1. A
Project Report
On
ASSOCIATION OF DAQ SYSTEM IN CNC MACHINE
FOR MICRO MILLING PROCESS
Submitted in Partial Fulfilment of the Required for the Award of Degree in
Bachelor of Technology
In
Mechanical Engineering
By
Shubham Agrawal (12119077)
Rohit Nath (12119046)
Sumit Kumar (11119081)
Ankit Ojha (11119009)
Niteesh Ram (09119045)
Approved By: Guided By:
Dr. R Salhotra Dr. M. S. Rajput
[Head of Department] [Assistant Professor]
Department of Mechanical Engineering
National Institute of Technology Raipur
2012-2016

2. 2
ACKNOWLEDGEMENT
With great pleasure, we hereby extend our heartiest thanks and deep sense of
indebtedness to Dr.Mridul Singh Rajput , Mechanical Engineering
Department, NIT Raipur; for his guidance and everlasting help which has been
instrumental in completion of this work. It would never be possible for us to
take this project to this level without his innovative ideas and his relentless
support and encouragement.
Our heartiest thanks to Dr. Rahul Salhotra, Head of Mechanical Engineering
Department, NIT Raipur, for his constant encouragement without which we
couldn’t have carried out this project in time.
Further we are also grateful to all our professors of Mechanical Engineering
Department for their teaching, which has helped us at every stage of the
project work.
Shubham Agrawal (12119077)
Rohit Nath (12119046)
Sumit Kumar (11119081)
Ankit Ojha (11119009)
Niteesh Ram (09119045)

3. 3
CERTIFICATE
This is to certify that minor project report entitled “ASSOCIATION OF DAQ
SYSTEM IN CNC MACHINE FOR MICRO MILLING PROCESS” submitted, by Rohit
Nath (12119046), Shubham Agrawal (12119077), Sumit kumar (11119081),
Ankit Ojha (11119009), Niteesh Ram (09119045), in partial fulfilment of the
requirement of the degree of the Bachelor of Technology in Mechanical
Engineering at the National Institute of Technology, Raipur, during the
academic year 2015-2016 is a bona-fide record of work carried out under my
guidance and supervision. This certification does not necessarily endorse or
accept any statement made opinion expressed or conclusion drawn as
recorded in this report. However it only signifies the acceptance of report for
the purpose of which it is submitted.
Dr. Mridul Singh Rajput Dr. Rahul Salhotra
Assistant Professor Head of Department
Mechanical Engineering Mechanical Engineering

4. 4
INDEX
TITLE PAGE NO
Introduction 5
Literature Review 6
Problem Identification 9
Experimental Setup 10
Experimental Process 19
Outcome 22
Conclusion 25

5. 5
Introduction
Any object you see around yourself goes through rigorous machining process
such as milling, cutting, edging, fabrication etc. Milling process occupies a very
important role in getting the desired final outcome. Milling is the most common
form of machining, a material removal process, which can create a variety of
features on a part by cutting away the unwanted material.
Milling is a cutting process that uses a milling cutter to remove material from
the surface of a workpiece. The milling cutter is a rotary cutting tool, often with
multiple cutting points. As opposed to drilling, where the tool is advanced along
its rotation axis, the cutter in milling is usually moved perpendicular to its axis
so that cutting occurs on the circumference of the cutter. As the milling cutter
enters the workpiece, the cutting edges (flutes or teeth) of the tool repeatedly cut
into and exit from the material, shaving off chips (swarf) from the workpiece
with each pass.
Milling is typically used to produce parts that are not axially symmetric and
have many features, such as holes, slots, pockets, and even three dimensional
surface contours. Parts that are fabricated completely through milling often
include components that are used in limited quantities, perhaps for prototypes,
such as custom designed fasteners or brackets. Another application of milling is
the fabrication of tooling for other processes.
Copper & Its Machining
Copper is a soft, malleable and ductile metal with very high thermal and
electrical conductivity. A freshly exposed surface of pure copper has a reddish-
orange colour. It is used as a conductor of heat and electricity, as a building
material, and as a constituent of various metal alloys. It has Young’s Modulus
of 110-128 Gpa & Brinell Hardness of 235-878 Mpa.

6. 6
What Is Data Acquisition?
Data acquisition (DAQ) is the process of measuring an electrical or physical
phenomenon such as voltage, current, temperature, pressure, or sound with a
computer. A DAQ system consists of sensors, DAQ measurement hardware,
and a computer with programmable software. Compared to traditional
measurement systems, PC-based DAQ systems exploit the processing power,
productivity, display, and connectivity capabilities of industry-standard
computers providing a more powerful, flexible, and cost-effective measurement
solution.
NI ELVIS 2 DAQ SYSTEM

7. 7
Literature Review
After making careful analysis of few journals and previous research papers on
Micro Milling & its characteristics, we have got an insight about the topic and
the following conclusion have been made.
Bang et al. ,has been given that micro stage, PC based control board and air
spindle can be used to produce a low cost milling machine. Various experiments
involving machining of micro blades, micro columns & micro walls shows the
capability of micro milling machine to produce micro parts.
Rahman et al. , Concluded that to identify the major causes affecting the tool
life various experiments have been done on pure Copper. On machining the
pure Cu both spiral and broken chips were formed. The size of the chip varies
but the shape remains same. There was a unique thing observed that the tool life
increases with the increase in depth of cut. There was an increase in tool when
the helix angle was kept 25 degrees. So the tool life depends on helix angle and
depth of cut.
Tansel et al. , stated that it was the experiment based on tool breakage
mechanisms in micro end milling operations. A relationship was found after the
experiment between tool condition and the static part of the feed direction
cutting force. Segmental averages and wavelet transformations were used for
tool breakage prediction. Fatigue and excessive load related micro tool breakage
was effected by usage related stress.
Chae et al. ,investigated on micro cutting operations ,benefits of use of
miniature parts for micro milling process. Smaller footprints, lower power
consumption & higher heat transfer are the benefits which are obtained by using
miniature components. Micro-mechanical machining is well suited to support
the development of micro-injection moulds because of its promise for accurate,
low cost, small batch size processes of 3D moulds using ferrous alloys.
Tansel et al. ,stated that it was an experiment which was performed to increase
the tool life by using a smart workpiece holder. In this, the cutting force was
monitored which reduce the metal removal rate. This was conducted on mild
steel & Aluminium work pieces. After using this smart work piece holder there
was 30% increase in tool life & 50% prediction of tool breakage possibilities.

8. 8
Tansel et al. , concluded that tool breakage & wear were determined by the use
of new methods namely Acoustic Emission signals, ART2 & AIM polynomial
network. In Acoustic emission signal method we interpret the digitalised
envelope of AE signals which were produced by analog circuit, we obtain a
final output signal after filtering the signal with a very narrow band pass filter.
The analog processing circuit also filtered the external noise & other
interferences.
To determine the wear the processed AE signals were encoded by using three
main parameters such as ART2 unsupervised neutral network & AIM
polynomial network.
Thepsonthi et al. ,stated in this experiment a simulation of real experiment was
conducted using a software to compare the values obtained with the ideal
values. The main parameters of consideration were cutting temperature, 3D
cutting forces & chip formation. 3D FE Models were used to find out the effect
of tool wear. The conclusion drawn were with the increase in negative rake
angle the tool wear increased.
Mijušković et al. ,stated in this experiment analytical & regression model was
developed for the analysis of tool deflection in micro milling of graphite
electrodes. From the above process depth of cut, width of cut & feed are the
important factor determining the tool deflection. It was observed that angle of
approach is directly proportional to maximum chip thickness.

9. 9
Problem Identification
• Lack in surface finish of Milled specimen
The conventional Milling process did not give us satisfactory outcome in terms
of surface finish. Surface roughness is broadly understood as a measurement of
by how much amplitude the surface departs from a mean and at what frequency
those departures are prone to occur. As per the previous experiments, the factors
that effect the surface finish was the lack of information about parameters such
as Force.
• Lack of required accuracy
While there are few significant disadvantages to the milling process, those that
are present can often be attributed to inaccuracies in a features dimensions.
Lack of accuracy leads to the wastage of raw material & time. This increases
the overall cost of the final output.
• Wearing of tool
The tool gets blunt and its life gets reduced after certain period of usage. This
was a major problem which effected the efficiency of tool. The increase in
temperature is the main cause of tool wearing which is directly proportional to
the force & friction between the tool & the job surface. The lack of feedback
parameter such as force was a major drawback in getting rid of this major
problem which at the end effects the final output.
• Lack of complete information from current feedback system
The current feedback system gives information only about position & velocity
lacking other parameters such as force etc. The lack of these information leads
to lack in surface finish & accuracy.

10. 10
Experimental Setup
1. SinuTrain Software
The methodology which we have chosen is briefed as following. We will be
gaining knowledge about the working of Computer Numerically Controlled
(CNC) Machine by the use of simulation software called as SinuTrain.
SinuTrain/JobShop is the automation system simulation CNC training software
on CD-ROM. It runs on a PC and is as suitable for training purposes and self-
study as it is for writing programs and simulation.
SinuTrain incorporates the functionality of the HMI Advanced operator
interface of the SINUMERIK 810D/840D and 840Di controls and is capable of
running on a standard PC under Windows OS. The software is supplemented by
services that are required to set up and operate a training centre. This modular
system as a whole represents a holistic approach to meeting the needs of those
involved in teaching and studying Computer Numerically Controlled
technology.
Figure 1 - SinuTrain Software

11. 11
By using the SinuTrain software we have got a keen insight about the working
Computer Numerically Controlled (CNC) Machine in a virtual platform. We
will do some experiments regarding process like milling and then moving to
micro milling process which will be useful in attaining micro features.
The experiments will be conducted to improve the surface finish & reduce tool
wear by changing
1. Tool speed
2. Feed Rate
3. Clear the chips
Snapshot of GUI in CNC Machine

12. 12
2. Cutting Tool
An end mill is a type of milling cutter, a cutting tool used in industrial milling
applications. It is distinguished from the drill bit in its application, geometry,
and manufacture. While a drill bit can only cut in the axial direction, a milling
bit can generally cut in all directions, though some cannot cut axially. End mills
(middle row in image) are those tools which have cutting teeth at one end, as
well as on the sides. The word end mill is generally used to refer to flat
bottomed cutters, but also include rounded cutters (referred to as ball nosed) and
radiused cutters (referred to as bull nose, or torus). They are usually made from
high speed steel or cemented carbide, and have one or more flutes. They are the
most common tool used in a vertical mill.
Snapshot of End Mill Cutting Tool

13. 13
The specification & image of the cutting tool used in the experiment is shown
below -
Diameter & Weight of the Cutting Tools

14. 14
3. Sensors
A sensor is an object whose purpose is to detect events or changes in its
environment, and then provide a corresponding output. A sensor is a type of
transducer; sensors may provide various types of output, but typically use
electrical or optical signals. For example, a thermocouple generates a known
voltage (the output) in response to its temperature (the environment). A
mercury-in-glass thermometer, similarly, converts measured temperature into
expansion and contraction of a liquid, which can be read on a calibrated glass
tube.
Sensors (NICTECH – CF – 120 – 2AA – (II) – C20 , 2mm , 120 ohm)

15. 15
4. Data Acquisition System
Data acquisition (DAQ) is the process of measuring an electrical or physical
phenomenon such as voltage, current, temperature, pressure, or sound with a
computer. A DAQ system consists of sensors, DAQ measurement hardware,
and a computer with programmable software. Compared to traditional
measurement systems, PC-based DAQ systems exploit the processing power,
productivity, display, and connectivity capabilities of industry-standard
computers providing a more powerful, flexible, and cost-effective measurement
solution.
DAQ System (NI ELVIS II)

16. 16
5. Tool Vice
It is a mechanical apparatus used to secure an object to allow work to be
performed on it. Vices have two parallel jaws, one fixed and the other movable,
threaded in and out by a screw and lever.
Vice device consisting of two parallel jaws for holding a workpiece; one of the
jaws is fixed and the other movable by a screw, a lever, or a cam. When used
for holding a workpiece during hand operations, such as filing, hammering, or
sawing, the vise may be permanently bolted to a bench. In vises designed to
hold metallic workpieces, the active faces of the jaws are hardened steel plates,
often removable, with serrations that grip the workpiece; to prevent damage to
soft parts, the permanent jaws can be covered with temporary jaws made from
sheet copper or leather. Pipe vises have double V-shaped jaws that grip in four
places instead of only two. Woodworking vises have smooth jaws, often of
wood, and rely on friction alone rather than on serrations.
For holding workpieces on the tables of machine tools, vises with smooth
hardened-steel jaws and flat bases are used. These machine vises are portable
but may be clamped to the machine table when in use; means may also be
provided for swivelling the active part of the vise so that the workpiece can be
held in a variety of positions relative to the base. For holding parts that cannot
be clamped with flat jaws, special jaws can be provided.
Vice

17. 17
6. Computer Numerically Controlled (CNC)
Numerical control (NC) is the automation of machine tools that are operated by
precisely programmed commands encoded on a storage medium, as opposed to
controlled manually by hand wheels or levers, or mechanically automated by
cams alone. Most NC today is computer (or computerized) numerical control
(CNC), in which computers play an integral part of the control.
In modern CNC systems, end-to-end component design is highly automated
using computer-aided design (CAD) and computer-aided manufacturing (CAM)
programs. The programs produce a computer file that is interpreted to extract
the commands needed to operate a particular machine by use of a post
processor, and then loaded into the CNC machines for production. Since any
particular component might require the use of a number of different tools –
drills, saws, etc., modern machines often combine multiple tools into a single
"cell". In other installations, a number of different machines are used with an
external controller and human or robotic operators that move the component
from machine to machine. In either case, the series of steps needed to produce
any part is highly automated and produces a part that closely matches the
original CAD design.
MTAB Milling CNC Machine

18. 18
6. Wheatstone Bridge
A Wheatstone bridge is an electrical circuit used to measure an unknown
electrical resistance by balancing two legs of a bridge circuit, one leg of which
includes the unknown component. The primary benefit of a wheatstone bridge is
its ability to provide extremely accurate measurements (in contrast with
something like a simple voltage divider). Its operation is similar to the original
potentiometer.
The Wheatstone bridge was invented by Samuel Hunter Christie in 1833 and
improved and popularized by Sir Charles Wheatstone in 1843. One of the
Wheatstone bridge's initial uses was for the purpose of soils analysis and
comparison.
Wheatstone Bridge

19. 19
Experimental Process
The main aim of our project is to improve the feedback system of CNC machine
by associating DAQ system. The steps taken during the experiment are:
1. Software Simulation.
2. Selection of Specimen & its material.
3. Pre Experimental Setup of Sensors, Wheatstone Bridge & Tool.
4. CNC Coding.
5. Associating DAQ System.
1. Software Simulation
Before trying our hands on real CNC Machine, we made our hands free by
doing simulation in software called ‘SinuTrain’. This helped us in getting a
brief idea about the working of CNC Machine in the virtual world. It was
helpful in getting a grip over the CNC’s GUI (Graphical User Interface)
software.
2. Selection of Specimen & its material
Since copper has a good machinable properties, we have selected it as our job
for performing micro milling. Copper is a soft, malleable and ductile metal with
very high thermal and electrical conductivity. It has Young’s Modulus of 110-
128 Gpa & Brinell Hardness of 235-878 Mpa.
Copper & Aluminium Specimens

20. 20
3. Pre Experimental Setup of Sensors, Wheatstone Bridge & Tool
In this project, the sensor used is NICTECH – CF – 120 – 2AA – (II) – C20
which has 2 mm of length & is of 120 Ohm. This sensor was attached to the
specimen in a specified manner as shown in the figure. There sensors are used
to calculate the force acting on the specimen in that direction.
Sensors attached in Copper Specimen
Tool holder is used to hold the tool in such a way that it doesn’t vibrate during
the milling operation. It gives support to the primary tool & helps in getting a
high quality finished job.

21. 21
In practice, strain measurements rarely involve quantities larger than a few
millistrain (e x 10^-3). Therefore, to measure the strain requires accurate
measurement of very small changes in resistance wheatstone bridge is used. For
example, suppose a test specimen undergoes a strain of 500 me. To measure
such small changes in resistance, strain gages are almost always used in a bridge
configuration with a voltage excitation source. Since the wheatstone bridge is
applicable only for a particular ratios of resistance we have set the resistors to
120 Ohm.
Setting resistance to 120 Ohm in Wheatstone Bridge
4. CNC Programming
CNC part program is a detailed list of instructions that need to be executed by
the Machine Control Unit to achieve the final component shape. The Machining
sequence needed to manufacture a given part is broken down into small
elements and written in a specific format understood by the MCU. Most NC
today is computer (or computerized) numerical control (CNC), in which
computers play an integral part of the control. In modern CNC systems, end-to-
end component design is highly automated using computer-aided design (CAD)
and computer-aided manufacturing (CAM) programs. G-code is a language in
which people tell computerized machine tools how to make something. The
"how" is defined by instructions on where to move, how fast to move, and what
path to move.

22. 22
CNC Program
CNC Program:
G71G94F10
G75Z0
G75X0Y0
M06T01D1
M03S3000
G0G90G54X0Y0
G0Z10
G01Z-0.05
G01X0Y2
G01X2Y2
G01X2Y0
G01X0Y0
G01Z0
G0G90Z50
G75Z0M05
G75X0Y0
M30

23. 23
5. Association of DAQ System to CNC
Data acquisition is the process of sampling signals that measure real world
physical conditions and converting the resulting samples into digital numeric
values that can be manipulated by a computer. In our project, DAQ system has
helped us in converting the voltage fluctuations to force parameters. LabView is
a software which shows the final output in the form of graphs.
DAQ System associated with CNC

24. 24
Experimental Setup
1
• Software Simulation
2
• Selection of Specimen & its
material
3
• Pre Experimental Setup of Sensors,
Wheatstone Bridge & Tool.
4
• CNC Coding
5
• Association of DAQ System
6
• Working on Specimen
7
• Procurement of Graphs

25. 25
Experimental Outcome
The main aim of our project was to obtain an extra parameter such as Force by
the use of DAQ system associated with CNC Machine. By obtaining the Force
parameter we could optimise the cost, resources & time. The following are the
graphs between Force & Time in the direction X & Z.

26. 26

27. 27
Conclusion
1. From this activity, we have learned how to organize the CNC Machine
(Micro Milling) and understand the operation involved.
2. Besides that, we also know the purpose of the main parts of this machine.
3. We have used the Data Acquisition System in CNC Machine for obtaining
the required parameters at a great degree of accuracy & precision.
4. An extra feedback parameter (Force) is obtained which can be used to
optimise the micro milling process. This has helped us in saving the time &
material by making changes in parameters which is affecting it.

28. 28
References
1. M Rahman, A Senthil Kumar, J.R.S Prakash : Micro milling of pure copper.
2. Young-bong Bang , Kyung-min Lee, Seungryul Oh : 5-axis micro milling
machine for machining micro parts.
3. I. Tansel , O. Rodriguez, M. Trujillo, E. Paz, W. Li : Micro-end-milling—I.
Wear and breakage.
4. J. Chae, S.S. Park, T. Freiheit : Investigation of micro-cutting operations.
5. I. Tansel , A. Nedbouyan, M. Trujillo, B. Tansel : Micro-end-milling—II.
Extending tool life with a Smart Workpiece Holder (SWH).
6. I. Tansel , M. Trujillo, A. Nedbouyan, C. Velez, Wei-Yu Bao, T.T. Arkan,
B. Tansel : Micro-end-milling—III. Wear estimation and tool breakage
detection using acoustic emission signals.
7. Goran Mijušković, Peter Krajnik & Janez Kopač : Analysis of tool deflection
in micro milling of graphite electrodes.
8. Elisa Vázquez & Jéssica Gomar & Joaquim Ciurana & Ciro A.
Rodríguez : Evaluation of machine-tool motion accuracy using a CNC
machining center in micro-milling processes.