viz. 900, 950, 1000, 1050 and 1100 mm. A 35% of reduction was found in the initial forces after using 1100 mm handle height by the subjects during the pushing activity.

Masepogu Wilson Kumar, Gadudasu Babu Rao, K. Balasubramanian, I. Kantharaj

### Mathematical Analysis of Stiffness of Orthotropic Beam with Hollow Circular and Rectangular Cross-sections

Stiffness and strength of mechanical materials have to be thoroughly investigated to avoid functional and physical failures. This study investigates, analytically, the stiffness of wood beam, which is an example of orthotropic material, with different cross-sectional areas. The moment of inertia for each type of wood, considered, was analysed. The axial stiffness and bending stiffness were also computed for different cross-sectional areas. Comparisons were made and results are consistent with the ones in the literature. Specifically, it was observed that the cross-sectional areas of wood have a lot of influence on its mechanical properties. The axial stiffness, bending stiffness, shear stresses and moment of inertia of the orthotropic solid materials, considered, depend on their cross-sectional areas, to a large extent.

Michael C. Agarana, Esther T. Akinlabi, Anuoluwapo M. Olanrewaju

### Analytical Investigation of the Stiffness of Homogenous Isotropic Mechanical Materials with Different Cross-sections

In order to achieve the required high level of mechanical material components as regards sustainability and safety, the stiffness of such materials has to be thoroughly investigated to avoid failure. This study investigates, analytically, the stiffness of some mechanical materials with different cross-sectional areas, whose mechanical properties are homogeneous and isotropic. The exerted force for steel material solids with different cross-sections was investigated. Comparisons were made and results are consistent with the ones in literature. A computer software, Maple, was used to plot the three-dimensional graphs of the relationship between the parameters. Specifically, it was observed that the steel hollow rectangular beam cross-section has a high axial stiffness compared to that of steel hollow circular beam cross-section. Also, the moment of inertia of the steel beams, considered, depend on their cross-sectional areas.

Michael C. Agarana, Esther T. Akinlabi, Okwudili S. Ogbonna

### Fatigue Analysis of Vocal-Folds Using Discretized Aeroelastic Model

Voice disorders are common physiological challenges that arise largely due to vocal fatigue, i.e. fatigue of vocal folds and associated phonatory structures. Since the incurrence of fatigue in vocal folds directly depends on the qualitative and quantitative nature of the dynamical signature of vocal fold oscillations, the hitherto literature has resorted to estimating the time histories and stress histories of the vocal fold oscillations. Often, vocal fold dynamics are rid with different types of complexities. Therefore, the literature often resorts to the use of a mathematical model that closely resembles the human phonatory system. Modelling the mechanism of vocal folds as a two-mass model with 2DOF provides a reasonably accurate depiction of the same. In order to obtain the real-time histories of the vocal fold vibrations, a continuously changing parameter called phonation threshold pressure (PTP) is defined so as to describe the extent of accumulated fatigue. PTP can be determined numerically for a given set of physical and physiological parameters of the system. Since the vocal fold vibrations are of varying amplitude as time progresses, it is necessary to use a standard counting algorithm for fatigue analysis, like the Rainflow-Counting algorithm. Then, the incurred damage is computed with the help of a S-N curve and the Miner’s rule. With the time span of phonation as the control parameter and PTP as a continuously changing parameter, the responses of the system are systematically obtained. Later, comparisons on the fatigue damage are made.

Veda Samhitha Kanduri, James Emilian, Venkatramani Jagadish

### Response of a Layered Composite Beam Subjected to Static Loading Using Point Interpolation Meshless Technique

The present work proposes a meshless model to analyze the response of laminated composite beam under different types of static loading. The point interpolation method based on polynomial basis function is used for solving 1D higher-order beam theory equations. The distribution of transverse shear strain and stresses along thickness are obtained using Reddy’s shape function. A displacement response of a laminated beam is obtained for several lamination schemes, aspect ratio, and boundary conditions. The authenticity of the present algorithm is confirmed by comparing results with different cases from literature.

### Dynamic Behaviour of Laminated Composite Beam Undergoing Moving Loads

This study is about dynamic response of laminated composite beam undergoing moving loads. Rotary inertia and shear deformation effects are considered by using Timoshenko Beam Theory (TBT). Finite Element Method (FEM) is applied to discretize the structural element into space and for time discretization Classical Midpoint Rule with Midpoint Acceleration (MPR-MPA) is employed which is a part of Generalized Single Step Single Solve (GSSSS) family of algorithms. A MATLAB code is developed to obtain dynamic responses such as dynamic magnification factor and maximum dynamic deflection at the mid-span of simply supported isotropic and laminated composite Timoshenko beam. Numerical results are obtained and validated with the literature available and it shows good agreement.

### Demystifying Fractal Analysis of Thin Films: A Reference for Thin Film Deposition Processes

In this article, a variety of synthetic (or simulated) surfaces of various morphologies of thin films and their fractal analyses are presented. Similar scaling factors have been used to generate the synthetic images in GwydionTM software. The surfaces are based on the actual morphologies arising from various thin film deposition techniques. Using actual thin films of CdTe deposited by radio-frequency (RF) sputtering technique, we have successfully shown that the fractal analyses on the synthetic surfaces can be used to explain, theoretically, the development and self-affinity of various thin films. Based on this validation, the results of fractal analyses on different morphologies of thin films were generated using different fractal methods in Gwydion software. The methods used here include Minkowski functionals, height-to-height correlation, areal autocorrelation, and power spectral density functions. The article will be a good resource for explaining the fractal behavior and morphology of thin films arising from different deposition methods.

F. M. Mwema, Esther T. Akinlabi, O. P. Oladijo

### Dynamic Analysis of Rectangular Aluminum Plate Under Transverse Loading Using Finite Difference Algorithm

Aluminum is one of the most used mechanical elements in Manufacturing. This paper focuses on the analysis of its dynamic response of an Aluminum plate, under a moving load. The moving load, in this case, is assumed to be partially distributed. Rotatory inertia and damping effects were neglected, while the effect of shear deformation was put into consideration. Also, the rectangular Aluminum plate was supported by a simple form of foundation. A numerical algorithm–Finite difference was adopted in solving the mathematical model governing the deflection of plates under moving load under consideration. It was observed, among other results, that the maximum amplitude of the deflection of the Aluminum plate is a function of the contact area of the load and velocity of the moving load, which is in line with the results in the literature.

Michael C. Agarana, Esther T. Akinlabi, Michael O. Ikumapayi

### Ballistic Performance of Light Weight Magnesium (AZ31B) and Aluminium (AL 6061) Plates Using Numerical Method

Ballistic performance of lightweight Aluminium (Al6061) and Magnesium (AZ31B) plates has been determined using numerical method. In recent days, Aluminium and Magnesium plates are widely used in various structures because of their light weight and low density. Magnesium is 33% lighter than Aluminium and 77% lighter than Steel whereas Aluminium is one-third the weight of Steel. In the present work, the numerical ballistic performance has been investigated for different projectile velocity using ABAQUS finite element code to understand the impact behaviour, energy-absorbing capability and failure modes. The conical-shaped projectile was used and the plate thickness for both alloys was kept constant. The investigation has been done with three different velocities such as 100, 400 and 800 m/s. For the constant volume of Magnesium and Aluminium targets considered, lower depth of penetration and higher ballistic performance was observed for Magnesium target. The simulation result was verified by conducting a low-velocity impact test on the Gas Gun Test Setup and a good correlation was observed.

M. Selvaraj, S. Suresh Kumar, Ankit Kumar

### Comparison of Energy Absorption Characteristics of the Plain Fold and Spot-Welded Fold Tubes Under Three-Point Bending

Thin-walled square tubes are used as automotive vehicular crash structures since they can be easily constrained at the endpoints. These tubes are generally produced by costly extrusion process and special mold designs are required for making the same. This research work proposes a novel idea of making by folding thin metal sheets into square tubes that can be easily prepared, cost-effective and flexible in sectional shape. However, spot welding can be used to enhance the bending resistance and energy absorption. Bending collapse of tubes is one of the most important deformation mechanisms to be ascertained to ensure the safety of people or cargo under accidental crash events. Three-point bending tests are generally employed to investigate the bending characteristics and hence performed on plain folded and spot-welded fold tubes. Results revealed that spot-weld and number of turns have an important influence on the bending resistance of the folded tubes. The comparison between traditional tubes and welded tubes showed that the welded tubes outperform the traditional tubes in some aspects like minimizing the peak force and maximizing energy absorption. Adopting a number of turns further increased the bending resistance of the tubes compared with traditional square tubes.

### An Efficient Energy Absorber Based on Welded Fold Tubes for Automotive Applications

Thin-walled square tubes have proven their energy-absorbing capability in the automotive industries for safety applications. Unfortunately, special mold designs are required while making these tubes through extrusion process. This fabrication technique is in lack of flexibility or leads to low cost-effectiveness. In place of the existing extruded square tubes, this paper presents a novel energy absorber by folding thin metal sheets into tubes that are easily fabricated and cost-effective. However, it is unsafe to use these folded tubes directly due to its global buckling failure with low-energy absorption. Therefore, methods to improve the energy absorption characteristics of thin-walled structures have become essential. Spot and continuous welding are the effective joining techniques which can be used to enhance the energy absorption. In order to test the suitability of these tubes for crashworthiness, quasi-static tests were performed using a universal testing machine. The energy absorption capacity of these welded folded tubes was analyzed and compared with traditional square tubes with the same mass to quantify the relative merits. It was found that spot welding leads to a reduction in peak force and continuous welding leads to a reduction in performance due to its global bending. The results showed that the initial peak force of spot-welded tube is 10–15% lower than the continuous weld and 20–25% lower compared to the extruded square tube. Finally, it was found that spot-welded tubes had more crush length than that of continuous and plain folded one which leads to an increase in energy absorption. The outcomes of the present study would facilitate the design of welded tubes with better energy absorption.

### Finite Element Modelling of a Compression Test on AISI 1016 Cylindrical Steel: A Review

Predicting the material flow behaviour of steel is always an important undertaking especially when there is a need to decide on a suitable material required for a particular application. Compression test is normally considered as a standard bulk workability test and a common quality control test, which can be applied to hot forging operations, or cold upset forging. The test is useful when the friction conditions, especially in hot working, require an evaluation. The flow stress data for metals at various temperatures and strain rates could also be predicted. The aim of this study was to conduct a hot compression test on AISI 1016 carbon steel using finite element modelling (FEM) in order to predict the flow stress behaviour of the material including the damage prediction due to shear cracking. Three lubricating conditions namely: Coulomb $$\mu = 0.3 \left( {\text{lubricated}} \right),$$ μ = 0.3 lubricated , shear $$\mu = 0.3$$ μ = 0.3 lubricated and dry $$\mu = 0.7$$ μ = 0.7 were used in the modelling. The results indicate that the largest deformation appears as a shear cross in form of an hourglass in the plastic zone of the specimen at the centre of the cylinder and varies according to the lubricating condition, while the less deformed regions are stagnant as dead-metal zones (DMZ). The highest damaging parameter, though moderate appears at the bulge of the cylinder and this can be the source of shear cracking in the material. It was also observed that there is inhomogeneous deformation inside the workpiece, which could result in substantial damage to the forging process and forging quality respectively. Besides, inhomogeneous deformation could also worsen the finish-forging process.

V. Musonda, E. T. Akinlabi

### Evaluation of Tie Wing Deformation in 0.022 Inch Stainless Steel Orthodontic Bracket—A Finite Element Analysis

Orthodontics is the field of dentistry, which deals with the misalignment (malocclusion) of teeth and its treatment for correcting the improper bite in the jaw. Orthodontic brackets are a component of fixed appliances that are used in orthodontics that aligns and rectifies the misalignment. Archwires are used to control the movement of teeth by giving load on the bracket, which transfers the force to the teeth. Since the nineteenth century, with the development of orthodontics, various models of brackets that varies in shape and size were invented. The response behaviour and the effect on the bracket for the load applied by the archwire varies for different shape and slot size. As a result, the deformation and stress evolved on the bracket varies. Thus, our study aims to find the tie wings deformation in a conventional orthodontic bracket. Archwire is made to rotate with different angles inside the slot of the bracket. In our methodology, the bracket and archwire assembly were modelled, meshed and finite element analysis (FEA) was done on the brackets to evaluate the tie wings deformation for the various angle of twist on the archwire as done in a clinical situation.

Akhil Minu Ajayan, V. Magesh, P. Harikrishnan, D. Kingsly Jeba Singh

### A Finite Element Analysis to Study the Effect of Various Loading Conditions on the Intervertebral Disc in L4–L5 Section of Lumbar Spine

Lower back pain has been one among the difficulties faced in general, occurring in prevalent due to natural intervertebral disc failures in the lumbar spine region. Studies are required to examine natural disc failures due to day to day activities. A model of human lumbar spine section L4-L5 was generated to check for stability of natural disc under various loading conditions using finite element analysis. Computer tomography scan images were compiled together to generate a three-dimensional model of lumbar spine section L4-L5 by segmentation technique. Further, the model was prepared along with the generation of cortical bone, annulus pulposus, nucleus pulpous, vertebral endplates and corresponding ligaments. The material properties for each of the components were incorporated into the model from the literature available and meshed for analysis. The L4–L5 lumbar spine section model created, upon being checked for different motions of spine showed satisfying results yielding normal human motion preservation. Natural disc deformation parameters were observed under different loading conditions for daily activities.

J. Daniel Glad Stephen, M. Prakash, V. K. Nevedha, Manu Pandey

### Numerical Simulation of a Small-Scale Shock Tube Using OpenFOAM®

Shock waves are a phenomenon that can be produced under constrained conditions inside a shock tube. These waves have a wide scope of studies due to their multi-disciplinary applications. Therefore, in the present work, the main focus is to conduct transient numerical simulations of a small-scale shock tube which has been designed and fabricated. Comparison of 1D, 2D, and 3D cases, and grid independence studies have been carried out successfully along with parametric study by variation of driver section pressures. Simulations are conducted using the open-source Computational Continuum Mechanics toolbox, OpenFOAM®. Processing of the simulated data is carried out using Paraview via quantitative and qualitative methods.

Satheesh Kumar Aravind, Anugya Singh, B. T. Kannan

### Contact Stress Analysis on a Functionally Graded Spur Gear Using Finite Element Analysis

Gears are one of the most essential and most significantly used power transmitting parts. Spur gears are more commonly used in practice as it is easy to manufacture and it is simple in design. The failure of gear is mainly attributed to stresses developed in the gears. Contact and bending stresses developed in the gears significantly reduce the lifetime of the gears being used. Materials which are tailored for specific applications can be put under test to minimise the stresses developed and increase the lifetime. Functionally graded materials are advanced materials with spatial gradation in composition to achieve specifically tailored properties. This work attempts to implement functionally graded materials (aluminium-steel, steel-zirconium) in the gears drives. Further, finite element analysis is used to evaluate its contact stresses for various distributive laws (exponential, linear, and power). In addition to that, the contact stress of the functionally graded spur gear is compared to a conventional gear material (EN8 Steel) to evaluate its contact load capacity. The contact stresses were assessed for various torque values. It was found that the change in the distributive laws influenced the contact stresses induced in gear. Also, aluminium-steel showed comparatively less contact stress compared to steel-zirconium and homogeneous steel.

V. Aravind, S. Adharsh, D. Prakash, S. Martin Vinoth, P. Marimuthu

### Finite Element Analysis of Knee Joint with Special Emphasis on Patellar Implant

Patella is supporting part of knee and also guide for quadriceps or patellar tendon. Patellar implant is used for proper functioning of patella after injury. For implant, it is required to cut injured portion of host patella and keep remaining part minimum up to 12–14 mm and overstuffing of 2 mm to prevent patellar fractures. The patellar implant makers provide only 8-mm-thick implant to maintain original patellar thickness which is difficult to achieve especially in patients with host bone thickness less than 20 mm. Hence, there is need to analyze for reduction in thickness of patellar implant from 8 to 6 mm for perfect engagement with adequate residual bone. The critical force analysis on host patella with tendon is carried out for quadriceps force, patellofemoral force, and patellar tendon force using analytical and finite element method. Two cases are considered for the force and stress analysis of patella, and the comparison of various implant thicknesses is discussed.

M. A. Kumbhalkar, D. T. Rangari, R. D. Pawar, R. A. Phadtare, K. R. Raut, A. N. Nagre

### Simulation and Hardware Implementation of Interleaved SEPIC Converter with Valley-Fill Circuit for HBLED System

LED lamps are nowadays preferred for lighting compared to the fluorescent lamps due to its longer lifetime and low power consumption. But the design of driver circuits designed for high brightness (HB) LED demands high power factor, more reliability, high efficiency and precise control. Therefore, to achieve this, a single-stage power factor correction model (PFC) and valley-fill is proposed in this paper. Valley-fill incorporated in SEPIC reduces the strain on output diode and middle capacitor, thus achieving great power factor and competence. Further to moderate the ripple at input and output stages, an interleaving concept is applied to SEPIC with valley-fill circuit. The combination of interleaving and valley-fill circuit leads to reduced voltage ripple, improved power factor and efficiency. A simulation study of the proposed SEPIC converter is carried out by MATLAB/SIMULINK. The performance factors such as source power factor, supply THD, supply distortion factor, supply displacement factor, power loss, output voltage ripple and efficiency are computed, and the results are compared with the classical SEPIC converter without valley-fill circuit. A prototype of an interleaved SEPIC converter is assembled to confirm the simulation results.

B. Lakshmi Praba, R. Seyezhai

### Finite Element Analysis of a Two-Post Rollover Protective Structure of an off-Highway Motor Grader

Rollover protective structure (ROPS) is a critical safety system mounted on off-highway equipments, which serves as a safety structure for an operator survival during rollover accidents. ROPS is classified as single post, two post, four post, and multi-post; selection of this ROPS depends on the type of the application. Commonly used off-highway equipments are dump truck, articulated scrapers, dozers, water sprinklers, excavators, loaders, motor grader, etc.; among these equipments, motor graders were extensively used in off-highway and mining works. It is noticed from the accidents summary reported by the Directorate General of Mine and Safety, India, and Occupational Safety and Health Administration (OSHA), USA, that a significant failure was noticed by the motor grader ROPS structure. Hence, it is necessary to study the failure behavior and strength criteria of rollover protective structure. In the present research work, attempts are made to study the failure behavior and strength of a two-post motor grader (25 tons GVW) ROPS using finite element analysis (FEA) software ANSYS. Further, an interlock section was introduced in the ROPS column to minimize the overall size and to enhance the performance of the ROPS. Later, comparative analysis has been done on this ROPS in terms of maximum deformation, rate of energy absorption, and C.G height. It is evident from the results that proposed ROPS has 30% reduction in overall size, 5% reduction in weight, and enhanced C.G of height. Further, the proposed ROPS meets the performance requirement of existing standards.

V. Kumar, G. Mallesh, K. R. Radhakrishna

### Investigating the Route to Flutter in a Pitch–Plunge Airfoil Subjected to Combined Flow Fluctuations

The dynamics and response a pitch–plunge airfoil with cubic hardening nonlinearity in the pitch degree of freedom are investigated numerically. The aerodynamics is assumed to be linear and modeled using the unsteady aero-dynamical formulation. The flow is fluctuating in both the longitudinal and vertical directions. The fluctuating flow is mathematically modeled as a long time-scale random process. The mean flow speed is used as the bifurcation parameter, and response analysis is carried out by systematically varying the bifurcation parameter. The route to flutter is presented, and the role of noisy flow fluctuations in the same is analyzed by examining the dependency on noise intensity.

Nivedhithaa Santhakumar, Divyangi Singh, Venkatramani Jagadish

### A Computational Study on the Effect of Supercritical CO2 in a Combustor

The ability of supercritical carbon dioxide (sCO2) oxy-combustion power cycles like Allam cycle to capture 99% of the carbon produced in combustion started gaining attraction nowadays. The Allam cycle works at extreme pressure conditions (200–300 bar), and it substantially increases the efficiency. To promote and accelerate the growth and development of combustors for such cycles, a study on kinetic models using sCO2 as diluent has to be conducted by exposing it to extreme operating conditions such as higher pressures (300 bar) and high inlet temperatures (1000 K) along with different levels of CO2 dilution. The paper focuses on identifying the effect of supercritical CO2 in a combustor where the fuel used is methane by analyzing its impact on parameters such as temperature and ignition delay time (IDT) for the CH4–O2–CO2 mixture with variation in CO2 dilution. The software ANSYS Chemkin-Pro is used for the initial simulations where two zero-dimensional models are analyzed with the above said conditions of pressure and temperature for various mixture ratios of CH4–O2–CO2. Saudi Aramco 2.0 mechanism is used for Chemkin simulations. Finally, computational fluid dynamics (CFD) simulation of combustor is done in ANSYS Fluent by importing GRI-Mech 3.0 and the reduced Aramco 2.0 mechanisms and compared the results for different CO2 dilutions.

Vishnumaya Nair, Selvaraj Prabhu

### Design of Shell-and-Tube Heat Exchanger with CFD Analysis

Heat exchanger is a device used to transfer heat between two fluids which are at different temperatures. An attempt is made in this paper. A shell-and-tube heat exchanger (STHE) is modeled by using CATIA V5 R20 software with TEMA standards. Meshing and analysis are done by using Autodesk CFD Simulation commercial software. The STHE is considered for two different fluids of kerosene and crude oil with inlet temperature and inlet velocity of fluids as boundary conditions. The results obtained are contours of velocity magnitude, temperature distribution and pressure drop of the fluid. Then, results are plotted for the temperature distribution, pressure drop and fluid velocity profiles. The simulation results are compared with the analytical results and find good agreement with the analytical results.

B. Jayachandraiah, C. Dinesh Kumar Patel

### Characterization of Rayleigh–Taylor Instability at the Fluid–Fluid Interface

Two fluids of different densities superposed one over the other or accelerated toward each other develop instability at the plane interface between the two fluids. This instability known as Rayleigh–Taylor instability (R-T) plays an integral role in fluid atomization, metal liner electromagnetic implosion, inertial confinement fusion, plasma fusion reactors and deuterium–tritium fusion target laser implosion. In the secondary stages of atomization, R-T instability dictates the quality of spray influencing the performance of engines. The objective of this study is to characterize the interfacial instability at the fluid–fluid interface based on growth rate and the wavenumber of the disturbances generated at the interface. The stability of the fluid–fluid interface under the influence of inertial, surface tensional and rotational forces has been investigated. The test fluids taken for this study include standard fluids, namely water and air, forming interfaces with commercially used fluids, namely nitromethane, ethylene glycol, gasoline and diesel. An attempt has been made to understand the factors contributing to instability of the fluid–fluid interface assumed to be inviscid based on the growth rate and critical wavenumber of the generated disturbances.

Nihal Raj, S. Karthick

### Heat and Mass Transfer Analysis of Al2O3-Water and Cu-Water Nanofluids Over a Stretching Surface with Thermo-diffusion and Diffusion-Thermo Effects Using Artificial Neural Network

The present paper deals with the artificial neural network (ANN) modeling of heat and mass transfer on magnetohydrodynamic (MHD) convective flow of Al2O3-water and Cu-water nanofluids past a stretching sheet through porous media with thermo-diffusion and diffusion-thermo effects. The set of suitable similarity transformations are employed to alter the nonlinear partial differential equations into ordinary differential equations. The solutions of the resulting nonlinear differential equations are solved numerically with the help of Runge–Kutta Fehlberg fourth–fifth order method accompanied by shooting technique, and then, the ANN is applied to them. The multilayer feedforward neural network with backpropagation training algorithm is used for predicting the desired outputs. The influence of various physical parameters on velocity, temperature and concentration profiles is explored and discussed in detail. The friction factors, heat and mass transfer rates are predicted using ANN. The numerical results and the results of the ANN are in good agreement with errors less than 5%. According to the findings of this paper, the ANN approach is reliable and more effective for simulating heat and mass transfer in MHD nanofluid flow over a stretched sheet.

D. Seenivasan, M. Elayarani, M. Shanmugapriya

### Design of Macro-rough Surface and Its Influence on Side Wall Heated Square Enclosure

In the power electronics sector, silicon carbide devices are operational at high junction and case temperatures. Drastic reduction in the size of electronic components including heat sink has been achieved by using silicon carbide rather than silicon. Depending upon the application, the challenges in thermal management can be addressed, preferably passive cooling. If electronic components and its casing have higher operating temperatures, the analysis of natural convection in power electronics is more important. Hence, the present study elucidates the influence of macro-rough surface on natural convection. In this study, a square enclosure with and without macro-roughness have been modelled by maintaining top and bottom walls as adiabatic. The parameters varied are Rayleigh number, number of roughness elements and its thickness. The fluid flow and heat transfer characteristics have been explained with the help of velocity and temperature contours. From the results obtained, we have concluded that the increase in roughness elements and its thickness have reduced convection near the roughness elements.

Ashwin Mahendra, Rajendran Senthil kumar

### Performance Enhancement of a Savonius Vertical Axis Wind Turbine with Bio-Inspired Design Modifications

One of the prime commodities in modern civilization is energy. The amount of energy consumption has become the indicator for the standard of living and the degree of industrialization. People use fossil fuels to meet nearly all of their energy needs, such as powering vehicles, producing electricity for light and heat and running factories, thus greatly exhausting the fossil fuel reserves along with polluting the environment with greenhouse gases. Renewable energy sources are viable alternatives, and among the various types of renewable energy sources available, wind energy is the sector which has a lot of untapped potential. Our objective is to improve the efficiency of a Savonius-type vertical-axis wind turbine (VAWT) which currently has the least efficiency among existing wind turbine designs. Savonius turbines have a very compact structure and can run at low wind speeds which are desirable characteristics for commercial-scale power production. This research paper focuses on improving the efficiency of Savonius wind turbine. Since Savonius-type wind turbines are drag-based wind turbines, we need to reduce the impulsive force acting on the negative face in order to increase the drag difference between the positive and negative side of the rotor blades thereby improving the efficiency of the turbine. Our proposition for attaining higher efficiency is by incorporating the concept of dimples (inspired from golf ball) on the negative side of the rotor blade and tubercles (inspired from whales) on the leading edge of the rotor blade. Dimples reduce the amount of wake region in the case of golf ball by increasing turbulence which is one of the desirable characteristics in the case of Savonius wind turbine. Tubercles help in reducing the wake region behind the rotor blades by increasing the turbulence of air near the surface of the rotor thereby improving the efficiency of the turbine.

S. M. Hasan Fayaz, Uditya Tyagi, Apurva Jain, Nishant Mishra

### Experimental Investigation of Heat Treatment Processes on Dissimilar IS2602-EN9 MIG Welded Joint

The present investigation, influence of different heat treatment processes which will yield better tensile strength and microstructures of 8-mm-thick plates metal inert gas welded IS2062-EN9 joint. Mechanical properties of the joint increased with annealing heat treatment processes, higher grain size was measured at welded zone, and it decreased. It is found that the joint fabricated at a low heat input condition showing excellent mechanical and metallurgical properties. After annealing heat treatment process, tensile strength improved around 14.52%, the pearlite phase increased from 36.75 to 47.15%, and ferrite phase has decreased from 59.36 to 50.61% and other decreased from 3.88 to 2.24%. The tensile strength is improved due to grain size that was observed to be 7.5 before heat treatment and 9 after annealing heat treatment, and ferrite phase is transformed into pearlite phase.

Mallapuram Bala Chennaiah, Podaralla Nanda Kumar, Karanam Prahlada Rao

### Feasibility of Al2O3/Water Nanofluid in a Compact Loop Heat Pipe

Effect of low volume concentration of water-based aluminium oxide (Al2O3) nanofluids on the thermal performance and entropy generation of a compact loop heat pipe (CLHP) with the flat square evaporator of dimensions (34 mm × 34 mm × 19 mm) is experimentally investigated. The heat input and volume concentration are varied from 30 W to 500 W and 0.03%, 0.09% and 0.12%, respectively. The effects of performance parameters such as heat supplied and nanoparticle concentration on the entropy generation, thermal resistance, evaporator and condenser heat transfer coefficients (HTC) are analysed. Results showed that the formation of thin porous deposition on the wick and wall plays a key role in the enhancement of heat transfer of the CLHP. The heat transfer coefficient was found to be enhanced by 24.42% in the evaporator, and the thermal resistance was reduced by about 21.29%. The entropy generation is also reduced by 12.36% when Al2O3 nanofluid is used as the working fluid. Adding a little quantity of Al2O3 nanoparticles enhanced the operating range of CLHP by 12% when compared with that of the base fluid.

Emerald Ninolin Stephen, Lazarus Godson Asirvatham, Kandasamy Ramachandran, Arulanatham Brusly Solomon, Pitchaimuthu RamKumar

### Analysis of Externally Pressurized Thrust Bearing with Inclination Angle Using Yield Stress Fluids

In this investigation, the effects of the non-Newtonian characteristics and angle of inclined plane (ɸ) of the externally pressurized bearing lubricated with yield stress fluid is studied. We have obtained mathematical formulation for varying film thickness. Applying appropriate boundary conditions and numerical procedure, the governing equations are solved iteratively. There is a formation of an unyielding core in the flow region for yield stress fluids, and the shape and size of this core have been calculated numerically. Further, the effects of the angle of inclined plane (ɸ) and non-Newtonian characteristic on pressure distribution and load capacity are discussed.

G. Alexander Raymand, I. Jayakaran Amalraj

### Numerical Investigation of Bingham Fluid Flow in the Entrance Region of Rotating Annuli

The study of the entrance region flow is, nowaday, assuming considerable technical importance due to its immediate applications in various designs of chemical and biomedical equipments in which the flows of non-Newtonian fluids are encountered. The flow characteristic of non-Newtonian fluid that is independent of time, and which obeys Bingham’s stress–strain relations, has been investigated at the entrance region of the annular space between two rotating coaxial cylinders. This analysis has been carried out for both the cases when each rotates with different speed in the same direction and as well as in the opposite direction with constant angular velocity. Discussions have been presented for a steady, laminar, isothermal flow condition of the Bingham fluid. The continuity and momentum equations are solved iteratively with finite difference method by using the Prandtl’s boundary layer assumptions. The velocity components and pressure distributions have been obtained numerically for various values of Bingham number and aspect ratio.

S. Mullai Venthan, I. Jayakaran Amalraj

### Nanofluids in Improving Heat Transfer Characteristics of Shell and Tube Heat Exchanger

The thermal performances of shell and tube heat exchanger [STHE] are investigated using Ag–W and CuO–W nanofluids with suspended particle volume concentrations between 0.02% and 0.06% of Ag and CuO. The comparison is made with reference to base fluid. The result revealed that thermal conductivity of the nanofluids, which is dependent on the particle volume concentration, influenced the heat transfer ability. Highest overall as well as convective heat transfer coefficients and highest actual heat transfer are obtained for 0.06% volume concentration CuO–W nanofluid. An improvement of about 19% in heat transfer coefficient is recorded for 0.06 vol% of CuO–W nanofluids with respect to water. Also, the overall heat transfer coefficient enhanced between 64 and 79% for 0.06 vol% of CuO–W nanofluids. However, in the tube-side, pressure drop increases with increase in nanofluid volume concentrations. Actual heat transfer improved by 39–56% with reference to water. It can be concluded that better heat transfer characteristic for the STHE is obtained by keeping the shell-side mass flow as fixed and varying the tube-side mass flow rates.

S. Seralathan, R. Vijay, S. Aravind, S. Sivakumar, G. Devaraj, V. Hariram, P. S. Raghavan, T. Micha Premkumar

### Design and Numerical Analysis of Gearless Transmission Used in Small Wind Turbine

The main function of the gearless transmission system is to transmit power between two shafts through the sliding links that develop revolute pair between the hubs of two shaft. Normally the output link is bent at any angle between 0 and 180°. Moreover, as the hub in the driving shaft rotates, holes in this hub rotate, which in turn pushes the links and it drive the output. Moreover, torque developed in the small wind turbine is small so it is effectively used in this low torque applications. The objective of this project is to analysis gearless drive that is being simple and transmitting power preciously at almost right angle without any bevel gears. This mechanism is completely analysis using Ansys© software to lookout the elbow rod the hub under different working condition. Numerical analysis is made by rotating the mechanism at different rpm, viz. 0–150 rpm. Reaction forces and reaction moment are analyzed for 5 s simulation and compared with allowable stress. In this investigation, the effect of number of links and size of link is studied to find the permissible operating speed of mechanism. The major outcome of this work is to get the permissible limit of the stress, strain, speed, torque transmitting capacity of this mechanism as it is very much attracting the research community in replacing the conventional bevel gears. It is observed that the optimum number of link for better transmission is 8 and its diameter is 8 mm, and optimum speed of the mechanism is 100 rpm, so this mechanism is suitable for the small wind turbine.

Micha T. Premkumar, V. Hariram, S. Seralathan, Pinku Kumar, Godwin John

### Experimental Investigation of Unsteady State Heat Transfer Behaviour of Nanofluid

This paper provides the method for preparation of nanofluids and measuring thermal properties of nanofluids by various methods. In this paper, we have focused on effect of variation of temperature, particle size and volume fraction of nanofluid on properties of nanofluid such as density, viscosity, thermal conductivity and heat transfer coefficient. We have made comparison between CuO, ZnO and SiO2 nanoparticles with particle size 30–50 nm and 50–70 nm and with three volume fractions 0.5, 1 and 1.5%. The heat transfer coefficient (h) of all nanofluids is determined from unsteady state heat transfer apparatus. The results indicate that the thermal conductivity and h of nanofluid enhance with increase in %vol. fraction and decrease in particle size. CuO–DI water nanofluid with 1.5% volume fraction and 30–50 nm particle size has higher heat transfer coefficient, and thermal conductivity is enhanced by 59.59% than de-ionized water. Hence, CuO–DI water nanofluid (1.5% vol. fraction and 30–50 nm particle size) reaches steady state faster than other nanofluids.

Yogiraj Bhumkar, A. R. Acharya, A. T. Pise

### Switched Staircase-Type Multilevel Inverter Structure with Reduced Number of Switches

Modern research has been involved in developing distinctive multilevel inverter (MLI) circuits. The main aim of this paper is to propose a new MLI topology based on the series–parallel connection of several dc sources with reduced number of switching components. The basic structure of the proposed topology generates only positive voltage levels, and thus, it requires an additional H-bridge unit to create both negative and zero voltage levels. The generalized structure for the proposed MLI topology has also been presented in this paper. Additionally, different strategies are suggested to determine the magnitudes of the dc sources in order to produce more output steps. Compared with the conventional and other recently presented improved topologies, the proposed inverter reduces the number of switches, dc sources, and the maximum voltage blocked by the switches. At last, simulation results for 7-level symmetrical and 17-level asymmetrical inverters are presented in order to confirm the performance of the proposed inverter.

V. Thiyagarajan

### Hydro Pneumatic Parking Brake Actuation System for Motor Grader Application

Motor graders are used in many applications in the Mining and Construction fields. In India, grader models running on road need to meet the Central Motor Vehicles Rules (CMVR 1989) [1], i.e. RTO regulations formulated by the Ministry of Road Transport and Highways (MoRTH) and in the mines has to meet the DGMS regulations. Hydraulic or air-operated brake system is installed in graders for slow down and stop. Air brake system is preferred due to its simple construction, low cost and easy serviceability. Parking brake is used to hold the equipment on slopes in stationary conditions and for parking. As per the vehicle safety standards, parking brakes are designed to be fail safe. To meet this, spring applied, air/hydraulic release type parking brakes are used. Motor grader having 12 ft work blade length uses the air system for regular service brakes and internally expandable shoe type parking brake that is actuated by mechanical ratchet pinion mechanism is taken up for study. New disc type spring applied hydraulically released parking brake is designed to improve the holding performance. Need arise to invent a new actuation system as the main service brakes use air-operated brakes and hydraulic power required for parking brake application. The new hydro pneumatic parking brake actuation system has been designed and tested. The practical field tests reveal that new parking brake system reduces operator fatigue, builds up more confidence in operator and ensures safety of higher order.

K. Rajasekar, S. Karthikeyan, V. Kumar, H. S. Satish Chandra

### Design and Analysis of Feature Primitive Scaffold Manufactured Using 3D-Printer—Fused Deposition Modelling (FDM)

The scaffold guided tissue is a branch of tissue regenerative medicine approach. The scaffold acts as a temporary structure for bone growth and provides a better environment and architecture for the regeneration of bone. In this work, five different features were defined in parametric form using CATIA. The relationship between geometric parameters and porosity, surface area-to-volume ratio was developed with constant inter-pore distance. The developed relationship of scaffolds was evaluated by designing of 40% porosity. All these scaffolds were manufactured with biocompatible Poly Lactic Acid (PLA) material using Ultimaker3–FDM system. The mechanical properties of a scaffold were evaluated by the compression test, and finite element analysis was performed using ANSYS software. The experimental and finite element analysis (FEA) results were compared to understand the microscale level modelling and variability of mechanical properties of scaffold manufacturing with 3D printing technology. In this study, we have obtained experimental effective elastic modulus (or) Young’s modulus is 858.69 MPa and compressive strength (27.693 MPa) of a scaffold (P1), maximum porosity was (38.06%) for scaffold (T1). In FEA, the maximum effective Young’s Modulus is 1086 MPa for scaffold (P1), maximum stress is 29.54 MPa for scaffold (C1) and maximum strain is 0.331 for scaffold (T1).

P. Vishnurajan, S. Karuppudaiyan, D. KingslyJeba Singh

### Design and Development of Modular Parallel XY Manipulator

Flexure mechanism provides precise and repeated motion over a small range. Many monolithic designs have been discussed in the literature however they are costly to manufacture and give no flexibility for change in the parameter. This paper represents flexure micromotion stages with modular design. Compliance matrix method has been used for designing the flexure mechanism. Nonlinear 2-DOF model is used to characterize the stiffness of XY stage, maximum stress-induced. Proposed XY motion stage has a travel range of ±3.2 mm2 with 0.12 mm parasitic error. Dynamic analysis is performed to determine modal frequency of the stage. Maximum error estimated in analytical and FEA model is 26.38%. Linear and nonlinear analytical results are compared with FEA and are in agreement.

Santosh R. Thorat, R. B. Patil

### Design of hyper-redundant In-Vivo Robot: A Review

Conventional clinical process involves a large incision in the stomach to perform the surgery or biopsy to collect the infected tissue from the abdominal cavity. However, the process requires expertise and often leads to a surgeon’s tremor and patient’s discomfort. The inclusion of a robot to assist in biopsy and surgery is a boon for both surgeon and patient as it reduces the surgeon’s error in pinpointing the infected area and also results in a minimum incision requirement to do so, which is called as Minimally Invasive Surgery (MIS). In some cases, the entire robot is placed inside to do the task and called an in vivo robot. The current study focuses on the various design strategies adopted by researchers around the globe and the outcomes. This state of the art will be useful to enhance the design strategies further to refine the most cutting-edge research outcomes further.

Sushil Dev Rout, Mihir Kumar Sutar, Sarojrani Pattnaik

### Effect of Insertion Force for Successful Penetration of a Conical Shaped Microneedle into the Skin

Microneedles and microneedle-related technologies are the present trends in medical science which are voraciously being investigated by the research community towards various therapeutic and medical diagnostic applications, since they are treated and also to be considered as painless methodology of administering vaccines. Apart from that these microneedles clearly aids in mitigating the potential risk of infections and ailments related when needle transfusions when the medicine is transmitted into the body. Microneedles have gained much upfront and considered to be a novel way for administering drugs and vaccines through transdermal drug delivery. This particular area primarily mends upon the design and analysis of silicon and stainless steel based hollow conical microneedles for transdermal drug delivery (TDD). The effect of axial and transverse load on a microneedle has been investigated along with the mechanical properties. The analysis predicts that the resultant stresses due to applied bending and axial loads are in the safe & comfort desired range. The primary work was focused on the conical-shaped hollow needles of micron-sized dimensions. In this paper simulation studies are carried out on the stress analysis along with displacement parameters.

Gera Aswani Kumar, Burra Rajesh Kumar, Vankara Jyothi, Sowmya Injeti

### Lumbar Discography: Study of Biomechanical Changes in the L1-L2 Intervertebral Disc of the Human Lumbar Spine Using Finite Element Methods

Lumbar discography is often used as a pain recognition technique for evaluating patients who have otherwise not responded well to non-surgical methods (radiology). While the injection technique provides unique information about the disc which is not obtainable through other methods, the procedure is suspected to cause prolonged damage to the disc. A study concentrating on equivalent stress in different regions of the disc shall provide useful insight on the prolonged effects of the lumbar discography procedure. A computational model of the functional spinal unit that accurately mimics its material properties and motion is required to simulate the medical procedure performed on the intervertebral disc. This study uses a hybrid finite element model of the L1-L2 motion segment of the lumbar spine of a 35-year-old male subject. In order to mimic spinal motion during flexion and extension, all supporting ligaments were added to the finite element model. Hyperelastic material properties were altered to simulate the discography procedure and equivalent von Misses stress values across the Annulus Fibrosus were recorded. A considerable increase in the equivalent stress across the annulus was observed in the punctured controls. Thus, the injection technique alters the stress concentrations across the disc and can have prolonged degenerative effects on the IVD.

S. Balamurugan, P. Susai Manickam, Sachit Chawla

### C4–C5 Segment Finite Element Model Development and Investigation of Intervertebral Disc Behaviour

Clinical problems of the human cervical spine continue to be widespread in our society. In the past few decades, many experimental and simulation techniques were adopted to study the motion of the cervical spine. The functional spine unit is made of vertebrae, end plates, intervertebral disc and ligaments. To understand the biomechanical behaviour of cervical spine a detailed finite element model is needed. The focus of the study is to develop the cervical spine from (C4–C5) finite element model with accurate dimensions and representation of the material properties. A three-dimensional finite element (FE) model of cervical spine segment (C4–C5) was developed using computed tomography CT scan and applied to study the stresses distribution of the intervertebral discs under quasi-static loading conditions. A pure moment loading of 1.0 Nm was applied to study the physiological motion. The model accuracy was validated by comparing the results with the previously published experimental and numerical results for various physiological motions. Several movements were analysed: flexion, extension, lateral bending and axial rotation. By using elastic and hyperelastic model behaviour of the intervertebral disc was accurately simulated. The results obtained by the elastic and the hyperelastic models showed good agreement with experimental and numerical data. The current model which reflects the behaviour of human cervical spine can be effectively used to study further biomechanics and traumatic studies.

P. Susai Manickam

### Simulation and Analysis of Integrated SEPIC-Flyback AC-DC PFC Converter for LED Applications

Light Emitting Diode (LED) inherently acts as a diode which allows the current in one direction and this can be achieved by AC-DC converter. It is essential to have sinusoidal input current wave shape and constant load current to drive the LED without any flicker. Integration of Single Ended Primary Inductor Converter (SEPIC) and Flyback converter act as an LED drive. Both these converters are operated in discontinuous conduction mode for supplying LED to achieve the unity power factor. It is compared with conventional SEPIC and Flyback topology. Analysis and simulation of 100 W LED module from 100 VP-P/50 Hz ac supply are analyzed and their results are presented using MATLAB-Simulink.

Sridhar Makkapati, Seyezhai Ramalingam

### Simulation Study of Shading Effects in PV Array

The PV panels are interconnected in SP configuration in order to achieve a higher voltage. The SP configuration of PV string may undergo both objective and subjective partial shading situations which reduces the generated maximum output power. Thus, the research work carried out the analysis of PV array rated 1500 W for different shading patterns like row-wise and column-wise partial shading. The behavior of solar array is also studied under different irradiation levels and different degrees of shading. The behavior of PV string characteristics for with and without bypass diode under different shading scenarios has also been analyzed using MATLAB/SIMULINK. The performance parameter of a solar array such as power loss, fill factor and a maximum power of the PV string is evaluated and compared. From the analysis, it is inferred that the generated output power gets deteriorated for low irradiation level and low degree of shading. The results are verified.

S. Harika, R. Seyezhai, A. Jawahar

### Speech Recognition Using Neural Network for Mobile Robot Navigation

Automatic speech recognition (ASR) has gained a lot of popularity in the mobile robotics, where the commands could be provided to the robot wirelessly to maneuver. A navigation system combined with ASR is a complex system to carry out, because the system has difficulty in recognizing the voice commands when the environment involved already has disturbances like road noise, air conditioner, music, and passengers. The objective of this research is to operate a mobile robot with a single-arm manipulator, where the robot can perceive the speech and it can react to the individual speech commands provided by the operator swiftly and precisely. In order to recognize the speech, mel-frequency cepstral coefficient (MFCC) speech recognition algorithm is chosen and implemented in MATLAB. Various training and testing have been done in MFCC algorithm where it has to carry out the real-time processing of speech data and respond to it. Based on both the training and testing the voice commands collected from the five test subjects both male and female, the speech recognition system achieved 89% efficiency for the test database.

Prashant Patel, Arockia Selvakumar Arockia Doss, L. PavanKalyan, Parag J. Tarwadi

### Range Sensor-Based Obstacle Avoidance of a Hyper-Redundant Robot

In recent times, the development of the bio-mimicking is increasing in the robotics field. This paper discusses the design of the hyper-redundant robot and manoeuvring in the environment. The robot works on the Coulomb’s friction law where the friction between robot and surface helps to move the robot. The robot models are fabricated by 3D printing. The robot uses passive wheels for its locomotion. A range sensor is used to detect the obstacles in the environment. A Bluetooth module is utilized for the wireless control of the robot. This paper describes the design of the hyper-redundant robot to avoid the obstacles in the environment using a range sensor and the robot follows the serpentine motion for the locomotion.

G. Mohammed Nawaz, N. Karthikeyan

### Literature Survey on Four-Legged Robots

Over the last two decades, the research and development of legged locomotion robots has grown steadily. Legged systems present major advantages when compared with ‘traditional’ vehicles, because they allow locomotion in inaccessible terrain to vehicles with wheels and tracks. However, the robustness of legged robots, and especially their energy consumption, among other aspects, still lag behind mechanisms that use wheels and tracks. Legs are not new to humans or animals but building legs for a robot is a complex process. The normally noticed and ignored fact is how a baby learns to walk and the sheer learning curve involved. If we, the intelligent humans take years to learn to walk, imagine creating legs for a robot and teaching it how to walk. Although there is an extensive research going on in the field of legged robots, researchers are still in developing stage to construct a legged robot which can replicate human walk, or for that matter any animals. And a few of their current area of research are in maintaining dynamic stability of the robot, reflex of the robot to sudden impacts and also interaction with the terrain to produce suitable gait. This paper gives a brief description on a few of the existing legged robots on various aspects of a robot and on how each one of them affects the dynamics of the robot. This paper enhances a space for future research on understanding the various aspects of a legged bot design.

G. Satheesh Kumar, S. Aravind, R. Subramanian, Shashank Kannan Bharadwaj, Ronak R. Muthuraman, R. Steve Mitchell, Aditya Bucha, M. Sriram, K. J. Shri Hari, Nikhil Jerome Robin

### In-Pipe Robot Mechanisms—State-of-the-Art Review

In-pipe robots are a class of robots that have been extensively studied for a very long time and many interesting solutions have been proposed and used in practical scenarios. There are many parameters and functional features that define the characteristics of these robots. An extensive review of the mechanisms that allows locomotion to the in-pipe robots is performed in this paper. A broader classification that allows more clarity on these robots for choosing them based on their capacities is provided. The designs brought out so far have limited itself to one type of scenario where there is no need for the robots to work in coordination. This perspective is different from the other review papers in that sense and is needed for the researchers to identify new design directions for improvising the performance of their robots. A new design perspective for in-pipe robots for swarm applications is also presented toward the end.

G. Satheesh Kumar, D. Arun

### Design and Thermal Performance Analysis on Solar Still

Economically feasible and eco-friendly water treating technologies are most expected in Asia and Africa which lead to an increase in usage of renewable energy. Hence, solar stills are the best choice to resolve the issue related to water scarcity. Due to the low productivity of solar stills, continuous research is being performed considering different parameter changes to optimize its production. Research had been carried out by altering and optimizing the condensing surface of solar still for performance improvement. In this research, the modification of condensing surface is done by multiple hemispherical slopes. The flow pattern has been analysed inside the solar still before and after modification and the changes in performance have been compared with single slope solar still and presented for better understanding.

Shaik Subhani, Rajendran Senthil Kumar

### The Use of Hydrocarbon Refrigerants in Combating Ozone Depletion and Global Warming: A Review

Vapour compression systems are associated with high energy demand and contribute to ozone depletion and global warming due to halogenated refrigerants used in them which are unfriendly to the environment. Hydrocarbon refrigerants have been proposed as a substitute to halogenated refrigerants due to their zero ozone depletion potentials, very low global warming potentials, and lower energy demand for effective operations. In this review, the terms ozone depletion and global warming are explained and the causes. Also, the use of hydrocarbon refrigerants as an ideal solution to energy security and environmental challenges accompanied by vapour compression systems are discussed. Lastly, this paper revealed that hydrocarbon refrigerants are long term replacement for halogenated refrigerants in a vapour compression system.

T. O. Babarinde, S. A. Akinlabi, D. M. Madyira

### Experimental Study of Performance of R600a/CNT-Lubricant in Domestic Refrigerator System

Energy consumption and environmental problems have been the major consideration for comfort systems manufacturers. This research work investigated a varied mass charge of R600a, an eco-friendly refrigerant with a low concentration of 0.4 and 0.6 g/L of CNT nanolubricant concentration in a domestic vapor compression refrigerating system working with pure mineral oil as the base lubricant. The experimental test performance of the system was studied considering pull-down time, COP, power consumption, and cooling capacity. The result showed that CNT nanolubricant had lower evaporator air temperature with higher COP and cooling capacity with a reduction in power consumption compared to R600a in the base lubricant in the system.

T. O. Babarinde, S. A. Akinlabi, D. M. Madyira

### Assessing the Predicting Capability of RSM and ANN on Transesterification Process for Yielding Biodiesel from Vitis vinifera Seed Oil

In this present investigation, the process parameters to obtain maximum fatty acid methyl ester yield from Vitis vinifera seed bio-oil by transesterification were explored using the central composite design with variable input parameters like catalyst concentration (0.5–1.5% of KOH), reaction duration (30–60 min), and molar ratio (3:1–7:1). Response surface methodology (RSM) and artificial neural network (ANN) were employed to predict the optimized biodiesel yield and model the transesterification process. The experimental outputs were simulated using a quadratic model generated by RSM. The maximum biodiesel yield parameters were determined by RSM, and it was found to be 6.4246:1 molar ratio, 66.8205 min reaction time, and 1.1719% of catalyst concentration. The transesterification process performed with this experimental combination resulted in methyl ester yield of around 97.53% which correlated well with the yield predicted by RSM. The statistical analysis was carried out to determine the model validity, accuracy, and predictive capability of both ANN and RSM models. The biodiesel obtained by this process was subjected to analysis for estimating the physiochemical properties like cetane number, calorific value, density, acid value, flash and fire point, and kinematic viscosity, and it was found to be within ASTM limits.

V. Hariram, A. Bose, S. Seralathan, J. Godwin John, T. Micha Premkumar

### Waste Heat Recovery (WHR) of Diesel Engine Using Closed-Loop Pulsating Heat Pipe

In internal combustion engine, around 25–40% of energy is expelled through the exhaust gases into environment which causes pollution. So this energy should be recovered for other applications. This present work represents the study of the pulsating heat pipe (PHP) technique used for heating the air with the help of recovered heat from exhaust of the engine. The CLPHP is most effective, promising heat transfer device than the others, which uses the pulsating or oscillating actions of the working fluid for transferring heat. The performance of CLPHP basically depends on different parameters like filling ratio (F.R), internal diameter of the tube(Di), cross section area of tube (Ac), heat input(Qin), angle of inclination (θ), no of turns (N), working fluid, length of tube in evaporator and condenser section, etc. In this work, eight-loop PHP is made of copper material having ID = 3.2512 mm and OD = 4.7752 mm with water as working fluid. The experimental investigation is performed for different filling ratios (50, 60 and 70%) and at various heat inputs (715.98, 861.48, 935.41, 1004.96 and 1070.5 W) by varying the loads on engine. The result shows that for 50% filling ratio, overall thermal resistance is less and heat transfer coefficient value is more as compared to other filling ratios.

Saurabh B. Dhone, A. T. Pise

### An Experimental Investigation of Heat Transfer in Heat Exchangers Using Al2O3 Nanofluid

Heat is the term distinct as the amount of energy transferred by the virtue of the temperature difference. The heat flows from the region of maximum temperature to minimum temperature by the different methods of heat conveyed. This paper focuses on the study of heat transfer in the heat exchanger which is a device used for transfer of thermal energy and consists of two or additional fluids or between surface of fluid and solid to solid particulates and a fluid at different temperature, thermal constant with and without outside heat and work communications. The parameters of heat transfer are analyzed in different types of heat exchangers. This examination explores the warmth move and the weight drop of cone helically curled cylinder heat exchanger utilizing Al2O3/water nanofluids. The Al2O3/water nanofluids at 0.2, 0.4, and 0.6% molecule volume fixations were set up with the expansion of surfactant by utilizing the two advance strategies. The experimental study of heat transfer in various heat exchangers is discussed.

S. Bhuvaneswari, G. Elatharasan

### Numerical Study of Heat Transfer and Pressure Drop in a Helically Coiled Tubes

The pressure drop and heat transfer are increased due to the secondary flows caused by the centrifugal forces in a fluid through the curved pipes. The heat transfer rate in a helically coil tubes is higher than that of the straight tubes. Due to its compact structure, it has its wide application in industries. This chapter reviews on the of heat transfer flow rates and pressure drop individuality using the parameters such as Dean number, Reynolds number, Nusselt number, friction factor, and correlation. Based on the data obtained experimentally from the literature, computation of heat transfer and pressure fall is obtained by the mathematical equations. These parameters are analyzed and tabulated for all the flows in the helical coil tube. The heat transfer results have demonstrated that when utilizing an Al2O3, an expansion in warmth move rate can be acquired when contrasted with heat transfer results got utilizing straight heat transfer segments. It has reasoned that the expanded explicit heat of the Al2O3 just as the liquid elements in helical loop channels are the primary supporters of the expanded heat move.

S. Bhuvaneswari, G. Elatharasan

### Comparative Study on the Mechanical Performance of Solid Lubricants Over Peek Polymer

Polyetheretherketone (PEEK) and its composites have an extended range of applications and are continuously replacing metals in aerospace, automobile, and mechanical industries for structural and tribological applications due to its robustness, good mechanical and chemical resistance properties. The mechanical properties of virgin PEEK, PEEK reinforced with 10% Polytetrafluoroethylene (PTFE) and PEEK reinforced with 10% hexagonal Boron Nitride (h-BN) are compared and analyzed in this study. The composites were fabricated through the twin-screw extrusion method and were then characterized by EDAX analysis. The static mechanical properties such as compressive, flexural and hardness of all the specimens were tested as per ASTM standards, and it was identified that the virgin PEEK material had better mechanical properties in comparison to materials with solid lubricants. Also, the addition of h-BN to PEEK had a more drastic reduction in mechanical strength compared to the addition of PTFE to PEEK. It was seen that by adding the solid lubricants, the mechanical properties of virgin PEEK material deteriorated.

N. Venkatesh, P. K. Dinesh Kumar

### ZrB2 Influences on the Dry Sliding Wear Resistance of AA7075 Alloy

This article presents the influence of ZrB2 particles on the mechanical and wear behavior of AA7075 composites. Variations in AA7075 reinforced with ZrB2 particles varied in the range of 5–15 wt% and fabricated using of the two-step stir casting technique. Fabricated composites were subjected to T6 heat-treated and analyzed microstructure, hardness, impact, tensile strength and dry sliding wear behavior. Tribo test was conducted with varying applied pressure (0.39–1.59 MPa), sliding velocities of (0.8–2.0 m/s), and a sliding distance of 3.0 km. The results revealed the distribution of particles in the matrix materials. ZrB2 increased the hardness of the composites from 98 to 128 Vickers hardness and reduced the impact strength up to 44%. The addition of 15 wt% of ZrB2 particles increased the tensile strength of AA7075 alloy by 242 MPa. Wear resistance of the composites increased with increasing wt% of ZrB2 particles. Wear mechanism of the worn surface was studied through use of a scanning electron microscope (SEM) and revealed the formation of an oxide layer on the worn surface reducing the wear rate of the composite. At a low applied pressure and sliding velocity, there was the formation of a plastic deformation groove, whereas a high applied pressure and sliding velocity breakage of tribolayer resulted in severe deformation.

P. Loganathan, A. Gnanavelbabu, K. Rajkumar, S. Ayyanar

### Investigation on Wear Properties of Nickel-Coated Al2O3P-Reinforced AA-7075 Metal Matrix Composites Using Grey Relational Analysis

The development of hard reinforcements in MMCs became an important area of research in materials engineering. Metallic coatings on reinforced particles can improve wettability because it plays a key role in aluminium-based metal matrix composites. Nickel plating by electroless method having found to be an efficient method and widely accepted in various engineering domains such as aerospace, automobile, chemical and electrical industries. In this study, 20 micrometer-sized (average) alumina (Al2O3) particles are coated by nickel using electroless deposition technique. Wear specimens are prepared as per ASTM-G99 standards, using coated and uncoated reinforcements of 3, 6 and 9% weight fractions into 7075 aluminium alloy by standard stir casting route. Wear test was conducted by utilizing the test parameters, viz. track diameter, speed and load based on L18 Taguchi orthogonal array, on pin-on-disc machine, and the influencing parameters of responses were optimized using grey relational analysis. Weary surfaces were analysed using scanned electron microscopy. The specimen with 9% coated reinforced composite at 80 mm track diameter, 9.81 N and 1000 rpm showed improved resistance to wear.

D. Vijay Praveen, D. Ranga Raju, M. V. Jagannadha Raju

### Optimizing the Tribological Properties of UHMWPE Nanocomposites—An Artificial Intelligence based approach

The longevity of the hip implants has been a major issue in recent times due to inadequate material used for implants. Since the metal on polymer implants has issues such as tissue degeneration and osteolysis, the focus of this study is to improve the tribological properties of ultra-high molecular-weight polyethylene (UHMWPE) which has been in use on acetabular cup of hip implants by considering multiple nanoparticles like carbon fibre, carbon nanotubes and graphene as reinforcements. It is extremely difficult and time-consuming through numerous experimental trials to arrive at the optimum material composition of nanoparticles. Therefore, an effort has been made on developing a new polymer nanocomposite by utilizing the artificial intelligence (AI)-based design which includes the techniques, viz. artificial neural network (ANN) and genetic algorithm (GA). The input parameters like weight fraction and the geometry of the different nanoparticles related to the tribological properties were collected from various published literatures, and modelling was done through ANN for the output parameters, viz. coefficient of friction and specific wear rate. Best ANN predictive model was chosen individually for each output parameters on iterating the different hidden nodes. The fundamental correlation between the input and output parameters was investigated through sensitivity analysis. Optimization studies were performed using genetic algorithm (GA) with the best-chosen ANN model as an input to get optimum input variables. Thus, the AI-based approach of designing the UHMWPE nanocomposites shows an enhancement on the tribological properties that pave a way for further experimental trials.

A. Vinoth, K. N. Nirmal, Rohit Khedar, Shubhabrata Datta

### Friction and Wear Study of Laser Surface Textured Ti-6Al-4V Against Cast Iron and Stainless Steel Using Pin-on-Disc Tribometer

The reduction in the friction plays a vital role in improving the efficiency of the working machinery. The wear is the direct effect of friction which reduces the lifetime of the machine components. The modification of the surface of the materials can considerably reduce the wear and friction and thus improving the efficiency and increasing the lifetime of the machine components. The surface modification techniques such as abrasive jet machining, ECM, etching and LST are being used to alter the surface properties. This paper presents the laser surface texturing on titanium alloy, cast iron and stainless steel and testing of frictional properties such as friction and wear of titanium pins against cast iron and stainless steel discs. The texturing patterns are designed and laser ablation method is used to texture the surfaces of the pins and the discs. Since the friction is directly proportional to the contact area, the reduction in the surface contact area of the interacting surfaces is obtained through LST which plays a vital role in the reduction of friction wear. The textured patterns on the surface of the materials also act as a reservoir for the debris particles to get entrapped in them and reduce the three-body abrasion. The textured pins are tested against the textured discs using pin-on-disc tribometer. The friction and wear characteristics of the pin and the disc are determined and are compared against the untextured disc and pins. The experimental analysis of the textured surfaces established to reduce the friction and wear characteristic behaviour.

N. Sankara Manikandan, M. Prem Ananth, L. Poovazhagan, B. Sudarsan, A. Vishnuvarthan

### Tribological Study on Sliding Contact Between Laser Surface Textured Titanium and Aluminium Alloy Under Lubrication

The friction plays a major role whenever two surfaces come into contact. The friction is a major factor which affects the efficiency of a working component. The life of the component depends on the wear it undergoes during working. This wear is directly related to the friction that is produced between the surfaces. It is impossible to completely avoid friction. But it is possible to reduce the friction between the contact surfaces by various methods. One of the most promising methods in recent days is the laser surface texturing. There are various developments currently being done in the LST. It is done by altering the various parameters of the textures. Some of the parameters include the pattern, depth, diameter, pitch and so on. In our tribological study, a pin-on-disc tribometer is used to determine the friction and the wear between the components made of Ti-6Al-4V and AA7075 alloys under liquid lubrication condition. For improving the tribological characteristics of the contacting pairs, laser surface texturing is performed on both pin and disc surfaces. The laser surface texturing concept is implemented to create micro-dimples on the contact surface which the dimples act as a reservoir for the lubricant enhancing lubrication to reduce the coefficient of friction, the coating material to improve its bonding characteristics, wear debris to get accumulated. The desired dimple parameters are chosen for the laser surface texturing. The laser surface texturing followed by a surface treatment has improved the wear-resisting performance of the contact surfaces.

Ramesh Rajesh, M. Prem Ananth, Sangam Harish, Sakthivel Balaji, R. Sivaguru

### Some Studies on Surface Roughness of AISI 304 Austenitic Stainless Steel in Dry Turning Operation

In this paper, the input variables of turning process of AISI 304 stainless steel are optimized by employing the Taguchi method under dry machining conditions. The dry turning operations are conducted at three levels of depth of cut, cutting velocity, and feed. The test results are evaluated by employing S/N ratio and ANOVA. It is revealed that the depth, cutting speed, and feed are the important input variables affecting the quality of the machined surface. The optimum surface finish is attained at the combination of lower depth, lower feed, and higher cutting speed.

D. Philip Selvaraj, P. Richard Philip

### Influence of Fiber Orientation on Mechanical Properties and Free Vibration Characteristics of Glass/Hemp Hybrid Composite Laminates

Fiber-reinforced polymer (FRP) composite materials made of synthetic fibers are commonly used in aircraft and automotive structures due to their specific property of high strength-to-weight ratio. The non-biodegradable nature of synthetic fibers and increase in demand of environment-friendly materials now made natural fibers as best alternative material to synthetic fibers. In this view, hybridization of synthetic E-glass fiber with natural hemp fiber is proposed to promote the usage of natural fibers in structural applications without much compromise in structural integrity. In the present study, the influence of fiber orientation over effective stacking sequence of E-glass/hemp hybrid composite laminates was investigated in terms of mechanical and free vibration characteristics. The hybrid composite laminates are fabricated by hand lay-up method. Two types of composite laminates were prepared in effective stacking sequence of GHHG with two different orientations fibers such as (0°/90°) and (45°/45°) for hemp fiber. The mechanical properties such as tensile and flexural strength were evaluated according to ASTM standards. Free vibration characteristics such as modal frequency and modal damping values of hybrid composite laminates are analyzed by experimental modal analysis. The results of modal frequency and mode shapes of hybrid composite beams were stated and discussed.

R. Murugan, V. Muthukumar, K. Pradeepkumar, A. Muthukumaran, V. Rajesh

### Free Vibration Analysis of Functionally Graded Beam with Linearly Varying Thickness

The present study investigates the free vibration analysis of functionally graded material (FGM) beam which is rectangular in cross section with linearly varying thickness along its axis with the help of finite element formulation. This formulation of finite element is developed based on the Timoshenko beam theory which we called as first-order shear deformation theory. In the present analysis of the beam with linearly varying thickness, the beam element has five nodes and thirteen degrees of freedom. Properties of the material used in this beam element are varying continuously according to the power law along the thickness direction. Governing equations used for the formulation of present work are derived from Lagrange’s equations. The natural frequency of beam is calculated using different boundary conditions, exponents of power law, depth to span ratios, and tapered ratios. The present beam element is accurately demonstrated by comparing the results with the available data of publications for constant thickness and for variable thickness, and some results are new and can be further considered for future researches.

Rajat Jain, Mihir Chandra Manna

### Parametric Study of Composite Plate Using Free Vibration Analysis

This paper presents the free vibration analysis of laminated composite plate to study the parametric variations on natural frequency of the plate. The parameters used for analysis are aspect ratio, number of layers in composite plate, support conditions, number of layers and fibre orientation. Finite element model of the laminated composite plate is prepared using ANSYS 13.0 software. The element chosen for the analysis is shell 281, an 8-noded, six degrees of freedom. This element is used for analysing thin to moderately thick structures. The effect of parametric variations on the natural frequency is then studied. The results obtained from the analysis are then compared with the experimental values obtained from the literature survey with a satisfactory result.

Rajendra Kumar Sadangi, Mihir Kumar Sutar, Sarojrani Pattnaik

This paper presents a free vibration analysis of hybrid composite beam under thermal gradient loading. Theoretical vibration analysis of the hybrid composite beam is performed and variation of the (z/h) with respect to Young’s modulus under variation of the thermal gradient is studied. The results obtained from the analysis of hybrid composite beam were compared with the plain composite beam and it was observed that hybrid composite beam possesses better modulus of elasticity compared to that of plain composite beam. This analysis would be vital for performing further research in this domain.

Prabhat Pradhan, Mihir Kumar Sutar, Sarojrani Pattnaik

### Computational Analysis of Boring Tool Holder with Damping Force

In the boring process, tool vibration is an important parameter due to its overhanging length and also leads to high cutting force, poor surface finish and increase in tool wear. To suppress tool vibration and increase the cutting performance, a novel idea has been developed in rheological fluid. In present work, a boring tool holder with magnetorheological damper was analysed. Magnetorheological damper received massive responsive due to their capability to reversely change from a linear, free-flowing viscous fluid to semis solid within seconds when a magnetic field is applied. In this paper, a boring tool holder was analysed using ANSYS software with damping force applied in various direction and without MR effect. The results prove that the use of Magnetorheological damper reduces tool vibration significantly.

G. Lawrance, P. Sam Paul, A. S. Varadarajan

### Comprehensive Review of the Effects of Vibrations on Wind Turbine During Energy Generation Operation, Its Structural Challenges and Way Forward

The effects of vibration cannot be overemphasized when it comes to generating energy via wind turbine. Vibration is one of the major challenges faced by the wind turbine, due to the complexity of the structure and the area of installation. This research work focuses on a compressive review of the effects of vibration occurrence on wind turbine during energy generation operations and its economical challenges’. Therefore, this research paper has reviewed various aspects of vibration effects in horizontal wind turbine such as the blades region, tower structure, nacelles compartment, and condition monitoring along with fault diagnosis models. The result from this study has shown that, there are needs to develop and implement a good reliability model, fatigue assessment process, and a well-developed monitoring model for wind turbine during operation. When these things are properly put in place, it will help to reduce unwanted vibration occurrence, eliminate unexpected failure of the wind turbine in operations, and hence sustainable energy generation from wind turbine.

I. P. Okokpujie, E. T. Akinlabi, N. E. Udoye, K. Okokpujie

### Design and Analysis of a Novel Hybrid Car Bumper Using Non-Newtonian Fluid and High-Density Polyethylene

The drivers of today’s cars are protected from frontal impacts with the help of crumple zones and composite bumpers that absorb the entire impact. However, the structural integrity is not entirely protected. In this research, a hybrid of two materials, one a non-Newtonian fluid named Oobleck and another material HDPE, was used in conjunction with creating a hybrid bumper system. The Oobleck fluid exhibits shear thickening when an impact force is applied and the material changes from a liquid to a solid state, thereby demonstrating twin characteristics. This unique property of the fluid is exploited by housing it in a HDPE tube and fixing the HDPE tube within the bumper beam. Such a combination has not been used in previous works and is a novelty. This deals with the assorted mixture properties of fluid, the materials for housing this fluid and holding it in the site and the impact strength absorbing capabilities of the designed bumper. A comparative analysis was undertaken between the prevailing bumper system and the newly designed bumper with non-Newtonian fluid. The finite element results that justify deformation experienced by the modified bumper are less compared to existing bumper, thereby resulting in less structural damage or formation of crumpled zones.

K. Praveen Jerish, J. Rakesh Kumar, R. Ramakrishnan, K. S. Vijay Sekar

### Vibration Signature-Based Monitoring on FSW Process and Verification by FEA

Experimental study conducted during joining butt weld in FSW process on Al 6061 alloy of size 50 mm width × 100 mm length × 8 mm thickness of two plates wherein the effect of the interaction between the plates, tool and the vibration that occurs during the process is investigated and reported. In this study, joining sides of the workpiece samples are artificially induced with air gaps of drilled holes in 2, 3, 5 mm diameter holes and 3 mm width × 4 mm depth of slots in random distances. The vibration behaviour of the tool and workpiece joining system is characterized by frequencies arrived in modal analysis using finite element analysis (FEA), and each mode corresponds to tool and workpiece system. Variations in the amplitudes of vibration signals in the particular range of frequencies from 6.0 to 7.0 kHz are proportional to the workpiece and significant changes in a linear pattern indicate the defective and steady joining area of workpiece. So, this method is effective in monitoring of workpiece joining in FSW process. The fast Fourier transform (FFT) analysis of the vibration signal shows the changes in individual frequencies and is used for identifying the frequency range of monitoring workpiece with gap and without gap conditions. The steady joining portions cause the vibration which corresponds to 4th region frequencies of workpiece.

Akshay Todakar, R. S. Nakandhrakumar, M. Ramakrishnan, V. Meenakshisundaram

### Power Generation from Hydraulic Shock Absorber Using Piezoelectric Material

A lot of emphasis has been laid on harvesting energy from unconventional sources these days due to environmental concerns. Harvesting energy from vibrations is one of the most promising technologies in the present day scenario like the vibrations of tall buildings, long bridges, vehicle systems, railroads, ocean waves, and even human motions. For successful harnessing of this wasted energy, a piezoelectric transducer has been used. The analysis of suspension to find stiffness and deformation is done. Also, the force acting on the suspension over bumps is found which is used to calculate the voltage. The power obtained is further calculated and possible applications of this energy generated are also being mentioned. The objective is to harvest energy from the suspension system using PZT. Model of the shock absorber and a Simulink model of quarter car suspension. Evaluation of the changes in stiffness and deflection of the suspension would be done. A way of efficient conversion of the vibration to electric power by finding the best position to place the piezoelectric material. Finally, the force during a bump is found and hence the voltage induced in PZT. Thus, the power generated and designing a circuit to store the generated power in a battery is obtained.

B. Jain A. R. Tony, M. S. Alphin, V. Yeshwant

### Static Deformation Analysis with and Without of Piezo-electric Material Attachment in Hydraulic Suspension System

A lot of emphasis has been laid on harvesting energy from unconventional sources these days due to environmental concerns. Harvesting energy from vibrations is one of the most promising technologies in the present day scenario like the vibrations of tall buildings, long bridges, vehicle systems, railroads, ocean waves, and even human motions. For successful harnessing of this wasted energy a piezo-electric transducer has been used. The analysis of suspension to find stiffness and deformation is done. Hydraulic suspension system was modelled using SOLIDWORKS and static analysis was performed using ANSYS. The static analysis results were evaluated as deformation and Von-Mises stress with and without piezo-electric material.

B. Jain A. R. Tony, M. S. Alphin, Nishanth P. Shah

### Study of Vibration and Tensile Characteristics of Multilayer Composites

In recent years, the use of composites for engineering purposes has grown enormously. Composites can be fabricated to the necessary requirements and can satisfy the required needs. The epoxy resin, used in combination with a hardener, acts as an adhesive and matrix of the composite. Glass fiber has been unanimously used along with epoxy for better mechanical properties. Various Rubbers are incorporated as the middle layer in the multilayer composite structures. Tensile and vibration tests are performed on these composites. The presence of rubber in the composite structure influences both the tensile and vibration characteristics of the multilayer composites. Hence, the tensile strength, natural frequency, and the damping factor shows variation due to the presence of rubber and this property can be exploited for engineering purposes.

D. Vishal, M. Selvaraj, S. Vijayan

### Influence of Vibro-isolator Attachment for a Jackhammer to Reduce Vibration Discomfort

Jackhammers are widely used in the construction industry to break up rock, pavement and concrete. They are generally powered by compressed air, electric motors, or hydraulics and can generate a large force for drilling and demolition. However, while they are an efficient tool for this purpose, they also pose a serious danger to the worker, due to the vibrations transmitted. Prolonged exposure to these vibrations can cause ailments such as vibration white finger, Raynaud’s disease and carpal tunnel syndrome (CTS). The objective of this research is to design and fabricate a vibro-isolator attachment to damp and absorb the range of harmful vibrations transmitted to the occupant. The attachment is clamped on top of the jackhammer and makes use of two helical springs in parallel to reduce the higher amplitude vibrations. Handles are provided above the springs for the user to grip the attachment and hence, the jackhammer. The new design, setup feels worker much less hand-arm vibration without reducing the downward drilling force of the jackhammer. Hence, the newly designed vibration isolation, attachment reduces the hand-arm vibration, and the jackhammer can be operated at full power without compromising on the health of the occupants.

B. Jain A. R. Tony, M. S. Alphin, Vishal Venkatesh