Introduction to Robotics

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Introduction to Robotics
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What is a Robot?

• Robot derives from the Czech word robota
• forced labor slavery
• Robot Industry Association
• A re-programmable, multi-functional manipulator
  designed to move material, parts, tools, or
  specialized devices through variable programmable
  motions for the performance of a variety of tasks
• Working definition
• physical agent that has an intelligent
  connection between sensors and actuators

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Fact and Fantasy
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Two Major Types of Robots

• Industrial Robots
• Operates in a stable and known environment
• Fixed or limited mobility
• Relatively simple control program
• Mobile Robots
• Operates in the real world
• Mobile!
• Requires a high degree of autonomy

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ASEA IRB L6/2(Industrial)

• Description
• Industrial Robot
• Five axis
• Payload of 13 lbs
• Repeatability .2mm
• Horizontal reach 1229mm
• Used for
• Part handling
• Tool manipulation
• Assembly

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Athlete Robot(Mobile)

• Description
• Mobile Robot
• 6-DOF legs
• Payload of 450 kg
• Used for
• Moving payloads across rough terrain

http//www-robotics.jpl.nasa.gov/systems/system.cf
m?System11
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Why Robots?

• The 3 Ds
• Dirty
• Dull
• Dangerous

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Focus This Semester

• AI as applied to Robotics
• Control Paradigms
• Behavior-based systems
• Knowledge Representation
• Sensing
• Multi-robot Systems
• Path planning/Navigation

Algorithm development, software design, and
artificial intelligence techniques as applied to
the study of Robotics
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What we wont focus on

• Kinematics/Dynamics
• Basic algorithms and data structures some
  coverage
• A mechanical engineering approach
• Traditional Control
• PID feedback no coverage
• Sensors and electrical subsystems some coverage
• An electrical engineering approach
• Cognitive Sciences
• HCI systems no coverage
• A psychological approach

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Robot Applications

• Manufacturing
• Dangerous Environments
• Cleaning pipes/pools
• Rescue robots
• Nuclear power plants
• Underwater recovery
• Home Robots
• Lawn mowing
• Vacuum cleaning

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Rescue Robots
A team of researchers from USF took robots to the
WTC to assist in the search-and-rescue mission
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Home Robots
http//video_demos.colostate.edu/robotics/index.ht
ml
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Primitive Robotic Functions

• SENSE
• The function of acquiring information from the
  environment
• bump sensors, optical sensors
• PLAN
• The function of determining high-level tasks to
  accomplish
• Various AI techniques
• ACT
• The function of producing low-level actuator
  commands
• Turn on motor one for .5 seconds

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Basic Issues in Robotics

• How to SENSE
• How to PLAN
• How to ACT

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Robotic Paradigms

• Paradigm
• A philosophy or set of assumptions which
  characterize an approach to solving a class of
  problems
• Hierarchical (1967 1990)
• Top-Down/Closed World/Monolithic/Global
  Data/Plan-based
• Reactive (1988 1992)
• Bottom-Up/Simple primitive acts/Open World/No
  Planning/Emergent Behavior
• Hybrid deliberative/reactive (1992-Present)
• Combination of above two approaches

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What are Robots Made Of?

• Sensors
• cameras
• ranged finders
• touch sensors
• Computer
• embedded controller and microprocessor
• Actuators
• wheels or legs
• manipulators (gripper or hand)

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Inchy the Robot

• Autonomous 1 inch robot
• Three NiMH batteries give 20 minute life
• Two synchronous 5mm motors
• Four infrared proximity sensors

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Jemmy the Robot

• Autonomous 1 inch robot
• Embedded PIC controller
• Two synchronous 3mm motors
• Four passive infrared sensors
• Winner of the International Microbot Maze Contest
  in 1997

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A Brief History of Robotics

• 1940s
• First remove manipulators for hazardous
  substances
• 1950s
• Industrial manipulators
• Closed loop control (an electrical engineering
  approach)

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A Brief History of Robotics

• 1955
• AI techniques are discovered
• 1960s
• Manufacturing robots
• Automatic guided vehicles
• Precise, repeatable movement
• 1970s
• Planetary landers
• Machine vision expands

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A Brief History of Robotics

• 1980
• Black Factory
• First AI robot Shakey
• 1985
• Reactive based robotics emerge
• 1990s
• Hybrid reactive/deliberative

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1953 Gray Walters Tortoise

• Light-seeking robot
• Go toward weak light
• Go away from strong light
• Rechargeable battery

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1953 Gray Walters Tortoise

• Steering motor on front wheel
• Driving motor on rear wheels
• Two vacuum tubes for control
• One photocell
• One bump sensor

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The Hierarchical Paradigm(The classical AI
approach)

• The components are FUNCTIONS
• Perception
• Learning
• Planning
• Sense-Plan-Act
• Interpret the sensors
• Model the world
• Plan
• Execute the plan

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Shakey (1967)

• First AI robot
• Used STRIPS planning system
• Also used first-order logic theorem prover

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Reactive Paradigm(The behavior based approach)

• The components are BEHAVIORS
• Avoid obstacles
• Explore
• Follow light
• Reflexive control
• Each behavior model is a reflex agent that
  directly maps sensed input to output
• Some type of high-level resolution mechanism is
  used if behaviors conflict

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Breitenberg

• Valentino Breitenberg (1984) developed his
  Breitenberg Vehicles
• Purely reactive systems
• Excitatory sensors () and Inhibitory sensors (-)

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Hybrid Systems

• Reacts when it can and plans when it must
• Most modern robots utilize this paradigm

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Basic Issues in AI

• Learning
• The ability to adjust behavior from examining
  past history
• Planning/Problem Solving
• Given information about the environment, what do
  I do?
• Inference
• Gaining information from incomplete data
• Natural language
• Understand spoken commands
• Knowledge Representation
• Data structures to represent information and
  support reasoning
• Search
• Efficient search of available actions to
  determine the best one
• Computer Vision
• Interpret information contained in a rasterized
  digital image

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DARPA Challenge

• DARPA conducted a challenge of autonomous ground
  vehicles between Los Angeles and Las Vegas in
  2005. A cash award of 2 million was granted to
  the first vehicles to complete the route within
  the specified (10 hour) time limit. No human
  intervention was allowed once the race begins!

• The vehicles will use a combination of
• GPS
• Laser range finders
• Radar

http//www.grandchallenge.org/
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The Republic

• The ill-fated ship was en route from New York to
  New Orleans when it sunk on October 25, 1865,
  during a hurricane near Savannah, Georgia. Its
  cargo included some 20,000 20 gold pieces, which
  were to help fund post-war Reconstruction. While
  the Republic's passengers were able to abandon
  ship, its precious cargo went to the bottom.
• Donald H. Kagin, author of Private Gold Coins and
  Patterns of the United States, has estimated that
  the treasure could be worth U.S. 120 million to
  180 million dollars.

Picture and text from National Geographic web
site http//news.nationalgeographic.com/ except
for above left which is from www.nytimes.com