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This paper discusses the development and design of two wheeled-type In-Pipe Inspection Robots (IPIRs), Kuzhali I and Kuzhali II, which were created to address the limitations of traditional human inspection methods and earlier robot designs. Specifically, the robots aim to overcome the motion singularity experienced by IPIRs when navigating through curved pipes. Kuzhali I was developed with wheels mounted at an asymmetric angle, which enables the wheels to maintain contact with the pipe's surface, preventing motion singularity. However, Kuzhali I had limitations due to its prismatic mechanism, and thus Kuzhali II was developed with a telescopic mechanism to allow it to pass through vertical pipes with obstacles. Motion analysis was conducted on both robots to demonstrate how they overcome motion singularity and navigate through straight and curved pipelines. Simulation results showed that the forces acting on the robots' wheels fell within 5 N to 12 N, demonstrating stability while navigating pipeline junctions. Experimental tests were conducted on Kuzhali II, and the results were compared to simulation results, showing an error of less than 5%. The results of the experiments indicate that Kuzhali II is safe to use for pipeline inspection, can navigate through vertical pipelines with ease and can overcome motion singularity in curved pipes. These robots offer a faster, more accurate, and safer alternative to human inspection, which can reduce the risk of pipeline failures and associated environmental and safety hazards. [ABSTRACT FROM AUTHOR]

Intelligent machining requires the online adaptation of the machining parameters to improve tool life and product quality and to reduce machining costs. This article presents a novel hybrid adaptive control (HAC) system for a drilling process. The HAC system is a combination of two adaptive controls: geometric adaptive control (GAC) and adaptive control by optimisation (ACO). It keeps the roughness of the holes within tolerance without compromising tool life. A response surface model (RSM) is used for modelling the drill wear and surface roughness with speed, feed, acceleration and force signals as inputs. The model predicts the wear and roughness with prediction accuracies of 97.1% and 93.6%, respectively. The roughness control is achieved through a Massachusetts Institute of Technology rule and tool wear is minimised by genetic algorithm optimisation. The adaptive algorithms are simulated and validated for the machining conditions given by the adaptive algorithms. The results show an improved tool life of 7% and surface roughness of 11%. [ABSTRACT FROM AUTHOR]

Efficacy of eight insecticides along with five plant extracts were tested during rabi 2017-18 and kharif 2018-19 at Agricultural Research Station, Virinjipuram, Vellore, Tamil Nadu. Four applications of treatments viz., acetamiprid 20 SP @ 30 g ai ha-1, imidacloprid 17.8 SL @ 44.5 g ai ha-1, spiromesifen 240 SC @ 120 g ai ha-1, thiacloprid 240 SC @ 120 g ai ha-1, thiamethoxam 25 WG @ 50 g ai ha-1, diafenthiuron 50 WP @ 250 g ai ha-1, dimethoate 30 EC @ 300 g ai ha-1 and profenophos 50 EC @ 300 g ai ha-1, azadirachtin 10000 ppm @ 3.0 mL L-1, neem seed kernel extract 5%, the leaf extracts of neem, Bougainvillea and sorghum/coconut at 10% along with an untreated check at one month interval on 30 day old plants were given. The results showed that spraying of spiromesifen (3.0 Nos. per 3 leaves) was found to record the lowest population of whitefly throughout the crop period followed by thiacloprid (3.3 Nos. per 3 leaves) and thiamethoxam (3.4 Nos. per 3 leaves). The highest population reduction of 79.2, 77.6 and 76.8% was achieved in plots treated with spiromesifen, thiacloprid and thiamethoxam, respectively, over untreated check. With respect to viral disease, spraying of spiromesifen recorded the least incidence of mosaic (4.4%) followed by thiacloprid (5.2%), thiamethoxam (5.9%) and azadirachtin (6.2%). The plots treated with spiromesifen, thiacloprid and thiamethoxam recorded the highest fruit yield of 28.8, 28.0 and 27.2 t ha-1, respectively, with 36.6, 32.9 and 29.3% increase over untreated check and also the highest cost: benefit ratio [ABSTRACT FROM AUTHOR]

A study on the development of biointensive module was carried out at Agricultural Research Station (ARS), Virinjipuram during 2017-19 against viral and phytoplasma diseases of brinjal. The module thus developed was tested in two locations viz., ARS farm, Virinjipuram and in farmers’ field at K.V. Kuppam block of Vellore district to assess the performance of biointensive Integrated Disease Management (BIDM) module against the mosaic, little leaf disease and whitefly during Kharif 2020. The results revealed that the BIDM was found superior in minimising the mosaic incidence in both locations tested and recorded 5.16 and 6.12 per cent also with lowest little leaf incidence. The lowest whitefly population was also recorded in bio-intensive module adopted plots when compared to farmers’ practice at all stages of crop growth. At 30 days after transplanting (DAT), the whitefly population of 4.45 and 3.77 Nos per plant was recorded at ARS, Virinjipuram and in farmers’ field. With respect to fruit yield, an adoption of bio-intensive module registered a significantly higher yield both at ARS farm (34.02 t/ha) and in farmers’ field (30.36 t/ha) coupled with higher benefit cost ratio of 5.84 and 5.18, respectively. Where as in farmers’ practice the lowest fruit yield of 31.71 t/ha with BC ratio of 5.57 at ARS farm and 25.68 t/ha of fruit yield with CB ratio of 1:4.43 in farmers’ field were recorded. [ABSTRACT FROM AUTHOR]

Four applications of treatments viz., acetamiprid 20 SP @0.3gl-1, imidacloprid 17.8 SL @0.5 ml l-1, spiromesifen 240 SC @1.0 ml l-1, thiacloprid 240 SC @1.0 ml l-1, thiamethoxam 25 WG @0.4 g l-1, diafenthiuron 50 WP @1.0 g l-1, dimethoate 30 EC @2.0 ml l-1 and profenophos 50 EC @2.0 ml l-1, azadirachtin 10000 ppm @3.0 ml l-1, neem seed Kernel extract 5%, the leaf extracts of neem, Bougainvillea and sorghum/coconut at 10% along with an untreated check at one month interval on 30 day old plants were given. The results showed that spraying of spiromesifen 240 SC (3.05 Nos./3 leaves) was found to record the lowest population of whitefly throughout the crop period followed by thiacloprid 240 SC (3.28 Nos./3 leaves and thiamethoxam 25 WG (3.39 Nos./3 leaves). The highest population reduction of 79.16, 77.59 and 76.84% was achieved in plots treated with spiromesifen 240 SC, thiacloprid 240 SC and thiamethoxam 25 WG, respectively over untreated check. With respect to viral disease, spraying of spiromesifen 240 SC @1.0 ml l-1 recorded the least incidence of mosaic (4.39%) followed by thiacloprid 240 SC @1.0 ml l-1 (5.22%), thiamethoxam 25 WG @0.4 g l-1 (5.87%) and azadirachtin 10000 ppm @3 ml l-1 (6.22%). The plots treated with viz., spiromesifen 240 SC, thiacloprid 240 SC and thiamethoxam 25 WG recorded the highest fruit yield of 28.79, 28.01 and 27.24 tonnes ha-1, respectively with 36.63, 32.93 and 29.28% increase over untreated check and also the highest Cost: Benefit ratio. [ABSTRACT FROM AUTHOR]

Cryogenic treatment is a thermal treatment process in which the parts are usually cooled to temperatures below −70 C (< 203 K) to induce metallurgical changes in materials. The treatment has shown a significant performance improvement in most of the ferrous materials and it's alloy, by transforming retained austenite to martensite and precipitating secondary carbides. However, the effect of such low-temperature treatment on highly stable super hard material like tungsten carbide (commonly referred to as "cemented carbide") is uncertain. But researchers have reported precipitation of eta-phase carbides, densification of cobalt binder, refinement of tungsten carbide grains, phase transformation of cobalt, and changes in residual stress in cryogenically treated tungsten carbide (WC-Co) material which resulted in increased hardness and wear resistance. Hence, this paper focuses on summarizing the cryogenic treatment parameters used in different studies, the rate of performance improvement in different applications, and reported mechanical and metallurgical changes, which would serve as a pool of knowledge for future researchers. [ABSTRACT FROM AUTHOR]

Accuracy and safety of tank guns are dependent a great degree on the condition of its gun bore. Many parameters affect accuracy and safety and have strong and complex interdependencies. While it is extremely difficult to monitor all these parameters during battle conditions, it is also essential to enhance the accuracy of the gun by measuring and compensating these parameters. Among all, bore wear and bore centreline are predominant factors. The surface characteristics of the bore also are indicative of potential accidents/deterioration, which should be monitored continuously. Hence, condition monitoring of tank gun bore characteristics in near real-time is an impending need with huge potential for enhancing the combat effectiveness of tank formations. This paper analyses various bore parameters affecting accuracy and safety and proposes a comprehensive condition monitoring method that uses vision camera, thermal camera and mechanical profiler. This integrated approach provides enhanced accuracy in measuring surface characteristics of tank bore that has been partially validated. [ABSTRACT FROM AUTHOR]

Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of FME Transactions is the property of University of Belgrade, Faculty of Mechanical Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper, monitoring of amplitude variation in the torsional-axial frequency is proposed for evaluating drill flank wear. Vibration signals were captured from the experiments resulting to the drilling process and investigation was focused on the role of torsional-axial coupling on instability predictions arising as a result of drill flank wear in the frequency spectrum. The first and second modes of torsional axial coupling frequencies were found through use of finite element analysis (FEA) and verified using experimental modal analysis (EMA) by the resonance frequency test. The proposed strategy uses dominant peaks of torsional-axial first mode (Tp1) and second mode (Tp2) frequency. The ratio of torsional-axial amplitudes (TP1/TP2) was considered for the monitoring and the evaluation of drill wear and also to nullify process parameter variation. Drill frequencies verified through experimental study showed their capability of predicting drill flank wear. The validation showed the proposed methodology having 80% accuracy and its ability for effective use for monitoring tool wear. [ABSTRACT FROM AUTHOR]

The high yielding blackgram variety VBN 8 is a cross derivative of VBN 3 x VBG 04-008. Average yield of VBN 8 is 900 kg/ha which is 11.9 and 13.5 percent increased yield over the check varieties VBN 6 (804 kg/ha) and CO 6 (793) respectively. It matures in 65 - 70 days. Under irrigated condition, it performed well by recording 988 kg/ha and the yield increases was 15.29 and 22.28 per cent over the check varieties VBN 6 (857 kg/ha) and CO 6 (808 kg/ha) respectively. Under rainfed condition, this variety recorded 871 kg/ha with 23.20 and 25.87 per cent yield increase over the above checks varieties. The special features of this new variety is determinate plant type with synchronized maturity and highly resistant to Mungbean Yellow Mosaic Virus (MYMV) disease, resistant to leaf crinkle and moderately resistant to powdery mildew diseases. [ABSTRACT FROM AUTHOR]

Cemented carbide, a generic name applied to the tungsten carbide-cobalt (WC-Co) metal matrix composite is one of the most commonly used material in cutting tool industries. Generally, thermal treatments are not applied to such super hard tool materials as they are highly stable and don't react to such treatments. In this research, cemented carbide tool with low and medium cobalt content were cryogenically treated and its effect on key metallurgical and mechanical properties were studied. The result shows that cryogenically treated cemented carbide tools have 11.1% and 8.3% better flank and nose wear resistance. Metallurgical evaluations revealed the microstructural changes. [ABSTRACT FROM PUBLISHER]

Nowadays, finishing operation in hardened steel parts which have wide industrial applications is done by hard turning. Cubic boron nitride (CBN) inserts, which are expensive, are used for hard turning. The cheaper coated carbide tool is seen as a substitute for CBN inserts in the hardness range (45-55 HRC). However, tool wear in a coated carbide tool during hard turning is a significant factor that influences the tolerance of machined surface. An online tool wear estimation system is essential for maintaining the surface quality and minimizing the manufacturing cost. In this investigation, the cutting tool wear estimation using artificial neural network (ANN) is proposed. AISI4140 steel hardened to 47 HRC is used as a work piece and a coated carbide tool is the cutting tool. Experimentation is based on full factorial design (FFD) as per design of experiments. The variations in cutting forces and vibrations are measured during the experimentation. Based on the process parameters and measured parameters an ANN-based tool wear estimator is developed. The wear outputs from the ANN model are then tested. It was observed that as the model using ANN provided quite satisfactory results, and that it can be used for online tool wear estimation. [ABSTRACT FROM AUTHOR]

Tool wear and the surface roughness of the workpiece are vital parameters in machining components that affect cost, quality and productivity. This paper describes an adaptive control strategy for a drilling process to optimise the machine parameters and minimise the tool wear and surface roughness. An adaptive neuro fuzzy inference system (ANFIS) is used for modelling the tool wear and surface roughness. Speed, feed and acceleration signals obtained during drilling are used as inputs to the ANFIS model. Bosed on the mode! output, multi-objective desirability optimisation is applied to obtain the optimal feed and speed. Individual desirability functions of tool wear and surface roughness are combined to form the composite desirability. The fuzzy inference system serves to provide the optimal speed and feed based on the composite desirability. A neural predictive controller is used to control the simulated computer numerical control (CNQ servo drive systems. The ANFIS model of tool wear and surface roughness was found to predict values with an error of 6% for tool wear and 4. l%for surface roughness. The proposed adaptive control output shows a deviation of ±2 mm/min for the feed drive and of ±7 r/min for the speed drive. [ABSTRACT FROM AUTHOR]

This study presents a reliable methodology for normalisation of a vibration signal for distance variation through sensor positioning in drilling using the artificial neural network (ANN) technique. Experiments were conducted and vibration signals were recorded for the purpose of estimating the possibilities of tool wear during the drilling process. The results obtained indicate the effect on tool wear monitoring due to the amplitude variation with the distance between the accelerometer and the hole. A feed-forward backpropagation neural network (FFBPNN) was used for nullifying the variation in amplitude to enable an accurate assessment of tool wear. This model utilised the normalised data achieved through normalisation of the amplitude variation factor of the vibration signal and was validated against the test data. The accuracy of the result was found to be 99.9%. [ABSTRACT FROM AUTHOR]

Non-laminate composites find their paramountcy in large structures, ballistic applications, etc. However, literature about the hole making process in thick composites, non-laminate composites and that under different cooling methods (dry, external and internal) is scarce. Hence the present study examines how the different methods of cooling influence the quality characteristics (drill flank temperature and damage factor) during drilling 20 mm thick Glass Fibre Reinforced Epoxy (GFRE) pultruded composite rods having 80% fibre weight fraction and 0° fibre orientations with reverence to the feed direction. Response Surface Methodology (RSM) was used to design the drilling experiments and the latter was executed utilizing 10 mm diameter twist drills made of cemented carbide. Response surface models utilizing Design-Expert software were developed, which empirically relates the process parameters with the obtained experimental values of quality characteristics. The effects caused by process parameters on quality characteristics were analyzed by utilizing response surface graphs. The process parameters (spindle speed, feed per revolution and coolant pressure) have been optimized within the selected range. The optimal parameter levels are attested by validation test. The contribution of this investigation is to make understand that the use of twist drill with internal cooling is critical to get damage tolerance holes. [ABSTRACT FROM AUTHOR]

Non-laminated composites find application in construction of bridges, ballistic applications, etc. However, literature on the drilling of non-laminated composite materials and literature on the drilling of thick composite materials under different cooling methods (dry, external and internal) is scarce. Hence the present study is aimed to investigate the influence of different cooling methods on quality characteristics (drill temperature and damage factor) while drilling glass fibre reinforced epoxy (GFRE) non-laminated 20 mm thick pultruded composite rods having 80% fibre weight fraction and 0° fibre orientations with respect to the drill. The drilling experiments using TiN/TiAlN coated tungsten carbide twist drills of diameter 10 mm were conducted using response surface methodology (RSM). The experimental values obtained for quality characteristics are empirically related to process parameters by developing a response surface model using Design-Expert software. The effects of process parameters on quality characteristics were analysed by using response surface graphs. The process parameters (feed, spindle speed and coolant pressure) are also optimized within the selected range. The optimal parameter levels are confirmed by validation test. From this investigation, it is evident that the internal cooling method is significant for obtaining high hole quality. [ABSTRACT FROM AUTHOR]

Glass fiber-reinforced polymers (GFRPs) are a unique class of materials in machining because unlike metals, they are not homogeneous. Given the inhomogeneous and anisotropic nature of composite materials, their machining behavior differs in many respects from that of metal machining. With metallic materials, the cutting force is uniform during drilling. Given GFRPs, drill bits are subject to variable cutting forces, whose responses to machining vary significantly. During GFRP drilling, heavy vibration is undesirable and results in rapid tool wear. The cutting condition can be controlled effectively to avoid heavy vibration by applying the appropriate cutting parameters. Hence, the most suitable cutting condition must be selected for proper process control. This study investigates the influence of vibration as a result of changes in cutting condition, drill diameter, and the number of holes. This influence is continuously monitored by the vibration signals generated during GFRP drilling with a TiN/TiALN-coated carbide drill bit. Experiments were conducted on a computer numerical control milling machine. The input parameters used for various cutting conditions were spindle speed and feed. The vibration signal was measured with an accelerometer, and its fluctuations were examined by a non-linear technique called recurrence quantification analysis (RQA). The influence of these fluctuations on vibration and their effect on tool life were also determined using RQA parameters. These parameters include percent recurrence, percent determinism, and percent laminarity. They have been used to study the effect of continuous fluctuations in vibration signals during drilling. This study confirmed that the RQA technique has potential for use in the investigation of a dynamical system. [ABSTRACT FROM AUTHOR]

Drilling of composite materials is difficult to carry out due to their anisotropic and non-homogenous structure and the high abrasiveness of their reinforced constituent. This results in high temperature during drilling, leading to rapid wear development in the cutting tool. The present work investigates the drilling of glass fibre-reinforced polymer composites with TiN/TiAlN-coated carbide drills on a computer numerical control (CNC) lathe for different cooling conditions. The objective of this work is to study the influence of different cooling conditions on drill bit temperature and drill bit wear. The signal to noise (S/N) ratio and analysis of variance (ANOVA) were employed to analyse the effect of cooling condition on drilling parameters. A linear polynomial model was developed using multiple regression analysis between drilling parameters and cooling condition with the drill bit temperature to represent the fitness characteristics. The workpiece made of GFRP is machined, and temperature is monitored during dry drilling, internal coolant and external coolant. The temperature of drill bit was measured by PFA Teflon-coated K (Chromega-Alomega) type thermocouples. From the analysis, it is evident that a linear multiple regression models developed to relate the cutting temperature with drilling parameters are with a minimum error of ±7 %. Internal coolant method reduces the average temperature by 76 % compared with dry drilling and 66 % compared with external coolant method. The reduction in tool temperature reduces the flank wear and increases the tool life by 43.75 % compared with dry drilling and 25 % compared with external coolant method. [ABSTRACT FROM AUTHOR]

In industrial applications, particularly in aero, marine and medical industries, titanium has received great attention as a useful material and electrical discharge machining as its machining process. Selection of optimal machining parameters in a multi-objective environment is essential for specific workpiece and tool material combination, which is the concern of industries to improve the overall productivity at less cost. In this article, optimization of critical electrical discharge machining parameters such as pulse current, on time of pulse, off time of pulse and tool geometry depending on the responses such as titanium machining rate, graphite wear rate, surface roughness and deviation between entry and exit while machining titanium grade 5 alloy with graphite tool electrode at negative polarity is presented. Taguchi’s L27 orthogonal array was used to design the experiment with interaction between factors. The weighing method was used to integrate different objectives into one performance. The optimal combination of process parameters was found statistically using signal-to-noise ratios. Significance was checked by analysis of variance. Optimum parameters were found to be pulse current 15 A, on time of pulse 50 µs, off time of pulse 200 µs and cylindrical tool geometry. Resultant percentage improvements in different responses were presented. [ABSTRACT FROM PUBLISHER]