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In this work, an ascendable low power 64-bit priority encoder is designed using a two-directional array to three-directional array conversion, and Split-logic technique and 6-bit is obtained as the output. By using this method, the high performance priority encoder can be achieved. In the conventional priority encoder, a single bit is set as an input, but for a priority encoder with 3-Darray, every input are specified in the matrix form. The I-bit input file is split hooked on M × N bits, similar to 2-D Matrix. In priority encoder with 3-Darray, three directional output comes out, unlike traditional priority encoder, where the output is received from one direction. The development can be achieved by implementing the two-directional array to three-directional array technique. Simulation results show that the proposed 2-D and 3-D priority encoder consumes 0.087039mW and 0.184014mW which is less when compared with the conventional priority encoder. The priority encoders are simulated and synthesized using VHDL in Xilinx Vivado version 2019.2 and the Oasys synthesis tool.

In turning process, tribological properties is a significant factor that affects production in the manufacturing sector. In the present study, particle damper is used to enhance the tribological properties during turning process. A particle damper is offered by means of particle which dissipate energy through friction and inelastic collisions. A particle damper with variable material, size, and filling in a turning tool is fabricated in this work. A 27 run experiments were conducted to find the effect of particle damping on tribological properties during the turning process. The particle in the turning tool will collide with one another and increases the rigidity of the tool holder which enhances the tribological properties. The experimental results, S/N ratio and ANOVA analysis shows that when stainless steel particle is partially filled with smaller size achieve enhance tribological properties. The results were compared without particle damper and found the particle damper reduce surface roughness and tool wear effectively.

Purpose In parallel sampling method, the size of the sampling capacitor is reduced to improve the bandwidth of the ADC. Design/methodology/approach Various low-power techniques for 10-bit 200MS/s pipelined analog-to-digital converter (ADC) are presented. This work comprises two techniques including parallel sampling and switched op-amp sharing technique. Findings This paper aims to study the effect of parallel sampling and switched op-amp sharing techniques on power consumption in pipelined ADC. In switched op-amp sharing technique, the numbers of op-amps used in the stages are reduced. Because of the reduction in the size of capacitors in parallel sampling technique and op-amps in the switched op-amp sharing technique, the power consumption of the proposed pipelined ADC is reduced to a greater extent. Originality/value Simulated the 10-bit 200MS/s pipelined ADC with complementary metal oxide semiconductor process and the simulation results shows a maximum differential non-linearity of +0.31/−0.31 LSB and the maximum integral non-linearity (of +0.74/−0.74 LSB with 62.9 dB SFDR, 55.90 dB SNDR and ENOB of 8.99 bits, respectively, for 18mW power consumption with the supply voltage of 1.8 V.

In metal cutting, tool vibration is a significant parameter, which results in high cutting force, increase in tool wear and poor surface quality of the finished product. To control tool vibration, an innovative and a robust damper was required. In this regard, a magnetorheological elastomer was fabricated, and the effect of parameters like the ratio of iron particles to elastomer; plunger shape and intensity of current were studied. Cutting experiments were conducted to arrive at an optimum set of parameters, which can suppress tool vibration during turning of hardened SS410 steel. From the experimental results, it was observed that the use of magnetorheological elastomer has reduced the tool vibration by 60% and also improved the cutting performance significantly.

In boring operations, tool vibration is a significant parameter which leads to poor surface finish, tool wear and damage of cutting tool. The relative dynamic motion between the cutting tool and work material induces vibration which accelerates tool wear, damage surface finish and produce irritating noise. In order to restrain tool vibration in metal cutting, it is necessary to develop and analyze suitable method which increases stability thereby improving cutting performance. The present investigation aims at developing a smart material controlled boring bar which will respond to an applied field with a dramatic change in rheological behavior. Magnetorheological fluid which was controlled by size of the particle, viscosity of fluid and positioning of rheological fluid is used as smart material in this paper. Magnetorheological fluid was developed and cutting experiments were conducted to arrive at a set of parameters that can reduce tool vibration and promote better cutting performance during boring of hardened AISI 4340 steel. From the results, it was observed that smart material controlled boring bar reduces tool vibration and also improves the cutting performance.

Purpose A new cutting tool is always well-defined and sharp at the onset of the metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of the service period of the cutting tool while machining. It is significant to provide a corresponding real-time varying damping to control this chatter, which directly influences accuracy and quality of productivity. This paper aims to review the literature related to the application of smart fluid to control vibration in metal cutting and also focused on the challenges involved in the implementation of active control system during machining process. Design/methodology/approach Smart dampers, which are used as semi-active and active dampers in metal cutting, were reviewed and the research studies carried out in the field of the magnetorheological (MR) damper were concentrated. In smart materials, MR fluids possess some disadvantages because of their sedimentation of iron particles, leakage and slow response time. To overcome these drawbacks, new MR materials such as MR foam, MR elastomers, MR gels and MR plastomers have been recommended and suggested. This review intents to throw light into available literature which exclusively deals with controlling chatter in metal cutting with the help of MR damping methods. Findings Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration. In the past, many researchers have attempted to implement MR damper in metal cutting to control vibration and were successful. Various methods with the help of MR fluid are illustrated. Research limitations/implications A new cutting tool is always well-defined and sharp at the onset of metal cutting process and gradually losses these properties as the machining process advances. Similarly, at the beginning of the machining process, amplitude of tool vibrations is considerably low and it increases gradually and peaks at the end of service period of cutting tool while machining. Application of MR damper along with the working methodology in metal cutting is presented, challenges met are analyzed and a scope for development is reviewed. Practical implications This study provides corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity. Using an MR damper popularly known for its semi-active damping characteristics is very adaptable and flexible in controlling chatter by providing damping to real-time amplitudes of tool vibration. Social implications This study attempts to implement smart damper in metal cutting to control vibrations. Originality/value It is significant to provide corresponding real-time varying damping to control tool vibration which directly influences accuracy and quality of productivity.

In boring operations, tool vibration is an important factor that affects the production in the manufacturing sector, due to its much overhanging length. An attempt is made to suppress tool vibration effectively by means of a particle damper. A particle damper is offered through particle which dissipates energy through friction and inelastic collisions. A particle damper with variable material, size, and filling in a boring tool is fabricated in this work. A 27 run experiment were conducted to find the effect of particle damping on tool vibration during the boring process. The results were compared without particle damper and found the particle damper suppress tool vibration and cutting force effectively. The particle in the boring tool will collide with one another and increases the rigidity of the tool holder which enhances the cutting parameters.

In boring process, due to rise in temperature at cutting zone, the tool is subjected to excess wear, which also affects the production rate, product quality and economy rate. A multilayer coated tools as a positive approach towards the tribology property such as tool wear, especially at high cutting velocities. In the present investigation, the boring tool is coated with varied oxides such as aluminium, titanium and zirconium using spray, spin and dip coating technique and cutting experiments were conducted on wet, semisolid and dry condition. A 27 run cutting experiments were conducted based on the taguchi technique and it was found that titanium and zirconium oxides with spray coating and wet condition afford promising results.

Tool vibration is a major issue in boring process because of its overhanging length which affects its tribological properties. A suitable mechanism can reduce tool vibration and increase the tribological properties. In present investigation, a stainless steel impact damper on boring tool is developed and experiments were conducted to reduce tool vibration and improve tribological properties. The results were analyzed using signal to noise ratio method and it shows that stainless steel spheres in boring tool suppress tool vibration and enhance the tribological properties efficiently when it is compared with conventional boring tool.

Purpose In the internal turning process, tool life and work piece quality are greatly influenced by the generation of heat in the cutting zone. During machining, cutting fluids are applied at the cutting zones to reduce heat generation and enhance tribological properties. However, in the boring process, cutting fluids cannot be applied at cutting zone properly, and wastage of cutting fluid is a threat to the ecology and personnel health. Hence, application of semisolid lubricant in the boring process is considered as an innovative technique for temperature reduction in cutting zone because of its eco-friendly system, which also has a higher ability of biodegradability. This paper aims to study the influence of semisolid lubricants comprising of grease,graphite, aluminium oxide in different composition applied at a tool–chip,tool–work interface using a semisolid lubricant applicator applied with varying pressure. Design/methodology/approach In the present study, the cutting performance during boring of AISI4340 steel is enhanced through the application of semisolid lubricant with different composition of grease, graphite and aluminium oxide applied at tool-work and tool-chip interface with varying pressure using semisolid lubricant applicator. Findings The results show that use of semisolid lubricant like grease, graphite and nano aluminium oxide at tool-chip interface with maximum pressure reduces cutting temperature, tool vibration, cutting force and surface roughness. Originality/value Reduce cutting temperature, tool vibration, cutting force and surface roughness.

In manufacture sector, the surface finish quality has considerable importance that can affect the functioning of a component, and possibly its cost. The surface quality is an significant parameter to evaluate the productivity of machine tools as well as machined components. It is also used as the critical quality indicator for the machined surface. In recent years the prediction of surface roughness has become an area of interest for machining industry. Cutting force, cutting temperature, tool wear, and vibration signals are some of the factors that can be used individually to predict surface roughness, but when it is used collectively a more accurate prediction of surface roughness is possible since each of the above-mentioned factors have their own characteristics effects of surface roughness. In the present study, an attempt was made to fuse cutting force, tool wear and displacement of tool vibration along with the cutting speed, feed and depth of cut to predict the surface roughness of hardened SS 410 steel (45 HRC) using a multicoated hard metal insert with a sculptured rake face. Regression models and an artificial neural network model were developed to fuse the cutting force, cutting temperature, tool wear and displacement of tool vibration to predict the surface roughness. From the results it was observed that the prediction of surface roughness by the artificial neural network had a higher accuracy than the regression model.

Purpose The purpose of this work is to reduce the power consumption of KSA and to improve the PDP for data path applications. In digital Very Large – Scale Integration systems, the addition of two numbers is one of the essential functions. This arithmetic function is used in the modern digital signal processors and microprocessors. The operating speed of these processors depends on the computation of the arithmetic function. The speed computation block for most of the datapath elements was adders. In this paper, the Kogge–Stone adder (KSA) is designed using XOR, AND and proposed OR gates. The proposed OR gate has less power consumption due to the less number of transistors. In arithmetic logic circuit power, delay and power delay products (PDP) are considered as the important parameters. The delays reported for the proposed OR gate are less when compared with the conventional Complementary Metal Oxide Semiconductor (CMOS) OR gate and pre-existing logic styles. The proposed circuits are optimized in terms of power, delay and PDP. To analyze the performance of KSA, extensive Cadence Virtuoso simulations are used. From the simulation results based on 45 nm CMOS process, it was observed that the proposed design has obtained 688.3 nW of power consumption, 0.81 ns of delay and 0.55 fJ of PDP at 1.1 V. Design/methodology/approach In this paper, a new circuit for OR gate is proposed. The KSA is designed using XOR, AND and proposed OR gates. Findings The proposed OR gate has less power consumption due to the less number of transistors. The delays reported for the proposed OR gate are less when compared with the conventional CMOS OR gate and pre-existing logic styles. The proposed circuits are optimized in terms of power, delay and PDP. Originality/value In arithmetic logic circuit power, delay and PDP are considered as the important parameters. In this paper, a new circuit for OR gate is proposed. The power consumption of the designed KSA using the proposed OR gate is very less when compared with the conventional KSA. Simulation results show that the performance of the proposed KSA are improved and suitable for high speed applications.

Nowadays, the metal cutting industry is focussed on high production rate, better quality and good economic rate. In the boring process, the tool holder is subjected to excessive cutting force and surface roughness which affects the finished product. This can be avoided by using Multilayer Nano metal oxide coated tools which has a positive impact in improving cutting performance and coating was done in tool insert by dip, spin and spray technique for dry, semisolid and wet condition. In this paper, Aluminium oxide + zirconium oxide, titanium oxide + zirconium oxide and zirconium oxide were used as coating material. A 27 run cutting experiment was designed and cutting force and surface roughness was measured. Experimental results were optimized using Taguchi technique and from the results it was observed that two layered TiO2 +ZrO2 deposited in series provide a better cutting enactment against the Al2O3 +ZrO2 and ZrO2

In boring process, tool vibration is an important parameter which results in progressive tool wear, poor surface finish and cutting tool damage. This tool vibration was reduced by passive, semi-active and active techniques which are used by various researchers in the past. In this paper, various techniques employed to prevent tool vibration in boring operation are reviewed, analyzed and presented. It was inferred that the control of tool vibration was effective by utilizing appropriate damping mechanism in the boring process. Also, from the overall review of the literature, it was observed that as the tool wear started to progress, the tool vibration gets increased which leads to failure of the tool. In this review paper, scope of developing a damper where tool vibration can be suppressed by varying the damping ability based on requirement was established.

During boring process, tool vibration is a major concern due to its overhanging length, which results in high cutting force, poor surface finish, and increase in tool wear. To suppress tool vibration and improve cutting performance, a novel technique in rheological fluid was designed and developed. In this work, a magnetorheological elastomer (MRE) was developed, and parameters, such as piston location, current intensity, and coil winding direction, were considered. Cutting experiments were conducted to obtain a set of parameters that can efficiently control vibration during boring of hardened AISI 4340 steel. Taguchi method was used to optimize the cutting condition, and findings show that the cutting tool embedded with the MRE reduced tool vibration and effectively increased cutting performance.

Tool vibration is a dynamic instability of cutting process, which is a result of interaction between metal-cutting process and dynamics of machined tool. In metal-cutting process, the presence of t...

This work presents a low power 10-bit 40 MSPS Pipelined ADC with 1.8V supply voltage in a 180nm silicon based CMOS process. Simultaneous capacitor sharing and op-amp sharing technique is used between two successive stages of a Sample-and Hold Ampifier (SHA) to reduce the power consumption.The memory effect in the proposed ADC is eliminated by a low input capacitance variable gm op-amp. The differential and integral nonlinearity of the converter are within LSB.Simulation results show that the required Signal-Furious-Dynamic range (SFDR) of 70dB, Signal-to -Noise-plus Distortion Ratio (SNDR) of 56.1dB and 9.02 Effective Number of Bits ( ENOB ) has been achieved with a 2MHz, 1-Vp−p,diff input signal while consuming only 7.3mW power from 1.8V supply.

Based on the 0.18 $\mu$ m 1.8V CMOS process, a novel architecture of folded cascode operational transconductance amplifier (OTA) is designed for a 10-bit pipelined A/D converter. Folded cascode OTA is the basic block of pipelined ADCs. Folded cascode OTA has a stable transient output of 1.6V. Simulation results show that the open-loop gain of the folded cascode OTA is 42.78 dB, Common-mode Rejection Ratio(CMRR) is 43.11 dB, the phase margin is 1330, and slew rate of 105.657V / $\mu$ s respectively. The power consumption of this amplifier is 13.64 $\mu$ W in the 180nm CMOS process. The simulated output waveform and frequency response is shown for a supply voltage of 1.8V.

During machining process, tool holder is subjected to vibration, which has considerable influence on productivity and quality of the product. In order to control displacement and provide stability during machining, mass damper was developed in the present investigation. The mass damper used in this paper consists of a specific auxiliary mass attached to the tool shank at a definite location. The size and shape of the auxiliary mass were designed using arithmetic analysis, and the mounting position of the mass on the tool shank was determined using computational analysis. When the auxiliary mass was mounted on the tool holder, the rigidity of the tool holder got enhanced and provides an inherent damping ability to the tool holder for controlling tool vibration. From the computational results, it was observed that the use of auxiliary mass collision on tool holder reduces displacement in cutting tool considerably.

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.

In the boring process, the tool is subjected to excessive wear due to an increase in cutting temperature which affects the quality of the finished product. To avoid the rise in cutting temperature multilayer-coated tools were used to improve machining performance. In this present investigation, Aluminum oxide+zirconium oxide, titanium oxide+zirconium oxide and zirconium oxide were used as coating material with various coating techniques such as dip, spin and spray for dry, semisolid and wet condition. A 27 run experimental results were optimized using the Taguchi technique and analysis of variance and found that two-layered TiO2 +ZrO2 deposited in series gives a better performance against the Al2O3 +ZrO2 and ZrO2 with spray technique and wet condition.

Vibrations are an inherent phenomenon in rotating machineries. They are present in all types of machines and mechanical components. They are unwanted because they affect the optimal performance of these components and hence, it needs to be eliminated. Amongst the different parameters that affect vibration, selection of appropriate material is the most critical parameter. In this research paper, the effect due to the use of different types of shaft materials on vibration in rotating machinery is studied and the magnitude of vibration produced due to the use of different type of shaft material under the same condition of loads and rotational speeds was investigated. Shaft materials considered in this paper were stainless steel and mild steel and these materials were tested for Ball Bearing, Thrust Bearing and Tapered Roller Bearing. From experimental result, it was observed that mild steel gives the high amplitude of vibration for all the three bearings. Hence, it is preferable to use Stainless Steel than Mild Steel in rotational machineries due to its physical properties and lower vibration amplitude in varied conditions.

This review of MRF (magnetorheological fluids or MR fluids) brings out the challenges in methods of preparation, difficulties encountered in storage and use, and possible solutions to overcome the challenges.Magnetorheological fluid in the rheological fluid domain has found use due to its ability to change its shear strength based on the applied magnetic field. Magnetorheological fluids are composed of magnetizable micron-sized iron particles and a non-magnetizable base or carrier fluid along with additives to counter sedimentation and agglomeration.Magnetorheological fluids can respond to external stimuli by undergoing changes in physical properties thus enabling several improved modifications in the existing technology enhancing their application versatility and utility. Thus, magnetorheological fluid, a rheological material whose viscosity undergoes apparent changes on application of magnetic field, is considered as a smart material. Such materials can be used for active and semi-active control of engineering systems.Many studies on the designs of systems incorporating MR fluids, mainly for vibration control and also for other applications including brakes, clutches, dynamometers, aircraft landing gears, and helicopter lag dampers, have emerged over last couple of decades. However, the preparation as well as the maintenance of magnetorheological fluids involves several challenges. Sedimentation is a major challenge, even when stored for moderate periods of time. A comprehensive review is made on the problems confronted in the preparation of magnetorheological fluids as well as sustenance of the properties, for use, over a long period of time. Other problems encountered include agglomeration and in-use thickening (IUT) as well as rusting and crusting. Of interest is the mitigation of these problems so as to prepare fluids with satisfactory properties, and such solutions are reviewed here. The control of magnetorheological fluids and the applications of interest are also reviewed.The review covers additives for overcoming challenges in the preparation and use of magnetorheological fluids that include incrustation, sedimentation, agglomeration, and also oxidation of the particles. The methodology to prepare the fluid along with the process for adding selected additives was reviewed. The results showed an improvement in the reduction of sedimentation and other problems decreasing comparatively. A set of additives for addressing the specific challenges has been summarized. Experiments were carried out to establish the sedimentation rates for compositions with varying fractions of additives.The review also analyzes briefly the gaps in studies on MR fluids and covers present developments and future application areas such as haptic devices.

In this paper design of low power 4-bit Flash ADC for high frequency applications is presented. The power consumption of the Flash ADC in this work has been reduced in two phase. In the first phase a low power dynamic comparator has been designed which consumes 329.332 µW power. In the second phase a low power Fat tree encoder has been designed. The proposed encoder design uses reduced number of gates than the conventional design. As a result the average power dissipation of the encoder block is 43.6µw. The above mentioned Flash ADC is designed using CMOS 90nm Technology in Cadence tool. The proposed design has a power consumption of 5.1096 mW at IV power supply and at a sampling frequency of 1GHz.

In low-power VLSI design applications non-linearity and harmonics are a major dominant factor which affects the performance of the ADC. To avoid this, the new architecture of voltage-controlled oscillator (VCO) was required to solve the non-linearity issues and harmonic distortion. In this work, a 12-bit, 200MS/s low power delta-sigma analog to digital converter (ADC) VCO based quantizer was designed using switched capacitor technique. The proposed technique uses frequency to current conversion technique as a linearization method to reduce the non-linearity issue. Simulation result show that the proposed 12-bit delta-sigma ADC consumes the power of 2.68 mW and a total area of 0.09 mm² in 90 nm CMOS process.

Magnetorheological (MR) fluid damper which allows the damping characteristics of the damper to be continuously controlled by varying the magnetic field is extensively used in metal cutting to suppress tool vibration. Even though magnetorhelogical fluids have been successful in reducing tool vibration, durability of magnetorhelogical fluids remains a major challenge in engineering sector. Temperature effect on the performance of magnetorhelogical fluids over a prolonged period of time is a major concern. In this paper, an attempt was made to reduce temperature and to improve viscosity of magnetorhelogical fluids by infusing nanoparticles along with MR fluids. Aluminium oxide and titanium oxide nanoparticles of 0.1% and 0.2% concentration by weight were considered and experimental tests were conducted to study the influence of nanoparticles on the performance of magnetorheological fluid. From the experimental results it was observed that the presence of nanoparticles in MR fluid reduces temperature and increases the viscosity of MR fluid thereby increasing the cutting performance during turning of hardened AISI 4340 steel.