Department of Mechanical engineering
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Item Vibration suppression of flexible beams for robotic assembly using vision and wrist motion(ACM Digital Library, 2023-11) Rout, Bijay KumarIndustrial robots are used in assembly operations to increase the productivity of the manufacturing process. In this operation, a robot grasp either a rigid or flexible object like beams, wires and sheets that may encounter undesired vibration in this object due to high speed motion of the robot. The present work designs a high-level control strategy using a robot vision system to suppress the vibrations of the flexible beams during the assembly process. The robot vision approach is used to detect the beam held by the gripper of the robot and measure the dimensions keeping an account of the change in perspective. The free response of the flexible beam is used for system identification regardless of dimension and material properties. To suppress the vibration of the flexible beam actively, the proposed high-level controller uses the wrist motion of the robot. The efficacy of the proposed approach is demonstrated by implementing it on a commercially available ABB 1410 industrial robot without modifying its controller for the beam-in-slot assembly operation. The proposed controller can suppress vibration amplitude up to 97.83% within 2.36 s and reduce suppression time by 96.23% compared to the control to no control scenarioItem Numerical investigation on design parameters of orifice plate for positioning of workpiece in cavitation zone for cavitation machining(Taylor & Francis, 2024-01) Rout, Bijay Kumar; Bera, Tufan ChandraThe recent development of non-traditional machining techniques, such as cavitation machining (CM), has been gaining traction amongst researchers due to its sustainable nature. The present research focuses on the use of computational fluid dynamics (CFD) model to predict the location of workpiece in the fluid domain and bubble distribution during CM process. For efficient CM, the correct positioning of a workpiece in cavitation zone is essential, as the implosion of the cavity bubble leads to formation of micro-jet and shock waves for a few milli-to-microseconds generating high temperature and pressure on workpiece. The aim is to harness cavitation phenomena in material processing, particularly by using orifice plates as a common tool to induce hydrodynamic cavitation. To generalise the investigation, the flow simulation through orifice plate with different aspect ratios (l/d) are carried out. For the bubble distribution and their diameters, the Lagrangian discrete phase model (DPM) is used in the downstream side of the flow domain. Using this information, bubble dynamics have also been investigated using the Keller–Miksis (KM) model to compute the implosion time and intensity in the zone. The presented exploration determines the orifice dimensions to optimize implosion intensity, ensuring precise workpiece placement in real-time CMItem Vision based control strategy to suppress residual vibration of flexible beams for robotic assembly using wrist motion(Sage, 2023-12) Rout, Bijay KumarAutomated assembly tasks require industrial robots to improve the efficiency of the manufacturing process. Most rigid or flexible objects handled by robots vibrate due to motion and transient disturbance. This work proposes an active vision-based vibration suppression strategy for flexible beams by providing motion to the wrist of a robot during robotic assembly process, which reduces the time to suppress vibration. The proposed method uses a cheap monocular camera to identify objects through a virtual marker and measure their dimensions. Subsequently, finite element method based mathematical model of a flexible beam predicts the maximum error. The proposed second stage controller determines the controller input in terms of wrist motion based on the predicted maximum error. The performance of the controller is assessed through simulations and experiments on metallic beams with different material characteristics and dimensions. The controller suppresses vibration amplitude within a safe limit so that object is inserted into the slot. It was observed from experiments that the controller can reduce vibration amplitude by ~96% in less than 2 s and decrease suppression time up to ~97%. These improvements were achieved without disturbing the internal robot controller.Item Deep learning based techniques to develop & enhance assistive gear for visually impaired(IEEE, 2024-12) Rout, Bijay KumarThis work investigates existing solutions tailored for the visually impaired, focusing on economically viable options for non-first-world communities. The exploration involves developing a real-time obstacle-tracking model using the YOLO (You Only Look Once) algorithm and Text-to-Speech synthesis to provide auditory cues. This effort yields improvements in assistive technology, though it still faces limitations in algorithmic precision and user feedback integration. The research paves the way for refining this technology and envisions its seamless integration into the daily lives of the visually impaired. The findings enhance the performance of assistive technologies, especially for distances less than 1.5 meters. The results show an inaccuracy of less than 10%, translating to a margin of 10−15 cm for objects located one meter away. This work thus provides increased independence and confidence for individuals with visual impairments in navigating and interacting with their surroundings.Item Optimization strategy for object picking and placing on table by industrial robot(IEEE, 2024) Rout, Bijay KumarObject sorting is a problem of separating objects of different kinds based on shape, size, or any other feature into separate stacks to process those separately. In the food processing industry, object sorting is used to separate fruits of different grades. Separating fruits into different grades is essential for quality control. Manual sorting is slower and costs more than automated sorting. This paper presents a novel solution for the object sorting problem using YOLOv8x and various optimization algorithms (ILP, GA and PSO). Here, the object sorting problem is solved by modelling it as a TSP. Through experiments, it was observed that a PSO-based approach could solve the object-sorting problem efficiently. The PSO method obtained a near-optimal solution with 42% less processing time than those obtained from the ILP method, which would enhance the productivity and performance of the industrial robotItem Thermal hydraulic performance and characteristics of a microchannel heat exchanger: experimental and numerical investigations(ACM Digital Library, 2025-02) Aneesh, A.M.This paper presents extensive fluid flow and Heat Transfer studies conducted through an experimental setup followed by a detailed three-dimensional (3D) numerical analysis of the same setup using a commercial package for computational fluid dynamics (CFD), known as cfd-ace® for additive-manufactured counterflow AlSi10 Mg microchannel heat exchangers (MCHEs). A detailed 3D computational model of the experimentally tested MCHEs was built and analyzed using the commercial software cfd-ace® for the same experimentally tested operating conditions. The computational model results are in good agreement with experimental data of tested MCHE within +2% to +7% and ∼0% to −13.5% variation for cold and hot fluids for the entire set of design of experiments (DoEs). This percentage disagreement may be due to various factors, such as manufacturing deviation within tolerance, longitudinal conduction, variation in the thermal conductivity of the material after heat treatment, variation in environmental temperature, sensor deviation, and surface roughness of internal channels. Instead of Stainless steel (SST), AlSi10 Mg was used because of its lower manufacturing cost because AlSi10 Mg was lighter than SST, though its thermal conductivity is almost ∼8–10 times more than that of SST. A higher thermal conductivity is not good for MCHEs because it leads to higher longitudinal conduction, which eventually degrades the performance of MCHEs in terms of effectiveness. MCHE effectiveness is also reduced by ∼12% to 18% owing to longitudinal conduction from ideal effectiveness.Item Atomic scale insights into material removal mechanisms in nanoscale machining of copper beryllium(Sage, 2023-12) Kumar, Amit; Sharma, AnujThe heterogeneous nature of the copper beryllium (CuBe) workpiece because of the presence of hard particles tends to affect material removal. When machining a CuBe material, it is anticipated that the mechanism of cutting and surface formation may differ from those seen when cutting a homogenous Cu material. Although these mechanisms are popular for the diamond turning of homogeneous materials, they have not been thoroughly studied in relation to CuBe alloys, which contain hard beryllium precipitates. Therefore, the effect of hard particles in the workpiece specimen on the nano-regime diamond turning of CuBe alloy needs to be understood. To explain the influence of Beryllium (Be) particles on the cutting tool and the workpiece surface, a molecular dynamics (MD) simulation was performed. It is revealed that the material removal mechanism in the case of CuBe is phase-dependent. Ductile machining is dominant in the Cu phase, and brittle fracture is dominant in the Be rich phase. It is also observed that the a/r ratio equal to 1 is suitable for cutting in the Cu phase and for ductile regime machining conditions in the Be phase. The a/r ratio higher than 1 causes higher cutting forces, and thus shear plane cutting takes place, which leads to a higher amount of material removal.Item A comprehensive framework for analysis and evaluation of factors responsible for sustainable growth of electric vehicles in India(Elsevier, 2022-12) Digalwar, Abhijeet KumarThe Indian transport sector powered by fossil fuels is primarily responsible for creating severe issues like greenhouse gas emissions, foreign fuel dependency, economic burden, and chronic health effects. To mitigate these severe issues, electric vehicles (EVs) are positioned as an alternate green and clean technology, which can potentially enable the efficient transition to a sustainable low-carbon emission transportation system and preservation of natural scarce resources. Despite announcing favorable policy measures to encourage EV adoption, the multiplicity of potential factors with mutual interaction has resisted its penetration in several countries. Though researchers have identified the critical factors, the question “How do these factors mutually interact among themselves?” has remained largely unanswered in empirical research. Unpacking the relationship between the factors will empower manufacturers and policymakers in strategic planning, and devising suitable measures in controlling the factors. The primary goal of this research is to undertake a thorough assessment and give a brief understanding of the various factors responsible for sustainable growth of EVs market in India. Factors are identified from past academic literature and experts' interviews. Study further empirically validated the identified factors. Then integrated Decision-Making Trial and Evaluation Laboratory (DEMATEL) – Interpretive Structural Modeling (ISM) approach has been used to demonstrate the interrelationship and hierarchal structure of the factors. The present study will be useful to the manufacturers, policymakers to focus on the gray area so that they can expedite the growth of EVs deployment in India.Item A geospatial integrated multi-criteria approach for assessment of solar and wind energy potentials with economic and environmental analysis(AIP, 2023-12) Digalwar, Abhijeet KumarIndia has made an international commitment to generate about 50% of its total energy needs from renewable energy sources by 2030. Here, to meet such a commitment, this study developed high-resolution (1 × 1 km2) geospatial solar and wind geographical potential maps with an aim to calculate the theoretical and technical potentials with economic and environmental sustainability. These geographical potential maps are developed by taking into account 13 evaluation and restriction factors pertaining to technical, economic, and socio-environmental categories. The investigation identifies that Rajasthan, Karnataka, and Gujarat have a plurality of extremely favorable land areas for solar and wind energy sources. Furthermore, the results imply that appropriate planning for the installation of renewable projects at the identified optimum locations can fulfill India's commitments with regard to an optimal energy mix scenario, with energy available twice the available potential for consumption in 2030. Furthermore, with the least average levelized cost of energy of 38.8 $/MWh (2.83₹/kWh) and 42.3 $/MWh (3.09₹/kWh), solar and wind energy sources are potentially more appealing and affordable than conventional energy sources. The findings of this study will also significantly advance India's attempts to accept and develop renewable energy sources, helping to realize the government's objective for sustainable electricity productionItem Industry 4.0 implementation: evidence from Indian industries(Springer, 2023-12) Digalwar, Abhijeet KumarThe emergence of “Industry 4.0” signifies a new industrial era, where various technologies converge to provide digital solutions. Industry 4.0 (I4.0), encompasses a range of digital technologies that profoundly impact manufacturing businesses. However, there is limited knowledge regarding how businesses utilize these technologies. This paper addresses the pillars of Industry 4.0, a crucial part of the next industrial revolution for Indian manufacturing industries aiming to become competitive smart factories in the global market. A survey of 73 Indian industries assessed their current technologies. Implementation criteria for Industry 4.0 in Indian industries were established based on the survey results. The findings reveal that customer satisfaction and quality are top priorities for Indian industries. While most industries have implemented Industry 3.0 practices, awareness and adoption of I4.0 still pose challenges, particularly for SMEs. This report analyzes the technological status of Indian industries, identifies the gap, and provides a roadmap for adopting Industry 4.0. Bridging this knowledge gap and embracing Industry 4.0 can enhance competitiveness, drive innovation, and meet the evolving demands of the global market. The transition to smart factories powered by Industry 4.0 unlocks new opportunities for India’s industrial sector, propelling it towards a prosperous future.