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Why Robots may need to be self-‐aware, before we can really trust them
Alan FT Winfield Bristol Robo=cs Laboratory
Awareness Summer School, Lucca 26 June 2013
Outline
• The safety problem • The central proposi=on of this talk • Introducing Internal Models in robo=cs • A generic Internal Modelling architecture, for safety
– worked example: a scenario with safety hazards • Towards an ethical robot
– worked example: a hazardous scenario with a human and a robot
• The major challenges • How self-‐aware would the robot be? • A hint of neuroscien=fic plausibility
The safety problem
• For any engineered system to be trusted, it must be safe – We already have many examples of complex engineered systems that are trusted; passenger airliners, for instance
– These systems are trusted because they are designed, built, verified and operated to very stringent design and safety standards
– The same will need to apply to autonomous systems
The safety problem
• The problem of safe autonomous systems in unstructured or unpredictable environments, i.e. – robots designed to share human workspaces and physically interact with humans must be safe,
– yet guaranteeing safe behaviour is extremely difficult because the robot’s human-‐centred working environment is, by defini5on, unpredictable
– it becomes even more difficult if the robot is also capable of learning or adapta5on
The proposi=on In unknown or unpredictable environments, safety cannot be achieved without self-‐awareness
What is an internal model?
• It is an internal mechanism for represen=ng both the system itself and its environment – example: a robot with a simula5on of itself and its currently perceived environment, inside itself
• The mechanism might be centralized, distributed, or emergent
“..an internal model allows a system to look ahead to the future consequences of current ac=ons, without actually commiYng itself to those ac=ons” John Holland (1992), Complex Adap=ve Systems, Daedalus.
Using internal models
• Internal models can provide a minimal level of func5onal self-‐awareness – sufficient to allow complex systems to ask what-‐if ques=ons about the consequences of their next possible ac=ons, for safety
• Following Dennea an internal model can generate and test what-‐if hypotheses: – what if I carry out action x..?!– of several possible next actions xi, which should I choose?!
Dennea’s Tower of Generate and Test
Darwinian Creatures
Skinnerian Creatures
Popperian Creatures
Dennea, D. (1995). Darwin’s Dangerous Idea, London, Penguin.
Natural Selec=on
Individual (Reinforcement) Learning
Internal Modelling
Examples 1 • A robot using self-‐simula=on to plan a safe route with incomplete knowledge
Vaughan, R. T. and Zuluaga, M. (2006). Use your illusion: Sensorimotor self-‐ simula=on allows complex agents to plan with incomplete self-‐knowledge, in Proceedings of the Interna=onal Conference on Simula=on of Adap=ve Behaviour (SAB), pp. 298–309.
Examples 2
• A robot with an internal model that can learn how to control itself
Bongard, J., Zykov, V., Lipson, H. (2006) Resilient machines through con=nuous self-‐modeling. Science, 314: 1118-‐1121.
Examples 3
• ECCE-‐Robot – A robot with a complex body uses an internal model as a ‘func=onal imagina=on’
Marques, H. and Holland, O. (2009). Architectures for func=onal imagina=on, Neurocompu=ng 72, 4-‐6, pp. 743–759.
Diamond, A., Knight, R., Devereux, D. and Holland, O. (2012). Anthropomime=c robots: Concept, construc=on and modelling, Interna=onal Journal of Advanced Robo=c Systems 9, pp. 1–14.
Examples 4
• A distributed system in which each robot has an internal model of itself and the whole system – Robot controllers and the internal simulator are co-‐evolved
O’Dowd P, Winfield A and Studley M (2011), The Distributed Co-‐Evolu=on of an Embodied Simulator and Controller for Swarm Robot Behaviours, in Proc IEEE/RSJ Interna=onal Conference on Intelligent Robots and Systems (IROS 2011), San Francisco, September 2011.
A Generic IM Architecture for Safety
Internal Model Evaluates the
consequences of each possible next ac=on
Sense data
Actuator demands
The loop of generate and test
The IM is ini=alized to match the current real situa=on
Robot Controller The IM
moderates ac=on-‐selec=on in the controller
Copyright © Alan Winfield 2013
A Generic IM Architecture for Safety Sense data
Actuator demands
The loop of generate and test
Robot Controller
Robot Controller
Robot Model
World Model
Consequence Evaluator
Object Tracker -‐ Localiser
Copyright © Alan Winfield 2013
N-‐tuple of all possible ac=ons (a1, a2, a3, a4)
A Generic IM Architecture for Safety Sense data
Actuator demands
The loop of generate and test
Robot Controller
Robot Controller
Robot Model
World Model
Consequence Evaluator
Object Tracker -‐ Localiser
Copyright © Alan Winfield 2013
N-‐tuple of all possible ac=ons (a1, a2, a3, a4)
A Generic IM Architecture for Safety Sense data
Actuator demands
The loop of generate and test
Robot Controller
Robot Controller
Robot Model
World Model
Consequence Evaluator
Object Tracker -‐ Localiser
S-‐tuple of safe ac=ons (a3, a4)
Copyright © Alan Winfield 2013
A Generic IM Architecture for Safety Sense data
Actuator demands
The loop of generate and test
Robot Controller
Robot Controller
Robot Model
World Model
Consequence Evaluator
Object Tracker -‐ Localiser
S-‐tuple of safe ac=ons (a3, a4)
N-‐tuple of all possible ac=ons (a1, a2, a3, a4)
Copyright © Alan Winfield 2013
A scenario with safety hazards Consider a robot that has four possible next ac=ons: 1. turn leq 2. move ahead 3. turn right 4. stand s=ll Hole
Robot
Wall
Copyright © Alan Winfield 2013
A scenario with safety hazards Consider a robot that has four possible next ac=ons: 1. turn leq 2. move ahead 3. turn right 4. stand s=ll
Hole
Wall
Robot ac(on
Posi(on change
Robot outcome
Consequence
Ahead leq 5 cm Collision Robot collides with wall
Ahead 10 cm Collision Robot falls into hole
Ahead right 20 cm No-‐collision Robot safe
Stand s=ll 0 cm No-‐collision Robot safe
Copyright © Alan Winfield 2013
Towards an ethical robot
Which robot ac=on would lead to the least harm to the human?
Copyright © Alan Winfield 2013
Towards an ethical robot
Which robot ac=on would lead to the least harm to the human?
Robot ac(on
Robot outcome
Human outcome
Consequence
Ahead leq 0 10 Robot safe; human falls into hole
Ahead 10 10 Both robot and human fall into hole
Ahead right 4 4 Robot collides with human
Stand s=ll 0 10 Robot safe; human falls into hole
Outcome scale 0:10, equivalent to Completely safe: Very dangerous
Copyright © Alan Winfield 2013
Combining safety and ethical rules
IF for all robot actions, the human is equally safe!THEN (* default safe actions *)!!output s-tuple of safe actions!
ELSE (* ethical actions *)! !output s-tuple of actions for least unsafe human
outcomes!
Consider Asimov’s 1st and 3rd laws of robo=cs: (1) A robot may not injure a human being or, through inac=on, allow a human
being to come to harm, (3) A robot must protect its own existence as long as such protec=on does not
conflict with the First (or Second) Laws
Isaac Asimov, I, ROBOT, 1950
Copyright © Alan Winfield 2013
Extending into Adap=vity Sense data
Actuator demands
The loop of generate and test
Robot Controller
Robot Controller
Robot Model
World Model
Consequence Evaluator
Object Tracker -‐ Localiser
Learned/adap=ve behaviours
Copyright © Alan Winfield 2013
Extending into Adap=vity Sense data
Actuator demands
The loop of generate and test
Robot Controller
Robot Controller
Robot Model
World Model
Consequence Evaluator
Object Tracker -‐ Localiser
Learned/adap=ve behaviours
Copyright © Alan Winfield 2013
Challenges and open ques=ons
• Fidelity: to model both the system and its environment with sufficient fidelity;
• To connect the IM with the system’s real sensors and actuators (or equivalent);
• Timing and data flows: to synchronize the internal model with both changing perceptual data, and efferent actuator data;
• Valida5on, i.e. of the consequence rules.
Major challenges: performance
• Example – imagine placing this Webots simula=on inside each NAO robot:
Note the simulated robot’s eye view of it’s world
A science of simula=on: the CoSMoS approach
The Complex Systems Modelling and Simula=on (CoSMoS) process, from Susan Stepney, et al, Engineering Simula=ons as Scien=fic Instruments — a paaern language, Springer, in prepara=on.
The CoSMoS Process Version 0.1: A Process for the Modelling and Simula=on of Complex Systems, Paul S. Andrews, et al, Dept of Computer Science, University of York, Number YCS-‐2010-‐453
Major challenges: =ming
• When and how oqen do we need to ini=ate the generate-‐and-‐test-‐loop (IM cycle)? – Maybe when the object tracker senses a nearby object star=ng to move..?
• How far ahead should the IM simulate – Let us call this =me ts. if ts is too short the IM will not encounter the hazard; too long will slow down the robot.
– Ideally ts and its upper limit should be adap=ve.
How self-‐aware would this robot be?
• The robot would not pass the mirror test – Haikkonen (2007), Reflec=ons of consciousness
• However, I argue this robot would be minimally but sufficiently self-‐aware to merit the label – But this would have to be demonstrated by the robot behaving in interes5ng ways, that were not pre-‐programmed, in response to novel situa5ons
– Valida=ng any claims to self-‐awareness would be very challenging
Some neuroscien=fic plausibility?
• Libet’s famous experimental result showed that ini=a=on of ac=on occurs before the conscious decision to make take that ac=on – Libet, B (1985), Unconscious cerebral Ini=a=ve and the role of
conscious will in voluntary ac=on, Behavioral and Brain Science, 8, 529-‐539.
• Although controversial there appears to be a growing body of opinion toward consciousness as a mechanism for vetoing ac=ons – Libet coined the term: free won’t
In conclusion • I strongly suspect that self-‐awareness via internal models might prove to be the only way to guarantee safety in robots, and by extension autonomous systems, in unknown and unpredictable environments – and just maybe provide ethical behaviours too
Thank you!
Reference for the work of this talk: Winfield AFT, Robots with Internal Models: A Route to Self-‐Aware and Hence Safer Robots, accepted for The Computer AJer Me, eds. Jeremy Pia and Julia Schaumeier, Imperial College Press, 2013.