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					             Dr. HABEEB HATTAB HABEEB

                Office: BN-Block, Level-3,
                         Room-088
             Email: hbuni61@yahoo.com
             Ext. No.: 7292

University TENAGA Nasional   Lecturer: Dr. HABEEB ALANI
                         University TENAGA National




                        College Of Engineering
                        Mechanical Department

Lecture Note

 University TENAGA Nasional     Lecturer: Dr. HABEEB ALANI
                   Computer Aided Manufacturing




                             CAM
    University TENAGA
University TENAGA Nasional                 HABEEB ALANI
                             Lecturer: Dr. Lecturer: Habeeb Al-Ani
    Nasional
                    Overview

•   Computer Aided Manufacturing Defined
•   Brainstorming Exercise
•   CAM activities
•   How It Works
•   Summary
•   Conclusion

University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
  Computer Aided Manufacturing

• What is Computer Aided Manufacturing?
    – It is “control of the manufacturing process by
         computers” involving the integration of CAD
         engineering data and the computerized
         equipment which manufactures the product.




University TENAGA
                        Lecturer: Dr. HABEEB ALANI
Nasional
   Computer Aided Manufacturing
• Other definitions:
    – “Computer aided manufacturing concerns the use
      of algorithms for planning and controlling
      fabrication processes.”

    – Computer aided manufacturing is “the use of
      computers for managing manufacturing
      processes.”



 University TENAGA
                     Lecturer: Dr. HABEEB ALANI
 Nasional
    Computer Aided Manufacturing

•   Using technology to produce
•   Leveraging capital investments
•   Increasing productivity through automation
•   Decreasing lead time through programming
    and controlled machinery



University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
                    Brainstorming Exercise

• How can CAM benefit your company?
    – Integrate design and manufacturing
    – Make mass customization possible
    – Reduce costs
    – Leverage computing power
    – Automate manufacturing processes


University TENAGA
                           Lecturer: Dr. HABEEB ALANI
Nasional
                    Brainstorming Exercise

• Identify benefits and costs of CAM:
    – Direct Benefits
    – Indirect Benefits
    – Tangible Costs
    – Intangible Costs




University TENAGA
                           Lecturer: Dr. HABEEB ALANI
Nasional
                    Brainstorming Exercise


• What processes in your company could be
  more efficient through CAM?




University TENAGA
                           Lecturer: Dr. HABEEB ALANI
Nasional
                    CAM activities

• Essentially the collection of computer
  technologies used in manufacturing
    – Computer Numerical Control (CNC)
    – Direct Numerical Control (DNC)
    – Flexible Manufacturing System (FMS)
    – Robots
    – Automated material Handling Systems

University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                    CAM activities

• Computer Numerically Controlled (CNC)
    – Machine that is controlled by computer
    – Utilizes monitor and keyboard for operator
      interaction
    – Facilitates greater control over quality
    – Allows machine to monitor the maintenance of
      its parts


University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                    CAM activities

• Direct Numerical Control (DNC)
    – Each machine contains own microprocessor
    – Entire bank of machines controlled by a single
      central computer
    – If used with automated material handling,
      considered to be a flexible manufacturing system



University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
              CAM activities

• Direct Numerical Control (DNC)
              CAM activities

• Direct Numerical Control (DNC)
                    CAM activities


• Flexible Manufacturing System (FMS)
    – Numerous computer-controlled machines fed by
      automated material handling system
    – Allows for broad and deep product mix
    – Minimal setup times enable small lot sizes




University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                    CAM activities


• Robots
    – Mechanical manipulators that can be accessed
      with programming method
    – Consistent, repetitive-motion tolerant
    – Ideal for tasks that are hazardous to humans




University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                      CAM activities

• Automated Materials Handling System
    – System where raw materials are automatically
      fed into machines
    – Examples:
           • Conveyor belts
           • Automated Guided Vehicles (AGV)
           • Automated Storage and Retrieval Systems (ASRS)



University TENAGA
                           Lecturer: Dr. HABEEB ALANI
Nasional
                    How It Works

1. Product is conceived by engineer
2. Product is designed using CAD software
3. CAD data is transferred to manufacturing
   machine’s memory
4. Machine uses the CAD data to produce the
   product, with little human intervention


University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                      How It Works
• Old System (without CAM)
    – Product is designed with CAD software
          • Each production machine is programmed individually

          OR – if not automated :
          • Employees are trained on proper production of the
            product




 University TENAGA
                           Lecturer: Dr. HABEEB ALANI
 Nasional
                      How It Works

• New System (using CAM)
    – Product is designed with CAD software
           • Product specifications are sent over the plant
             network to each machine
           • Machines have ‘intelligence’ to produce the products
             without human intervention




University TENAGA
                            Lecturer: Dr. HABEEB ALANI
Nasional
    – CAM solution:
           • Enables faster turnaround of new products
           • Reduces waste by using raw materials more
             efficiently
           • Generates costs based on design specifications




University TENAGA
                            Lecturer: Dr. HABEEB ALANI
Nasional
                       Summary

• Here’s what we’ve looked at so far….
    – Definition
    – Brainstormed
    – CAM activities
    – How It Works
    – CAM solution


University TENAGA
                       Lecturer: Dr. HABEEB ALANI
Nasional
                    Conclusion

• CAM enables companies to leverage capital
  investment
• CAM allows for cost savings that can be
  passed on to the final consumer
• CAM utilizes human resources more
  efficiently to minimize labor costs


University TENAGA
                     Lecturer: Dr. HABEEB ALANI
Nasional
                    Remember & remember X 1000




If   you want to be part of a profession dedicated to quality

and continuous improvement, consider CAM as your career
of choice…




     University TENAGA
                             Lecturer: Dr. HABEEB ALANI
     Nasional
University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
            CAM Systems & CNC
                Machine


University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
                     History
• 1955 - John Parsons and US Air Force define a
  need to develop a machine tool capable of
  machining complex and close tolerance
  aircraft parts with the same quality time after
  time. MIT is the subcontractor and builds the
  machine for the project.




 University TENAGA
                     Lecturer: Dr. HABEEB ALANI
 Nasional
                     History: Continued
• 1959 - MIT announces Automatic
  Programmed Tools (APT) programming
  language
• 1960 - Direct Numerical Control (DNC). This
  eliminates paper tape punch programs and
  allows programmers to send files directly to
  machine tools


 University TENAGA
                          Lecturer: Dr. HABEEB ALANI
 Nasional
                    History: Continued
   • 1968 - Kearney & Trecker machine tool
     builders market first machining center
   • 1970’s - CNC machine tools & Distributed
     Numerical Control
   • 1980’s - Graphics based CAM systems
     introduced. Unix and PC based systems
     available


University TENAGA
                         Lecturer: Dr. HABEEB ALANI
Nasional
                    History: Continued

• 1990’s - Price drop in CNC technology
• 1997 - PC- Windows/NT based “Open
  Modular Architecture Control (OMAC)”
  systems introduced to replace “firmware”
  controllers.



University TENAGA
                         Lecturer: Dr. HABEEB ALANI
Nasional
              Control Systems
• Open-Loop Control
  – Stepper motor system
  – Current pulses sent from control unit to motor
  – Each pulse results in a finite amount of revolution
    of the motor001” is possible
                     Control Systems
• Open-Loop Limitations
    – Control unit “assumes” desired position is
      achieved
    – No positioning compensation
    – Typically, a lower torque motor
• Open-Loop Advantages
    – Less complex, Less costly, and lower maintenance
      costs

 University TENAGA
                        Lecturer: Dr. HABEEB ALANI
 Nasional
                 Control Systems
• Closed-Loop Control
  – Variable DC motors - Servos
  – Positioning sensors -Resolvers
     • Feedback to control unit
     • Position information compared to target location
     • Location errors corrected
                        Control Systems

                    • Closed-Loop Advantages
                      – DC motors have the ability to reverse
                        instantly to adjust for position error
                      – Error compensation allows for greater
                        positional accuracy (.0001”)
                      – DC motors have higher torque ranges..
                        stepper motors



University TENAGA
                              Lecturer: Dr. HABEEB ALANI
Nasional
                        Control Systems

                    • Closed-loop limitations
                      – Cost




University TENAGA
                               Lecturer: Dr. HABEEB ALANI
Nasional
     Three Basic Categories of Motion
                 Systems

• Point to Point - No contouring capability
• Straight cut control - one axis motion at a
  time is controlled for machining
• Contouring - multiple axis’s controlled
  simultaneously



University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
     Three Basic Categories of Motion
                 Systems




University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
              CNC - NC Machine Tools

• Computer Numerical Control (CNC) - A numerical
   control system in which the data handling, control
   sequences, and response to input is determined by
   an on-board computer system at the machine tool.




University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                                      CNC

• Advantages
      – Increased Program storage capability at the machine tool
      – Program editing at the machine tool
      – Control systems upgrades possible
      – Option -resident CAM system at machine tool
      – Tool path verification




University TENAGA
                                 Lecturer: Dr. HABEEB ALANI
Nasional
                    Machining Centers

 – Machine motion is programmable

 – Servo motors drive feed mechanisms for tool
     axis’s

 – Positioning feedback is provided by resolvers to
     the control system



University TENAGA
                         Lecturer: Dr. HABEEB ALANI
Nasional
                            NC

   • Numerical Control (NC) - A control system
     which primarily processes numeric input.
     Limited programming capability at the
     machine tool. Limited logic beyond direct
     input. These types of systems are referred
     to as “hardwire controls” and were
     popular from the 1950’s to 1970’s.


University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional
                    Machining Centers

      • A machining center can be defined as
        a machine tool capable of:
             – Multiple operation and processes in a
               single set-up utilizing multiple axis
             – Typically has an automatic mechanism to
               change tools



University TENAGA
                          Lecturer: Dr. HABEEB ALANI
Nasional
                    Machining Centers

• Example - A turning center capable of OD
  turning, external treading, cross-hole drilling,
  engraving, and milling. All in machining is
  accomplished in one “set-up.” Machine may
  have multiple spindles.



University TENAGA
                         Lecturer: Dr. HABEEB ALANI
Nasional
         Programming Methods-APT

    – Developed as a joint effort between the
      aerospace industry, MIT, and the US Airforce

    – Still used today and accounts for about 5 -10% of
      all programming in the defense and aerospace
      industries



University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                    Machining Centers




University TENAGA
                         Lecturer: Dr. HABEEB ALANI
Nasional
                    Programming Methods

• Automatically Programmed Tools (APT)
    – A text based system in which a programmer
      defines a series of lines, arcs, and points which
      define the overall part geometry locations.
      These features are then used to generate a
      cutter location (CL) file.




University TENAGA
                          Lecturer: Dr. HABEEB ALANI
Nasional
         Programming Methods-APT


   – Requires excellent 3D visualization skills

   – Capable of generating machine code for
     complicated part programs
         • 5 axis machine tools




University TENAGA
                              Lecturer: Dr. HABEEB ALANI
Nasional
         Programming Methods-APT

• Part definition
                    – P1=Point/12,20,0
                    – C1=Circle/Center,P1,Radius,3
                    – LN1=Line/C1. ATANGL,90



• Cutter Commands
                    – TLRT,GORT/LN1.TANTO,C1
                    – GOFWD/C1,TANTO,L5




University TENAGA
                                     Lecturer: Dr. HABEEB ALANI
Nasional
       Programming Methods-CAM

• Computer Aided Machining (CAM) Systems
     – Graphic representation of the part
     – PC based
     – Integrated CAD/CAM functionality
     – “Some” built-in expertise
                    – Speed & feed data based on material and tool specifications




University TENAGA
                                     Lecturer: Dr. HABEEB ALANI
Nasional
       Programming Methods-CAM


    – Tool & material libraries
    – Tool path simulation
    – Tool path editing
    – Tool path optimization
    – Cut time calculations for cost estimating



University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
       Programming Methods-CAM


   – Import / export capabilities to other systems
         • Examples:
                – Drawing Exchange Format (DXF)
                – Initial Graphics Exchange Standard (IGES)




University TENAGA
                                  Lecturer: Dr. HABEEB ALANI
Nasional
        The Process CAD to NC File

     • Start with graphic representation of
       part
            – Direct input
            – Import from external system
                    • Example DXF / IGES
            – 2D or 3D scan
                    • Model
            (At this point you have a graphics file of your
              geometry)

University TENAGA
                                   Lecturer: Dr. HABEEB ALANI
Nasional
          The Process CAD to NC File

                    • Define cutter path by selecting
                      geometry
                       –   Contours
                       –   Pockets
                       –   Hole patterns
                       –   Surfaces
                       –   Volume to be removed
                    (At this point the system knows what you want to cut)



University TENAGA
                                  Lecturer: Dr. HABEEB ALANI
Nasional
      The Process CAD to NC File

• Define cut parameters
     – Tool information
            • Type, Rpm, Feed
     – Cut method
            • Example - Pocket mill zig-zag, spiral, inside-out
            • Rough and finish parameters
(At this point the system knows how you want to cut the
   part)



University TENAGA
                                 Lecturer: Dr. HABEEB ALANI
Nasional
         The Process CAD to NC File


• Execute cutter simulation
     – Visual representation of cutter motion
• Modify / delete cutter sequences

(At this point the system has a “generic” cutter location (CL) file
   of the cut paths)




 University TENAGA
                          Lecturer: Dr. HABEEB ALANI
 Nasional
           The Process CAD to NC File
• Post Processing
    – CL file to machine specific NC code
• Filters CL information and formats it into NC
  code based on machine specific parameters
    – Work envelope
    – Limits - feed rates, tool changer, rpm’s, etc.
    – G & M function capabilities


 University TENAGA
                       Lecturer: Dr. HABEEB ALANI
 Nasional
                    Output: NC Code


• Numerical Control (NC) Language
    – A series of commands which “direct” the cutter
      motion and support systems of the machine
      tool.




University TENAGA
                        Lecturer: Dr. HABEEB ALANI
Nasional
                     Output: NC Code
• G-Codes (G00, G1, G02, G81)

• Coordinate data (X,Y,Z)

• Feed Function (F)

• Miscellaneous functions (M13)

• N - Program sequence number

• T - Tool call

• S - Spindle command

 University TENAGA
                            Lecturer: Dr. HABEEB ALANI
 Nasional
              Output: NC Code

• NC Program Example
     –   N01G90 G80
     –   N03 GOO T12 M06
     –   N05 GOO X0 Y0 Z.1 F10 S2500 M13
     –   N07 G1Z-.5
     –   N09 G02 X-10. I0J0F20
     –   N13 X0Y10
     –   N17 X10Y0
     –   N19 X0Y-10
     –   N21 X-10Y0
     –   N23 M2

University TENAGA
                             Lecturer: Dr. HABEEB ALANI
Nasional
              Example of CNC Programming



      • What What Must Be Done To Drill A
        Hole On A CNC Vertical Milling
        Machine




University TENAGA
                      Lecturer: Dr. HABEEB ALANI
Nasional
                                                      Tool Home


 Top
 View



                      1.) X & Y Rapid To Hole Position
Front
View

  University TENAGA
                         Lecturer: Dr. HABEEB ALANI
  Nasional
 Top                2.) Z Axis Rapid Move
 View                   Just Above Hole



                    3.) Turn On Coolant

                     4.) Turn On Spindle

Front                          .100”
View

University TENAGA
                       Lecturer: Dr. HABEEB ALANI
Nasional
 Top
 View
                    5.) Z Axis Feed Move to
                    Drill Hole

Front
View

University TENAGA
                        Lecturer: Dr. HABEEB ALANI
Nasional
 Top
 View               6.) Rapid Z Axis Move
                    Out Of Hole



Front
View

University TENAGA
                       Lecturer: Dr. HABEEB ALANI
Nasional
 Top
 View               7.) Turn Off Spindle

                       8.) Turn Off Coolant

                    9.) X&Y Axis Rapid
                    Move Home
Front
View

University TENAGA
                       Lecturer: Dr. HABEEB ALANI
Nasional
  Here’s The CNC Program!           Tool At Home



 Top                O0001
 View                N005 G54 G90 S600 M03
                     N010 G00 X1.0 Y1.0
                     N015 G43 H01 Z.1 M08
                    N020 G01 Z-.75 F3.5
                    N025 G00 Z.1 M09
Front               N030 G91 G28 X0 Y0 Z0
View                N035 M30

University TENAGA
                            Lecturer: Dr. HABEEB ALANI
Nasional
                                       Tool At Home



 Top                O0001
 View               O0001
                            Number Assigned to this program




Front
View

University TENAGA
                               Lecturer: Dr. HABEEB ALANI
Nasional
                                     Tool At Home



 Top                O0001
 View                N005 G54 G90 S600 M03
                    N005   Sequence Number
                    G54    Fixture Offset
                    G90    Absolute Programming Mode
                    S600   Spindle Speed set to 600 RPM

                    M03    Spindle on in a Clockwise Direction


Front
View

University TENAGA
                             Lecturer: Dr. HABEEB ALANI
Nasional
 Top                O0001
 View                N005 G54 G90 S600 M03
                     N010 G00 X1.0 Y1.0
                    G00    Rapid Motion
                    X1.0   X Coordinate 1.0 in. from Zero
                    Y1.0   Y Coordinate 1.0 in. from Zero


Front
View

University TENAGA
                             Lecturer: Dr. HABEEB ALANI
Nasional
 Top                O0001
 View                N005 G54 G90 S600 M03
                     N010 G00 X1.0 Y1.0
                     N015 G43 H01 Z.1 M08
                    G43   Tool Length Compensation
                    H01   Specifies Tool length compensation
                    Z.1   Z Coordinate .1 in. from Zero
Front               M08   Flood Coolant On

View

University TENAGA
                            Lecturer: Dr. HABEEB ALANI
Nasional
 Top                O0001
 View                N005 G54 G90 S600 M03
                     N010 G00 X1.0 Y1.0
                     N015 G43 H01 Z.1 M08
                    N020 G01 Z-.75 F3.5
                    G01     Straight Line Cutting Motion
                    Z-.75   Z Coordinate -.75 in. from Zero
Front               F3.5    Feed Rate set to 3.5 in./min.
View

University TENAGA
                              Lecturer: Dr. HABEEB ALANI
Nasional
 Top                O0001
 View                N005 G54 G90 S600 M03
                     N010 G00 X1.0 Y1.0
                     N015 G43 H01 Z.1 M08
                    N020 G01 Z-.75 F3.5
                    N025 G00 Z.1 M09
Front               G00   Rapid Motion
                    Z.1   Z Coordinate .1 in. from Zero
View                M09   Coolant Off


University TENAGA
                            Lecturer: Dr. HABEEB ALANI
Nasional
                    O0001
                     N005 G54 G90 S600 M03
 Top
 View                N010 G00 X1.0 Y1.0
                     N015 G43 H01 Z.1 M08
                    N020 G01 Z-.75 F3.5
                    N025 G00 Z.1 M09
                    N030 G91 G28 X0 Y0 Z0
                    G91      Incremental Programming Mode
Front               G28      Zero Return Command

View                X0, Y0, Z0
                             X,Y,& Z Coordinates at Zero


University TENAGA
                             Lecturer: Dr. HABEEB ALANI
Nasional
   Top              O0001
   View              N005 G54 G90 S600 M03
                     N010 G00 X1.0 Y1.0
                     N015 G43 H01 Z.1 M08
                    N020 G01 Z-.75 F3.5
                    N025 G00 Z.1 M09
Front               N030 G91 G28 X0 Y0 Z0
View                N035 M30
                         M30         End of Program




University TENAGA
                         Lecturer: Dr. HABEEB ALANI
Nasional
                    Output: NC Code - Canned Cycles




University TENAGA
                                      Lecturer: Dr. HABEEB ALANI
Nasional
                        CAD to NC Code
               Import       DXF        Geometry
                File        IGES         Direct input



                                       Tool Path Generation
                                        What you want to cut
                                        How you want to cut
                                         Tool Type
                                CL       Rpm’s – Feeds
             Post Process                Method
                                File
                                           Canned cycles
                                           Cut direction



           NC Code            OEM
        N1 G80 G90           Custom
        N3 G0 T01 M06       Language
        N5 G0 X0 Y0

University TENAGA
                                              Lecturer: Dr. HABEEB ALANI
Nasional
     Advantages of CNC Machine Tools


      •    Ease of part duplication
      •    Flexibility
      •    Repeatability
      •    Quality control through process control




University TENAGA
                                   Lecturer: Dr. HABEEB ALANI
Nasional
     Advantages of CNC Machine Tools

     • Accommodates simple to complex parts
       geometry
     • Improved part aesthetics
     • Increased productivity
     • Technology costs are decreasing



University TENAGA
                             Lecturer: Dr. HABEEB ALANI
Nasional
     Advantages of CNC Machine Tools

     •    Reduced set-up time
     •    Reduced lead times
     •    Reduced inventory
     •    Better machine utilization
     •    Job advancement opportunities


University TENAGA
                                 Lecturer: Dr. HABEEB ALANI
Nasional
     Advantages of CNC Machine Tools

    • CNC machine tools are more rigid than
      conventional machine tools
           – $$$- Climb milling requires about 10 - 15 % less horsepower vs.
             conventional cutting, but requires a ridged machine tool with
             no backlash
           – Increased Rpm’s and feeds




University TENAGA
                                                 Lecturer: Dr. HABEEB ALANI
Nasional
University TENAGA
                    Lecturer: Dr. HABEEB ALANI
Nasional

				
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