Transcript
iOCfIFBBpVY • Anca Dragan: Human-Robot Interaction and Reward Engineering | Lex Fridman Podcast #81
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Language: en
the following is a conversation with
ANCA Jorgen a professor of Berkeley
working on human robot interaction
algorithms and looked beyond the robots
function in isolation and generate robot
behavior that accounts for interaction
and coordination with human beings
she also consults at way Moe the
autonomous vehicle company but in this
conversation she's 100% wearing her
Berkeley hat she is one of the most
brilliant and fun roboticists in the
world to talk with I had a tough and
crazy day leading up to this
conversation so I was a bit tired even
more so than usual but almost
immediately as she walked in her energy
passion and excitement for human robot
interaction was contagious so I had a
lot of fun and really enjoy this
conversation this is the artificial
intelligence podcast if you enjoy it
subscribe I need to review it with five
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an organization that is helping to
advanced robotics and STEM education for
young people around the world and now
here's my conversation with Enka Droog
on
when did you first fall in love with
robotics I think it was a very gradual
process and it was somewhat accidental
actually because I first started getting
into programming when I was a kid and
then into Mass and then into compute I
disliked computer science was the thing
I was gonna do and then in college I got
into AI and then I applied to the
robotics Institute at Carnegie Mellon
and I was coming from this little school
and Germany didn't know any nobody had
heard of but I had spent an exchange
semester at Carnegie Mellon so I had
letters from Carnegie Mellon so that was
the only play you know I might he said
no Berkeley said no Stanford said no
that was the only place I got into so I
went there it's a robotics Institute and
I thought that robotics is a really cool
way to actually apply the stuff that I
knew and loved like optimization so
that's how I got into robotics I have a
better story how I got into cars which
is I you know I used to do mostly
manipulation in my PhD but now I do kind
of a bit of everything application wise
including cars and I got into cars
because I was here in Berkeley while I
was a PhD student still for RSS 2014
better be organized in and he arranged
for it was Google at a time to give us
rides and self-driving cars and I was in
a robot and it was just making decision
after decision the right call and he was
so amazing so it was a whole different
experience right it's just I mean
manipulation is so hard you can't do
anything and there was was it the most
magical robot you've ever met so like
for me to mean Google self-driving car
for the first time was like a
transformative moment the guy had two
moments like that that and spot mini I
don't know if you met Bob many for
Boston Dynamics I felt like I felt like
I fell in love or something like it
because I thought I know how a spot many
works right it's just I mean there's
nothing truly special it is it's great
engineering work but the
anthropomorphism that went on into my
brain
they came to life like a head little arm
and like and looked at me he she looked
at me you know I don't know there's a
magical connection there and it made me
realize wow robots can be so much more
than things that manipulate objects they
can be things that have a human
connection
Jeff was a self-driving car the moment
like it was there a robot that truly
sort of inspired you that was I remember
that experience very viscerally riding
in that car and being just wowed I I had
the they gave us a sticker that said I
wrote in a self-driving car and I had
this cute little Firefly on yes and our
logo that was like the smaller were like
you had the really cute one yeah and and
I put it on my laptop and I had that for
years until I finally changed my laptop
out and you know what about if we walk
back you mention optimization at like
what beautiful ideas inspired you in
math computer science early on like why
get into this field seems like a cold
and boring field of math like what was
exciting to you about it the thing is I
liked math from very early on from fifth
grade is when I got into the math
Olympia and all of that are you competed
yeah this it Romania is like our
national sport do you speak I understand
so I got into that fairly early and and
it was little maybe to just theory with
no kind of I didn't kind of how - didn't
really have a goal and I didn't
understanding which was cool I always
liked learning and understanding but
there was no can what am i applying this
understanding to and so I think that's
how I got into more heavily into
computer science cuz it was it was kind
of math meets something you can do
tangibly in the world do you remember
like the first program you've written
okay the first program I've written with
I kind of do it wasn't cute basic and
fourth grade and it was drawing like a
circle right yeah you know I don't know
how to do that anymore
right that's like the first thing that
they taught me I was like you could take
a special
I wouldn't say was an extra isn't a
sense an extracurricular so you could
sign up for you know dance or music or
programming and I did the programming
thing and I was like what what I know
why did you compete in program like
these days Romania probably that's like
a big thing there's a program of
competition hmm what was that did that
touch you at all did a little bit of the
computer science Olympian but not not as
seriously as I did the math Olympiad so
is programming yeah it's basically
here's a hard math problem solve it with
a computer it was kind of yeah it's more
like algorithms exactly it's not where's
algorithmic so okay you kind of
mentioned the Google self-driving car
but outside of that Oh what's like who
or what is your favorite robot real or
fictional that I captivated your
imagination throughout I mean I guess
you kind of alluded to the Google
self-driving the Firefly was a magical
moment but is there something else it
was I think there was the Lexus by the
way this was back back then but yeah so
good question I am okay my favorite
fictional robot is Wally and I love how
amazingly expressive it is some personal
things a little bit about expressive
motion kinds of things you were staying
with you can do this and it's a head and
it's a manipulator and what does it all
mean I like to think about that stuff I
love Pixar
I love animation I love Wally has two
big eyes I think or no yeah it has these
um these cameras and they move so yeah
that's it so you know it goes through
and then it's super cute
it's yeah I think you know the way it
moves it's just so expressive the timing
of that motion what is doing with its
arms and what it's doing with these
lenses is amazing and so I've I've
really liked that from the start and
then on top of that sometimes I shared
this it's a personal story I share with
people or when I teach about AI or
whatnot my husband proposed to me
by building a Wally and he actuated it
so it's seven degrees of freedom
including the lens thing and it kind of
came in and it had the he made it have
like a you know the belly box opening
thing so it just did that and then it's
filled out this box made out of Legos
that open slowly and then BAM no yeah
yeah it was it was quite quite it's at a
bar it could be like the most impressive
thing I've ever heard
okay special connection to Wally long
story short I like Wally because I like
animation and I like robots and I like
you know the fact that this was I we
still have this robot to this day what
how hard is that problem do you think of
the expressivity of robots like the with
the Boston Dynamics I never talked to
those folks about this particular
element I've talked to him a lot but it
seems to be like almost an accidental
side effect for them that they weren't I
don't know if they're faking it they
weren't trying to okay they do say that
the the gripper on it was not intended
to be a face I don't know if that's a
honest statement but I think they're
legitimate and so do we automatically
just anthropomorphizing and youths up
anything we could see about a robot it's
like the the question is how hard is it
to create a wall-e type robot that
connects so deeply with us humans what
do you think it's really hard right so
it depends on what settings so if you
want to do it in this very particular
narrow setting where it does only one
thing and it's expressive then you can
get an animator you know can have fixer
on call come in design some trajectory
is there was a a key had a robot called
Cosmo
where they put in some of these
animations that part is easy right the
hard part is doing it not via these kind
of handcrafted behaviors but doing it
generally autonomously like I want robot
say I don't work on just to clarify I
don't I used to work a lot on this I
don't work on that quite as much these
days but
but have the notion of having robots
that you know when they pick something
up and put it in a place they can do
that with various forms of style or you
can say well this robot is you know
succeeding at this desk and is confident
versus its hesitant versus you know
maybe it's happy or it's you know
disappointed about something some
failure that it had or I think that when
robots move they can communicate so much
about internal states or perceived
internal states that they have and I
think that's really useful in an element
that we'll want in the future because I
was reading this article about how kids
are kids are being rude to Alexa because
they can be rude to it and it doesn't
really get angry right it doesn't reply
it in any way it just says the same
thing so I think there's at least for
that for the for the correct development
of children to learn that these things
and you kind of react differently I also
think you know you walk in your home and
you have a personal robot and if you're
really pissed presumably robot just kind
of behave slightly differently than one
you're super happy and excited but it's
really hard because it's I don't know I
don't you know the way I would think
about it and the way I've thought about
it when it came to in expressing goals
or intent its our intentions for robots
it's well what's really happening is
that instead of doing robotics where you
have your state and you have your action
space and you have your space the reward
functions are trying to optimize now you
kind of have to expand the notion of
state to include this human internal
state what is the person actually
perceiving what do they think about the
robots
something's better and then you have to
optimize in that system and so that
means you have to understand how your
motion your actions end up sort of
influencing the observers kind of
perception of you and it's very it's
very hard to write math about that right
so when you start to think about
incorporating the human into the state
model
apologize for the philosophical question
but how complicated are human beings do
you think like can they be reduced to
two kind of almost like an object that
moves and maybe has some basic intents
or is there something do we have to
model things like mood and general
aggressiveness and time I mean all these
kinds of human qualities or like game
theoretic qualities like what's your
sense how complicated it is how hard is
the problem of human robot interaction
yeah should we talk about what the
problem of human robot is yeah this is
what I mean talk about how that yeah so
and by the way I'm gonna talk about this
very particular view of human robot
interaction right which is not so much
on the social side or on the side of how
do you have a good conversation with the
robot what should the robots appearance
be throws out that if you make robots
taller versus shorter this has an effect
on how people act with them so I'm not
I'm not talking about that but I'm
talking about this very kind of narrow
thing which is you take if you want to
take a task that a robot can do in
isolation in a lab out there in the
world but in isolation and now you're
asking what does it mean for the robot
to be able to do this task for
presumably what it's actually angola's
which is to help some person that ends
up changing the problem in two ways the
first way to changes the problem is that
the robot is no longer the single agent
acting there you have humans who also
take actions in that same space you know
cars navigating around people robots
around an office navigating around the
people in that office if I send the
robot to over there in the cafeteria to
get me a coffee
then there's from other people reaching
for stuff in the same space and so now
you have your robot and you're in charge
of the actions that the robot is taking
then you have these people who are also
making decisions and taking actions in
that same space and even if you know the
robot knows what it's what it should do
and all of that just coexisting with
these people right kind of getting the
since the gel well to mesh well together
that sort of the problem number one and
then there's problem number two which is
goes back to this notion of I if I'm a
programmer I can specify some objective
for the robot to go off and optimize you
can specify the task but if I put the
robot in your home presumably you might
have your own opinions about well okay I
want my house clean but how do I want it
clean then how should robot how close to
me it should come and all of that and so
I think those are the two differences
that you have your acting around people
and you what you should be optimizing
for should satisfy the preferences of
that end user not of your programmer who
programmed you yeah and the Preferences
thing is tricky so figuring out those
preferences be able to interactively
adjust to understand what the human is
so really boys ought to be understand
the humans in order to interact with
them in order to please them right so
why is this hard what yeah why is
understanding humans hard so I think
there's two tasks about understanding
humans that in my mind are very very
similar but not everyone agrees so
there's the task of being able to just
anticipate what people will do we all
know that cards need to do this right we
all know that well if I navigate around
some people the robot has to get some
notion of ok where where is this person
gonna be so that's kind of the
prediction side and then there's what
what you are saying satisfying the
preferences right so adapting to the
person's preference is knowing what to
optimize for which is more this
inference side this what is what does
this person want what is their intent
what are their preferences and to me
those kind of go together because I
think that in if you at very least if
you can understand if you look at human
behavior and understand what it is that
they want then that's sort of the key
enabler to being able to anticipate what
they'll do in the future because I think
that you know we're not arbitrary we
make these decisions that we make we act
in the way we do because we're trying to
achieve
things and so I think that's the
relationship between them now how
complicated do these models need to be
in order to be able to understand what
people want so we've gotten a long way
in robotics with something called
inverse reinforcement learning which is
the notion of someone acts demonstrates
what how they want this thing done what
isn't inverse reinforcement learning you
said it right so it's it's the problem
of take human behavior and infer reward
function from this figure out what it is
that that behavior is optimal with
respect to and it's a great way to think
about learning human preferences in the
sense of you know you have a car and the
person can drive it and then you can say
well okay I can actually learn what the
person is optimizing for I can learn
their driving style or you can you can
have people demonstrate how they want
the house clean and then you can say
okay this is this is I mean I'm getting
the trade-offs that they're that they're
making I'm getting the Preferences that
they want out of this and so we've been
successful in robotics somewhat with
this and it's a it's based on a very
simple model of human behavior which is
remarkably simple which is that human
behavior is optimal with respect to
whatever it is that people want right so
you make that assumption and now you can
kind of inverse through that's why it's
called inverse well really optimal
control but but also inverse
reinforcement learning so this is based
on utility maximization in economics
press back in the forties fine women
mortgage time or like okay people are
making choices by maximizing utility go
and then in the late 50s we had loose
and Shephard come in and say people are
a little bit noisy and approximate in
that process so they might choose
something kind of stochastic lee with
probability proportional to how much
utility something has there's a bit of
noise in there on this has translated
into
buttocks and something that we call
Boltzmann rationality so it's a kind of
an evolution of inversed reinforcement
learning that accounts for four human
noise and we've had some success with
that too for these tasks where it turns
out people act noisily enough that you
can't just do vanilla the vanilla
version ah you can account for noise and
still infer what what they seem to want
based on this man now we're hitting
tasks word that's no not enough and what
are examples where are you damn desk so
imagine you're trying to control some
robot that's that's fairly complicated
trying to control the robot arm cuz
maybe you're a patient with a motor
impairment and you have this wheelchair
mounted army in China to control it
around or one test that we've looked at
with Sergei is and our students did is a
lunar lander so just I don't know if you
know this Atari game it's called lunar
lander it's it's really hard people
really suck at landing the same mostly
they just crash it left and right okay
so this is the kind of toss for imagine
you're trying to provide some assistance
to a person operating such such a robot
where you won the kind of the autonomy
to kick can figure out what it is that
you're trying to do and help you do it
it's really hard to do that for say
lunar lander because people are all over
the place and so they seem much more
noisy than really irrational that's an
example of a task where these models are
kind of failing us and it's not
surprising because so we you know we
talk about a 40s utility late fifties
sort of noisy then the seventies came
and behavioral economics started being a
thing where people are like no no no no
no people are not rational people are
messy and emotional and irrational and
have all sorts of heuristics that might
be domain-specific and they're just
they're just a messy mess so so what do
you so what does my robot do to
understand what you won and it's a very
it's very that's why it's complicated
it's you know for the most part we get
away with pretty simple models until we
don't and then the question is what do
you do then
um and it I had days when I wanted to
you know pack my bags and go home and
jobs because it's just it feels really
daunting to make sense of human behavior
enough that you can reliably understand
what people want especially as you know
robot capabilities will continue to get
developed you'll get these systems that
are more and more capable of all sorts
of things and then you really want to
make sure that you're telling them the
right thing to do what is that thing
well read it in human behavior so if I
just sit here quietly and try to
understand something about you but
listening to you talk it would be harder
than if I got to say something and ask
you and interact and control okay can
you can the robot help its understanding
of the human by inflowing it influencing
the behavior by actually acting yeah
absolutely so one of the things that's
been exciting to me lately is this
notion that when you tried to that that
that when you try to think of the
robotics problem as okay I have a robot
and it needs to optimize for whatever it
is that a person wants it to optimize as
opposed to maybe what a programmer said
that problem we think of as a human
robot collaboration problem in which
both agents get to act in which the
robot knows less than the human because
the human actually has access to and you
know at least implicitly to what it is
that they want they can't write it down
but they can they can talk about it they
can give all sorts of signals they can
demonstrate and and but the robot
doesn't need to sit there and passively
observe human behavior and try to make
sense of it the robot can act too and so
there's these information gathering
actions that the robot can take to sort
of solicit responses that are actually
informative so for instance this is not
for the purpose of assisting people but
with kind of back to coordinating with
people in cars and all of that
one thing that dorsa did was so we were
looking at cars being able to navigate
around people and you might not know
exactly the driving style of a
particular individual that's next to you
but you want to change lanes in front of
them navigating around other humans
inside cars yeah good good clarification
question so you have an autonomous car
and it's trying to navigate the road
around human driven vehicles similar
things ideas applied to pedestrians as
well but let's just take human driven
vehicles so now you're trying to change
a lane well you could be trying to infer
the driving style of this person next to
you you'd like to know if they're in
particular if they're sort of aggressive
or defensive if they're gonna let you
kind of go in or if they're gonna not
and and it's very difficult to just you
know when if you think that if you want
to hedge your bets that maybe they're
actually pretty aggressive I shouldn't
ride this you kind of end up driving
next to them and driving next to them
right and then you you don't know
because you're not actually getting the
observations that you get away someone
drives when they're next to you and they
just need to go straight it's kind of
the same because if they're aggressive
or defensive and so you need to enable
the robot the reason about how it might
actually be able to gather information
by changing the actions that it's taking
and then the robot comes up with these
cool things where it kind of not just
towards you and then sees if you're
gonna slow down or not then if you slow
down it sort of updates its model of you
and says oh okay
you're more on the defensive side so now
I can actually that's a fascinating
dance as so that's so cool
you could use your own actions to gather
information that's uh that feels like
I'm totally open exciting new world of
robotics prop I mean how many people are
even thinking about that kind of thing
because it's it's actually leveraging
human I mean most roboticist I've talked
to a lot of you know colleagues and so
on are kind of being honest kind of
afraid of humans because they're messy
and complicated right I understand
um going back to what we're talking
about earlier right now we're kind of in
this dilemma
okay there are tasks that we can just
assume people are approximately rational
for and we can figure out what they want
we can figure out their goals in fear
are their driving styles whatever cool
they're these tasks that we can't so
what do we do right do we pack our bags
and go home and this one is just I've
had a little bit of hope recently um and
I'm kind of doubting myself scoff what
do I know that you know 50 years of
behavioral economics hasn't figured out
but maybe it's not really in
contradiction with what with the way
that field is headed but basically one
thing that we've been thinking about is
instead of kind of giving up and saying
people are too crazy and irrational for
us to make sense of them maybe we can
give them a bit the benefit of the doubt
and maybe we can think of them as
actually being relatively rational but
just under different assumptions about
the world about how the world works
about you know they don't have we when
we think about rationality and bliss the
assumption is or they're rational under
all the same assumptions and constraints
as the robot right what if this is the
state of the world that's what they know
this is the transition function that's
what they know this is the horizon
that's what they know but maybe maybe
the kind of this difference the way the
reason they can seem a little messy and
hectic especially to robots is that
perhaps they just make different
assumptions or have different beliefs so
I mean that's that's another fascinating
idea that this are kind of anecdotal
desire to say that humans are irrational
perhaps grounded behavioral economics is
is that we just don't understand the
constraints and their awards under which
they operate and so our goal shouldn't
be to throw our hands up and say they're
irrational is to say let's try to
understand what are the constraints what
it is that there must be assuming that
makes this behavior make sense good life
lesson right good life that's true it's
just outside a robot is good too that's
communicating with humans that's just a
good assume that you just don't have
empathy right it's uh this is maybe
there
something you're missing and you know
and it's you know it especially happens
to robots because they're kind of dumb
and they don't know things and
oftentimes people are sort of super
irrational and that they actually know a
lot of things that robots don't
sometimes like with the lunar lander the
robot you know knows much more so it
turns out that if you try to say look
maybe people are operating this thing
but assuming a much more simple fight
physics model because they don't get the
complexity of this kind of craft or the
robot arm with seven degrees of freedom
when these inertia and whatever so so
maybe they have this intuitive physics
model which is not you know this notion
of intuitive physics is something that
good you just studied actually in
cognitive science was like Josh
Tenenbaum Tom Griffiths what kind of
stuff and and what we found is that you
can actually try to figure out what what
physics model kind of best explains
human actions and then you can use that
to sort of correct what it is that
they're commanding the craft to do so
they might you know be sending the craft
somewhere but instead of executing that
action you can sort of take a step back
and say according to their intuitive if
the world worked according their
intuitive physics model where do they
think that the craft is going war day
where are they trying to send it to and
then you can use the real physics right
the universe of that to actually figure
out what you should do so that you do
that instead of where they were actually
sending you in the real world and I kid
you not it word peopled landed there the
damn thing and you know in between the
two flags and and and all that so it's
not conclusive in any way but I'd say
it's evidence that
yeah maybe we're kind of under
estimating humans in some ways when
we're giving up and saying oh there's
just crazy noisy then you then you try
to explicitly try to model the kind of
worldview that they that they have
that's right that's right it's not to I
mean there's things to be here for
Konami's through that that that for
instance I've touched upon the planning
horizon so there's this idea that I just
bounded rationality essentially and the
idea that well maybe we work under
computational constraints and I think
kind of our view recently has been take
the bellmen update
nai and just break it in all sorts of
ways by saying state no no no the person
doesn't get to see the real state maybe
they're estimating somehow transition
function no no no no even the actual
reward evaluation maybe they're still
learning about what it is that they want
like like you know when you watch
netflix and you know you have all the
things and then you have to pick
something imagine that you know the D
the AI system interpreted that choice as
this is the thing you prefer to see and
how are you gonna know you're still
trying to figure out what you like what
you don't like etc so I mean it's
important to also account for that so
it's not irrationality precise doing the
right thing under the things that they
know yeah that's brilliant
you mentioned recommender systems what
kind of and we're talking about human
robot interaction kind of problem spaces
are you thinking about so is it robots
like wheeled robots of autonomous
vehicles is it object manipulation like
when you think about human robot
interaction in your mind and maybe I'm
tree could speak for the entire
community of human robot interaction no
but like what are the problems of
interest here is and does it you know I
kind of think of open domain dialogue as
human robot interaction and that happens
not in the physical space but it could
just happen in in the virtual space so
word who wears the boundaries of this
field for you when you're thinking about
the things we've been talking about yeah
so I I tried to find kind of underlying
I don't know what to even call them I
get try to work on you know I might call
what I do the kind of working on the
foundations of algorithmic human robot
interaction and trying to make
contributions there and and it's
important to me that whatever we do is
actually somewhat domain agnostic when
it comes to is it about you know
autonomous cars or is it about
quadrotors or is it a basis or the same
underlying principles apply of course
when you're trying to get a particular
to work usually have to do some extra
work to adapt that to that particular
domain but these things that we were
talking about around well you know how
do you model humans it turns out that a
lot of systems need to quote benefit
from a better understanding of how human
behavior relates to what people want and
need to predict human behavior physical
robots of all sorts and and beyond that
and so I used to do manipulation I used
to be you know picking up stuff and then
I was picking up stuff with people
around and now it's sort of very broad
when it comes to the application level
but in a sense very focused on ok how
does the problem need to change how do
the algorithms need to change when we're
not doing a robot by itself you know
emptying the dishwasher but we're
stepping outside of that oh I thought
that popped into my head just now on the
game theoretic side I think you said
this really interesting idea of using
actions to gain more information but if
we think a sort of game theory the
humans that are interacting with you
with you the robot identity of the robot
yeah is they also have a world model of
you mm-hmm
and you can manipulate that and if we
look at autonomous vehicles people have
a certain viewpoint you said with the
kids
people see Alexa as a in a certain way
is there some value in trying to also
optimize how people see you as a robot
is that it or is that a little too far
and away from the specifics of what we
can solve right now so both right so
it's really interesting and we've seen a
little bit of progress on this problem
on pieces of this problem so you can
again it kind of comes down to how
complicated is the human model need to
be but in one piece of work that we were
looking at we just said ok there's these
in there's this
that are internal to the robot and their
what their what the robot is about to do
or maybe what objective what driving
style the robot has or something like
that and what we're gonna do is we're
going to set up a system where part of
the state is the person's belief over
those parameters and now when the robot
acts that the person gets new evidence
about this robot internal state and so
they're updating their mental model of
the robot right so if they see a card
that sort of cut someone off Tory god
that's an aggressive card they no more
right if they see sort of a robot head
towards a particular door they're like
are the robots trying to get to that
door so this thing that we have to do
with humans to try to understand their
goals and intentions humans are
inevitably gonna do that to robots and
then that raises this interesting
question that you asked which is can we
do something about that this is gonna
happen inevitably but we can sort of be
more confusing or less confusing to
people and it turns out you can optimize
for being more informative and less
confusing if you if you have an
understanding of how your actions are
being interpreted by the human how
they're using these actions to update
their belief and honesty all we did is
just Bayes rule basically okay first has
a belief they see an action they make
some assumptions about how the robot
generates its actions presumably is
being rational because robots are
rational see reasonable to assume that
about them and then they incorporate
that that new piece of evidence the
Bayesian sense and their belief and they
obtain a posterior and now the robot is
trying to figure out what actions to
take such that it steers the person's
belief to put as much probability mass
as possible on the correct on the
correct parameters so that's kind of a
mathematical formalization of that but
my worry and I don't know if you want to
go there with me but I about this quite
a bit um the the kids talking to alexa
disrespectfully worries me i worry in
general about human nature I guess I
grew up in Soviet Union World War two
I'm gonna do two so with the Holocaust
and everything I just worry about how we
sometimes treat the other the the group
that we call out or whatever it is
through human history the group that's
the other has been changed faces but it
seems like the robot will be the other
the other the the next the other and one
thing is it feels to me that robots
don't get no respect they get shoved
around shoved around in is there one at
the shallow level for a better
experience it seems that robots need to
talk back a little bit like into my
intuition says I mean most companies
from sort of Roomba autonomous vehicle
companies might not be so happy with the
idea that a robot has a little bit of an
attitude but I feel it feels to me that
that's necessary to create a compelling
experience like we humans don't seem to
respect anything that doesn't give us
some attitude that or like Miss mix of
mystery and attitude and anger and did
that threatens us subtly maybe
passive-aggressively I don't it seems
like we humans yet need that dude what
are you is there something you have
thoughts on this one is one is it it's
we respond to you know someone being
assertive but we also respond to someone
being vulnerable so I think robots but
my first thought is that robots get
shoved around and and bullied a lot
because they're sort of you know
tempting and they're so showing off or
they appear to be showing off and so I
think current going back to these things
we were talking about in the beginning
of making robots a little more a little
more expressive a little bit more like
oh that wasn't cool to do and now I'm
bummed right I think that that can
actually help because people can't help
but anthropomorphize and respond to that
even that though the emotion being
communicate is not in any way a real
thing and people know that it's not a
real T because they know it's just a
machine
we're still interpret you know we can
work with we watch there's this a famous
psychology experiment with little
triangles and kind of dots on a screen
and a triangle is chasing the square and
get
angry at the darn triangle because why
is it not leaving the square alone so
that's yeah we can't helps that was the
first thought the vulnerability is
really interesting that I I think of
like being pushing back being assertive
as the only mechanism of getting of
forming a connection of gaining respect
but perhaps vulnerability perhaps
there's other mechanisms that are less
threatening yeah a little bit yes but
then this this other thing that we can
think about is it goes back to what you
were saying that interaction is really
game theoretic all right so the moment
you're taking actions in the space
humans are taking actions in that same
space but you have your own objective
which is you know you're a car you need
to get your passenger to the destination
and then the human nearby has their own
objective which someone overlaps with
you but not entirely you boat you're not
interested in getting into an accident
with each other but you have different
destinations and you want to get home
faster and they want to get home faster
and that's a general of some game at
that point and so that's I think that's
what it's reading it as such is kind of
a way we can step outside of this kind
of mode that where you try to anticipate
what people do and you don't realize you
have any influence over it while still
protecting yourself because your
understanding that people also
understand that they can influence you
and it's just kind of back and forth is
this negotiation which is really really
talking about different equilibria of a
game the very basic way to solve
coordination is to just make predictions
about what people will do and then stay
out of their way and that's hard for the
reasons we talked about which is how you
have to understand people's intentions
implicitly explicitly who knows but
somehow you have to get enough of an
understanding of that we all anticipate
what happens next and so that's
challenging but then it's further
challenged by the fact that people
change what they're do based on what you
do because they don't they don't plan in
isolation either right so when you see
cars trying to merge on a highway
and not succeeding one of the reasons
this can be is because you you they they
look at traffic that keeps coming they
predict what these people are planning
on doing which is to just keep going and
then they stay out of the way because
there's not there's no feasible plan
right any planning would actually
intersect with one of these other people
so that's bad so you get stuck there
so now kind of if if you start thinking
about it as no no no actually these
people change what they do depending on
what the car does like if the car
actually tries to kind of inch itself
forward they might actually slow down
and let the car in and down take an
advantage of that well that you know
that's kind of the next level we call
this like this under actuated system
idea where it's gonna under actresses
and robotics but it's kind of it's you
don't your influence these other degrees
of freedom but you don't get to decide
what somewhere it's seen you mention it
this the the human element in this
picture as under actuate it said you
know you understand under actuator about
robotics is you know that you can't
fully control the system so you can't go
in arbitrary directions in the
configuration space under your control
yeah it's a very simple way of under
actuation where basically there's
literally these degrees of freedom that
you can control and these are affirmed
that you can't but you influence them
and I think that's the important part is
that they don't do whatever regardless
of what you do that what you do
influence is what they end up doing I
just also like the the poetry of calling
human robot interaction and under
actuated robotics problem and y'all so
much sort of nudging it seems that there
and I don't know I think about this a
lot in the case of pedestrians I've
collected hundreds of hours of videos I
like to just watch pedestrians mmm-hmm
and it seems that it's a funny hobby
yeah it's weird because I learn a lot I
learned a lot about myself about our
human human behavior from watching
pedestrians watching people in their
environment basically crossing the
street is
you're putting your life on the line you
know I don't know tens of millions of
time in America every day is people are
just like playing this weird game of
chicken when they cross the street
especially when there's some ambiguity
about the right-of-way that has to do
either with the rules of the road or
with the general personality of the
intersection based on the time of day
and so on I mean and this nudging idea I
don't you know it seems that people
don't even nudge they just aggressively
take make a decision somebody there's a
runner that gave me this advice I
sometimes run in in the street and you
know not in this jannah sidewalk and you
said that if you don't make eye contact
with people when you're running they
will all move out of your way it's
called civil and attention civil
inattention that's the thing oh wow I
need to look this stuff but it works
what is that my sense was if you
communicate like confidence in your
actions that you're unlikely to deviate
from the action that you're following
that's a really powerful signal to
others that they need to plan around
your actions as opposed to nudging where
you're sort of hesitantly then the
hesitation might communicate that you're
now you're still in the dance in the
game that they can influence with their
own actions I've recently had
conversation with Jim Keller who is a
sort of this legendary chip or chip
architect but he also let the autopilot
in for a while and his intuition that
driving is fundamentally still like a
ballistics problem like you can ignore
the human element that it's just not
hitting things and you can kind of learn
the right dynamics required to do the
merger and all those kinds of things and
then my sense is and I don't know if I
can provide a definitive proof of this
but my sense is I can order a magnitude
or more more difficult when humans are
involved like it's not simply a object a
collision avoidance problem which where
does your intuition of course nobody
knows the right answer here but
where does your intuition fall on the
difficulty fundamental difficulty of the
driving problem when humans are involved
yeah good question I have many opinions
on this
imagine downtown San Francisco yeah yeah
it's crazy busy everything okay now take
all the humans out no pedestrians no
human driven vehicles no cyclists no
people and little skill electric
scooters have been around nothing I
think we're done I think driving at that
point is done we're done I did nothing
really that's nice tilt needs to be
solved about that well let's pause there
i I think I agree with you that guy and
I think a lot of people here will agree
with that but we need to sort of
internalize that idea so what's the
problem there because we're not quite
yet be done with that because a lot of
people kind of focus on the perception
problem well a lot of people kind of map
autonomous driving into how close are we
to solving being able to detect all the
you know the the drivable area the
objects in the scene do you see that as
a how hard is that problem so your
intuition there behind your statement
was we might have not solved the yet but
were close to solving basically the
perceptual problem I think the
perception problem I mean and by the way
a bunch of years ago this would not have
been true and a lot of issues and the
space can't we're coming from the fact
that we don't really you know we don't
know what's what's where but I think
it's fairly safe to say that at this
point although you could always improve
on things and all of that you can drive
through downtown San Francisco if there
are no people around there's no really
perception issue standing in your way
there any perception is hard but yeah
it's we've made a lot of progress on the
perceptions on how to undermine the
difficulty of the problem I think
everything about robotics is really
difficult of course you know the the
planning problem the control problem all
very difficult but I think what's what
makes it really you know yeah it might
be I mean you know
and I picked downtown San Francisco I
ate adapting to well now it's snowing
now is no longer snowing now it's
slippery in this way now so the dynamics
part could good I could imagine being
being still somewhat challenging but no
the thing that I think worries us and
our tuition is not good there is the
perceptual problem at the edge cases
sort of stout sauce and Francisco the
nice thing it's not actually it may not
be a good example because cuz you know
what - what you're getting for all
there's like because crazy construction
zones and all yeah but the thing is
you're travelling at slow speeds so it
doesn't feel dangerous to me what feels
dangerous is highway speeds when
everything is to us humans super clear
yeah I'm assuming light are here by the
way I think it's kind of irresponsible
to not use lighter that's just my
personal opinion
depending on your use case but I think
like you know if you if you have the
opportunity to use light are good your
injury makes more sense now so you don't
think vision I really just don't know
enough to say well vision alone what you
know what's like I there's a lot of how
many cameras do you have there's all
sorts of details I imagine their stuff
is really hard to actually see how do
you deal with would glare exactly what
you're saying stuff that people would
see that that that you don't I I think I
have more my intuition comes from
systems that can actually use lighter as
well yeah until we know for sure it's
make sense to be using lidar that's kind
of the safety focus but then deserve the
I also sympathize with the Elon Musk the
statement of lidar as a crutch it's it's
it's uh it's a fun notion to think that
the things that work today is a crutch
for the invention of the things that
will work tomorrow right they get it's
kind of true in the sense that if we you
know that we want to stick to the
conference and you see this in academic
and
settings all the time the things that
work force you to not explore outside
think outside the box I mean that
happened all of that the problem is in
safety critical systems you kind of want
to stick with a thing Sutekh work so
it's a it's an interesting and difficult
trade-off in the in the in the case of
real-world sort of safety critical
robotic systems but so your intuition is
just to clarify yes how I mean how hard
is this human element forger like how
hard is driving when this human element
is involved are we years decades away
from solving it but perhaps actually the
years and the the thing I'm asking it
doesn't matter what the timeline is but
do you think we're how many
breakthroughs away away from its in
solving the human robot interaction
problem to get this to get this right I
think it in a sense it really depends I
think that you know we were talking
about how well look it's really hard
because I'm just know people do is hard
and on top of that playing the game is
hard but I think we sort of have the
fundamental some of the fundamental
understanding for that and then you
already see that these systems are being
deployed in the real world you know even
even driverless because I think now a
few companies that don't have a driver
in the car yeah small areas he's got a
chance to I went to Phoenix and I and I
shot a video with lame-o and you need to
get that video out people didn't give me
slack but this incredible engineering
work being done there and it's one of
those other seminal moments for me in my
life to be able to it sounds silly but
to be able to drive without a with a
ride sorry without a driver in the seat
I mean I was an incredible robotics I
was driven by a robot and without being
able to take over without being able to
take the steering wheel that's a magical
that's a magical moment so in that
regard and those domains at least for
like way mo they're there they're
solving that human there's I mean there
were they're going fattening it felt
fast because you're like freaking out at
first I was this is my first experience
but it's going like the speed limit
right 30 40 whatever it is and there's
humans and it deals with them quite well
I detects them and a good negotiation
the intersections the left turns and all
that so at least in those domains it's
solving them the open question for me is
like how quickly can we expand you know
that's the you know outside of the
weather conditions all those kinds of
things how quickly can we expand to like
cities like San Francisco yeah and I
wouldn't say that it's just you know now
it's just pure engineering and it's
probably the I mean I know by the way
I'm speaking kind of very generally here
as hypothesizing but I I think that that
there are successes and yet no one is
everywhere out there so that seems to
suggest that things can be expanded and
can be scaled and we know how to do a
lot of things but they're still probably
you know new algorithms or modified
algorithms that that you still need to
put in there as you as you learn more
and more about new challenges that get
you get faced when how much is this
problem do you think can be learned
through in turn this is the success of
machine learning and reinforcement
learning how much of it can be learned
from sort of data from scratch and how
much which most of the success of
autonomous vehicle systems have a lot of
heuristics and rule based stuff on top
like human expertise in in injected
forced into the system to make it work
hmm what's your what's your sense how
much
what's the will be the role of learning
in the near term I think I I think on
the one hand that learning is inevitable
here right I think on the other hand and
when people characterize the problem as
it's a bunch of rules that some people
wrote
versus it's an end-to-end RL system or
imitation learning then maybe there's
kind of something missing from maybe
that's that's more so for instance I
think a very very useful tool in this
sort of problem both in how to generate
the cars behavior and robots in general
and how to model human beings is
actually planning search optimization
right so robotics is a Disick Winchell
decision-making problem and when when a
robot can figure out on its own how to
achieve its goal without hitting stuff
and all that stuff you're right all the
good stuff promotion planning 101 I
think of that as very much AI not this
is some rule or something there's
nothing rule-based a bit on that right
it's just you're you're searching
through a space and figure now are you
optimizing through a space and figure
out what seems to be the right thing to
do and I think it's hard to just do that
because you need to learn models of the
world and I think it's hard to just do
the learning part where you don't you
know you don't bother with any of that
because then you're saying well I could
do imitation but then when I go off
distribution I'm really screwed or you
can say I can do reinforcement learning
which adds a lot of robustness but then
you have to do either reinforce my
learning in the real world which sounds
a little challenging or that trial and
error you know or you have to do
reinforce millennion simulation and then
that means well guess why do you need to
model things at least to a to model
people model the world enough that you
you know whatever policy you get of that
is like actually fine to roll out in the
world and do some additional learning
there so do you think simulation by the
way just the the the quick tangent has a
role in the human robot interaction
space like is it useful seems like
humans everything we've been talking
about are difficult to model and
simulate do you think simulation has a
role in this space I do I think so
because
you can take models and train with them
ahead of time for instance you can but
the model sorry to interrupt the models
are sort of human constructed or learned
I think they have to be a combination
because if you get some human data and
then you say this is hog this is gonna
be my model of per the person what are
for simulation and training or for just
deployment time and that's what I'm
planning with as my model of how people
work regardless if you take some data um
and you don't assume anything else and
you just say okay this is this is some
data that I've collected let me fit a
policy to help people work based on that
what does to happen is you collected
some data in some distribution and then
now you're your robot it computes a best
response to that right is sort what
should I do if this is how people work
and easily goes off of distribution
where that model that you've built of
the human completely sucks because out
of distribution you have no idea right
there's if you think of all the possible
policies and then you take only the ones
that are consistent with the human data
that you've observed that still needs a
lot of put a lot of things could happen
outside of that distribution where
you're confident then you know what's
going on by the way this should you have
gotten used to this terminology out of a
distribution within the system machine
learning terminology because it kind of
assumes so distribution is referring to
the the data that you States that you
encounter they've noticed so far at
training time yeah but it kind of also
implies that there's a nice like
statistical model that represents that
data so odd a distribution feels like I
don't know it it uh it raises to me
falafel questions of how we humans
reason out of distribution reasonable
things that are completely we haven't
seen before and so and what we're
talking about here is how do we reason
about what other people do in
you know situations where we haven't
seen them and somehow we just magically
navigate that right you know I can
anticipate what will happen in
situations that are even novel in many
ways and I have a pretty good intuition
for I always get it right but you know
and I might be a little uncertain and so
on I think it's it's this that if you
just rely on data you know you you just
too many possibilities or too many
policies out there that fit the data and
by the way it's not just state it's
clearly kind of history of stake has to
really be able to anticipate what the
person will do it kind of depends on
what they've been doing so far cuz
that's the information you need to kind
of at least implicitly sort of say oh
this is the kind of person that this is
this probably what they're trying to do
so anyway it's like you're trying to map
history States so actually there's many
mapping and history meaning like the
last yes word the last few minutes or
the last few months who knows who knows
how much you need right in terms of your
state is really like the positions of
everything or whatnot and velocities who
knows how much you need and then and
then there's this there's so many
mappings and so now you're talking about
how do you regularize that space what
priors do you impose or what's the
inductive bias so you know there's all
very related things to think about it on
basically water assumptions that we
should be making such that these models
actually generalize outside of the data
that we've seen and now you're talking
about well I don't know what can you
assume maybe you can assume that people
like actually have intentions and that's
what drives their actions maybe that's
you know the right thing to do when you
haven't seen data very nearby that tells
you otherwise I don't know it's a very
open question do you think so that one
of the dreams of artificial intelligence
was to solve common sense reasoning
whatever the heck that means do you
think something like common sense
reasoning has to be solved in part to be
able to solve this dance of human
interaction the driving space or human
robot interaction in general you have to
be able to reason about these kinds of
common-sense concepts of physics of
you know all the things we've been
talking about humans I don't even know
how to express them with words but the
bay the basics of human behavior a fear
of death so like to me it's really
important to encode in some kind of
sense maybe not maybe it's implicit but
it feels that it's important to
explicitly encode the fear of death
that people don't want to die because it
seems silly but like that that the game
of chicken that involves with the
pedestrian crossing the street is
playing with the idea of mortality like
we really don't want to dies that's just
like a negative reward I don't know I it
just feels like all these human concepts
have to be encoded did you share that
sense or is just a lot simpler that I'm
making out to be I think it might be
simpler and I'm the first thing who
likes to complicate is I think where we
simpler than that um because it turns
out for instance if you if you say model
people in the very I don't call it
traditional why I don't know if it's
fair to look at it as a traditional way
but but you know calling people as okay
they're irrational somehow the
utilitarian perspective well in that
once you say that they you automatically
capture that they have an incentive to
keep on being you know Stuart um likes
to stay you can't fetch the coffee if
you're dead Russell that's a good night
so when when you're sort of cheating
agents as having these objectives these
incentives humans or artificial you're
kind of implicitly modeling that they'd
like to stick around so that they can
accomplish those goals um so I think I
think in a sense maybe that's what draws
me so much to the rationality framework
even though it's so broken we've been
able to it's been such a useful
perspective and like we were talking
about earlier what's the alternative I
give up and go home or you know I just
use complete black boxes but then I
don't know
what to assume out of distribution that
come back to this um it's just it's been
a very fruitful way to think about the
problem and a very more positive way
right these people aren't just crazy
maybe they make more sense than we think
but um but I think we also have to
somehow be ready for it to be to be
wrong be able to detect when these
assumptions aren't holding be all of
that stuff let me ask sort of an another
small side of this that we've been
talking about the pure autonomous
driving problem but there's also
relatively successful systems already
deployed out there in what you may call
like level two autonomy or semi
autonomous vehicles whether that's test
autopilot of work quite a bit with
Cadillac super guru system which has a
driver facing camera that detects your
state there's a bunch of basically Lane
centering systems what's your sense
about this kind of way of dealing with
the human robot interaction problem by
having a really dumb robot and and
relying on the human to help the robot
out to keep them both alive is that is
that from the research perspective how
difficult is that problem and from a
practical deployment perspective is that
a fruitful way to approach this human
robot interaction problem I think what
we have to be careful about there is to
not me it seems like some of these
systems not all are making this
underlying assumption that if so I'm a
driver and I'm now really not driving
but supervising and my job is to
intervene right and so we have to be
careful with this assumption that when
I'm if I'm supervising I will be just as
safe as when I'm driving like that I
will you know if I if I wouldn't get
into some kind of accident if I'm
driving I will be able to avoid that
axis
and when I'm supervising to and I think
I'm concerned about this assumption from
a few perspectives so from a technical
perspective it's that when you'll add
something kind of take control and do
its thing and it depends on what that
thing is obviously and how much is
taking on how what things are you
trusting it to do but if you let it do
its thing and take control it will go to
what we might call off policy from the
person's perspective States so stays to
the person wouldn't actually find
themselves in if they were the ones
driving and the assumption that the
person functions just as well there as
they function in the states that they
would normally encounter is a little
questionable now another part is the
kind of the human factor side of this
which is that I don't know about you but
I think I definitely feel like I'm
experiencing things very differently
when I'm actively engaged in the task
versus when I'm a passive observer even
if I try to stay engaged right it's very
different than when I'm actually
actively making decisions and you see
this in life in general like you see
students who are actively trying to come
up with the answer
learn this thing better than when
they're passively told the answer I
think that's some more related and I
think people have studied this in human
factors for airplanes and I think it's
actually fairly established that these
two are not the same so I and that point
because I've gotten a huge amount of
heat on this and I stand by it okay
because I know the human factors
community well and the work here is
really strong and there's many decades
of work show exactly what you're saying
nevertheless I've been continuously
surprised that much of the predictions
of that work has been wrong and what
I've seen so what we have to do I still
agree with everything you said but we
have to be a little bit more open-minded
so the the I'll tell you there's a few
surprising things that super villi kever
ething you said to the word is actually
exactly correct but it doesn't say what
you didn't say is that these systems are
you said you can't assume a bunch of
things but we don't know if he says
are fundamentally unsafe that's still
unknown if there's there's a lot of
interesting things like I'm surprised by
the fact not the fact that what seems to
be anecdotally from well from large data
collection that we've done but also from
just talking to a lot of people when in
the supervisory role of semi autonomous
systems that are sufficiently dumb at
least which is that might be a key
element is the systems not to be dumb
the people are actually more energized
as observer so they're actually better
they're they're better at observing the
situation so there might be cases in
systems if you get the interaction right
or you as a supervisor will do a better
job with the system together I agree I
think that is actually really possible
I guess mainly I'm pointing out that if
you do it naively you're implicitly
assuming something that assumption might
actually really be wrong but I do think
that if you explicitly think about what
the agent reducers that the person still
stays engaged what the so that you
essentially empower the person do more
than they could that's the really the
goal right is you still have a driver so
you want to empower them to be so much
better than they would be by themselves
and that's different it's a very
different mindset then I want them to
basically not join but be ready to sort
of take over so one of the interesting
things we'll be talking about is the
rewards that they seem to be fundamental
to the way robots behaves so broadly
speaking we've been talking about
utility function saw but you comment on
how do we approach the design of reward
functions like how do we come up with
good reward function
[Laughter]
this is you know I used to think I think
about how well it's actually really hard
to specify rewards for interaction
because and it's really supposed to be
what the people want and then you really
you know we talked about how you have to
customize what you want to do to the end
user but I kind of realized that even if
you take the interactive component away
it's still really hard to design reward
functions so what do I mean by that I
mean if we assumed this survey I
paradigm in which there's an agent and
his job is to optimize some objectives
some reward utility lost whatever cost
if you write it out maybe it's a sad
depending on situation or whatever it is
if you write it out and then you deploy
the agent you'd want to make sure that
whatever you specified incentivizes the
behavior you want from the agent in any
situation that the agent will be faced
with right so I do motion planning on my
robot arm I specify some cost function
like you know this is how far away
should try to stay so much amount of
stay away from people and it so much it
matters to be able to be efficient and
blah blah blah Ryan I need to make sure
that whatever I specified those
constraints or trade-offs or whatever
they are that when the robot goes and
solves that problem in every new
situation that behavior is the behavior
that I want to see and what I've been
finding is that we have no idea how to
do that but basically what I can do is I
can sample I can think of some
situations that I think are
representative of what the robot will
face and I can turn and add and tune
some reward function until the optimal
behavior is what I want on those
situations which first of all is super
frustrating because you know through the
miracle of AI we've taken we don't have
to specify rules for behavior anymore
right the
saying before the robot comes up with
the right thing to do you plug in this
situation it optimizes writing that
situation it optimizes but you have to
spend still a lot of time and actually
defining what it is that that criterion
should be make sure you didn't forget
about 50 bazillion things that are
important and how they all should be
combining together to tell the robot
what's good and when it's bad and how
good and how bad and so I think this is
this is a lesson that I don't know kind
of I guess I close my eyes to it for a
while cuz I've been you know tuning cost
functions for 10 years now but it it's
it really strikes me that yeah we've
moved the tuning and like designing of
features or whatever from the behavior
side into the reward side and yes I
agree that there's way less of it but it
still seems really hard to anticipate
any possible situation and make sure you
specify a reward function that when
optimized will work well in every
possible situation so so you're kind of
referring to unintended consequences or
just in general any kind of suboptimal
behavior that emerges outside of the
things you said about out of
distribution suboptimal behavior that is
you know actually optimal I mean this I
guess the idea of unintended consequence
you know it's I've don't respect what
you specified but it's not what you want
and there's a difference between those
but that's not fundamentally a robotics
problem it is a human problem so like
that's the thing yeah right so there is
this thing called good hearts law which
is you start a metric for an
organization and the moment it becomes
on target that people actually optimize
for it's no longer a good metric well
what's it called the good hearts law
good hearts Allah so the moment you
specify a metric it stops doing his job
yeah it stops doing his job um so
there's yeah there's such a thing as off
or optimizing for sayings and and you
know failing to to think ahead of time
of all the possible things that might be
important and so that's
so that's interesting because you story
I work a lot on every word learning from
the perspective of customizing to the
end user but it really seems like it's
not just the interaction with the end
user that's a problem of the human and
the robot collaborating so that the
robot can do what the human one's right
that's kind of back and forward the
robot probing the person being
informative all of that stuff might be
actually just as applicable to this kind
of maybe new form of human robot
interaction which is the interaction
between the robot and the expert
programmer a roboticist designer in
charge of actually specifying what the
hectic wants should do a task for this
professor that's so cool like
collaborating on the reward right
collaborating on the reward design and
so what what does it mean right what is
it when we think about the problem not
as someone specifies all of your job is
to optimize and we start thinking about
your in this interaction and this
collaboration and the first thing that
comes up is when the person specifies a
reward it's not you know gossip was not
like the letter of the law it's not the
definition of the reward function you
should be optimizing because they're
doing their best but they're not some
magic perfect Oracle and the sooner we
start understanding that I think the
sooner we'll get tomorrow but instead of
robots that function better in different
situations and then then you have kind
of say okay well it's it's almost like
the robots are over learning over you're
putting too much weight on the reward
specified by definition and maybe
leaving a lot of other information on
the table like what are other things we
could do to actually communicate to the
robot about what we want them to do
besides attempting to specify a reward
phone yeah you have this awesome and
again it looks the poetry of leaked
information you mentioned
humans leaked information about what
they want you know leaked reward signal
for the for the robot so how do we
detect these leaks yeah what are these
leaks are they just I don't know
that those words recently saw it read it
I don't know where from you and that's
gonna stick with you for a while for
some reason because it's not explicitly
expressed it kind of leaks in directly
from our behavior we do yeah absolutely
so I think maybe something surprising
bits right so we were talking to before
about our my robot arm it needs to move
around people carry stuff put stuff away
all of that and now imagine that you
know the robot has some initial
objective that the programmer gave it so
they can do all these things functional
it's capable of doing that and now I
noticed that it's doing something and
maybe it's coming too close to me
alright and maybe I'm the designer maybe
I'm the end-user and this robot is now
in my home and I push it away so I push
away cuz you know it's a it's a reaction
to what the robot is currently doing and
this is what we call physical human
robot interaction and now there's a lot
of there's a lot of interesting work on
how do you respond to physical human
robot interaction why should the robot
do if such an event occurs and there's
sort of different schools of thought
it's well you know you can sort of treat
it to control theoretical and say this
is a disturbance that you must reject
you can sort of treat it more a kind of
heuristic Leon sorry I'm gonna go into
some like gravity compensation mode so
that means very maneuverable around I'm
gonna go in the direction that the
person push me and and to us part of
realization has been that that is signal
that communicates about the reward
because if my robot was moving in an
optimal way and I intervened that means
that I disagree which is notion of
optimality whatever he thinks is optimal
is not actually optimal and sort of
optimization problems aside that means
that the cost versus reward function is
is incorrect or at least is not what I
wanted to be how difficult a signal to
to inter to make actionable so like I it
cuz this connects to our Thomas vehicle
discussion what they're in the semi
autonomous vehicle or autonomous V
go on a safety driver disengages the car
like they could have disengaged it for a
million reasons yeah yeah so that's true
again it comes back to Kenya can you
structure a little bit of your
assumptions about how human behavior
relates to what they want and you you
know you can't one thing that we've done
is literally just treated this external
torque that they applied as you know
when you take that and you add it with
what the torque the robot was already
applying that overall action is probably
relatively optimal respect to whatever
it is that the person wants and then
that gives you information about what it
is that they want so you can learn that
people want you to stay further away
from them now you're right that there
might be many things that explain just
at one signal that you might need much
more data than that for the person be
able to shape your reward function over
time you can also do this info gathering
stuff that we were talking about now now
we've done that in that context just to
clarify but it's definitely somebody
thought about where you can have the
robot start acting in a way like if
there's a bunch of different
explanations right it moves in a way
where it sees if you corrected in some
other way or not and then kind of
actually plans its motion so that it can
disambiguate then collect information
about what you want anyway so that's one
way that's cut a sort of leaked
information maybe even more subtle
leaked information is if I just press
the e stop right I just I'm doing it out
of panic because the robot is about to
do something bad there's again
information there right okay the robot
should definitely stop but it should
also figure out that whatever was about
to do was not good and in fact it was so
not good then stopping and remaining
stop for a while was better a better
trajectory for it than whatever it is
that it was about to do and that again
is information about what are my
preference is what do I want
speaking of East ops what are your
expert opinions on the Three Laws of
Robotics um Isaac Asimov don't harm
humans obey orders protect yourself I
mean it's a it's a such a silly notion
but I speak to so many people these days
just regular folks just I don't know my
my parents and so on about robotics and
they kind of operate in that space of
you know imagining our future with
robots and thinking what are the ethical
how do we get that dance right I know
the three laws might be a silly notion
but do you do you think about like what
Universal reward functions that might be
that we should enforce on the robots of
the future or is that a little too far
out and it doesn't or is the mechanism
that you just described you shouldn't be
three laws it should be constantly
adjusting kind of thing I think it
should constantly be adjusting I think
that you know the issue with the laws is
I don't even you know they're words and
I have to write math right and have to
translate them into math what does it
mean to us harm me what right because we
just talked about how you try to say
what you want but you don't always get
it right and you want these machines to
do what you want not necessarily exactly
what your literacy you want them you
don't want them to take you literally
you want to take what you're saying and
interpret it in context and that's what
we do with the specified rewards we
don't take them literally anymore from
the designer we not we as a community we
as you know some members are like we and
in some of our collaborators like Peter
bol and Stuart Russell we sort of say
okay the designer specified this thing
but I'm gonna interpret it not as this
is universal reward function that I
shall always optimize always and forever
but as this is good evidence about what
the person wants and I should interpret
that evidence in the context of these
situations that it was specified for
because ultimately that's what the
designers thought about that's what they
had in mind and really them specifying a
reward function that works for me in all
these situations is really kind of
telling me that whatever behavior that
incentivizes must be good behavior
respect to the thing that I should
actually be optimizing for and so
now the robot kinda has uncertainty
about what it is that it should be what
its reward function is and then there's
all these additional signals we've been
finding that it can kind of continually
learn from and adapt its understanding
of what people want every time the
person corrected
maybe they demonstrate maybe they
stopped hopefully not right one really
really crazy one is the environment
itself like our world you don't it's not
you know you observe our world and and
the state of it and it's not that you're
seeing behavior and you're saying how
people are making decisions that are
rational bla bla bla it's but but but
our world is something that we've been
acting when according to our preferences
so I have this example where like the
robot walks into my home and my shoes
are laid down on the floor kind of in a
line right it took effort to do that
even though the robot doesn't see me
doing this you know actually aligning
the shoes it should still be able to
figure out that I want the shoes online
because there's no way for them to have
magically instantiated themselves in
that way someone must have actually just
a good time to do that so it must be
important so the environment actually
tells the varlets information at least
information I mean the environment is
the way it is because humans some are
manipulated is so you have to kind of
reverse engineer the narrative that
happened to create the environments it
is and that leaks the yeah yeah yeah
mission yeah you have to be careful yeah
right because because people don't have
the bandwidth to do everything so just
because you know my house is messy
doesn't mean that I want it to be messy
right but that just shouldn't decide you
know I didn't put the effort into that I
put the effort into something else so
the robot should figure out well that's
something else was more important but it
doesn't mean that you know the house
being messy is not so it's a little
subtle but yeah we really think of it
the state itself is kind of like a
choice that people implicitly made on
how they want their world what book or
books technical fiction or philosophical
had when you like look back your life
had a big impact maybe it was a turning
point was inspiring
maybe we're talking about some silly
book that nobody in their right mind
would want to read or maybe it's a book
that you would recommend to others to
read or maybe those could be two
different recommendations that of books
that could be useful for people on their
journey when I was in it's kind of a
personal story when I was in 12th grade
I got my hands on a PDF copy in Romania
of Russell Norvig a I modern approach I
didn't know anything about AI at that
point I was you know I had watched the
movie The Matrix and and so I started
going through this thing and you know
you were asking in the beginning what
are what are you and just it's it you
know it's math and it's algorithms
what's interesting it was so captivating
this notion that you could just have a
goal and figure out your way through a
kind of a messy complicated situation
so what sequence of decisions you should
make art autonomously to achieve that
goal that was so cool I'm you know I'm
biased but that's a cool book yeah you
can convert you know the goal the goal
of and tell it the process of
intelligence and mechanize it I had the
same experience I was really interested
in psychiatry and trying to understand
human behavior and then AI a modern
approach is like wait you can just
reduce it all yeah so that's and I think
that's stuck with me cuz you know a lot
of what I do
a lot of what we do in my lab is write
math about human behavior combine it
with data and learning put it all
together give it to robots to plan wit
and you know hope that instead of
writing rules for the robots writing
heuristics designing behavior they can
actually autonomously come up with the
right thing to do around people that's
kind of our you know that's our
signature move
it's we wrote some mass and then instead
of kind of hand crafting this and that
and that and the robots figuring stuff
out and isn't that cool and I think that
is the same enthusiasm that I
got from there I figured out how to
reach that goal in that graph isn't that
cool so apologize for the romanticized
questions but and the silly ones if a
doctor gave you five years to live sort
of emphasizing the finiteness of our
existence
what would you try to accomplish it's
like my biggest nightmare by the way I
really like living I really don't like
dying of being told that I'm gonna die
sorry Dylan got enough for a second do
you I mean do you meditate or ponder on
your mortality on our human the fact
that this thing ends it seems to be a
fundamental feature do you think of it
as a feature or a bug - is it you you
said you don't like the idea of dying
but if I were to give you a choice of
living forever like you're not allowed
to die yeah now I'll say that I'm
wandering forever but I watch this show
it's very still it's called a good place
and they reflect a lot on this and you
know the the moral of story is that you
have to make the afterlife be finite -
because otherwise people just like
wall-e
so so I think the finance helps but but
yeah it's just um
you know I don't I don't I'm not a
religious person I don't think that
there's something after and so I think
it just ends and you stop existing and I
really like existing it's just it's such
a great privilege to exist that that
yeah it's just I think that's very part
I still think that we we like existing
so much because it ends mm-hmm and
that's so sad like it's so sad to me
every time I got find almost everything
about this life beautiful like the
silliest most mundane things are just
beautiful and I think I'm cognizant of
the fact that I find it beautiful
because it ends like it and it's so I
don't know I don't know how to feel
about that I also feel like there's a
lesson in there for robotics an AI that
is not like the finite
of things seems to be a fundamental
nature of human existence I think some
people sort of accuse me of just being
Russian and melancholic and romantic or
something but that seems to be a
fundamental nature of our existence that
should be incorporated in our reward
functions but anyway if you were
speaking of reward functions if you only
had five years what would you try to
accomplish this is the thing I I'm
thinking about this question and have a
pretty joyous moment because I don't
know that i would change mine listen I'm
what I'm I'm you know I'm trying to make
some contributions to how we understand
human AI interaction I don't think I
would change that um maybe I'll check
you know I take more trips to the
Caribbean or something but I try to
spend time so yeah I mean I try to to do
the things that bring me joy and
thinking about these things bring me joy
is d'amérique Ando think you know don't
do stuff that doesn't spark joy for the
most part I do things that spark joy
maybe I'll do like less service in the
department or something but but no I
mean I think I have amazing colleagues
and amazing students and amazing family
and friends and kind of spending time
and some balance with all of them is
what I do and I that's what I'm doing
already so I don't know that I would
really change anything so on the spirit
of positiveness oh what small act of
kindness if one pops to mind where you
one's shown you will never forget mmm
when I was in high school my friends my
my classmates did some tutoring we were
gearing up for our baccalaureate exam
and we they did some tutoring on well
someone math someone whatever I was
comfortable enough with with some of
those subjects but physics was something
that I hadn't focused
in a while and so they were all working
with this one teacher and I started
working with that teacher her name is
Nicole McConnell and she she was the one
who kind of opened up this whole world
for me because she sort of told me that
I should take the SATs and apply to go
to college abroad and you know do better
on my English and all of that and when
it came to well financially I couldn't
my parents couldn't really afford to do
all these things
she started tutoring me on physics for
free and on top of that sitting down
with me to kind of train me for SATs and
all that jazz that she had experience
with Wow
and obviously that has taken you to be
to here today also to one of the world's
experts and robotics it's funny
those little yeah dude use these small
word for no reason really kindness just
out of karma wanting to support someone
yeah yeah so we talked a ton of our
reward functions let me talk about the
the most ridiculous big question what is
the meaning of life what's the reward
function under which we humans operate
like what may be to your life may be
broader to human life in general what do
you think what gives life fulfillment
purpose happiness meaning you can't even
ask that question with a straight face
that's how ridiculous I can't like him
okay so you know you're gonna try to
answer it anyway aren't you so I was in
a planetarium once yes and you know they
show you the thing and these do man is
zoom out and this whole like you're a
speck of dust kind of thing
I think that was conceptualizing that
we're kind of you know what our humans
were just on this little planet whatever
we don't matter much in the grand scheme
of things and then my mind got really
blown cuz this doctor they doctored this
multi-verse this theory
where they kind of zoomed out and were
like this is our universe and then like
there's a bazillion other ones and it
stays pop in and out of existence so
like our whole thing that's that we
can't even fathom how big it is was like
a blimp that went in and out and I
thought I was like okay clearly what we
should be doing is try to impact
whatever local thing we can impact our
communities leave a little bit behind
they're our friends our family our local
communities and just try to be there for
other humans cuz I just
everything beyond that seems ridiculous
I mean are you like how do you make
sense of these multiverses like are you
inspired by the immensity of it do you
you can it is there like is it amazing
to you or is it almost paralyzing in
this in the mystery of it it's
frustrating I'm frustrated by my
inability to comprehend it feels very
frustrating it's look there's there's
some stuff that you know we should time
blah blah blah that we should really be
understanding and I definitely don't
understand it but you know the the
amazing physicists of the world have a
much better understanding than me Don
and the grand scheme of things so it's
very frustrating it's just it feels like
our brain don't have some fundamental
capacity yeah well yet or ever I don't
know but well this one of the dreams of
artificial intelligence is to create
systems that will aid expand our
cognitive capacity in order to
understand the build the theory of
everything when the physics and
understand what the heck these
multiverses are so I think there's no
better way to end it than talking about
the meaning of life and the fundamental
nature of the universe and akka is a
huge honor one of the my favorite
conversations I've had I really really
appreciate your time thank you for
talking to thank you for coming come
back again
thanks for listening to this
conversation with anchor dragon and
thank you to our presenting sponsor cash
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Twitter and lex friedman and now let me
leave you with some words from Isaac
Asimov your assumptions are your windows
in the world scrub them off every once
in a while or the light won't come in
thank you for listening and hope to see
you next time
you