Robotics Unit2
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Transcript of Robotics Unit2
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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.