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    RoboticsRobotics andand AutomationAutomation

    MFET5023

    Dr. Sang-Heon LEE

    School ofAdvanced Manufacturing and Mechanical Engineering

    University of South Australia

    Lecture 2-1

    Introduction to industrial robots

    Lecture outline

    This lecture will cover

    1. Why robots and why not

    2. Definition of robot

    3. Brief history of robot4. Some terms of robot

    5. Configuration of industrial robots

    Introduction

    Automation and Robots are two closely related

    technologies

    Robot is a mechanical device that assists industrial

    automation

    Robots are typically used in processing, transport,

    assembly and other areas of automation

    The sensory capability and interaction of a robot with

    its environment are two key areas to be improved for

    the wider applications of robots.

    Why robot? Reduce labour cost

    Eliminate dangerous jobs

    Increase output rate reduceroduction cost.

    Improve production quality

    Reduce material waste

    Longer useful time

    Do not tire or grumble nohealth claims (except somemaintenance).

    Work 24 hours each day.

    Why not robot? Replace humans in workforce (?)

    low skilled workers

    Initial investment cost is quitehi h for small firms

    Limited technology: sensors andgrippers etc.

    Difficult to adapt to new problemsand environments.

    Impossible to make decisions,and define goals on its own.

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    Why robot & why not? Automatic harvesting system

    examples

    ov e range arves ng

    Movie 2 (Robot harvesting)

    Definition of (industrial) robot

    The robot institution of AmericaAn industrial robot is a reprogrammable deviceto both manipulate and transport parts, tools or

    through variable programmed motions for theperformance of specific manufacturing tasks.

    What is a robot?

    Robots in the real world

    tEODor (bomb disposal)BigDog

    What is a robot?

    Robots in our imagination

    What is a robot?

    However, there is no sharpboundaries no widely accepteddefinition of what a robot is.

    Hubo1.wmv

    Some history of Robots Mechanical Duck (J. De Vaucanson, 1738)

    The Jacquard Loom (J. M. Jacquard, 1801) - Punch cardtechnique

    Punch card techniqueMechanical duck

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    Some history of Robots Maillardet's Automaton (H. Maillardet, 1805) Mechanical Horse (L. Rygg, 1893)

    autom.wmv

    The origin of term Robots Karel Capek, 1921

    The origin of the Word robotfrom the play R.U.R. (RossumsUniversal Robots .

    Robot is from Czech word worker

    Robot is built to save mankindfrom work but used in a war to killpeople Eventually, robot wipeout all humans.

    Made robot become the bad guy.

    The origin of Robots

    Isaac Asimov, 1950

    A novel titled I Robot.

    e or g n o e or ro o cs

    A more positive attitude towards

    technology The definition of robot in this book: an

    active, artificial agent to help people in thephysical world.

    The origin of Industrial Robots 1961 UNI MATE: the first

    industrial robot

    Began work at GM with-

    following step-by-step tasks

    stored on a magnetic drum. With 6 axes to stack hot

    pieces of die-cast metal.

    Unimate.mpg

    industrial robot: in real world

    Applications of robots in industry has beenexpanded a lot.

    Still, an industrial robot is a one-armed, blind idiot

    speak, see or hear.

    Application areas

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    Typical industrial robots: Terms

    Links: rigid bodies that form therobot manipulator.

    Joints: connect neighbouringn s a ow ng e er ro ary

    (revolute) or translating relativemotion (prismatic).

    End effector: the tip of themanipulator. Gripper, weldingtorch, electromagnetic, suctioncups, etc.

    Robot joint types Prismatic (L) Revolute (R)

    by Joint angles by joint offset

    The relative displacement between joints described

    Typical industrial robots

    Arm Movement9 Joint 1: Waist Arm

    sweep.9 Joint 2: Shoulder

    Shoulder swivel.

    9 Joint 3: Elbow- Elbowextension.

    Wrist Movement9 Joint4,5,6-Roll, Pitch and

    yaw

    Degree of Freedom DOF (Degree of Freedom)-

    Several definitions

    1. DOF=number of joints.

    2. Spatial representation 6DOF to 3-D coordinate

    system. The number of DOF available influences the robots ability

    to orientate the end-effector in 6 dimensional space.

    Pose to describe position and orientation of robot arm.

    6 independent joints required to have 6 DOF.

    Work Space Work space: the space

    reachable by a manipulator.

    Work space is the region

    position its end-effector.

    Robot configuration types,and the length of links willmainly decide the size ofwork space.

    Work Space

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    Work space: restriction Work Volume: Collision

    Work space: Safety Type of robot: Configurationof industrial robots

    Cartesian.

    Cylindrical.

    o ar p er ca .

    SCARA (Selective Compliance AssemblyRobot Arm).

    Articulated (Jointed arm configuration).

    Multiple joint (Spine) configuration

    Parallel configuration

    Cartesian configuration (LLL)

    Only with 3 prismatic joints-Move along x,y,z

    direction in straight lines (LLL).

    Motion of each axis is limited to one direction.

    If the robot is mounted from above in a bridgeframe gantry robot.

    Cartesian configuration (LLL)

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    Cylindrical configuration (RLL)

    Rotate about its base and move linearly inhorizontal and vertical planes (r, z, )-1R2L

    Robust, and high work area to floor area ratio.

    Limited movements.

    Cylindrical configuration (RLL)

    Spherical (polar) configuration(RRL)

    Rotate about its base as well as its head, andmove in and out (r, , )-2R1L.

    - ,first industrial robot.

    Handling of heavy load.Ex, in a long straightreach into a press ormoulding machine.

    Spherical (polar) configuration(RRL)

    SCARA configuration (RRL)

    Most common configuration of assembly robot.(2R1L)

    Very useful in assembly operations whereinsertions o o jects into o es are require .

    Scara.avi

    Vertical prismaticmovement can apply aforce to insert parts withhigh degree of rigidity.

    SCARA configuration (RRL)

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    Articulated configuration (RRR)

    Only with revolute joints.

    Most-widely used configuration.

    of arms.

    Compact: larger workspace per floor spaceoccupied.

    Articulatedconfiguration

    Articulated configuration

    MovieF3MachLoading.mpeg

    MovieF3CVbootdeflashing.mpeg

    Robot Configuration- Summary

    (a) Cartesian

    (b) Polar(Spherical)

    c y n r ca

    (d) SCARA

    (e) Articulated(Jointed armconfiguration)

    Multiple joint (spine)configuration No prismatic or revolute joints a

    series of plates will be adjustedwhen necessary.

    Flexibility and articulationcapability

    Rigidity and repeatability is stillunder the question.

    Parallel configuration

    Consists of a fixed "base"platform, connected to anend-effector platform by

    " ".

    high structural stiffness

    Can handle heavy load

    But very complicated control

    ABBIrb340.mvw

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    How to choose a configuration ?

    No strict rule exists which configuration youshould choose for a given task case by case.

    Sometimes it is more efficient to use a specifictask oriented equipment rather than a moregeneral robot.

    Also it is an important issue to consider aDESIGN FOR AUTOMATION ASSEMBLY beforeyou just install a robot operation to replace thecurrent manual operation.