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Dr Will Browne

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Title: Dr Will Browne


1
Dr Will Browne Co-author Dr Victor Becerra
Cybernetic Intelligence How Feedback Can Enhance
the Behaviour of Mobile Robotics
w.n.browne_at_reading.ac.uk Department of
Cybernetics The University of Reading Whiteknights
Reading UK 44 (0)118 378-6705
2
AcknowledgementsCybernetic Intelligence Research
Group
http//www.cirg.reading.ac.uk/ Cybernetic
intelligence is the study of intelligence and its
application. Considering theoretical,
mathematical and philosophical aspects of
consciousness and intelligence and their
application to the design of intelligent machines
and the control of complex systems
Becerra, Dr Victor Gasson, Mr Mark Goodhew, Mr
Iain Hong, Dr Xia Hutt, Mr Ben Lang, Mr Robert
Minchinton, Mr Paul Mitchell, Dr Richard Nasuto,
Dr Slawomir Warwick, Prof Kevin Wyatt, Mr Jim
3
Contents
  • Cybernetics
  • What is Cybernetics?
  • Robotic feedback
  • Robotic examples
  • Learning and intelligence
  • Steps towards intelligence

4
Cybernetics
  • Norbert Wieners definition (1948)
  • Control and Communication in the Animal and
    Machine
  • Combines information theory (Shannon), biological
    modelling (McCulloch), artificial intelligence
    (Von Neumann) and systems (Wiener).

5
Open loop
  • The output signal is Not fed back to the input
    signal.
  • Inputs System Outputs

6
Closed loop
  • The output signal is fed back to the input
    signal.
  • Inputs System Outputs

7
Feedback Loop
  • Open loop
  • Closed loop, feedback system

Input
Output
System
Error
Input
Output
System
_

Feedback
8
Prosthetics
  • Dr Peter Kyberd, formerly Southampton University
    and Now New Brunswick, Canada.
  • Sound sensors for slip detection

9
Cyborg
  • Professor Kevin Warwick, Micro array
  • Human in the loop

10
Mobile Robotics
  • Dr Susan Calvin obtained her bachelor's degree at
    Columbia in 2003 and began graduate work in
    cybernetics.
  • Asimov (1940)

11
7 Dwarf Robots
  • Several generations of small mobile robots

12
7 Dwarf Robots
  • Several generations of small mobile robots

13
7 Dwarf Robots
  • Several generations of small mobile robots

14
Rogerr
  • Marathon running robot designed to follow
    infrared beacon on the back of a lead runner
  • Too much feedback!

15
Science Museum Robots
  • Millennium wing of Science Museum, London.
  • Four programmed activities.
  • Follow
  • Pursuit and evasion
  • Flock
  • Simon says

16
Science Museum
  • Tested in laboratory conditions, that mimicked
    exhibition
  • Follow

17
Flock
  • avoid objects (most basic behaviour with highest
    priority),
  • if no other robots are visible become a leader
    and wander,
  • if in a flock try to maintain position,
  • if a flock can be seen in the distance, speed up
    and head towards it, with more priory being given
    to following the closest visible leader.
  • Must use a dynamic leader!
  • Communicate and feedback who is the leader.

18
Real Robots
  • Cybot from Seven Dwarfs
  • Eaglemoss parts work magazine
  • 4 million copies worldwide

19
Interactive R2-D2
  • Co-designed by Dr Dave Keating
  • Researched the original seven dwarfs
  • 200,000 robots worldwide
  • Uses motor feedback control in head and wheels

20
Morgui
  • Humanoid sensor fusion
  • Ultrasonic
  • Sound sensors
  • Vision
  • Infrared

21
Learning
  • Robots can learn from the interaction within an
    environment
  • Performance feedback can be provided (colliding
    with other objects is not rewarded highly!)
  • Reinforcement learning

22
Q-Learning
  • Look-up table of conditions (sensor readings) to
    desired actions (motor movements)
  • Single step example has 224 states, which is a
    very large look-up table
  • Fuzzy sets used to map the input space to five
    states
  • no object near robot,
  • obstacle in distance (gt 500mm) to the right,
  • obstacle in distance (gt 500mm) to the left,
  • obstacle relatively near (lt 230mm) the right,
  • obstacle relatively near (lt 230mm) the left.
  • Weighted roulette wheel technique selects
    randomly the most appropriate action for the
    situation given the current probabilities
  • Probability increased of successful action.

23
Difficult Learning
  • Latent learning
  • Rat maze experiments (Blodgett 1929 and Seward
    1949)
  • No immediate feedback of utility of the action.
  • Reinforcement learning algorithms must be adapted

24
Latent Learning
  • Latent learning has three stages
  • Robot (or Rat) enters the maze and explores it
    without reward.
  • Robot (or Rat) is then placed in one of the end
    zones (E,F) and given a reward
  • Robot (or Rat) is then placed at start (S) of
    maze and must navigate in the shortest path back
    to the reward state.

25
Latent Learning
  • Anticipatory Classifier Systems (Stolzmann 1999)
  • Showed latent learning in simulation
  • Difficulties in size of domain in real robots
  • Inaccuracies in feedback can cause fuzzy sets
    problems over time.

26
Latent Learning
  • Robots not very good at consistently turning at
    90
  • Latent learning environment simplified to
    N,E,W,S, compass points.
  • After a five-minute run a robot will start
    getting very close to one wall and will
    eventually get stuck against it!

27
Improved Learning
  • Humans will take actions in order to improve the
    quality of their feedback, not just the reward
    itself
  • Robots will need to learn to take actions that do
    not lead to a reward, but improve the certainty
    of the action to take.
  • Cybernetic principles (second order Cybernetics)
    will need to be applied.

28
Balancing Act
29
Learning Classifier Systems?
  • Evolutionary Computation
  • Rule form is Transparent,
  • (If...Then...)
  • Includes statistics about rule
  • (Rule Statistics Classifier)
  • Gain knowledge by experience or direct transfer
  • Draw correct conclusions from their own
    hypothesised knowledge
  • LCS are a quagmire - a glorious, wondrous and
    inventing quagmire, but a quagmire nonetheless
  • Goldberg et al.
    92

30
Learning Classifier Systems
INPUT KNOWN MILL DATA
Past
LEARNING CLASSIFIER SYSTEM
IF... THEN... (STRENGTH) RULES
Future
31
INPUT KNOWN MILL DATA
LEARNING CLASSIFIER SYSTEM
INITIAL RULE BASE
MATCH
ENCODING
INPUT
SELECT
TRAINING RULE BASE
EFFECT
OUTPUT
CREDIT
FINAL RULE BASE
DECODING
IF... THEN... (STRENGTH) RULES
32
INPUT KNOWN MILL DATA
LEARNING CLASSIFIER SYSTEM
INITIAL RULE BASE
MATCH
ENCODING
INPUT
PLAUSIBLY BETTER RULES GENERATED
SELECT
TRAINING RULE BASE
RULE DISCOVERY
EFFECT
OUTPUT
CREDIT
FINAL RULE BASE
DECODING
IF... THEN... (STRENGTH) RULES
33
Summary
  • Cybernetics considers feedback, systems and
    embodiment within an environment.
  • Understanding Cybernetics assists in the
    development of mobile robotics.
  • Robotics and principles of Cybernetics will
    continue to grow in importance.

34
The End
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