Informatics Publishing Limited

Musalimadugu Kartheek ¹, M. Girish Kumar ², A. Ananda Babu ³

Affiliations
1 CAD/CAM, VIT University, Tamilnadu, IN
2 Noise and Vibration Laboratory, Central Manufacturing Technology Institute (CMTI), Bangalore, Karnataka, IN
3 SMBS, VIT University, Tamilnadu, IN

Abstract

Surface quality is the most significant characteristic in the manufacturing industry for components produced by any of the machining processes which is indicated by surface roughness. Surface roughness is mainly affected by cutting parameters, machine tool vibrations and tool geometry. In this work efforts have been made to acquire vibration data on spindle housing of a vertical milling center while machining by kistler tri-axial accelerometer using Data Physics eight channel analyzer with recording option, measure surface finish and analyze the influence of cutting parameters on machine tool vibration and surface finish using ANOVA in MINITAB for the designed experiments using Taguchi method. Later the vibration signals are imported into MATLAB. Wavelet toolbox is used for further identification of numerically quoted fault frequencies of the machine tool from the signals one by one using a new method based on wavelet packet transform to find the peak to peak amplitudes of the signals. Further these cutting parameters with the amplitudes are used for the prediction of surface roughness using ANN. The cutting parameters are then optimized, which are being sent to CNC machine to improve the surface roughness and control vibration. This work will provide an engineer who designs a machining center with a tool to predict the vibrations and also provide a guideline for industrial engineers.

Keywords

Vibration signals, Wavelet Packet Transform, Artificial Neural Networks (ANN) and Genetic Algorithm (GA) etc.

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M. Girish Kumar ¹, Prakash Vinod ¹, P. V. Shashikumar ¹

Affiliations
1 Nano Manufacturing Technology Centre, Central Manufacturing Technology Institute, Bangalore, IN

Abstract

Nanotechnology deals with particles and system with dimensions of approximately 1 to 100 nanometers. The environment factors like ground vibration, temperature, humidity, acoustics, air velocity, Electro Magnetic Interference, Illumination and cleanliness will limit the performance of equipments used in nano manufacturing. Among all the environmental factors, ground vibration plays a major role in limiting the performance of the equipment. Some aspects of nanomanufacturing facilities like nanofabrication, nanometrology requires extremely stable environment with very stringent limits of ground vibration. This paper is focused on the study of vibrations induced by metro train movement. The study reveals that, the vibration induced by metro train is exceeding the limits as per the standard set by the National Institute of Standards and Technology (NIST).

Keywords

Vibration, Rail, Nano Metrology, Nanotechnology, Nanomanufacturing.

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Prakash Vinod ¹, M. Girish Kumar ¹, P. V. Shashikumar ¹

Affiliations
1 Nano Manufacturing Technology Centre, CMTI, Bangalore, IN

Abstract

Nanometrology deals with measurements and analysis of dimensions of approximately 1 to 100 nanometres as well as measurement of force, electrical, magnetic and optical properties and to correlate the measured size with properties. Some aspects of this work require extremely stable environments. Very stringent limits are often required on environmental vibration and noise, temperature, EMC, Illumination and Clean Room requirements. The environmental requirements of Nanometrology from the perspective of designing of an advanced Nanometrology laboratory are studied and reviewed in this paper. A desirable environment at a site may be adversely affected by ground vibration from a variety of sources such as road traffic, metro train movements, utility plants and the construction. The environment inside the lab is also affected by temperature fluctuation, humidity, acoustics disturbances, air velocity, EMC, Illumination and cleanliness. All these factors affect the nano level measurements. This paper addresses various environmental conditions, its potential effect on nano level measurements and environmental conditions to be maintained for a nano metrology laboratory.

Keywords

Ground Vibration, Nano Metrology, Noise, Temperature, Humidity, Metro Train, EMI/EMC, Airflow, Cleanroom, Vibration Isolation.

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Prakash Vinod ¹, J. Ramachandra Kiran ¹, M. Girish Kumar ¹, P. V. Shashikumar ¹

Affiliations
1 Micro Engineering and Nano Technology Dept, Central Manufacturing Technology Institute, Bangalore, IN

Abstract

Nanometrology deals with measurements and analysis of dimensions of approximately 1 to 100 nanometres. Some aspects of this work require extremely stable environments. Very stringent limits are often required on environmental vibration and noise, temperature, EMC, Illumination and Clean Room requirements. The environmental requirements of Nanometrology from the perspective of designing of an advanced Nanometrology laboratory are studied and reviewed in this paper. A desirable environment at a site may be adversely affected by ground vibration from a variety of sources such as vehicle traffic, rail, utility plants and the construction. The environment inside the lab may be also affected by temperature fluctuation, humidity, acoustics disturbances, air velocity, EMC, Illumination and cleanliness. All these factors affect the nano level measurements. This paper addresses various environmental conditions to be maintained for establishment of a nano metrology laboratory and its potential impact on nano level measurements.

Keywords

Nano Metrology, Vibration, Noise, Temperature, Humidity, Traffic, Rail.

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M. Girish Kumar ¹, Prakash Vinod ¹, P. V. Shashikumar ¹

Affiliations
1 MNT Dept., CMTI, Bangalore, IN

Abstract

Unbalance in rotating machinery is a common source of vibration in many applications and has a strong impact on the performance, accuracy of product and life of the rotating system. Generally, the dynamic balancing of rotors are carried out with the help of FFT Analyzer with expensive balancing software. Most of the commercially available balancing programs are not flexible, requires input like exact location o f the trial mass with respect to reference mark and do notallow intervention in between balancing procedure and in case of any mistake, the entire procedure need to be repeated. There are other methods for dynamic balancing like graphical method and trial and error method is cumbersome and prone to errors. This paper gives details on the development of an analytical method for dynamic balancing, which can be used with normal FFT Analyzer (with amplitude and Phase information). This method is inexpensive, easy to use, flexible and requires less time. This method provides correction mass and its angle with respect to the trial mass position. The developed analytical method has been validated by graphical method, experimental data and practical cases.

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