All Teams Overview:

1
All Teams Overview
Team Topics
1 Overview Chapter 1 From Teleoperation to Autonomy Chapter 2 The Hierarchical Paradigm
2 Chapter 3 Biological Foundations of the Reactive Paradigm Chapter 4 The Reactive Paradigm Chapter 5 Designing a Reactive Implementation
3 Chapter 7 The Hybrid Deliberative/Reactive Paradigm
2
Team 1 Overview
Name Presents section of Book
Jorge Franco Introduction and Overview
Willmert Pereyra What is a robot and brief history 1.1 1.4.1
George Ragousis Robot Control and Operation 1.4.2 1.7
Sylvester Delano GPS Strips 2.1 2.2.3
Alexander Torres NHC NIST RCS 2.2.4 2.7
3
Introduction and Overview

• Jorge Franco

4
Overview

• What is AI robotics
• 3 major paradigms
• Ways in which intelligence is organized
• Architectures for paradigms
• Coherent
• Reusable
• Single/Team of robots

Implementations
5
What are Robots?

• Connotation/denotation
• anthropomorphic
• Origins on January 25, 1921, Prague, Karel
  Capeks play, R.U.R (Rossums Universal Robots)
• Term derived from Czech word robota, loosely
  translated as menial worker.
• Attitude towards robot has disastrous
  consequences
• Moral of rather socialist story Work defines a
  person

6
What are Robots? (contd)

• Shift from human-like servants made from
  biological parts to human-like servants made up
  of mechanical parts due to science fiction
• Classics
• Metropolis (1926), The Day the Earth Stood Still
  (1951), and Forbidden Planet (1956)
• Shift from human-like mechanical creatures to
  whatever shape gets the job done is due to
  reality
• Definition used in book an intelligent robot is
  a mechanical creature which can function
  autonomously.

7
What are Robotic Paradigms?

• A paradigm is a philosophy or set of assumptions
  and/or rules/techniques which characterize an
  approach to a class of problems
• Why know paradigms?
• Key to successfully program a robot for an
  application
• Interesting from historical perspective
• Issues that spawned one the shift from one
  paradigm to another
• 3 kinds
• Hierarchical
• Reactive
• Hybrid deliberative/reactive
• Described in two ways
• Relationship between 3 accepted primitives
• Sense, Act, Plan
• Way that sensory data is processed and
  distributed through the system

8
Robot Paradigm Primitives(fig1.2 from book)
Robot Primitives Input Output
Sense Sensor data Sensed information
Plan Information (Sensed and/or cognitive) Directives
Act Sensed information/ directives Actuator commands
9
Sensing Organization in Robot Paradigms

• Way Sensory data
• Processed
• Distributed
• Local processing
• Sensor information restricted to
  specific/dedicated way for each robot function
• Global world model processing
• All SI first processed into a global world model
• Subsets of model distributed to other functions
  as needed

10
Overview of the 3 Paradigmsfig.1.3 a.)
Hierarchical, b.) Reactive, and c.) Hybrid
deliberative/reactive
11
Hierarchical Paradigm

• 1967 1990
• Top down fashion Heavy on planning
• Introspective view
• However as Cognitive Psych. now know
• Not always good assessment of thought process.
• Default schemas or behaviors
• Global world model
• Hard and brittle
• Frame problem and closed world assumption

12
Another View of the Hierarchical Paradigm
(fig.1.4 from book)
Robot Primitives Input Output
Sense Sensor data Sensed information
Plan Sensed and/or cognitive information Directives
Act Sensed information/ directives Actuator commands
13
The Reactive Paradigm (fig.1.5 from book)
Robot Primitives Input Output
Sense Sensor data Sensed information
Plan Sensed and/or cognitive information Directives
Act Sensed information/ directives Actuator commands
14
The Hybrid Deliberative/Reactive Paradigm
(fig.1.6 from book)
Robot Primitives Input Output
Plan Information (Sensed and/or cognitive) Directives
Sense-Act (behaviors) Sensor data Actuator commands
15
Representative Architectures

• Templates for an implementation
• Examples of what each paradigm really means
• According to Mataric an architecture is a
  principled way of organizing a control system,
  with constraints on the way the control problem
  can be solved
• Common components in robot architecture and rules
  of thumb for placing them together
• IC car paradigm
• Each car manufacturer has its own architecture
• The car manufacturers may have slight
  modification on their architecture for sedans,
  convertibles, SUVs,etc.

16
Set Criteria for the Evaluation of an Architecture

• Modularity
• Niche Targetability
• Portability
• Robustness

17
Layout of the Section

• Divided into 8 chapters
• 1. define Robotics
• 2. describes Hierarchical Paradigm and 2
  architectures
• 3. sets the stage for understanding the Reactive
  Paradigm and the motivation that spawned it.
• 4. Describes the Reactive Paradigm and popular
  architecture
• 5. Provides guidelines and case studies on
  designing robot behaviors
• 6. Discusses simple sonar and computer vision
  processing techniques
• 7. Describes the Hybrid Deliberative-Reactive
  Paradigm
• 8. Discusses how the principles of the 3
  paradigms have been transferred to team of robots

18
Sections 1.1 1.4.1

• Willmert Pereyra

19
Uses of Robots

• Dirty jobs.
• Dull jobs.
• Dangerous jobs.

20
Robotics Timeline
Planetary rovers
AI robotics
vision
Telesystems
Industrial manipulators
manufacturing
Telemanipulators
1960
1970
1980
1990
2000
21
Old Movies About Robots

• Modern Times (Charlie Chaplin), 1936.
• Metropolis, 1927.
• Silent Running, 1972.
• The Phantom Menace, 1999.

22
Modern Times 1937
23
Metropolis 1927
24
Silent Running 1972
25
The Phantom Menace 1999
26
Approaches to Robotics

• Artificial Intelligence (AI).
• Engineering.

27
AI vs. Engineering

• AI
• Uses paradigms.
• All actions are human-like.
• Engineering
• Does not use paradigms.
• Actions performed are mechanical.

28
Engineering Control Types

• Ballistic control
• The position, trajectory and velocity profiles
  are computed once.
• Feedback control
• The error between the goal and current position
  is noted by a sensor(s) a new trajectory and
  profile is computed and executed. Then modified
  in the next update.

29
AI Robotics Terms

• Intelligent Robot
• A mechanical creature which can function
  autonomously.
• Paradigm
• A philosophy or set of assumptions and/or
  techniques which characterize an approach to a
  class of problems.

30
AI Robotics Terms

• Luddites
• People who object to robots, or technology in
  general.
• Artificial Intelligence (AI)
• (1) Science of making machines act intelligently.
  (2) The study of ideas that enable computers to
  be intelligent. (3) An attempt to make computers
  do things that at present people are better at.

31
AI Robotics Terms

• Teach pendant
• A device that enables the programmer to guide the
  robot through the desired set of motions.
• Automatic Guided Vehicle (AGV)
• A vehicle that knows where it is, can plan a path
  from its current location to its goal destination
  and can avoid colliding with obstacles.

32
AI Robotics Terms

• Telepresence
• The reduction of cognitive fatigue and simulator
  sickness by making the human-robot interface more
  natural virtual reality.
• Telemanipulator
• Sophisticated mechanical linkage which translates
  motions on one end of the mechanism to motions at
  the other end.

33
AI Robotics Terms

• Industrial manipulator
• A reprogrammable multifunctional mechanism that
  is designed to move materials, parts, tools, or
  specialized devices.
• Black factory
• A factory that has no lights turned on because
  there are no workers.

34
Architecture Evaluation Criteria

• Support for modularity
• Good software engineering principles?
• Niche targetability
• Works well for the intended application?
• Ease of portability
• Works for other applications or other robots?
• Robustness
• Is the system vulnerable? Where?

35
Model S Telemanipulator

36
Model S Telemanipulator

37
Movemaster Robot

38
Industrial Robots

39
Robotic Paradigms

1. Hierarchical.
2. Reactive.
3. Deliberative/Reactive.

40
Defining Paradigm Assumptions

• By the relationship between the primitives.
• By the way sensor data is processed and
  distributed.

41
Global World Model Problems

• Constructing generic global world models is very
  hard due to the frame problem and the closed
  world assumption.

42
Global World Model Problems

• Frame problem
• Deals with the representation of real-world
  situations in a way that is computationally
  tractable.
• Closed/Open world assumption
• States that the world model contains everything
  the robot needs to know (Closed) and if it is
  violated the robot may not be able to function
  correctly.

43
Hierarchical Paradigm

• Oldest paradigm.
• Prevalent from 1967-1990.
• Robot operates top-down.
• Emphasizes planning.
• Assumes thought is introspective.
• A global model captures all sensing data.

44
Hierarchical Paradigm
Primitives Input Output
Sense Sensor data Sensed information
Plan Sensed and/or cognitive information Directives
Act Sensed information/ directives Actuator commands
45
Hierarchical Paradigm
46
Robot Control and Operation Section 1.4.2 1.7

• George Ragousis

47
4 Ways to control and operate a robot

• 1. Remote control (RC)
• 2. Tele-operation
• 3. Semi-autonomous
• 4. Autonomous (AI)

48
1. Remote control

• you control the robot
• you can view the robot and its relationship to
  the environment
• operator isnt removed from scene, not very safe
• ex. radio controlled cars, bomb robots
• Boxing RC robots ?

49
2. Teleoperation

• you control the robot
• you can only view the environment through the
  robots eyes
• dont have to figure out AI

50
2. Teleoperation

Local
Remote
51
2. Teleoperation

• is suitable for applications where
• the tasks are unstructured and not repetitive
• the task workspace cannot be engineered to permit
  the use of industrial manipulators
• key portions of the task require dexterous
  manipulation, especially hand-eye coordination,
  but not continuously
• key portions of the task require object
  recognition or situational awareness
• the needs of the display technology do not exceed
  the limitations of the communication link
  (bandwidth, time delays)
• the availability of trained personnel is not an
  issue

52
2. Teleoperation

• Disadvantages
• Cognitive fatigue, 100 guidance
• Simulator sickness
• communications bandwidth (telepresence)
• Time delays (Darkstar 1 Darkspot 0)

53
3. Semi-autonomous

• Portion of directions and commands is given to
  robot
• 2 flavors
• Shared control Control trading
• step by step instructions commanding
  robot to do something
• to accomplish task but no within its
  abilities and allowing the
• full guidance is required robot to get it
  done without interaction

54
4. Autonomous

• Auto nomous
• auto self
• nomos rule self-commanded
• space robotics
• the need for autonomy
• artificial intelligence (AI)

55
Teleoperation Vs Autonomous remote operation Vs
self operation

• much more difficult to achieve
• higher risk of misjudgment and false actions from
  robot
• no time delays in operation
• independent
• goal of autonomy and AI
• To mimic the capabilities of animals or humans
  sufficiently in order to survive for long periods
  with only simple instructions from earth.

• easy to achieve
• human in control small chances of decision and
  judgment errors
• dexterous manipulations
• critical decisions by human (Mars Pathfinder
  accident)
• Introduces time delays in proportion with the
  distance between local remote.

56
Artificial Intelligence

• Seven areas
• Knowledge representation how am I me?
• Understanding natural language (willing spirit
  weak flesh)
• Learning
• Planning problem solving
• Inference just take a decision
• Search
• Vision

57
Section 2.1 2.2.3

• Sylvester Delano

58
The Hierarchical Paradigm

• Describe the Hierarchical Paradigm in terms of
  the 3 robot primitives and its organization of
  sensing
• Name and evaluate one representative Hierarchical
  architecture in terms of support for modularity,
  niche targetability, ease of portability to other
  domains, robustness
• Understand precondition, closed world assumption,
  open world, frame problem
• List two advantages and disadvantages of the
  Hierarchical Paradigm

Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
59
Organization
Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
60
Stanford Research Institute

• SRI is an independent, non-profit research
  institute conducting client-sponsored research
  and development for government agencies,
  commercial businesses, foundations, and other
  organizations.
• SRI is well known for its innovations in
  communications and networks, computing, economic
  development and science and technology policy,
  education, energy and the environment,
  engineering systems, pharmaceuticals and health
  sciences, homeland security and national defence,
  and materials and structures.

61
Shakey

• The first mobile robot to be able to reason about
  its own actions, Shakey combined research in
  robotics, artificial vision, and natural language
  processing.
• Built by SRI (Stanford Research Institute) for
  DARPA 1967-9

Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
62
Shakey(cont'd)

• Programming was primarily in LISP.
  
• Used Strips as main algorithm for controlling
  what to do

63
What is LISP(LIST Processing) ?

• A high-level programming language used for
  developing AI applications. Developed in 1960 by
  John McCarthy, its syntax and structure is very
  different from traditional programming languages.
  For example, there is no syntactic difference
  between data and instructions.
  
• LISP is available in both interpreter and
  compiler versions and can be modified and
  expanded by the programmer. Many varieties have
  been developed, including versions that perform
  calculations efficiently.

64
Strips Means-ends analysis
Go to Stanford AI Lab
Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
  INITIAL STATE Tampa, Florida (0,0)
GOAL STATE Stanford, California (1000,200)
Difference 1020 miles
65
Difference Table
 
dlt200 miles
FLY
Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
100ltdlt200
TRAIN
dlt100
DRIVE
modedifference_table(INITIAL STATE, GOAL STATE,
difference)

1. Look up what to do FLY
2. Not at SAIL, so repeat
3. Look up what to do DRIVE

66
Preconditions
Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
dlt200 miles
FLY
100ltdlt200
TRAIN
dlt100
DRIVE (rental)
 
DRIVE (personal car)
 
How do I know if Im at the airport or at
home? Now must keep up with the state of the world
67
Maintaining State of the WorldAdd and Delete
Lists
 
 
Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
dlt200 miles
FLY
 
100ltdlt200
TRAIN
 
dlt100
DRIVE (rental)
at airport
 
 
 
DRIVE (personal)
at home
 
 
 
 
68
Class Exercise
 
Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
 
69
Strips Summary

• Designer must set up
• World model representation
• Difference table with operators, preconditions,
  add delete lists
• Difference evaluator
• Strips assumes closed world
• Closed world world model contains everything
  needed for robot (implication is that it doesnt
  change)
• Open world world is dynamic and world model may
  not be complete
• Strips suffers from frame problem
• Frame problem representation grows too large to
  reasonably operate over

Organization -SPA -global Strips -Shakey Rep.
Arch. -evaluation -NHC -RCA Summary
70
Section 2.2.4 2.7

• Alexander Torres

71
Team One Hierarchy STRIPS Summary

• Designer must set up
• World model representation
• Difference table with operators, preconditions,
  add delete lists
• Difference evaluator
• Strips assumes closed world
• Closed world world model contains everything
  needed for robot (implication is that it doesnt
  change)
• Open world world is dynamic and world model may
  not be complete
• Strips suffers from frame problem
• Frame problem representation grows too large to
  reasonably operate over

72
Team One Hierarchy Closed World Assumption and
the Frame Problem
It is impractical for a programmer to come up
with all possible reactions, conditions to all
probable cases in the real world The need to
formally represent the world and then maintain
every change about it is nonnutritive. The
axioms (facts) that would frame the world would
quickly become too numerous for any realistic
domain A proposed solution was ABStrips which
divided the problem into multiple layers of
abstraction (this would mean solving problems
with increasing levels of details)
73
Team One Hierarchy Nested Hierarchical
Controller (NHC)

• Representative Architecture
• Nested Hierarchical Controller (NHC)
• SENSE
• PLAN
• ACT
• The robot gathers observation from its sensors
  and combines that information with priori
  knowledge to create the World Model.
• From the World Model, the robot can PLAN what
  action it should take.

74
Team One Hierarchy Nested Hierarchical
Controller (NHC)
Representative Architecture Planning for
navigation consists of three step executed by
Mission Planner, Navigator, and Pilot Each of
these can access the World Model The last step
is the Pilot module generating specific actions
for the robot to do.
75
Team One Hierarchy Nested Hierarchical
Controller (NHC)

• The Benefits of the NHC are
• Unlike STRIPS it interleaves planning and acting
• It can adapt to changes in its environment if
  necessary
• The Disadvantages of NHC are
• Planning Function is only appropriate for
  navigation tasks

76
Team One Hierarchy NIST REAL Time Control
System RCS
Real-time Control System Architecture Created by
Jim Albus Best suited for semi-autonomous
control Based on NHC, RCS is developed as a
guide for manufacturers who wish to add AI to
their robots. Sensory perception modules
introduce a useful preprocessing step between the
sensor and the fusion into a world model The
Value Judgment module simulates the plan to
ensure they work. Behavior Generation Module
operates similar to the pilot with less focus on
navigations.
77
Team One Hierarchy Advantages and Disadvantages

• Advantage
• Provides an ordering of the relationship between
  sensing, planning, and acting.
• Disadvantages
• Planning, every update cycle the robot would have
  to update a global world model and do some type
  of planning.
• Sensing and action are disconnected. This doesnt
  allow for reflexive reactions found in real life.
• Dependence on global world model is related to
  the frame problem. A simple task can becomes
  incredibly complicated to describe.
• Uncertainty in semantics, sensor noise and
  actuator errors.

78
Team One Hierarchy Programming Considerations

• Predicate logic and recursion used by STRIPS
  favors languages such as LISP and PROLOG
• Although LISP and PROLOG do not have good
  real-time control properties, the alternative at
  the time was FORTRAN IV which did not support
  recursion
• Hierarchical Paradigm forces programming for
  specific tasks instead of object oriented tasks.
• NHC and RCS decomposition of a task is not
  modular in design

79
Team One Hierarchy Summary

• Except for NIST Real-time Control Architecture,
  Hierarchical Paradigm has fallen out of favor for
  more biologically based systems of control.
• It has contributed concepts and terminology such
  as preconditions, closed/open world assumptions,
  and the frame problem
• It has the inherent property to allow an
  evolution of intelligence from semi-autonomous
  control to full autonomy.