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Robotics (and automation)

MIT 2.008 / 2.008x – Prof. John Hart

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What is automation?

What is an industrial robot?

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Automation:

automatically controlled operation of an apparatus,

process or system by mechanical or electronic

devices that take the place of human labor*

*Wilson, Implementation of Robot Systems

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Automation in manufacturing systems

Machines

Material flow and handling

Robotic manipulation

Local controllers (machines / workcells)

Factory network controllers (supervision, optimization)

Requirements for implementation

Coordination of process rates

Robustness against faults

Online monotoring / control

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Automation: filling water bottles

https://www.youtube.com/watch?v=EjkOiBXI14o

Bottle molding: 2,250/hr https://www.youtube.com/watch?v=soiGsZj7hn0&list=PL167A9254F5245075&index=33

All videos from Krones: https://www.youtube.com/playlist?list=PL167A9254F5245075

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Automation:

automatically controlled operation of an apparatus,

process or system by mechanical or electronic

devices that take the place of human labor

Industrial robot:

an automatically controlled, re-programmable,

multipurpose manipulator programmable in three or

more axes, which may be either fixed in place or

mobile for use in industrial automation applications

(according to the international federation of robotics)

from Wilson, Implementation of Robot Systems

2.008-F16 | 7from Wilson, Implementation of Robot Systems

The first industrial robot, the ‘Unimate’

Invented/built by Joseph Engelberger and

George Devol (company formed 1956)

Hydraulically driven arm with instructions

read from magnetic drum

Initial use to stack die cast parts at General

Motors plant in New Jersey

First major industrial robot installation (1969)

Went from 40% to 90% automated spot welding

3000 robots in use by 1973 (mfg partnership

between Unimation and Kawasaki of Japan)

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Today’s agenda

Why automation and robotics in manufacturing?

Common robotic manipulators used in manufacturing:

articulated, selective compliance (SCARA), delta

Geometry and workspace

Applications

Comparing performance and capability tradeoffs

Grippers (‘end effectors’)

Emerging trends and technologies

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Why use robotics and automation in

manufacturing?

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Why use robotics and automation in mfg?

from Wilson, Implementation of Robot Systems

(Potentially)

Improve product quality and consistency

Improve worker safety/satisfaction (by doing heavy or

dangerous jobs)

Increase production rate

Increase production flexibility

Reduce manufacturing cost

Reduce waste

Save space in high value areas

Some of the above are coupled; rarely are all true

Robots generally not good for operations requiring both

high force and high accuracy (e.g., machining); also takes

time to program and establish accurate path (calibration)

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How can we measure whether a process (or industry in

general) is appropriate for use of robotics?

?

?

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BCG ‘The Robotics Revolution’ https://www.bcgperspectives.com/content/articles/lean-manufacturing-innovation-robotics-revolution-next-great-leap-

manufacturing/

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Artaic: robotic assembly of custom mosaic tile

ARTAIC: https://artaic.com/

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Now >2 million industrial robots in use worldwide

from Wilson, Implementation of Robot Systems

Total number of robots in use: Asia:Europe:Americas = 3:1.5:1

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Predicted growth (source: Boston Consulting Group)

BCG ‘The Rise of Robotics’

https://www.bcgperspectives.com/content/articles/business_unit_strategy_innovation_rise_of_robotics/

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Robotic manipulators

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Articulated robot

Sciavicco, L.; Siciliano, B. Modelling and Control of Robot Manipulators; Advanced Textbooks in Control and Signal Processing;

Springer London: London, 2000; Burckhardt C. Industrial Robots : Proceedings = Robots Industriels : Comptes Rendus = Industrie-

Roboter : Tagungsberichte [e-book]. Basel : Birkhäuser Verlag, 1975

Spherical wrist for end-effector

Waist joint

Shoulder joint

Elbow joint

Wrist

The articulated arm provides the most dexterity within the

working volume.

Errors are cumulative due to the series architecture.

Typical robot sizes range from a reach of 0.5 to over 3.5 m

and carrying capacities from 3 to over 1000 kg.

The end-effector orientation can be independent of position

using a spherical wrist.

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Workspace of articulated manipulator

Sciavicco, L.; Siciliano, B. Modelling and Control of Robot Manipulators; Advanced Textbooks in

Control and Signal Processing; Springer London: London, 2000.

Working envelope End-

effector

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Kuka articulated robot arm

Heavy-duty robot

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Verifying the workspace [: don’t try this with

your robot]

https://www.youtube.com/watch?v=bxbjZiKAZP4 (see description)

There’s a real ride: https://www.youtube.com/watch?v=bSdA_oq1EgU

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Axes 1, 2, and 3

Motors

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Planetary gear

in Axis 6

Power transmission

belts for axes 4, 5, & 6

Motors and Transmissions of Axes 4, 5, and 6

MotorsTransmission

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Brushless AC Servomotor

• Rotor has a rotating permanent magnet and a fixed

armature

• Electronic controller replaces the brush/commutator

assembly of the brushed motor

• High torque to weight ratio, high efficiency and

reliability (compared to brushed motors)

• With windings in the housing, cooling is done by

conduction

AC Servomotor

(Kollmorgen AKM series used in KUKA robots)

Torque is kept (nearly)

constant with speed and

load changes

Reference

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Wave Generator

Flex Spline

Circular Spline

Strain Wave Gear Components

• Motor is connected to the Wave generator

• When the wave generator rotates CW by 3600, Flex Spline

rotates CCW by 2 teeth w.r.t. the Circular Spline (fixed)

• High gear reduction ratios in a small volume (30:1 to 320:1 is

possible Vs 10:1 from planetary gears)

• High positioning accuracy and repeatability (+/- 3 arc

seconds) [1 arc second = 1/3600th of a degree]

• High torque capacity and torsional stiffness

• Low tooth friction losses and wear longer life and high

reliability

Strain wave gear

Operating Principle

Video : Strain Wave Gear Principle

Reference

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How is the robot structure made?

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Maintaining an accurate 3D path

True (exact) value

Repeatability

AccuracyP

robabili

tydensity

Consider discrete vs.

continuous toolpaths (what are

some applications of each?)

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Serial kinematics by HTM (Homogeneous Transformation Matrices)

úúúú

û

ù

êêêê

ë

é -

1000

0100

100001

200010

Y z

y

x

Z

X

200

100

nHn+1

=Rn

n+1pn+1

n

01 3

1

é

ë

êê

ù

û

úú

T = 1H0

2H1....G

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What influences accuracy and repeatability of end

effector position? Structural design (stiffness)

Actuator performance: accuracy, repeatability, stiffness

Manufacturing and assembly tolerances

Calibration

Use case: loads, toolpath dynamics

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Small robot Heavy-duty robot

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Robot calibration using a laser tracker

https://www.youtube.com/watch?v=SLnFq431mJg

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Robot calibration using a laser

tracker

Corner cube

retroreflector: paths of

entry and exit always

parallel

Video: https://www.youtube.com/watch?v=SLnFq431mJg

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Articulated robots for spot welding

FANUC display at IMTS 2014

2.008-F16 | 36FANUC display at IMTS 2014

‘Learning’ vibration control (LVC) robot: uses sensor to adapt trajectory

for speed and accuracy

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A coordinated 3D path

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Lightweighting using 3D printing

http://spectrum.ieee.org/automaton/robotics/humanoids/boston-

dynamics-marc-raibert-on-nextgen-atlas

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SCARA (Selective Compliance Assembly Robot Arm)

Sciavicco, L.; Siciliano, B. Modelling and Control of Robot Manipulators; Advanced Textbooks in Control and Signal Processing; Springer

London: London, 2000; Burckhardt C. Industrial Robots : Proceedings = Robots Industriels : Comptes Rendus = Industrie-Roboter :

Tagungsberichte [e-book]. Basel : Birkhäuser Verlag, 1975

Four-axis arm: positioning in x,y,z and rotation about z

Very rigid in the vertical direction and with compliance in the horizontal plane;

useful for high accuracy positioning in x-y plane (e.g., part insertion)

Planar rotary motion 1

Planar rotary motion 2

Vertical motion

Working envelope

Base rotation

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SCARA for precision assembly and fastening

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Delta (parallel kinematics) robot

http://www.ohio.edu/people/williar4/html/pdf/DeltaKin.pdf; http://www.adept.com/products/robots/parallel/quattro-s650h/intro

Working envelope (example

The parallel or delta configuration

differs from the articulated arm

because the constraints (or

degrees of mobility) are in parallel.

3 degrees of freedom; typically

low payload capacity.

Errors are non-cumulative unlike

the case of series constraint in the

kinematic arm. Also provides high

stiffness (relative to weight) and

high speed.

Mainly used in pick and place

operations, especially in the food

industry and also in some

assembly applications.

Rotations

controlled by

actuators

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Delta robot

Pancakes: https://www.youtube.com/watch?v=v9oeOYMRvuQ

Salami snacks: https://www.youtube.com/watch?v=aPTd8XDZOEk

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How do the speed and

repeatability compare to an

articulated robot?

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0

20

40

60

80

100

120

140

0 2 4 6 8 10 12

Re

pe

atab

ility

(µ

m)

Speed (m/s)

Speed vs Repeatability by Arm Type

6 DOF avg

SCARA avg

Delta avg

Speed vs repeatability

Articulated

SCARA

Delta picker

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Stiffness: serial versus parallel

Slocum

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Cartesian robots: Gantry (serial or parallel)

http://blenderartists.org/forum/attachment.php?attachmentid

=371530&d=1428277647&thumb=1

Shipbuilding crane

http://www.rockymountainwaterjet.com/small_jet.jpg

OMAX waterjet Stacking system

http://seamco.be/machine/

cartesian-robot-rc-600/137

Translation along

three axes

FDM printers

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Single-point metal forming (Ford) Pair of stiff parallel robots iteratively

deform sheet metal parts (= prototyping

method)

Operation

CAM software

Video: https://www.youtube.com/watch?v=iNQ40MYwZqw

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Standard grippers for material handling

http://www.ardelis.co.za/products-grippers/

http://www.motoman.com/products/peripherals/

adaptive-gripper.php

http://us.schmalz.com/aktuelles/produkte/vaku

umgreifsysteme/00932/

Conventional clamp Three-finger gripperVacuum suction pads

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Material handling: Nachi 2-armed robot

exhibit at IMTS 2014

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Tooling cost

+

Equipment cost

+

Material cost

+

Overhead cost

How would we determine cost of adding robots?

n

CC oh

4

[$/part]

C3=mC

m

1- f( )

CT

=C1+C

2+C

3+C

4

t

t

n

N

N

CC Roundup1

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BCG ‘The Robotics Revolution’ https://www.bcgperspectives.com/content/articles/lean-manufacturing-innovation-robotics-revolution-next-great-leap-

manufacturing/

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The future?

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Picking and stocking warehouse shelves (see ‘Amazon Picking Challenge’)

http://spectrum.ieee.org/automaton/robotics/industrial-

robots/team-delft-wins-amazon-picking-challenge

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http://spectrum.ieee.org/automaton/robotics/artificial-intelligence/google-wants-robots-to-acquire-

new-skills-by-learning-from-each-other

https://research.googleblog.com/2016/03/deep-learning-for-robots-learning-from.html

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Flexible automation: Rethink Robotics “Baxter”

Programmable manually (‘teach’ by holding the robot’s end effector and

moving it through the path)

Tolerant to variabilities e.g. in part position on conveyor

Force feedback enabling the robot to adapt to variations without damage but LOW

STIFFNESS

Working radius = 1210 mm; maximum payload (including end-effector) = 2.2 kg

7 degrees of freedom per arm Degrees of mobility = 7 per arm

Embedded vision system

http://www.rethinkrobotics.com

https://www.youtube.com/watch?v=DKg-GvPyNLc

https://www.youtube.com/watch?v=KpqaBKyZGeE&feature=youtu.be

2.008-F16 | 56exhibit at IMTS 2014

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References

1 Introduction

Tesla factory: Photo #54521 Copyright NOTCOT INC 2006-2016

iRobot Roomba cleaning robot image © Molaunhuevo.com

Clearpath robot with boxes: photo © Clearpath Robotics, 2015

Big saw robot: Photo © 2016 MIT. All rights reserved.

MIT campus Sean Collier memorial: Photo © John Hart. Used with permission.

Brick assembly robot: Photo from MIT Technology Review © MIT.

Automated Dynamics fiber placement machine: Image from Automated Dynamics ©

Agarik SAS.

Humanoid robot: Screenshot image © Copyright 2016 IEEE Spectrum

2 Automated Water Bottling

Krones water production video + product pictures © Krones AG 2016

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References

3 Why Automate

Early robot: Photo © 2016 Maplegate Media

Early car production plant: Photo © 2016 Maplegate Media

Robotics impact on industries graphic: Image Copyright © 2016 The Boston Consulting

Group. All rights reserved

Artaic mosaic robot © Copyright 2016 - Artaic LLC. Artaic® is a registered service mark

of Artaic LLC.

Automation potential graphic © 1996-2016 McKinsey & Company

Worldwide spending on robotics: Image Copyright © 2016 The Boston Consulting Group.

All rights reserved

Tesla Advanced Automation blog post © Tesla Motors, 2016

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References

4 Articulated Robots

Articulated Robot: Sciavicco, L.; Siciliano, B. Modelling and Control of Robot

Manipulators; Advanced Textbooks in Control and Signal Processing; Springer London:

London, 2000

Articulated Robot: Burckhardt C. Industrial Robots : Proceedings = Robots Industriels :

Comptes Rendus = Industrie-Roboter : Tagungsberichte [e-book]. Basel : Birkhauser

Verlag, 1975 2.008-F16 | 20

Kuka robot: Photo © Kuka AG 2013

Robotic workspace: Sciavicco, L.; Siciliano, B. Modelling and Control of Robot

Manipulators; Advanced Textbooks in Control and Signal Processing; Springer London:

London, 2000

Kuka robot datasheet © Kuka AG 2016

Kuka robot ride recording: Video © Youtube user Iain Hendry, 2009

Axes pictures © YouTube user thegeekgroup, 2016. (CC BY) 3.0

Images of robot taken apart © YouTube user thegeekgroup, 2016. (CC BY) 3.0

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References

5 Accuracy and Calibration

Kuka robot: Photo © Kuka AG 2013

Image of servomotor assembly © Kollmorgen. All Rights Reserved

Graph of servomotor speed vs. torque © 2016 ORIENTAL MOTOR U.S.A. CORP. All

Rights Reserved.

Harmonic drive gear components: M. MasoumiH. Alimohammadi, An investigation into

the vibration of harmonic drive systems, Frontiers of Mechanical Engineering, 2013, Vol.

8, Issue 4, 409-419; Copyright 2014, The Institution of Engineering and Technology

Harmonic drive gear schematic drawing Image © Keiji Ueura, Rolf Slatter, "Development

of the Harmonic Drive Gear for Space Applications", ESMATS 1999

Microscope cam: Photo © John Hart. Used with permission.

Laser tracker calibration video Video © FARO Technologies / Youtube user FAROGB,

2013

Laser robot tracking schematic: Image © FARO Technologies

FARO laser tracker Image © FARO Technologies

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References

Corner cube retroreflector schematic: Image by User: chetvorno on Wikimedia. This work

is in the public domain.

Faro SMR: Image © FARO Technologies

Fanuc display at IMTS 2016: Photo © John Hart. Used with permission.

Fanuc vibration compensation schematic: Image © FANUC America Corporation

Four Fanuc robots welding shaft: Image © FANUC America Corporation

Boston Dynamics humanoid robots: Image © Boston Dynamics 2016

6 Scara, Delta, and Gantry Robots

Scara robot workspace: Sciavicco, L.; Siciliano, B. Modelling and Control of Robot

Manipulators; Advanced Textbooks in Control and Signal Processing; Springer London:

London, 2000; Burckhardt C. Industrial Robots : Proceedings = Robots Industriels :

Comptes Rendus = Industrie-Roboter: Tagungsberichte [e-book]. Basel : Birkhauser

Verlag, 1975

Old Kuka scara robot: Photo © Kuka AG

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References

Epson scara robot: Photos Copyright © 2000-2016 Epson America, Inc., All Rights

Reserved

Delta kinematic: Image © Robert Williams, Ohio University, 2016

Adept Quattro S650h delta robot: Image © OMRON ADEPT Technologies Inc

Flexpicker delta robot pankaces pick'n'place demo © Andrew Jones, 2009, via YouTube

Flexpicker delta robot salami pick'n'place demo: Video © ABB / Youtube user

ABBRobotics, 2010

Gantry machine: Image © ATERA MANUFACTURERS GROUP, S.A.

Conventional mill: Photo © John Hart. Used with permission.

Gantry schematic: Sciavicco, L.; Siciliano, B. Modelling and Control of Robot

Manipulators; Advanced Textbooks in Control and Signal Processing; Springer London:

London, 2000; Burckhardt C. Industrial Robots : Proceedings = Robots Industriels :

Comptes Rendus = Industrie-Roboter : Tagungsberichte [e-book]. Basel : Birkhäuser

Verlag, 1975

Harbour freight gantry: Photo Courtesy of Newport News Shipbuilding of the U.S. Navy.

This work is in the public domain.

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References

OMAX Waterjet: Image © OMAX 2010

FDM printer: Photos © UIC 2015 via YouTube

Seamco cartesian robot: Image © Seamco NV

Single-point metal forming video screenshots: Screenshots © 2016 SAE International. All

rights reserved.

7 Gripping and Manipulators

Robotiq grippers: Image © Robotiq 2016

Schmalz vacuum grippers: Image © J. Schmalz GmbH 2016

Nachi IMTS 2016 exhibit: Photo © John Hart. Used with permission.

Robotics vs human labor by industry: Copyright © 2016; The Boston Consulting Group.

All rights reserved

Start Wars image of humanoid robots: Image © Disney

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References

Amazon Picking Challenge screenshots screenshots from Amazon Picking Challenge

2016; © Copyright 2016 IEEE — All rights reserved.

Google Research Blog: Deep learning for robots: Screenshots © Google Research Blog

2016

Rethink Robotics Baxter montage video Video © 2008–2016 Rethink Robotics. All rights

reserved.

Baxter IMTS 2016 exhibit: Photo © John Hart. Used with permission.

Google Research Blog: Deep learning for robots: Screenshots © Google Research Blog

2016

Rethink Robotics Baxter montage video Video © 2008–2016 Rethink Robotics. All rights

reserved.

Baxter IMTS 2016 exhibit: Photo © John Hart. Used with permission.