Vellore Institute of Technology (VIT) is a private university located in&nbsp;Tamil Nadu, India. Founded in 1984, as Vellore Engineering College, the institution offers 20 undergraduate, 34 postgraduate, four integrated and four research programs. It has campuses in Vellore, Amravati, Bhopal and Chennai.

VIT is one of the top ranked private universities in India according to NIRF, THE and QS Rankings.&nbsp;Govt. of India has recognized&nbsp;VIT, Vellore as an&nbsp;Institution of Eminence. This has allowed VIT to take independent quality initiatives and move up in world ranking.

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VIT University

Department of Design and Automation

This paper focuses on navigation of a humanoid robot cluttered with obstacles, avoiding collisions in static environment using Prim’s algorithm. Prim’s algorithm is a minimum spanning tree (MST) method with greedy approach which uses the concept of sets. It generates the MST by selecting least weights from the weighted graph and randomly forms disjoint sets with picking one least weight edge from the ones remaining for creating node incident to form the tree. Similar approach repeats for selecting all ‘n – 1’ edges to the tree which is the path direction to humanoid NAO. The developed algorithm is implemented in both simulation and experimental platforms to obtain the navigational results. The simulation and experimental navigational results confirm the efficiency of the path planning strategy as the percentage of deviations of navigational parameters is below 6%. © 2021, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.

World University root node

School of Mechanical Engineering

Vellore Campus

Lecture Notes in Networks and Systems

Global Path Optimization of Humanoid NAO in Static Environment Using Prim’s Algorithm

The main aim of the research is to investigate the microstructure and mechanical properties of advanced corrosion resistant alloy C-2000 welded with Laser Beam Welding (LBW) process. Laser welding is a highpower- density fusion-welding process that produces high aspect ratio welds with a relatively low heat input compared with other arc-welding processes. Dinolite macro analyzer was used to determine the aspect ratio and other defects in the weld joint. The micro structural characteristics of the weldment are analyzed with Optical and Scanning Electron Microscope (SEM). The micro segregation of alloying element in interdendritic regions is quantified by Energy dispersive X-ray spectroscopy (EDS). Microstructure examination shows that mild copper microsegregation is observed near the interdendritic region. The strength, ductility, hardness and toughness of weld joints are evaluated by tensile, Vicker's hardness and Charpy impact test respectively. The result outcome shows that mechanical properties are slightly lower than base metal due to the combined existence of columnar and equiaxed grains in the weld fusion zone. © 2021 elsevier ltd. all rights reserved.

Materials Today: Proceedings

Investigation on mechanical and microstructure characteristics of nickel based c-2000 super alloy using laser beam welding

This paper focuses on building a bicycle prototype which is can balance itself with the help of a reaction wheel. The bicycle prototype does not employ a rider for this task. This concept can be extremely helpful as a safety mechanism for future motorcycles wherein the rider can save himself from a crash, if he/she loses control over the motorcycle. The bicycle uses a controlling mechanism to prevent itself from falling on either sides in static condition. It uses an inertial measurement unit (IMU) sensor for detecting changes in the roll angle and reacts to maintain a constant vertical position. Reaction involves rotation of the reaction wheel by the motor which gets its input signal from a controller which works in conjunction with the sensor to analyze the data. Final aim is to build a prototype of the self-balancing bicycle and get an overview of the recent developments in the field of autonomous driving. © 2021, Springer Nature Singapore Pte Ltd.

Lecture Notes in Mechanical Engineering

Development of Reaction Wheel Controlled Self-Balancing Bicycle for Improving Vehicle Stability Control

In the present study, the dynamic characterization of the glass fiber-reinforced polymer (GFRP)-laminated composite cylindrical open shallow shell panels is explored with the experimental and numerical approach. In the finite element modeling (FEM), the governing equilibrium equation of the cylindrical shell panel is developed with higher-order shear deformation theory by considering the nine-noded rectangular elements. The convergence and validation study of the present FEM is accomplished with the available literature. The cylindrical laminated composite shallow shell panels are fabricated with a curvature radius of 0.8 m, and the experimentation on the free vibration investigation is performed with various boundary conditions; then, the experimental outcomes are compared with the present FEM to verify the effectiveness. The detailed parametric investigation is executed to explore the impact of curvature radius (R), boundary conditions, thickness ratio, aspect ratio (L/B), and stacking sequence on the structural response of the cylindrical laminated composite shallow shell panel. Transverse vibration response of the GFRP cylindrical laminated composite shallow shell panel is also performed with the various curvature ratios at clamped at all end conditions. © 2021, The Author(s), under exclusive licence to Springer-Verlag GmbH, DE part of Springer Nature.

Archive of Applied Mechanics

Assessment on dynamic characterization of the cylindrical laminated composite shallow shell panel through experimental and numerical approach

The increasing demand for applying shape memory polymer to tissue culture and biomedical engineering has opened up research opportunities in the field of 4D Printing. The biocompatibility of the scaffolds as a culture medium resulted in the use of plant-based polymers to provide an ambient environment for the growth of cells. This research investigates the 4D printing of acrylated epoxidized soybean oil (AESO), a plant-based shape polymer. The objective of the present work is to establish the relationship between the 4D printing parameters (laser power frequency and print speed) and different properties of the printed material viz. tensile stress, surface roughness, wettability, recovery time, strain fixity and glass transition temperature. The maximum fixity was about 85%, while the recovery time as low as 1.6 s. The print parameters are optimized using regression modeling and multi-objective optimization techniques. The shape memory effect of the polymer is demonstrated by printing samples at the optimized conditions. Dynamic mechanical analysis is performed to evaluate the variation in the glass transition temperature of AESO at specific print parameters. The adoption of an optimal set of laser frequency and print speed is found to improve the properties of AESO, while built by micro stereolithography (micro-SLA). © 2021 Wiley Periodicals LLC.

Journal of Applied Polymer Science

4D printed stereolithography printed plant-based sustainable polymers: Preliminary investigation and optimization

Drilling of micro-cooling holes in turbine blades on hard material like Inconel 625 is one of the noteworthy applications of micro-drilling. An experimental investigation on the hole quality assessment and drill bit tool life while micro-drilling of Inconel 625 is not explored in detail. This paper presents the experimental study and multi-response optimization of test parameters of Inconel 625 in micro-drilling conditions using desirability approach. Test parameters are micro-drill diameter, spindle speed, and feed rate. The micro-drilling test, based on the Taguchi L27 design, is performed on a 2-mm plate thickness of Inconel 625 with uncoated micro-drill. After each drilling test, the hole properties including hole diameter, circularity error, overcut, taper ratio, cylindricity and hole damage factor are measured, and the results are examined. In addition to that, the number of micro-holes that can be drilled is analysed to observe the lifelong tool performance on hole quality assessment. As a result, the number of holes drilled before tool breakage is 25 in magnitude. The deviation in hole diameter, cylindricity, circularity error, roundness, overcut, taper ratio, and hole damage factor obtained is increased to 5.5%, 87.2%, 50.5%, 5.7%, 77.4%, 20% and 5.4% from 1st hole to 25th hole at an optimal level of high tool diameter, low speed, and high feed rate. The most significant drilling parameters for the above-studied response factor are tool diameter and spindle speed. From the results, the 0.8 mm is the most suitable tool diameter for hole quality achievements and productivity in practical micro-drilling applications. © 2020, King Fahd University of Petroleum & Minerals.

Arabian Journal for Science and Engineering

Experimental Investigation and Parametric Optimization on Hole Quality Assessment During Micro-drilling of Inconel 625 Superalloy

Few researchers have presented solids friction factor correlations for the fluidized dense phase conveying of fine particles or powders. Pressure drop for conveying can be predicted using these correlations. These correlations predict the pressure drop with minimum error margin for a definite pipeline configuration or for some specific types of conveying materials. Few researchers have applied their correlations for different pipeline configurations (of different pipeline lengths or diameters) or different conveying materials to predict the pressure drop. In this paper, different solids friction factor correlations for the fluidized dense phase conveying have been considered which are available in the literature and the behaviour of these correlations have been studied under length scale-up or diameter scale-up conditions. It has been observed that only few correlations exhibit natural pressure drop variation with change in pipeline length or pipeline diameter. © 2020 Institute of Materials, Minerals and Mining and Informa UK Limited, trading as Taylor & Francis Group.

Tribology - Materials, Surfaces and Interfaces

Review and analysis of solids friction factor correlations in fluidized dense phase conveying

An increasing number of on-road vehicles have increased the average duration of the engine's low-load and speed operation. This prolonged status of engine running is called idling and is the source of higher fuel consumption, increased engine wear, and spiked emissions. Also, to address the twin crisis of fossil fuel scarcity and higher engine-out emissions the present-day vehicles need suitable alternate fuels. Blending of Orange Peel Oil (OPO) with diesel is a promising solution to contain the reparations caused by idling emissions and fuel consumption. However, to ensure complete functionality of the OPO-diesel blend during idling, the combustion, vibrations, and sound characteristics need to be analysed. Hence, the present work calibrates the engine operating parameters for vibro-acoustic and combustion characteristics of a commercial vehicle diesel operating under idling conditions for pure diesel and OPO blends (10% and 20%). Vibrations, sound levels, and combustion characteristics were measured for diesel, OPO 10, and OPO 20 fuel blends. Experiments were conducted as per the Design of Experiments determined by Central Composite Design and the engine parameters were calibrated based on the optimised results using Response Surface Methodology. The results revealed that OPO20 performs better than OPO10 compared to pure diesel, as it displayed similar vibration characteristics and improved heat release rate by 8% while maintaining the same noise levels. The only deviation in vibration behaviour is at the engine mount which reported of 77% average increase along all three axes, while vibration in all other test points varied within a range of 5%. © 2020 Elsevier Ltd

Fuel

Calibration of engine parameters and fuel blend for vibration and noise characteristics in CRDI engine fuelled with low viscous biofuel

Usually, heat-treated electroless NiP deposits (NiP) were cooled using air quenching (AQ) process for enhancing its surface properties. As of now, no research work reported the surface characteristics of heat-treated NiP followed by water quenching (WQ) process. Hence, a novel attempt has been made to report the preliminary investigation on the properties of WQ-NiP. The deposits were heat treated (400°C, 500°C, 600°C and 700°C) at the rate of 0.5°C/s followed by air and water cooling. Comparative investigations have been made between the as-plated, AQ-NiP, WQ-NiP in terms of phase structure, crystallite size, residual stress, rockwell hardness, microstructure, and work of adhesion. Additionaly, the failure mechanisms of various heat-treated NiP during indentation were investigated and reported in this article. There is a restriction observed in the growth of crystallite for WQ-NiP as compared to the as-plated and AQ-NiP. The solubility of the intermediate phases has induced compressive residual stress for both AQ-NiP and WQ-NiP at 600°C and 700°C. Nickel oxide precipitate was observed in the microstructure of AQ-NiP and WQ-NiP heat treated at 700°C. The work of adhesion is considerably increased for WQ-NiP as compared to AQ-NiP. Maximum hardness of about 53.7 HRC was obtained for WQ-NiP treated at 400°C. © 2021

Surfaces and Interfaces

A novel water quench approach for enhancing the surface characteristics of electroless nickel phosphorous deposit

This study intended to optimize the process parameters of the friction stir welding (FSW) technique to maximize the mechanical properties of the AA6082/B4C composite weldments. The metal matrix composites are prepared with aluminum alloy 6082 and boron carbide particles of 10µm size by using a stir casting technique. The central composite design technique is applied to design the FSW experiments. The experiments were carried out in butt joint configuration by varying welding transverse speed, axial load, plunge depth, and tool rotational speed. The optimum parameters are estimated by considering output responses such as ultimate tensile strength and microhardness. The effect of process parameters on output responses was analyzed graphically. Two optimization techniques, namely genetic algorithm and desirability function approach, are implemented to identify the optimal values of process parameters. The results obtained by both optimization techniques are in good agreement. The optimum values are validated with experimental results. © 2021, ASM International.

Department of Manufacturing Engineering

Journal of Materials Engineering and Performance

Multi-Performance Optimization in Friction Stir Welding of AA6082/B4C Using Genetic Algorithm and Desirability Function Approach for Aircraft Wing Structures