FROM IMPRINTING TO ADAPTATION: BUILDING A HISTORY OF AFFECTIVE INTERACTIONWritten by Arnaud J. Blanchard & Lola Canamero

Presented by James Bowden

DID YOU KNOW... Ducklings think the first thing they see is

their mother

This is what is meant by ‘Imprinting’

IMPRINTING The phenomenon where animals form special

attachments to objects which they are exposed to in early life

Allows animals to identify a ‘care giver’.

Not limited to birds

CONSIDERATIONS FOR AN IMPRINTING MODEL

Imprinting may not happen immediately after birth What if animal is blind at birth? What if there is no ‘mother’ to imprint?

What processes are involved? Attractiveness Familiar vs Novel

THE PERCEPTION-ACTION MODEL At all times there is a current perception and

a goal perception

Actions taken are a side effect of wanting to achieve the goal perception

At the start, the goal perception and current perception should be same

This demonstrates Imprinting

What if the is no care giver to imprint?

How can imprinting occur after ‘hatching’?

THE PERCEPTION-ACTION MODEL

Time (x)

Learning rate (y)

EXPERIMENT 1 Koala Robot

All inputs provided by infrared sensors

Has 3 actions Approaching: Attempts to reach the goal perception Following: Attempts to stay near the goal perception Avoids: Where a nearby presence has made the

goal perception another location

Expressed by accelerating and reversing

RESULTSGoal Near Goal Far

Velocity

Proximity(higher = closer)

Speed of response

Solid = Current Perception Dashed = Goal Perception

Top graphs Goal perception stabilises over time even though

the ‘imprinting stimulus’ moves at different distances in each experiment

Bottom graphs Changes match attempts to converge

ideal/cureent goals on the top graphs

This demonstrates an initial imprinting process

RESULTS

ADAPTION So far the only adaptation over time is the

decreasing learning rate

This prevents everything that has been learned at one point being replaced in the future

It is also important to consider how relevant a stimulus is

ASSESSING RELEVANCE In this paper, a stimulus’ relevance is

decided by the level of comfort it provides

For this experiment comfort is given by stimulating the robots left sensor

Learning rate still decreases over time but attachments are formed faster when comfort is high

MULTIPLE GOAL PERCEPTIONS The robot was also required to interact with a

stimulus while judging comfort levels

This would allow it to judge the comfort level of a stimulus

Different comfort to stimulus levels created the need for temporary goal perceptions, given certain circumstances

Known as Desired Perceptions

IMPLEMENTING ADAPTION (COMFORT)

Learning rate still tends to 0 but now it is modulated by 3 different levels of comfort

This poses the danger of an environment becoming too hostile for the robot to learn at all

Solved by modulating the learing rate by variation, rather than a fixed value

Desired perceptions are evaluated by storing recent comfort levels and seeking out previous states of ‘happiness’ when an environment suddenly becomes hostile.

The new goal perception therefore becomes a combination of desired perceptions

IMPLEMENTING ADAPTION (DESIRES)

EXPERIMENT 2

Point in time = a (i.e. 0)

The robot is alone at initialisation

Comfort: static

Reaction: none

EXPERIMENT 2

Point in time = b

The robot is approached by a human

Comfort: decreases

Reaction: Avoids (i.e. Reverses away)

EXPERIMENT 2

Point in time = c

The robot is comforted by the human

Comfort: increases

Reaction: Robot no longer reverses

EXPERIMENT 2

Point in time = d

The human stops comforting the robot

Comfort: decreases

Reaction: Robot ‘explores’ to find a previous state in which it was happier (goal perception)

RESULTS

The robot has become less apprehensive of unknown objects as it’s previous experience has taught it that they provide comfort.

MY CONCLUSIONS OF THIS PAPER Some interesting concepts of adaption but

few specifics

Specific models/implementation are incredibly simplified

Lacks different comfort sources E.g. Food, warmth,

Overall the epigenetic model exists but lacks detail in implementation