ROBOTICS COURSE NOTES©1981, 1991, 2001, 2011, 2020 Max Donath(Incorporates material from many sources)

DEPARTMENT OF MECHANICAL ENGINEERINGUNIVERSITY OF MINNESOTA

111 CHURCH ST. S.E. MINNEAPOLIS, MN 55455

ME5286 Robotics Topics (1st 9-10 weeks):

v Manipulator specifications and criteria for selectionv - Resolution, repeatability, and accuracyv Manipulation task componentsv Mathematics of coordinate transformationv Homogeneous transformations matricesv Inverse kinematics: The problemv Robot link transformation matricesv Inverse kinematic solutionsv Velocity and path control: the Jacobianv Computation of the Jacobianv Task primitives and programming: Computational aspectsv Determining path trajectoriesv - Interpolation and spline functionsv Static force analysis: Another role for the Jacobianv Manipulator dynamicsv Inertial effects of drive and transmissions on dynamicsv Force based control

- Force vs. impedance control vs. position controlv Manipulator peripherals: the Remote Center Compliancev Integrating sensors into robots

Collaborative robots (Cobots) used in lab

v Cobots don’t require protective cagesv Incorporate force and torque sensing in order to prevent

injury to adjacent humans

See http://www.me.umn.edu/labs/robotics/index.shtml

Laboratory:

v Students work in pairs and perform a series of experiments and then assemble a flashlight using the Universal Robots UR5 robot.

v Access to several programming environments allows students to program the robot off-line and then use that code for carrying out specified tasks during the lab session.

v Laboratory modules will require BOTH written submissions on scheduled dates (to be announced) and a one-time “oral” presentation during which the student will demonstrate the robot assembling a flashlight.

v Students will be assigned a partner and a weekly 2-hour time slot to perform the lab.

Image Processing (computer vision) topicsLast 5 weeks

v Imaging fundamentals and sensors- Image formation- Camera fundamentals, digitization- Digital image representation, color fundamentals

v Image processing methods- Spatial domain transformation, image enhancement, histogram

equalization- Edge detection techniques- Hough and generalized Hough transform,

line detection- Point of interest detection, corner detection- Deep learning

v Applications

Scheduling and gradingv Lectures:

Tuesdays and Thursdays: 8:00am – 9:55am, ME2124 lecture periods per week of which one will often be used to discuss the lab.

v Labs: 2 hours per week(1st 10 weeks). Schedule by filling inhttps://forms.gle/WzVrWPj9YhTvJpbh7

v Grading: 4 credits:– Robotic manipulator portion of class

– 2 In-class ‘open-book’ quizzes: 15% each;– Lab reports and demonstration of robot performing

assembly: 40% total– Computer vision portion of class – 3 Software Assignments:

30%

Robots on BMW's Assembly LineAt BMW’s South Carolina plant, robots work side-by-side with human workers, making the assembly line more cost-effective and productive. See 3 minute video at:https://www.asme.org/engineering-topics/media/automotive/video-robots-bmws-assembly-line

Also see article “Smart Robots Can Now Work Right Next to Auto Workers” (Sep-17-2013)http://www.technologyreview.com/news/518661/smart-robots-can-now-work-right-next-to-auto-workers/

And article “Manufacturers adopt robots that help human workers, not replace them” (Oct-18-2018)https://www.chicagotribune.com/business/ct-biz-cobots-manufacturing-replace-human-workers-20181010-story.html

Collaborative robots• Robots don’t require protective cages• Incorporate force and torque sensing in order to prevent

injury to adjacent humans

Robotics TechnologyMotivation: Replacement for limited function while maintaining �human� flexibilityv Manufacturing

Discrete ContinuousFlexible VS Hard Automation Transfer LinesBatch High Volume

ØHybrid circuit assemblyØ3D Printing

v Hazardous EnvironmentsØ SpaceØ UnderwaterØ RadioactiveØ ToxicØ Combat

v MedicalØ MicrosurgeryØ Rehabilitation

§ Upper extremity§ Lower Extremity

v Transportation

IN 1984:THE UNITED STATES MANUFACTURED 5500 ROBOTSVALUED AT $300 MILLION (1984 DOLLARS)

SOURCE: FIRST ROBOT CENSUS, AUGUST, 1985NATIONAL CENSUS BUREAU(AS REPORTED BY CNN, AUGUST 18, 1985)

IN 1985:ROBOTS VALUED AT $443 MILLION WERE SHIPPED.

IN 1995:10,198 UNITS VALUED AT $897.7 MILLION WERE SHIPPED.ROBOT SHIPMENTS MORE THAN DOUBLED SINCE 1991.

IN 2005: 18,228 ROBOTS WERE SOLD.

SOURCE: ROBOTICS INDUSTRY ASSOCIATION (RIA), ANN ARBOR, MI

As of Feb. 28, 2019, according to the Robotic Industries Associationw“Robots shipped to North American companies in record numbers in 2018, with more non-automotive companies installing robots than ever before. Statistics show 35,880 units were shipped in 2018, a 7% increase over 2017, with 16,702 shipments to non-automotive companies, up 41%. Notable growth came in areas like food and consumer goods (48%), plastics and rubber (37%), life sciences (31%), and electronics (22%).”

w“… Meanwhile, shipments to the automotive industry slowed, ….

w“… sales and shipments aren’t just to large, multinational companies anymore. Small and medium-sized companies are using robots to solve real-world challenges, which is helping them be more competitive on a global scale.”

MOST RECENT INDUSTRY STATISTICS CAN BE FOUND AT:http://www.robotics.org/Industry-Statistics

See https://ifr.orgfor more …

For IFR Report, Jan. 20, 2020, —https://ifr.org/ifr-press-releases/news/facts-about-robots-worldwide

From: M. Muro and S. Andes,Robots Seem to Be Improving Productivity, Not Costing Jobs,Harvard Business Review, June 15, 2015https://hbr.org/2015/06/robots-seem-to-be-improving-productivity-not-costing-jobs

From: M. Muro and S. Andes,Robots Seem to Be Improving Productivity, Not Costing Jobs,Harvard Business Review, June 15, 2015https://hbr.org/2015/06/robots-seem-to-be-improving-productivity-not-costing-jobs

Robots: State of the Art?

Genius

Gifted

High Normal

Normal

Low Normal

Moron

Imbecile

Idiot

100. . . . . . . . . .

0. . . . . . . . . . . .

STUPID BEHAVIOR

◆ HITTING OBJECTS INADVERTENTLY AND THEN DOING IT AGAIN

◆ PICKING UP OBJECTS THAT AREN’T THERE

◆ CONTINUING WITH OPERATIONS THAT MAKE NO SENSEE.G., INSERTING SQUARE PEGS INTO ROUND HOLES

◆ REQUIRING DETAILED INSTRUCTIONS

◆ ALBERT EINSTEIN ONCE DEFINED INSANITY AS:�DOING THE SAME THING OVER AND OVER AGAIN ANDEXPECTING DIFFERENT RESULTS.�

ROBOT REQUIREMENTS:

SENSORY INPUT

INTELLIGENCE

MOTOR FUNCTION

HUMAN SENSES:

VISION

HEARING

TOUCH

BALANCE

PROPRIOCEPTIONMUSCLE LENGTHMUSCLE TENSION

TEMPERATURE

SMELL AND TASTE

PAIN

Human Intelligence

Cerebrum Complex Decisions

Cerebellum Coordination

Spinal Reflex Activity

Increasing precision and speed but decreasing complexity

HUMAN GROSS MOTOR ACTIVITY:

POSTURELOCOMOTION

HUMAN FINE MOTOR ACTIVITY:

MANIPULATION

Cylindrical

Rectangular

Spherical

See video on course web siteUNDER Manipulators/Resources LINKhttp://me.umn.edu/courses/me5286/manipulator/resources.shtml

Cobots or Collaborative Robots

From https://en.wikipedia.org/wiki/Cobot

“A cobot or co-robot (from collaborative robot) is a robotintended to physically interact with humans in a shared workspace.

This is in contrast with other robots, designed to operate autonomously or with limited guidance, which is what mostindustrial robots were up until the decade of the 2010s.

Cobots were invented in 1996 by J. Edward Colgate and MichaelPeshkin, professors at Northwestern University.

A 1997 US patent filing describes cobots as "an apparatus and method for direct physical interaction between a person and a general-purpose manipulator controlled by a computer."

“The cobot's function was to allow computer control of motion, by redirecting or steering a payload, in a cooperative way with the human worker.”

A safety standard “ISO/TS 15066:2016, Robots and robotic devices -- Collaborative robots” was published in 2016. Seehttp://www.iso.org/iso/catalogue_detail?csnumber=62996

Yumi from ABB

Universal Robots

Baxter from Rethink Robotics (which closed in 2018)

FANUC CR-35iA Robot

Kuka LBR iiwa

Possible kinematic configuration ofthree-jointed robot manipulators

From: Eugene I. Rivin,�Mechanical Design of Robots�McGraw-Hill, 1988.

* Characterized by some degree ofredundancy (points in workspacecan be reached by at least2 sets of joint coordinates)

The SCARA {Selective Compliant Articulated Robot for Assembly}, see

http://products.omron.us/Asset/Omron-Adept-Cobra-s800_DS_EN_201602_R63IE01.pdf

https://en.wikipedia.org/wiki/SCARA

Parallelogram Robot Structure

Stewart Platforms

https://en.wikipedia.org/wiki/Stewart_platform

Hexapods

Many micropositioning applicationsSee http://www.pi-usa.us/products/Micropositioning_Stage_Hexapod/hexapod-6-axis-

stage.php

H-811 Miniature Hexapod 6-Axis Positioner

TYPES OF MANIPULATOR CONTROL

◆ POSITION

◆ VELOCITY

◆ PATH

◆ FORCE